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On episode #73 of the Infectious Disease Puscast, Daniel and Sara review the infectious disease literature for the weeks of 1/16/25 – 1/29/25. Hosts: Daniel Griffin and Sara Dong Subscribe (free): Apple Podcasts, RSS, email Become a patron of Puscast! Links for this episode Viral AGA clinical practice guideline on the prevention and treatment of hepatitis B virus reactivation (Gastroenterology) Host-microbe multiomic profiling identifies distinct COVID-19 immune dysregulation in solid organ transplant recipients (Nature Communications) Insect-specific RNA viruses detection in Field-Caught Aedes aegypti mosquitoes from Argentina using NGS technology (PLoS Neglected Tropical Diseases) Bacterial Oral regimens for rifampin-resistant, fluoroquinolone-susceptible tuberculosis (NEJM) Impact of antibiotic treatment and predictors for subsequent infections in multidrug-resistant Pseudomonas aeruginosa catheter-associated asymptomatic bacteriuria (American Journal of Infection Control) Identification of the skip phenomenon among patients With Staphylococcus lugdunensis infective endocarditis (OFID) Emergence of infective endocarditis due to Serratia spp. (OFID) Reduction of vancomycin-associated acute kidney injury with montelukast (JID) Fungal The Last of US Season 2 (YouTube) Pulmonary co-infection of Pneumocystis jirovecii and Aspergillus species (OFID) Impact of fluconazoleon outcomes of patients with primary pulmonary coccidioidomycosis (CID) Parasitic Comparative outcomes of Babesiosis in immunocompromised and non-immunocompromised hosts (CID) Miscellaneous Hidradenitis suppurativa (LANCET) A severe case associated with mixed infections of Pasteurella multocida, Bacteroides pyogenes and Fusobacterium necrophorum due to a snow leopard bite (CMI: Clinical Microbiology and Infection) INSIDE-OUT: Introduction of speakers at IDWeek events (OFID) Music is by Ronald Jenkees Information on this podcast should not be considered as medical advice.
Following the episode with Dr. Kelli Maddock, Luis decided to talk about his favorite organism: Pasteurella! This time Luis goes into more detail. What are some species of Pasteurella? Which animals are they found on? Which species are isolated from humans? This episode also covers media, biochemicals, diseases, and more.Questions? Feedback? Send those to letstalkmicro@outlook.comWant to support the podcast? Here's how:Venmo: https://venmo.com/u/letstalkmicroBuy me a Ko-fi: https://ko-fi.com/letstalkmicro
A Pasteurella multocida episode! In this episode Luis is joined by Dr. Kelli Maddock to talk about P. multocida. Kelli was a previous guest and this time returns to talk about the capsular types of P. multocida. What are these types? What diseases are associated with them? What about hemorrhagic septicemia? Kelli also talks about a model developed to look for hemorrhagic septicemia types of P. multocida using MALDI-TOF MS. Don't miss out on a great episode!Link to Dr. Maddock's article: https://www.sciencedirect.com/science/article/pii/S0167701224001799?via%3DihubQuestions? Feedback? Send those to letstalkmicro@outlook.comWant to support the podcast? Here's how:Venmo: https://venmo.com/u/letstalkmicroBuy me a Ko-fi: https://ko-fi.com/letstalkmicro
Episode 173: Acute OsteomyelitisFuture Dr. Tran explains the pathophysiology of osteomyelitis and describes the presentation, diagnosis and management of acute osteomyelitis. Dr. Arreaza provides information about Written by Di Tran, MSIII, Ross University School of Medicine. Editing and comments by Hector Arreaza, MD.You are listening to Rio Bravo qWeek Podcast, your weekly dose of knowledge brought to you by the Rio Bravo Family Medicine Residency Program from Bakersfield, California, a UCLA-affiliated program sponsored by Clinica Sierra Vista, Let Us Be Your Healthcare Home. This podcast was created for educational purposes only. Visit your primary care provider for additional medical advice.What is osteomyelitis?Osteomyelitis, in simple terms, is an infectious disease that affects both bone and bone marrow and is either acute or chronic. According to archaeological findings of animal fossils with a bone infection, osteomyelitis was more than likely to be known as a “disease for old individuals”.Our ancestors over the years have used various vocabulary terms to describe this disease until a French surgeon, Dr. Nelaton, came up with the term “Osteomyelitis” in 1844. This is the beauty of medical terms, Latin sounds complicated for some people, but if you break up the term, it makes sense: Osteo = bone, myelo = marrow, itis = inflammation. So, inflammation of the bone marrow.Traditionally, osteomyelitis develops from 3 different sources:First category is the “hematOgenous” spread of the infection within the bloodstream, as in bacteremia. It is more frequent in children and long bones are usually affected. [Arreaza: it means that the infection started somewhere else but it got “planted” in the bones]Second route is “direct inoculation” of bacteria from the contiguous site of infection “without vascular insufficiency”, or trauma, which may occur secondary to fractures or surgery in adults. In elderly patients, the infection may be related to decubitus ulcers and joint replacements.And the third route is the “contiguous” infection “with vascular insufficiency”, most seen in a patient with a diabetic foot infection.Patients with vascular insufficiency often have compromised blood supply to the lower extremities, and poor circulation impairs healing. In these situations, infection often occurs in small bones of the feet with minimal to no pain due to neuropathy.They can have ulcers, as well as paronychia, cellulitis, or puncture wounds.Thus, the importance of treating onychomycosis in diabetes because the fungus does not cause a lot of problems by itself, but it can cause breaks in the nails that can be a port of entry for bacteria to cause severe infections. Neuropathy is an important risk factor because of the loss of protective sensation. Frequently, patients may step on a foreign object and not feel it until there is swelling, purulent discharge, and redness, and they come to you because it “does not look good.”Acute osteomyelitis often takes place within 2 weeks of onset of the disease, and the main histopathological findings are microorganisms, congested blood vessels, and polymorphonuclear leukocytes, or neutrophilic infiltrates.What are the bugs that cause osteomyelitis?Pathogens in osteomyelitis are heavily depended on the patient's age. Staph. aureus is the most common culprit of acute hematogenous osteomyelitis in children and adults. Then comes Group A Strep., Strep. pneumoniae, Pseudomonas, Kingella, and methicillin-resistant Staph. aureus. In newborns, we have Group B Streptococcal. Less common pathogens are associated with certain clinical presentations, including Aspergillus, Mycobacterium tuberculosis, and Candida in the immunocompromised.Salmonella species can be found in patients with sickle cell disease, Bartonella species in patients with HIV infection, and Pasteurella or Eikenella species from human or animal bites.It is important to gather a complete medical history of the patient, such as disorders that may put them at risk of osteomyelitis, such as diabetes, malnutrition, smoking, peripheral or coronary artery disease, immune deficiencies, IV drug use, prosthetic joints, cancer, and even sickle cell anemia. Those pieces of information can guide your assessment and plan.What is the presentation of osteomyelitis?Acute osteomyelitis may present symptoms over a few days from onset of infection but usually is within a 2-week window period. Adults will develop local symptoms of erythema, swelling, warmth, and dull pain at the site of infection with or without systemic symptoms of fever or chills.Children will also be present with lethargy or irritability in addition to the symptoms already mentioned.It may be challenging to diagnose osteomyelitis at the early stages of infection, but you must have a high level of suspicion in patients with high risks. A thorough physical examination sometimes will show other significant findings of soft tissue infection, bony tenderness, joint effusion, decreased ROM, and even exposed bone. Diagnosis.As a rule of thumb, the gold standard for the diagnosis of osteomyelitis is bone biopsy with histopathology findings and tissue culture. There is leukocytosis, but then WBC counts can be normal even in the setting of acute osteomyelitis.Inflammatory markers (CRP, ESR) are often elevated although both have very low specificity. Blood cultures should always be obtained whenever osteomyelitis is suspected. A bone biopsy should also be performed for definitive diagnosis, and specimens should undergo both aerobic and anaerobic cultures. In cases of osteomyelitis from diabetic foot infection, do the “probe to bone” test. What we do is we use a sterile steel probe to detect bone which is helpful for osteomyelitis confirmation.Something that we can't miss out on is radiographic imaging, which is quite important for the evaluation of osteomyelitis. Several modalities are useful and can be used for the work-up plan; plain radiographs often are the very first step in the assessment due to their feasibility, low cost, and safety. Others are bone scintigraphy, CT-scan, and MRI. In fact, the MRI is widely used and provides better information for early detection of osteomyelitis than other imaging modalities. It can detect necrotic bone, sinus tracts, and even abscesses. We look for soft tissue swelling, cortical bone loss, active bone resorption and remodeling, and periosteal reaction. Oftentimes, plain radiography and MRI are used in combination. Treatment:Treatment of osteomyelitis actually is a teamwork effort among various medical professionals, including the primary care provider, the radiologist, the vascular, the pharmacist, the podiatrist, an infectious disease specialist, orthopedic surgeons, and the wound care team.Something to take into consideration, if the patient is hemodynamically stable it is highly recommended to delay empirical antibiotic treatment 48-72 hours until a bone biopsy is obtained. The reason is that with percutaneous biopsy ideally done before the initiation of antibiotic treatment, “the microbiological yield will be higher”.We'll have a better idea of what particular bugs are causing the problem and guide the treatment appropriately. The choice of antibiotic therapy is strongly determined by susceptibilities results. The antibiotic given will be narrowed down only for the targeted susceptible organisms. In the absence of such information, or when a hospitalized patient presents with an increased risk for MRSA infection, empiric antibiotic coverage is then administered while awaiting culture results. It should be broad-spectrum antibiotics and include coverage for MRSA, broad gram-negative and anaerobic bacteria. For example, vancomycin plus piperacillin-tazobactam, or with broad-spectrum cephalosporin plus clindamycin. Treatment will typically be given for 4 to 6 weeks.The duration between 4-6 weeks is important for complete healing, but a small study with a small sample showed that an even shorter duration of 3 weeks may be effective, but more research is needed. In certain situations, surgery is necessary to preserve viable tissue and prevent recurrent infection, especially when there are deep abscesses, necrosis, or gangrene, amputation or debridement is deemed appropriate. If the infected bone is completely removed, patients may need a shorter course of antibiotics, even a few days only. Amputation can be very distressing, especially when we need to remove large pieces of infected bone, for example, a below-the-knee amputation. We need to be sensitive to the patient's feelings and make a shared decision about the best treatment for them.In patients with diabetes, additional care must be taken seriously, patient education about the need for compliance with treatment recommendations, with careful wound care, and good glycemic control are all beneficial for the healing and recovery process. Because this is a very common problem in the clinic and at the hospital, we must keep our eyes wide open and carefully assess patients with suspected osteomyelitis to detect it promptly and start appropriate treatment. Adequate and timely treatment is linked to fewer complications and better outcomes._________________________Conclusion: Now we conclude episode number 173, “Acute Osteomyelitis.” Future Dr. Tran explained the pathophysiology, diagnosis, and management of osteomyelitis. A bone biopsy is the ideal method of diagnosis. Delaying antibiotic treatment a few days until you get a biopsy is allowed if the patient is stable, but if the patient is unstable, antibiotics must be started promptly. Dr. Arreaza mentioned the implications of amputation and that we must discuss this treatment empathically with our patients. This week we thank Hector Arreaza and Di Tran. Audio editing by Adrianne Silva.Even without trying, every night you go to bed a little wiser. Thanks for listening to Rio Bravo qWeek Podcast. We want to hear from you, send us an email at RioBravoqWeek@clinicasierravista.org, or visit our website riobravofmrp.org/qweek. See you next week! _____________________References:Bury DC, Rogers TS, Dickman MM. Osteomyelitis: Diagnosis and Treatment. Am Fam Physician. 2021 Oct 1;104(4):395-402. PMID: 34652112.Cunha BA. Osteomyelitis in elderly patients. Clin Infect Dis. 2002 Aug 1;35(3):287-93. doi: 10.1086/341417. Epub 2002 Jul 11. PMID: 12115094.Fritz JM, McDonald JR. Osteomyelitis: approach to diagnosis and treatment. Phys Sportsmed. 2008 Dec;36(1):nihpa116823. doi: 10.3810/psm.2008.12.11. PMID: 19652694; PMCID: PMC2696389.Hatzenbuehler J, Pulling TJ. Diagnosis and management of osteomyelitis. Am Fam Physician. 2011 Nov 1;84(9):1027-33. PMID: 22046943.Hofstee MI, Muthukrishnan G, Atkins GJ, Riool M, Thompson K, Morgenstern M, Stoddart MJ, Richards RG, Zaat SAJ, Moriarty TF. Current Concepts of Osteomyelitis: From Pathologic Mechanisms to Advanced Research Methods. Am J Pathol. 2020 Jun;190(6):1151-1163. doi: 10.1016/j.ajpath.2020.02.007. Epub 2020 Mar 16. PMID: 32194053.Momodu II, Savaliya V. Osteomyelitis. [Updated 2023 May 31]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK532250/Royalty-free music used for this episode: Trap Chiller by Gushito, downloaded on Nov 06, 2023, from https://www.videvo.net
We discuss getting and keeping this year's calf crop healthy. Plus, updates on Beef imports and exports, new possible genetic defects, markets, recaps, sales and more on this all new episode of the Ranch It Up Radio Show. Be sure to subscribe on your favorite podcasting app or on the Ranch It Up Radio Show YouTube Channel. EPISODE 189 DETAILS BOVINE RESPIRATORY DISEASE (BRD), MANAGE IT NOW. OVERVIEW OF BOVINE RESPIRATORY DISEASE COMPLEX Bovine respiratory disease (BRD), shipping fever pneumonia, or undifferentiated fever is a respiratory disease of cattle of multifactorial etiology with Mannheimia haemolytica and, less commonly, Pasteurella multocida, Histophilus somni ( see Histophilosis), or Mycoplasma bovis being the important bacterial agents involved. Viral pathogens may also be involved, such as bovine herpesvirus 1, parainfluenza-3 virus, and bovine respiratory syncytial virus. BRD has a multifactorial etiology and develops as a result of complex interactions between environmental factors, host factors, and pathogens. Environmental factors (eg, weaning, transport, commingling, crowding, inclement weather, dust, and inadequate ventilation) serve as stressors that adversely affect the immune and nonimmune defense mechanisms of the host animal. In addition, certain environmental factors (eg, crowding and inadequate ventilation) can enhance the transmission of infectious agents among animals. Many infectious agents have been associated with BRD. An initial pathogen (eg, a virus) may alter the animal's defense mechanisms, allowing colonization of the lower respiratory tract by bacteria. BRD is most commonly associated with the transport and assembly of large groups of recently weaned calves into feedlots. Morbidity in these types of feeder calves often peaks within the first 7–10 days after feedlot arrival. Morbidity can approach 35%–50%, and case fatality is 5%–10%; however, the levels of morbidity and mortality strongly depend on the array of risk factors present in the cattle being fed. The use of broad-spectrum antimicrobials labeled for bovine respiratory disease is the primary treatment, with macrolides and fenicols most commonly used as first-line treatment. Prevention and control are achieved via vaccination programs, preconditioning, identification and treatment of subclinically infected animals, and biosecurity. Etiology of Bovine Respiratory Disease The pathogenesis of bovine respiratory disease involves a stress factor, sometimes coupled with viral infection, which results in suppressed immune defenses and the proliferation of bacteria in the upper respiratory tract. Subsequently, these bacteria colonize the lower respiratory tract and cause bronchopneumonia with a cranioventral distribution in the lung. Many of the bacteria and viruses involved are commensal organisms of the upper respiratory tract that can be isolated from a proportion of healthy animals. Multiple stress factors contribute to the suppression of host defense mechanisms in cattle. Weaning is a noteworthy stressor, and the incidence of this disease is highest in recently weaned calves. Transportation over long distances serves as a stressor; it may be associated with exhaustion, starvation, dehydration, chilling, and overheating, depending on weather conditions. Additional important stressors include passage through auction markets; commingling, processing, and surgical procedures on arrival at the feedlot; dusty environmental conditions; and nutritional stress associated with a change to high-energy rations in the feedlot. The individual viral and bacterial etiologies, clinical signs, lesions, and treatment are discussed under Viral Infections Associated with Bovine Respiratory Disease Complex in Cattle and Bacterial Pneumonia in Cattle with Bovine Respiratory Disease Complex. Viruses associated with BRD include: bovine herpesvirus 1 (IBR) bovine respiratory syncytial virus parainfluenza-3 virus bovine viral diarrhea virus bovine adenovirus bovine coronavirus Bacteria associated with BRD include: Mannheimia haemolytica Pasteurella multocida Histophilus somni Mycoplasma bovis Bibersteinia trehalosi Control and Prevention of Bovine Respiratory Disease Prevention of bovine respiratory disease should focus on decreasing the stressors that contribute to development of the disease. Cattle should be assembled rapidly into groups, and new animals should not be introduced to established groups. Mixing of cattle from different sources should be avoided or minimized if possible; however, in the North American beef industry, this risk factor is almost unavoidable for large intensive feedlots. Transport time should be minimized, and rest periods, with access to feed and water, should be provided during prolonged transport. Calves should ideally be weaned 2–3 weeks before shipment, and surgical procedures should be performed in advance of transport; however, the availability of these “preconditioned” calves is quite limited. Cattle should receive arrival processing, which would include vaccinations and possibly metaphylactic antimicrobials within 48 hours after arrival at the feedlot. Adaptation to high-energy rations should be gradual, because acidosis, indigestion, and anorexia may inhibit the immune response. Vitamin and mineral deficiencies should be corrected. Dust control measures should be used. Metaphylaxis with long-acting antimicrobials, such as oxytetracycline, tilmicosin, florfenicol, gamithromycin, tildipirosin, or tulathromycin, has been widely adopted as a control measure given “on arrival” to cattle at high risk of developing shipping fever pneumonia. Metaphylaxis on arrival has been shown to substantially decrease morbidity, improve rate of gain, and, in some cases, decrease mortality. Mass medication in feed or water is of limited value because sick animals do not eat or drink enough to achieve inhibitory blood levels of the antimicrobial, and many of these oral antimicrobials are poorly absorbed in ruminants. On arrival, processing usually involves administration of modified live virus vaccines for viral antigens and for bacterial components of shipping fever pneumonia. Because most cases of pneumonia occur during the first 2 weeks after arrival, these on-arrival vaccines may not have adequate time to stimulate complete immunity in all individuals. When possible, vaccinations for the viral and bacterial components of shipping fever pneumonia should be given 2–3 weeks before transport or earlier and can be repeated on entry to the feedlot. Key Points BRD is the most common and costly disease affecting the North American beef cattle industry. BRD risk factors include weaning, transportation, adverse weather, commingling, and stressful events such as dehorning and castration. BRD is caused by suppressed immune responses and initial viral infection, which allow colonization of the lung by commensal URT bacteria. Preconditioning, minimizing mixing, vaccination for BRD pathogens, and metaphylaxis for high-risk animals are major control methods. Broad-spectrum antimicrobials labeled for bovine respiratory disease are the primary treatment. For More Information Key elements for implementing antimicrobial stewardship plans in bovine veterinary practices. American Association of Bovine Practitioners. Updated March 2022 Joint AABP-AVC Judicious Therapeutic Use of Antimicrobials in Cattle Cattle Industry News: Beef From Australia, New Genetic Defects, Alberta Prepares for HPAI, Trips Suspended to Michigan Farms U.S. IMPORTS OF AUSTRALIAN BEEF UP 74% FROM A YEAR AGO Australian exports of beef to the United States have soared in the last 12 months, hitting over 31,000 tons in May. Compared to the same month a year ago, that sum is 74% higher, according to global supply analyst Tim Jackson of Meat & Livestock Australia, a checkoff group for the country's red meat producers. Australian farmers have also gained beef market share in Japan and South Korea largely at the expense of U.S. exporters, Jackson said. Australia's global beef exports last month were up 9% from April and 25% from May 2023, hitting almost 114,000 tons — the highest level in more than four years. Jackson commented that the U.S. declines in production are now having a noticeable impact on export flows. NEW GENETIC DEFECT AFFECTING CATTLE MOBIDITY AND MEAT QUALITY Cattle have long been a cornerstone of agriculture, providing us with milk, meat, and various other products that nourish and sustain our communities. Ensuring the cattle's health and optimal muscle development is vital when producing high-quality beef. However, various genetic conditions can disrupt muscle metabolism, affecting animals' well-being and the quality of the meat they produce. Researchers at the University of Nebraska — Lincoln have discovered a new defect in composite cattle (Simmental, Red Angus, Gelbvieh) that often caused physical collapse when they exercised, with some calves unable to recover. This is an autosomal recessive genetic defect, which means both parents of affected calves must carry one copy of the mutation. TRIPS SUSPENDED TO MICHIGAN FARMS The Michigan Department of Health and Human Services asked the public to postpone visits to farms with dairy herds and poultry flocks amid the HPAI outbreak. Over the past few weeks, Michigan has reported two human cases of the H5 virus. The department asked schools, daycares, camps and other programs to delay any planned field trips to farms. ALBERTA PREPARES FOR HPAI IN CATTLE According to Chris Scott with Meating Place dot com, Confirmation of H5 virus infections in U.S. dairy cows is prompting animal health officials in Canada to consider their options to prevent the virus from affecting herds north of the U.S. border. Dr. Keith Lehman, Alberta's chief veterinarian, told CBC News that vigilant surveillance is critical to protecting the Canadian dairy herd from a virus that has been confirmed among dairy cows in nine U.S. states so far. Canada imposed new import rules last month that require lactating cows from U.S. dairy farms test negative for H5 within seven days of export to help the nation maintain its HPAI-free status among cattle. UPCOMING SALES & EVENTS ISA Beefmasters: October 5, 2024, San Angelo, Texas BULL SALE REPORT & RESULTS Churchill Cattle Company Van Newkirk Herefords Gardiner Angus Ranch Cow Camp Ranch Jungels Shorthorn Farms Ellingson Angus Edgar Brothers Angus Schaff Angus Valley Prairie Hills Gelbvieh Clear Springs Cattle Company CK Cattle Mrnak Hereford Ranch Frey Angus Ranch Hoffmann Angus Farms Topp Herefords River Creek Farms Upstream Ranch Gustin's Diamond D Gelbvieh Schiefelbein Farms Wasem Red Angus Raven Angus Krebs Ranch Yon Family Farms Chestnut Angus Eichacker Simmentals & JK Angus Windy Creek Cattle Company Pedersen Broken Heart Ranch Mar Mac Farms Warner Beef Genetics Arda Farms & Freeway Angus Leland Red Angus & Koester Red Angus Fast - Dohrmann - Strommen RBM Livestock Weber Land & Cattle Sundsbak Farms Hidden Angus Wheatland Cattle Company Miller Angus Farms L 83 Ranch U2 Ranch Vollmer Angus Ranch A & B Cattle Carter Angus Farms Roller Ranch Montgomery Ranch Jorgensen Farms DLCC Ranch Four Hill Farm North Country Angus Alliance Spruce Hill Ranch Wilson Angus FEATURING Dave Sjeklocha, DVM Merck Animal Health @merckanimalhealth https://www.merckvetmanual.com/ https://www.merck-animal-health-usa.com/ Mark VanZee Livestock Market, Equine Market, Auction Time https://www.auctiontime.com/ https://www.livestockmarket.com/ https://www.equinemarket.com/ @LivestockMkt @EquineMkt @AuctionTime Kirk Donsbach: Stone X Financial https://www.stonex.com/ @StoneXGroupInc Shaye Koester Casual Cattle Conversation https://www.casualcattleconversations.com/ @cattleconvos Questions & Concerns From The Field? Call or Text your questions, or comments to 707-RANCH20 or 707-726-2420 Or email RanchItUpShow@gmail.com FOLLOW Facebook/Instagram: @RanchItUpShow SUBSCRIBE to the Ranch It Up YouTube Channel: @ranchitup Website: RanchItUpShow.com https://ranchitupshow.com/ The Ranch It Up Podcast available on ALL podcasting apps. Rural America is center-stage on this outfit. AND how is that? Tigger & BEC Live This Western American Lifestyle. Tigger & BEC represent the Working Ranch world and cattle industry by providing the cowboys, cowgirls, beef cattle producers & successful farmers the knowledge and education needed to bring high-quality beef & meat to your table for dinner. Learn more about Jeff 'Tigger' Erhardt & Rebecca Wanner aka BEC here: TiggerandBEC.com https://tiggerandbec.com/ #RanchItUp #StayRanchy #TiggerApproved #tiggerandbec #rodeo #ranching #farming References https://www.stonex.com/ https://www.livestockmarket.com/ https://www.equinemarket.com/ https://www.auctiontime.com/ https://gelbvieh.org/ https://www.imogeneingredients.com/ https://alliedgeneticresources.com/ https://westwayfeed.com/ https://medoraboot.com/ http://www.gostockmens.com/ https://www.imiglobal.com/beef https://www.tsln.com/ https://transova.com/ https://axiota.com/ https://www.merckvetmanual.com/respiratory-system/bovine-respiratory-disease-complex/overview-of-bovine-respiratory-disease-complex#Key-Points_v74932778 https://www.meatingplace.com/Industry/News/Details/114883 https://www.cattlebusinessweekly.com/articles/new-genetic-defect-impacting-cattle-morbidity-and-meat-quality/ https://www.meatingplace.com/Industry/News/Details/114869 https://www.meatingplace.com/Industry/News/Details/114841 https://www.merck-animal-health-usa.com/
Infeksjoner med Pasteurella-bakterien har blitt et betydelig problem i norske oppdrettsanlegg de siste årene. Forskere på Veterinærinstituttet prøver å finne ut årsaken eller årsakene til dette. Mye tyder på at den egentlig ikke sprer seg så lett, men hvorfor har den da likevel gitt så mye sykdom?Veterinærinstituttet leder et prosjekt, finansiert av FHF, som skal gi mer kunnskap om bakterien og bekjempelsen av den. Prosjektet har som mål å etablere smittemodeller for testing av fremtidig vaksiner og dokumentere Pasteurella sitt biofysiske egenskaper, effekt av relevante biosikkerhetstiltak, bakteriens overlevelsesevner i miljø og sprednings- og infeksjonsdynamikk.Dette er tema i denne episoden av VETpodden og gjesten vår er forsker ved Veterinærinstituttet Duncan Colquhoun. Han kommer selv fra Skottland, hvor Pasteurella har vært historisk et større problem enn i Norge. Hosted on Acast. See acast.com/privacy for more information.
In this episode, we review the high-yield topic of Pasteurella multocida from the Microbiology section. Follow Medbullets on social media: Facebook: www.facebook.com/medbullets Instagram: www.instagram.com/medbulletsofficial Twitter: www.twitter.com/medbullets --- Send in a voice message: https://podcasters.spotify.com/pod/show/medbulletsstep1/message
AABP Executive Director Dr. Fred Gingrich is joined by two beef producers – Craig Bieber of Beiber Red Angus and Cole Ratzburg of Bobcat Angus. This episode of Have You Herd? is sponsored by Merck Animal Health, makers of Bovilis Vista Once SQ. It's shown effective against the major causes of BRD plus Pasteurella multocida and BVD Type 1b. Give calves the most complete BRD coverage in a single dose. Find our more information by visiting this page. The AABP Genetics and Genomics Committee develops resources for AABP members on the importance of genomics in the beef and dairy industry and developed this podcast. Our producer guests discuss the traits they focus on when selecting cattle, how they incorporate genomics testing and using indexes for bull selection. They discuss how they keep select replacements and give suggestions for what cow-calf producers should focus on when selecting bulls. Both producers believe that genomic testing has benefits their herds and helped them achieve their goals in a more rapid manner stating that the testing is economically advantageous to their operations. Finally, Bieber and Ratzburg offer suggestions for utilizing veterinarians to help make decisions on genetics and genomics within their herds. Find out more information about Bieber Red Angus on this page and Bobcat Angus here. For more information about the AABP Genetics and Genomics Committee, or to join the committee, visit this link. If you are attending the AABP conference and are interested in genetics and genomics, please join the committee meeting on Thursday, Sept. 21.
AABP Executive Director Dr. Fred Gingrich is joined by Merck Animal Health Technical Services Veterinarian Dr. Brent Meyer. This episode of Have You Herd? is sponsored by Merck Animal Health. Could your cattle be more covered for BRD? If you're not using Bovilis Vista Once SQ, the answer is yes! It's shown effective against the major causes of BRD plus Pasteurella multocida and BVD Type 1b. No other vaccine covers as much and with industry-leading duration of immunity. Give calves the most complete BRD coverage in a single dose. Bovilis Vista Once SQ – another way Merck Animal Health works for you. Meyer begins our discussion with a refresher on Pasteurella multocida and the role it plays in the bovine respiratory disease complex. He also discusses some of the misconception about P. multocida and how veterinarians can educate producers on this pathogen. Meyer states that P. multocida typically is the number one bacteria isolated in dairy calves and the second most common isolate in beef calves with BRD from diagnostic lab samples. We also discuss some classic signs of a P. multocida problem in a herd and how veterinarians can assist producers with both ante-mortem and post-mortem diagnostics working with their reference laboratories. Myer reviews both husbandry principles and vaccination with Bovilis Vista Once SQ to aid in prevention of this pathogen as part of the BRD complex. He encourages veterinarians to contact their Merck Animal Health technical services veterinarian for further information. Please visit this link for more information about Bovilis Vista Once SQ.
3.16 Pasteurella Multocida Microbiology review for the USMLE Step 1 exam Pasteurella multocida is a gram-negative coccobacillus that commonly causes infection following animal bites or scratches Classic presentation is a young male with swollen, red, and tender skin at the site of the bite or scratch Symptoms develop rapidly, usually within 3-48 hours after injury In rare cases, infection can progress to necrotizing fasciitis or bacteremia Diagnosis is made clinically using patient history and symptoms Treatment of choice is amoxicillin-clavulanate, and infections usually resolve with little complications when treated with antibiotic
3.04 Gram Negative Bacteria Microbiology review for the USMLE Step 1 Exam. Gram negative bacteria are characterized by a thin cell wall surrounded by a lipid outer membrane They do not retain the violet gram stain and appear pink after staining Gram negative bacteria can be classified by shape: cocci, coccobacilli, bacilli, and spirals Gram negative cocci include Neisseria species, which can be further categorized as maltose fermenters or non maltose fermenters Gram negative coccobacilli include: Bordetella pertussis, Haemophilus influenzae, Pasteurella, Francisella tularensis, Brucella, and Acinetobacter Gram negative bacilli can be divided into lactose fermenting and non lactose fermenting categories Lactose fermenting gram negative bacilli include: Escherichia coli, Klebsiella, Enterobacter, Citrobacter, and Serratia Non lactose fermenting gram negative bacilli can be further divided into oxidase positive and oxidase negative Oxidase positive non lactose fermenting gram negative bacilli include Pseudomonas Oxidase negative non lactose fermenting gram negative bacilli include Shigella, Yersinia, and Salmonella Gram negative spirals can be divided into oxidase positive and oxidase negative categories Oxidase positive gram negative spirals include Vibrio species, Helicobacter pylori, and Campylobacter jejuni Oxidase negative gram negative spirals include Borrelia burgdorferi (cause of lyme disease) and Treponema pallidum (cause of syphilis)
Instagram follower suggestion: After mentioning on a post that Pasteurella was my favorite, a follower suggested for me to make an episode about it. In this episode I talk about Pasteurella, and why do I like it.
What is mastitis?Mastitis, an inflammation of the mammary gland (udder), is one of the most common reasons for culling ewes in sheep flocks. Mastitis is usually due to a bacterial infection but can also have non-infectious causes such as injury. It can occur any time in the production cycle of the ewe but is most common two to four weeks post-lambing. It can prove costly for breeders. In general, it usually occurs in animals raising more than one lamb or with an excessively high rate of milk production. Some cases occur when sheep are being grazed at too high a stocking rate, though the vast majority of all mastitis cases in sheep occur within a few weeks of lambing or just as weaning is due to start The infection occurs when bacteria make their way into the udder of the ewe. It is most common in breeds that produce multiple offspring per lambing. Forms of the disease There are two main types of mastitis in sheep. Mastitis can be classified as clinical and subclinical. Subclinical mastitis is a difficult one to identify and ewes tend to only show low growth rates when affected. Poor weather and a lack of adequate nutrition can cause subclinical mastitis to develop into clinical mastitis. Subclinical mastitis can also cause the death of twin lambs. Clinical mastitis refers to an infection that becomes obvious clinically. Mastitis can rapidly progress, eventually turning parts of the udder black, if the infection becomes severe enough to compromise the blood supply to the udder. Ewes usually appear lame and weak, with lambs also lethargic and depressed. Lambs can die because of a lack of milk when ewes have clinical mastitis and they can die from the infection gained from digesting the infected milk. Euthanasia may be considered in severely affected animals but best to consult your vet for advice. Picture shows clinical mastitis. When treating mastitis, early detection is key and can prevent further spreading of the infection. Your Vet may provide you with an antibiotic and painkiller for your animal. or may make other treatment suggestions. Some cases of mastitis are due to yeast or fungi and giving these animals antibiotics makes them worse. It is important to get a diagnosis and treat appropriately. It is a good idea to mark all ewes once treatment occurs, so they can be identified for possible culling at weaning. What causes it?The primary cause of mastitis in cattle, goats and sheep are well-recognized groups of microorganisms, Streptococcus sp., Staphylococcus sp., Pasteurella sp. and coliforms, Escherichia coli, Enterobacter sp., and Klebsiella sp. Yeast and fungus have also been found frequently infecting the udder, but usually go unnoticed because they produce a mild or subclinical mastitis. Picture shows severe mastitis resulted in an erupted udder How to treat it?Disinfect the teat end with chlorhexidine or iodine-based disinfectants and infuse a tube of mastitis antibiotic through the teat canal if the cause of the mastitis is a bacterial infection. If the problem is a bacterial infection the ewe can be give an injection of an antibiotic and nonsteroidal anti-inflammatory drug as directed by your vet.The udders of ewes should be examined physically for hard lumps after weaning and before breeding. Ewes with ‘lumpy bags' may be considered for culling. The milk supply of these ewes will be decreased, and the amount of decrease will depend upon the amount of tissue damaged. How to prevent it? A strong immune system is the key to preventing mastitis and similar infections. Injectable trace mineral supplement products such as Multimin can help during times of stress such as lambing and weaning.A good management
En 2015, una bacteria mató a la mayoría de los antílopes saiga en la estepa del centro de Kazajistán. Los expertos temían que los animales se extinguieran. Ahora, todo ha cambiado: en la estepa se han multiplicado los nacimientos.
2015 tötete ein Bakterium den größten Teil der Saiga-Antilopen in der Steppe Zentralkasachstans. Experten befürchteten ein Aussterben der Tiere. Doch nun ist davon keine Rede mehr: In der Steppe gab es einen Babyboom.
In 2015, a mysterious disease killed 90% of the saiga antelope in the steppe of Central Kazakhstan. Experts feared they'd all be lost. But those fears have given way to hope: There's a baby boom on the steppe.
Welcome back to USMLE Listen This is MICROBIOLOGY Chapter 6: Enterobacteriaceae! Whether you're on a run or driving, this is The PERFECT podcast to initiate your auditory learning for the USMLE Step 1! In this episode, it's all about USMLE-important Gram Enterobacteriacaea Important exam related information on gram-negative bacteria in the ENTEROBACTERIACEAE FAMILY which include E.coli, Klebsiella, Shigella, Yersinia, Proteus, Salmonella, Haemophilus, Gardnerella, Pasteurella, and Bacteroides. We will also go over bacterial infections caused by ANIMAL AND HUMAN BITES as well as the different bacteria that cause ENDOCARDITIS! Review EACH USMLE critical Enterobacteriaceae: Features Transmission & Predisposing Factors Pathogenesis Diseases Associated Treatment Important to Know Info! As always, you can email us at USMLElisten@gmail.com for your questions, anything you need to be cleared, or suggestions on how we can improve and initiate your auditory learning for the USMLE Step 1. Sources for USMLE LISTEN include First Aid, Osmosis, Uworld, and Kaplan study guides. This is Mark Labella, you can follow or message me on Instagram at markjlabella. See you in the next episode for your auditory learning at USMLE LISTEN!
Gram negative rods - Pasteurella multocida
Today is March twelfth and we're going to talk about two organisms that can cause skin infections and are transmitted from animals. And ironically, one more reason why dogs are better than cats. I swear I didn't plan it this way, please don't at me. High-yield microbiology review for medical boards step 1, and two boards-style practice questions --- Send in a voice message: https://anchor.fm/bradleysmicroboardreview/message Support this podcast: https://anchor.fm/bradleysmicroboardreview/support
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You can also support by donating through PayPal.com at the link below: Hare of the Rabbit PayPal Thank you for your support, Jeff Hittinger. Snow Shoe Hare - Snoring and Nasal Obstruction in Rabbits - The Shot Hare - Perplexing Difference between Hares and Rabbits Hares and rabbits are related, but there are some key differences. Hares tend to be larger than rabbits and have longer legs and bigger ears. When threatened, rabbits typically freeze and rely on camouflage, as compared to hares, who use their big feet to flee at the first sign of danger. Rabbits are born blind and helpless, while hares are born fully furred and ready to run. About the Snowshoe Hare Snowshoe hares are forest-dwellers that prefer the thick cover of brushy undergrowth. The smallest species of the Lepus genus, the snowshoe hare (Lepus americanus) is a rabbit-sized mammal that is incredibly adapted to its seasonally variable environment. The snowshoe hare is named for its hind feet, which are adapted for traveling across snowy ground and are therefore noticeably large relative to the hare’s body mass. Population Range The snowshoe hare has the most extensive range of all New World hares and is found in many northern and western U.S. states, as well as in all provinces of Canada except Nunavut. They are primarily a northern species that inhabits boreal forests and can also range as far north as the shores of the Arctic Ocean. Along North American mountain ranges, where elevation simulates the environment of more northerly latitudes, they can be found as far south as Virginia (the Appalachians) and New Mexico (the Rockies). Snowshoe hares occur from Newfoundland to Alaska; south in the Sierra Nevada to central California; in the Rocky Mountains to southern Utah and northern New Mexico; and in the Appalachian Mountains to North Carolina and Tennessee. Snowshoe hares are primarily found in boreal forests and upper montane forests; within these forests, they favor habitats with a dense shrub layer. In the Pacific Northwest, snowshoe hares occupy diverse habitats, including mature conifers (mostly Douglas-fir [Pseudotsuga menziesii] and variants), immature conifers, alder (Alnus spp.)/salmonberry (Rubus spectabilis), Sitka spruce (Picea sitchensis)/salal (Gaultheria shallon), and cedar (Thuja spp.) swamps. In western Oregon, snowshoe hares were present in brush patches of vine maple (Acer circinatum), willows (Salix spp.), rhododendrons (Rhododendron spp.), and other shrubs. In Utah, snowshoe hares used Gambel oak (Quercus gambelli) in the northern portion of the Gambel oak range. In the Southwest, the southernmost populations of snowshoe hares occur in the Sangre de Cristo Mountains, New Mexico, in subalpine scrub: narrow bands of shrubby and prostrate conifers at and just below timberline that are usually composed of Engelmann spruce (Picea engelmannii), bristlecone pine (Pinus aristata), limber pine (P. flexilis), and/or common juniper (Juniperus communis). In Minnesota, snowshoe hares use jack pine (P. banksiana) uplands, edges, tamarack (Larix laricina) bogs, black spruce (Picea mariana) bogs, and sedge (Carex spp.), alder, and scrub fens. In New England, snowshoe hares favor second-growth aspen (Populus spp.)-birch (Betula spp.) near conifers, but other forest types occupied by snowshoe hares include aspens, paper birch (B. papyrifera), northern hardwoods, red maple (A. rubrum), balsam fir (Abies balsamea), red spruce (Picea rubens)-balsam fir, eastern hemlock (Tsuga canadensis), northern red oak (Quercus rubra), oak (Quercus spp.)-pine (Pinus spp.), eastern white pine (P. strobus)-northern red oak-red maple, and eastern white pine. Snowshoe hares also use shrub swamps dominated by buttonbush (Cephalanthus occidentalis), alders, and silky dogwood (Cornus ammomum). Locations of subspecies are as follows: Lepus americanus americanus (Erxleben) – Ontario, Manitoba, Saskatchewan, Alberta, Montana, and North Dakota L. a. cascadensis (Nelson) – British Columbia and Washington L. a. columbiensis (Rhoads) – British Columbia, Alberta, and Washington L. a. dalli (Merriam) – Mackenzie District, British Columbia, Alaska, Yukon L. a. klamathensis (Merriam) – Oregon and California L. a. oregonus (Orr) – Oregon L. a. pallidus (Cowan) – British Columbia L. a. phaeonotus (J. A. Allen) – Ontario, Manitoba, Saskatchewan, Michigan, Wisconsin, and Minnesota L. a. pineus (Dalquest) – British Columbia, Idaho, and Washington L. a. seclusus (Baker and Hankins) – Wyoming L. a. struthopus (Bangs) – Newfoundland, Nova Scotia, New Brunswick, Prince Edward Island, Quebec, and Maine L. a. tahoensis (Orr) – California, western Nevada L. a. virginianus (Harlan) – Ontario, Quebec, Maine, New Hampshire, Vermont, Massachusetts, New York, Pennsylvania, Ohio, West Virginia, Maryland, Virginia, North Carolina, and Tennessee L. a. washingtonii (Baird) – British Columbia, Washington, and Oregon Description Snowshoe hares have an interesting adaptation that helps protect them against predators. Depending on the season, their fur can be a different color. During the winter, snowshoe hares are white, which helps them blend in with the snow. When the seasons change to spring and summer, snowshoe hares turn a reddish-brown. This color helps them camouflage with dirt and rocks. Not every part of the snowshoe hare changes color throughout the year. An important identification trick is to look at a snowshoe hare's ears. The tips of the ears are always black no matter the season. The hind legs of a snowshoe hare are noticeably larger, and have more fur and larger toes than those of other rabbits or hares. These adaptations provide additional surface area and support for walking on snow. The hind legs are what give the hare its common name. The fur of the snowshoe hare is extremely thick and has one of the highest insulation values of all mammals. Another adaptation which ensures that the snowshoe hare can survive in an environment that drastically changes seasonally is that its fur changes color between summer and winter. In winter, almost all individuals undergo molting that transforms the hare’s brown summer coat into one that is pure white apart from the black-tipped ears and the feet, which remain grey. It is thought that this enables the snowshoe hare to become camouflaged, and has evolved to coincide with snow cover. The snowshoe hare’s relatively short ears are also an adaptation to reduce heat loss in the winter. The female of this species tends to weigh approximately 10 to 25 percent more than the male. Physical Description Snowshoe hares range in length from 413 to 518 mm, of which 39 to 52 mm are tail. The hind foot, long and broad, measures 117 to 147 mm in length. The ears are 62 to 70 mm from notch to tip. Snowshoe hares usually weigh between 1.43 and 1.55 kg. Males are slightly smaller than females, as is typical for leporids. In the summer, the coat is a grizzled rusty or grayish brown, with a blackish middorsal line, buff flanks and a white belly. The face and legs are cinnamon brown. The ears are brownish with black tips and white or creamy borders. During the winter, the fur is almost entirely white, except for black eyelids and the blackened tips on the ears. The soles of the feet are densely furred, with stiff hairs (forming the snowshoe) on the hind feet. Coloring Hares are a bit larger than rabbits, and they typically have taller hind legs and longer ears. Snowshoe hares have especially large, furry feet that help them to move atop snow in the winter. They also have a snow-white winter coat that turns brown when the snow melts each spring. It takes about ten weeks for the coat to completely change color. The snowshoe hare (Lepus americanus), also called the varying hare, or snowshoe rabbit, is a species of hare found in North America. It has the name "snowshoe" because of the large size of its hind feet. The animal's feet prevent it from sinking into the snow when it hops and walks. Its feet also have fur on the soles to protect it from freezing temperatures. For camouflage, its fur turns white during the winter and rusty brown during the summer. Its flanks are white year-round. The snowshoe hare is also distinguishable by the black tufts of fur on the edge of its ears. Its ears are shorter than those of most other hares. Preferred habitat Major variables in habitat quality include average visual obstruction and browse biomass. Snowshoe hares prefer young forests with abundant under-stories. The presence of cover is the primary determinant of habitat quality, and is more significant than food availability or species composition. Species composition does, however, influence population density; dense softwood under-stories support greater snowshoe hare density than hardwoods because of cover quality. In Maine, female snowshoe hares were observed to be more common on sites with less cover but more nutritious forage; males tended to be found on sites with heavier cover. Winter browse availability depends on height of understory brush and winter snow depth; 6-to-8-foot-tall (1.8 to 2.4 m) saplings with narrow stem diameters are required for winter browse in heavy snow. In northern regions, snowshoe hares occupy conifer and mixed forests in all stages of succession, but early successional forests foster peak abundance. Deciduous forests are usually occupied only in early stages of succession. In New England, snowshoe hares preferred second-growth deciduous, coniferous, and mixed woods with dense brushy under stories; they appear to prefer shrubby old-field areas, early- to mid-successional burns, shrub-swamps, bogs, and upper montane krumholz vegetation. In Maine, snowshoe hares were more active in clear-cut areas than in partially cut or uncut areas. Sapling densities were highest on 12- to 15-year-old plots; these plots were used more than younger stands. In northern Utah, they occupied all the later stages of succession on quaking aspen and spruce-fir, but were not observed in meadows. In Alberta, snowshoe hares use upland shrub-sapling stages of regenerating aspens (either postfire or postharvest). In British Columbia overstocked juvenile lodge-pole pine (Pinus contorta) stands formed optimal snowshoe hare habitat. In western Washington, most un-burned, burned, or scarified clear-cuts will normally be fully occupied by snowshoe hares within four to five years, as vegetation becomes dense. In older stands (more than 25 years), stem density begins to decline and cover for snowshoe hares decreases. However, in north-central Washington, they may not colonize clear-cuts until six or seven years, and it may take 20 to 25 years for their density to reach maximum. Winter snowshoe hare pellet counts were highest in 20-year-old lodge-pole pine stands, lower in older lodge-pole stands, and lowest in spruce-dominated stands. In western Oregon, snowshoe hares were abundant only in early successional stages, including stable brushfields. In west-central Oregon, an old-growth Douglas-fir forest was clear-cut and monitored through 10 years of succession. A few snowshoe hares were noted in adjacent virgin forest plots; they represented widely scattered, sparse populations. One snowshoe hare was observed on the disturbed plot 2.5 years after it had been clear-cut and burned; at this stage, ground cover was similar to that of the uncut forest. By 9 years after disturbance, snowshoe hare density had increased markedly. In western Washington, snowshoe hares routinely used steep slopes where cover was adequate; most studies, however, suggest they tend to prefer gentle slopes. Moonlight increases snowshoe hare vulnerability to predation, particularly in winter. They tend to avoid open areas during bright phases of the moon and during bright periods of a single night. Their activity usually shifts from coniferous under-stories in winter to hardwood under-stories in summer. Vegetative structure plays an important role in the size of snowshoe hare home ranges. Snowshoe hares wander up to 5 miles (8 km) when food is scarce. In Montana home ranges are smaller in brushy woods than in open woods. In Colorado and Utah, the average home range of both sexes was 20 acres (8.1 ha). On the Island of Montreal in Quebec, the average daily range for both sexes was 4 acres (1.6 ha) in old-field mixed woods. In Montana, the home range averaged 25 acres (10 ha) for males and 19 acres (7.6 ha) for females. In Oregon the average snowshoe hare home range was 14.6 acres (5.9 ha).[32] Home Range During its active period, a hare may cover up to 0.02 square kilometers of its 0.03 to 0.07 square kilometer home range. Cover requirements Snowshoe hares require dense, brushy, usually coniferous cover; thermal and escape cover are especially important for young hares. Low brush provides hiding, escape, and thermal cover. Heavy cover 10 feet (3 m) above ground provides protection from avian predators, and heavy cover 3.3 feet (1 m) tall provides cover from terrestrial predators. Overwinter survival increases with increased cover. A wide variety of habitat types are used if cover is available. Base visibility in good snowshoe hare habitat ranges from 2% at 16.5 feet (5 m) distance to 0% at 66 feet (20 m). Travel cover is slightly more open, ranging from 14.7% visibility at 16.5 feet (5 m) to 2.6% at 66 feet (20 m). Areas with horizontal vegetation density of 40 to 100% at 50 feet (15 m) are adequate snowshoe hare habitat in Utah. Food habits Snowshoe hares eat a variety of plant materials. Forage type varies with season. Succulent green vegetation is consumed when available from spring to fall; after the first frost, buds, twigs, evergreen needles, and bark form the bulk of snowshoe hare diets until spring greenup. Snowshoe hares typically feed at night and follow well-worn forest paths to feed on various plants and trees. Winter Snowshoe hares prefer branches, twigs, and small stems up to 0.25 inch (6.3 mm) diameter; larger stems are sometimes used in winter. In Yukon, they normally eat fast-growing birches and willows, and avoid spruce. At high densities, however, the apical shoots of small spruce are eaten. The snowshoe hare winter diet is dominated by bog birch (Betula glandulosa), which is preferred but not always available. Greyleaf willow (Salix glauca) is eaten most often when bog birch is not available. Buffaloberry (Shepherdia canadensis) is the fourth most common diet item. White spruce (Picea glauca) is eaten, but not preferred. In Alaska, spruce, willows, and alders comprise 75% of snowshoe hare diets; spruce needles make up nearly 40% of the diet. In northwestern Oregon, winter foods include needles and tender bark of Sitka spruce, Douglas-fir, and western hemlock (Tsuga heterophylla); leaves and green twigs of salal; buds, twigs, and bark of willows; and green herbs. In north-central Washington, willows and birches are not plentiful; snowshoe hares browse the tips of lodgepole pine seedlings. In Utah, winter foods include Douglas-fir, willows, snowberry (Symphoricarpos spp.), maples, and serviceberry (Amelanchier spp.). In Minnesota, aspens, willows, hazelnut (Corylus spp.), ferns (Pteridophyta spp.), birches, alders, sumacs (Rhus spp.), and strawberries (Fragaria spp.) are winter foods. Winter foods in New York include eastern white pine, red pine (Pinus resinosa), white spruce, paper birch, and aspens. In Ontario, sugar maple (Acer saccharum), striped maple (A. pensylvanicum), red maple, other deciduous species, northern white-cedar (T. occidentalis), balsam fir, beaked hazelnut (C. cornuta), and buffaloberry were heavily barked. In New Brunswick, snowshoe hares consumed northern white-cedar, spruces, American beech (Fagus grandifolia), balsam fir, mountain maple (A. spicatum), and many other species of browse. In Newfoundland, paper birch is preferred. Spring, summer and autumn In Alaska, snowshoe hares consume new leaves of blueberries (Vaccinium spp.), new shoots of field horsetails (Equisetum arvense), and fireweed (Epilobium angustifolium) in spring. Grasses are not a major item due to low availability associated with sites that have adequate cover. In summer, leaves of willows, black spruce, birches, and bog Labrador tea (Ledum groenlandicum) are also consumed. Black spruce is the most heavily used and the most common species in the area. Pen trials suggest black spruce is not actually preferred. Roses (Rosa spp.) were preferred, but a minor dietary item, as they were not common in the study area. In northwest Oregon, summer foods include grasses, clovers (Trifolium spp.), other forbs, and some woody plants, including Sitka spruce, Douglas-fir, and young leaves and twigs of salal. In Minnesota, aspens, willows, grasses, birches, alders, sumacs, and strawberries are consumed when green. In Ontario, summer diets consist of clovers, grasses, and forbs. Behavior Snowshoe hares feed at night, following well worn forest paths to feed on trees and shrubs, grasses, and plants. These animals are nimble and fast, which is fortunate, because they are a popular target for many predators. Lynx, fox, coyote, and even some birds of prey hunt this wary hare. Hares like to take dust baths. These help to remove ectoparasites from the hares' fur. Snowshoe hares are also accomplished swimmers. They occasionally swim across small lakes and rivers, and they have been seen entering the water in order to avoid predators. With the hindfeet splayed and the front feet close together, a snowshoe hare can erupt into a full run from a sitting position, attaining bursts of speeds of up to 40-56 km/h (25-35 mph) in a matter of seconds. Social System - The species is solitary, promiscuous, and sedentary. Males compete aggressively for receptive females, biting and scratching each other. Rarely, such encounters prove fatal to one of the combatants. Both sexes occupy small, overlapping home ranges of 1.6-4.8 ha (4-12 acre) that vary in shape with the configuration of the habitat. This species, which is well known for its dramatic fluctuations in numbers in other parts of its range, maintains relatively stable populations is the Adirondacks, and within suitable habitat, some of the highest densities anywhere, 1.7 per ha (0.7 per acre) Communication - Snowshoe hares use visual, tactile, vocal, chemical, and mechanical signals to communicate. Individuals "thump" with their hindfeet, perhaps as an alarm signal. During courtship, partners may touch noses before a male rushes or chases the female. Chases then alternate between the two, both stopping abruptly and turing to leap over the back of the other. Both may urinate on the other while leaping. Snowshoe hares perform guttural hisses at the conclusion of mating, and grunt, snort, or growl in other contexts. When captured, injured or frightened, they may scream. Communication and Perception Snowshoe hares have acute hearing, which presumably helps them to identify approaching predators. They are not particularly vocal animals, but may make loud squealing sounds when captured. When engaging in aggressive activities, these animals may hiss and snort. Most communication between hares involves thumping the hind feet against the ground. In summer, it feeds on plants such as grass, ferns and leaves; in winter, it eats twigs, the bark from trees, and buds from flowers and plants and, similar to the Arctic hare, has been known to steal meat from baited traps. Hares are carnivorous under the availability of dead animals, and have been known to eat dead rodents such as mice due to low availability of protein in a herbivorous diet. It can sometimes be seen feeding in small groups. This animal is mainly active at night and does not hibernate. The snowshoe hare has been reported to make many characteristic hare vocalizations, which are mainly emitted as a result of fear or stress associated with capture or predation. A common snowshoe hare vocalization is a high-pitched squeal, and other noises include whines, grunts and clicking sounds. Snowshoe hares are crepuscular to nocturnal. They are shy and secretive and spend most of the day in shallow depressions, called forms, scraped out under clumps of ferns, brush thickets, and downed piles of timber. They occasionally use the large burrows of mountain beavers (Aplodontia rufa) as forms. The snowshoe hare is a social species and has been spotted in groups of up to 25 individuals in one forest clearing at night, unlike most other Lepus species which are solitary until the mating season. Diurnal activity level increases during the breeding season. Juveniles are usually more active and less cautious than adults. Snowshoe hares are active year-round. The breeding season for hares is stimulated by new vegetation and varies with latitude, location, and yearly events (such as weather conditions and phase of snowshoe hare population cycle). Breeding generally begins in late December to January and lasts until July or August. In northwestern Oregon, male peak breeding activity (as determined by testes weight) occurs in May and is at the minimum in November. In Ontario, the peak is in May and in Newfoundland, the peak is in June. Female estrus begins in March in Newfoundland, Alberta, and Maine, and in early April in Michigan and Colorado. First litters of the year are born from mid-April to May. The gestation period is 35 to 40 days; most studies report 37 days as the average length of gestation. Litters average three to five leverets depending on latitude, elevation, and phase of population cycle, ranging from one to seven. Deep snow-pack increases the amount of upper-branch browse available to snowshoe hares in winter, and therefore has a positive relationship with the nutritional status of breeding adults. Litters are usually smaller in the southern sections of their range since there is less snow. Newborns are fully furred, open-eyed, and mobile. T hey leave the natal form within a short time after birth, often within 24 hours. After leaving the birthplace, siblings stay near each other during the day, gathering once each evening to nurse. Weaning occurs at 25 to 28 days except for the last litter of the season, which may nurse for two months or longer. Female snowshoe hares can become pregnant anytime after the 35th day of gestation. The second litter can therefore be conceived before the first litter is born (snowshoe hares have twin uteri). Pregnancy rates ranged from 78 to 100% for females during the period of first litter production, 82 to 100% for second litters, and for the periods of third and fourth litters pregnancy rates vary with population cycle. In Newfoundland, the average number of litters per female per year ranged from 2.9 to 3.5, and in Alberta the range was from 2.7 to 3.3. In Alberta the average number of litters per year was almost 3 just after a population peak and 4 just after the population low. Females normally first breed as 1-year-olds. Juvenile breeding is rare and has only been observed in females from the first litter of the year and only in years immediately following a low point in the population cycle. Reproduction Like most hares (and rabbits), snowshoe hares are prolific breeders. Females have two or three litters each year, which include from one to eight young per litter. Young hares, called leverets, require little care from their mothers and can survive on their own in a month or less. Snowshoe hare populations fluctuate cyclically about once a decade—possibly because of disease. These waning and waxing numbers greatly impact the animals that count on hares for food, particularly the lynx. The snowshoe hare may have up to four litters in a year which average three to eight young. Males compete for females, and females may breed with several males. Young snowshoe hares, known as leverets, are born in nests which consist of shallow depressions dug into the ground. They are born with a full coat of fur and with their eyes open, and remain concealed within dense vegetation. The female snowshoe hare visits the leverets to nurse them. Hares greatly influence the world around them, including the vegetation, predators, and other herbivores and omnivores that live in the same habitats. Hares browse heavily on vegetation. Browsing affects the growth of plants and stimulates plants to produce secondary compounds that make them unpalatable for hares and other omnivores. Predation The relationship between snowshoe hares and their year-round predators including lynx, great-horned owls, and northern goshawks is well documented. These and other predators such as golden eagles depend on snowshoe hares as a food source early in the nesting season. Across the boreal forest, the population size and reproductive success of many predators cycles with the abundance of hare. In Yukon, 30-day survival of radio-tagged leverets was 46%, 15%, and 43% for the first, second, and third litters of the year, respectively. There were no differences in mortality in plots with food added. The main proximate cause of mortality was predation by small mammals, including red squirrels (Tamiasciurus hudsonicus) and Arctic ground squirrels (Spermophilus parryii). Littermates tended to live or die together more often than by chance. Individual survival was negatively related to litter size and positively related to body size at birth. Litter size is negatively correlated with body size at birth. Snowshoe hares are experts at escaping predators. Young hares often "freeze" in their tracks when they are alerted to the presence of a predator. Presumably, they are attempting to escape notice by being cryptic. Given the hare's background-matching coloration, this strategy is quite effective. Older hares are more likely to escape predators by fleeing. At top speed, a snowshoe hare can travel up to 27 mile per hour. An adult hare can cover up to 10 feet in a single bound. In addition to high speeds, hares employ skillful changes in direction and vertical leaps, which may cause a predator to misjudge the exact position of the animal from one moment to the next. Important predators of snowshoe hares include gray foxes, red foxes, coyotes, wolves, lynx, bobcats and mink. Predators The snowshoe hare is a major prey item for a number of predators. Major predators include Canada lynx (Lynx canadensis), bobcats (L. rufus), fishers (Martes pennanti), American martens (M. americana), long-tailed weasels (Mustela frenata), minks (M. vison), foxes (Vulpes and Urocyon spp.), coyote (Canis latrans), domestic dogs (C. familiaris), domestic cats (Felis catus), wolves (C. lupus), mountain lions (Felis concolor), great horned owls (Bubo virginianus), barred owls (Strix varia), spotted owls (S. occidentalis), other owls, red-tailed hawks (Buteo jamaicensis), northern goshawks (Accipiter gentilis), other hawks (Buteonidae), golden eagles (Aquila chryseatos), and crows and ravens. Other predators include black bears (Ursus americanus). In Glacier National Park snowshoe hares are a prey item of Rocky Mountain wolves (Canis lupus irremotus). A major predator of the snowshoe hare is the Canadian lynx. Historical records of animals caught by fur hunters over hundreds of years show the lynx and hare numbers rising and falling in a cycle, which has made the hare known to biology students worldwide as a case study of the relationship between numbers of predators and their prey. Northern populations of snowshoe hares undergo cycles that range from seven to 17 years between population peaks. The average time between peaks is approximately 10 years. The period of abundance usually lasts for two to five years, followed by a population decline to lower numbers or local scarcity. Areas of great abundance tend to be scattered. Populations do not peak simultaneously in all areas, although a great deal of synchronicity occurs in northern latitudes. From 1931 to 1948, the cycle was synchronized within one or two years over most of Canada and Alaska, despite differences in predators and food supplies. In central Alberta, low snowshoe hare density occurred in 1965, with 42 to 74 snowshoe hares per 100 acres (40 ha). The population peak occurred in November 1970 with 2,830 to 5,660 snowshoe hares per 100 acres (40 ha). In the southern parts of its range, snowshoe hare populations do not fluctuate radically. As well as being prey to a number of forest animals, the snowshoe hare is hunted mainly for food by humans, particularly in Canada. Habitat loss and fragmentation, and possibly climate change, also threaten populations of the snowshoe hare. Clear-cutting of forests, whereby most or all of the trees in an area are cut down, reduces the area of ideal habitat for the snowshoe hare, which tends not to venture into open areas. The hares reach maturity after one year. Many hares do not live this long. But some hares can live as long as five years in the wild. Snowshoe hare conservation Although the snowshoe hare currently has a stable population trend and is not currently considered to be threatened, there are some conservation strategies in place for this species. In order to increase populations of the snowshoe hare in some southern states, hunting has been banned either permanently or temporarily, although it is not certain how effective this has been. In some areas, snowshoe hares have been bred in captivity and introduced to the wild in order to artificially boost populations. However, this has not been overly successful as many of these hares die during transport, and those that are introduced to the habitat are extremely susceptible to predation. Predator control has been suggested as a means of reducing mortality in the snowshoe hare, but this method produces several challenges for conservationists. Further research into various aspects of the snowshoe hare’s ecology has been recommended, as well as long-term monitoring of the species’ population trends, and studies on the impact of specific forestry management. In addition, the snowshoe hare occurs in several U.S. National Wildlife Refuges (NWR), including Koyukuk NWR, Red Rock Lakes NWR and Kodiak NWR, which are likely to afford it some protection. Snowshoe hares have been widely studied. One of the more interesting things known about hares are the dramatic population cycles that they undergo. Population densities can vary from 1 to 10,000 hares per square mile. The amplitude of the population fluctuations varies across the geographic range. It is greatest in northwestern Canada, and least in the rocky Mountain region of the United States, perhaps because there is more biological diversity in more southerly regions. The lack of diversity in the Northwestern portion of the hare's range means that there are fewer links in the food chain, and therefore fewer species to buffer either dramatic population increases or decreases. Disease may play a part in population fluctuation. Pneumonococcus, ringworm, and salmonella have all been associated with population crashes. Snowshoe hares are also famous for their seasonal molts. In the summer, the coat of the hare is reddish brown or gray, but during the winter, the coat is snowy white. The molt usually takes about 72 days to reach completion, and it seems to be regulated by day-length. Interestingly, there seem to be two entirely different sets of hair follicles, which give rise to white and brown hairs, respectively. In the wild as much as 85% of snowshoe hares do not live longer than one year. Individuals may live up to 5 years in the wild. Economic Importance for Humans: Positive Snowshoe hares are utilized widely as a source of wild meat. In addition to this, they are an important prey species for many predators whose furs are highly valued. https://www.nationalgeographic.com/animals/mammals/s/snowshoe-hare/ https://en.wikipedia.org/wiki/Snowshoe_hare https://www.nwf.org/Educational-Resources/Wildlife-Guide/Mammals/Snowshoe-Hare http://www.iucn.org/about/work/programmes/species/who_we_are/ssc_specialist_groups_and_red_list_authorities_directory/mammals/lagomorph_specialist_group/ https://www.arkive.org/snowshoe-hare/lepus-americanus/ http://animaldiversity.org/accounts/Lepus_americanus/ https://www.esf.edu/aec/adks/mammals/snowshoe_hare.htm https://www.denali.org/denalis-natural-history/snowshoe-hare/ https://www.nps.gov/articles/snowshoe-hare.htm Snoring and Nasal Obstruction in Rabbits Did you know rabbits snore? Even occurring while they are awake, it is generally a result of blockage in the animal's airway. Typically referred to as stertor and stridor, it can also occur if nasal tissues are weak or flaccid or from excessive fluid in the passages. Symptoms The symptoms, signs and types of stertor and stridor depend on the underlying cause and severity of the condition. For example, an extremely stressed rabbit or a rabbit with a lowered immune system may sound excessively hoarse while breathing. Other typical signs for rabbits suffering from stertor and stridor include: Sneezing Rapid or loud wheezing sounds during breathing Nasal discharge (sometimes due to sinusitis or rhinitis) Discharge from the eyes Lack of appetite Inability to chew or swallow Oral abscesses (especially in the teeth) Causes Rabbits tend to be nasal breathers and any physical deformity or unusual nasal structure can result in a lower-pitched (stertor) or higher-pitched (stridor) sound emanating from the airway or nose. There are, however, many other causes for stertor and stridor in rabbits. These include: Sinusitis and rhinitis Abscesses, elongated teeth or secondary bacterial infections Facial, nasal or other trauma affecting this region, including bites from other insects or animals Allergies and irritants including inhaling pollen, dust or other insects Tumors that lodge in the airway Dysfunction of the neuromuscular system, which may include hypothyroidism or diseases affecting the brainstem Swelling and edema in the upper respiratory system Inflammation of the soft palate or throat and voice box Anxiety or stress Diagnosis To diagnose the animal, a veterinarian will first determine where the sounds are originating from in the rabbit. They will then conduct various lab tests, including X-rays, which are used to explore the rabbit's nasal cavity and identify any facial abnormalities or signs of abscesses and bacterial infections, such as Pasteurella. Other procedures may include collecting cultures Treatment includes providing supplemental oxygen to the rabbit, when appropriate, and providing a quite, cool and calm environment in which to live. A rabbit must also have a clear and unobstructed airway, keeping its ear and nasal cavities clean and debris-free. To combat harmful bacterial infections from developing, the veterinarian may alter the rabbit's diet to include more leafy greens. Medications which are helpful to control bacterial sinusitis, rhinitis or other related infection include antibiotics. And while steroids may be used to reduce nasal swelling or inflammation, it can worsen bacterial infections and should only be used when absolutely necessary and under the direct care of a trained veterinarian. Living and Management Because stertor and stridor are often related to airway obstructions, there are many serious complications which may arise. Pulmonary edema, or fluid retention in the lungs or airway, is one such common example. It is, therefore, important to closely monitor the rabbit and bring it to the veterinarian's office for regular checkups and follow-up care during recovery. https://www.petmd.com/rabbit/conditions/nose/c_rb_stertor_stridor The Shot Hare Wales Beti Ifan was one of the witches of Bedd Gelert. Her fear had fallen upon nearly all the inhabitants, so that she was refused nothing by any one, for she had the reputation of being able to handle ghosts, and to curse people and their possessions. She therefore lived in comfort and ease, doing nothing except keeping her house moderately clean, and leaning on the lower half of her front door knitting and watching passers-by. But there was one man in the village, a cobbler and a skilled poacher, who feared neither Beti Ifan nor any other old hag of the kind. His great hobby was to tease and annoy the old woman by showing her a hare or a wild duck, and asking her if she would like to get it. When she replied she would, he used to hand it almost within her reach and then pull it back, and walk away. She could not do him much harm, as he had a birthmark above his breast; but she contrived a way by which she could have her revenge on him. She used to transform herself into a wild duck or hare, and continually appear before him on the meadows and among the trees whenever he went out poaching, but took good care to keep outside the reach of the gun. He, being a good shot, and finding himself missing so frequently, began to suspect something to be amiss. He knew of a doctor who was a "skilled man" living not far away, so he went to consult him. The doctor told him, "Next time you go out take with you a small branch of mountain ash, and a bit of vervain and place it under the stock of the gun." Then giving him a piece of paper with some writing on, he said, "When you see the hare, or any other creature of which you have some doubt, read this backward, and if it is old Beti you will see her in her own form, though she retain her assumed form; shoot at her legs, but mind you do not shoot her anywhere else." The next day, as he was working his way through a grove near Beti's house, he could see a large hare hopping in front of him. He drew out his paper and read as he was instructed; he then fired at her legs, and the hare ran towards Beti's cottage. He ran after it, and was just in time to see the hare jumping over the lower half of the house door. Going up to the cottage he could hear the old woman groaning; when he went in she was sitting by the fire with blood streaming from her legs. He was never again troubled with the hare-like appearances of old Beti'r Fedw. https://www.pitt.edu/~dash/type3055.html#haas © Copyrighted
This episode: Figuring out the best way to study the spread of a fungus that kills an invasive tree-eating caterpillar pest! Download Episode (8.2 MB, 8.9 minutes) Show notes: Microbe of the episode: Pasteurella aerogenes News item Journal Paper: Bittner TD, Hajek AE, Liebhold AM, Thistle H. 2017. Modification of a Pollen Trap Design To Capture Airborne Conidia of Entomophaga maimaiga and Detection of Conidia by Quantitative PCR. Appl Environ Microbiol 83:e00724-17. Other interesting stories: Studying the whale microbiome Gut bacteria help herbivorous ants get enough nitrogen Environment factors can affect our microbes apart from genetic factors Fiber could encourage gut microbes to help with type 2 diabetes Gut microbes can affect parasitic worm infections Email questions or comments to bacteriofiles at gmail dot com. Thanks for listening! Subscribe: iTunes, RSS, Google Play. Support the show at Patreon, or check out the show at Twitter or Facebook
This episode covers Chapter 61 of Rosen’s Emergency Medicine. Know anything about mammalian bites...? Yeah, neither did we until we read this chapter. Lots of juicy clinical pearls. List 5 pathogens responsible for infection from Dog bite List 4 risk factors for overwhelming sepsis from dog bite What first line antibiotic is a good choice for cat and dog bites? What species are known to cause infection with Pasteurella multocida? What are the risk factors for infection with animal bites? Describe the treatment of Monkey Bites? When is anti-viral prophylaxis NOT indicated for a monkey bite What is the duration of therapy of antiviral prophylaxis? Describe the recommendations for wound closure and antibiotics in bite cases Wisecracks: What about seal bites? What about rabies in BC? Waterhouse-Friderichsen syndrome & capnocytophagia-related Gangrene sepsis - what are they?
This episode covers Chapter 61 of Rosen’s Emergency Medicine. Know anything about mammalian bites...? Yeah, neither did we until we read this chapter. Lots of juicy clinical pearls. List 5 pathogens responsible for infection from Dog bite List 4 risk factors for overwhelming sepsis from dog bite What first line antibiotic is a good choice for cat and dog bites? What species are known to cause infection with Pasteurella multocida? What are the risk factors for infection with animal bites? Describe the treatment of Monkey Bites? When is anti-viral prophylaxis NOT indicated for a monkey bite What is the duration of therapy of antiviral prophylaxis? Describe the recommendations for wound closure and antibiotics in bite cases Wisecracks: What about seal bites? What about rabies in BC? Waterhouse-Friderichsen syndrome & capnocytophagia-related Gangrene sepsis - what are they?
Tierärztliche Fakultät - Digitale Hochschulschriften der LMU - Teil 07/07
Im Rahmen der vorliegenden Arbeit wurde das Vorkommen von Bakterien im unteren Respirationstrakt von Hunden mit Atemwegserkrankungen und deren Resistenzverhalten gegenüber klinisch relevanten Antibiotika untersucht. Hierfür wurden die Ergebnisse der bakteriologischen Untersuchungen und Resistenztests von 502 Proben von 493 Hunden retrospektiv ausgewertet, die im Zeitraum von 1989 bis 2011 an der Medizinischen Kleintierklinik der Ludwig-Maximilians-Universität München mit respiratorischen Symptomen vorgestellt wurden. Aerobe Bakterien wurden aus 65 % der Proben isoliert, wobei in 47 % der positiven Kulturen mehrere Isolate nachgewiesen wurden. Grampositive Bakterien wurden aus 52 % und gramnegative Bakterien aus 77 % der Proben mit bakteriellem Wachstum kultiviert. Die häufigsten Isolate umfassten Spezies der Gattungen Streptococcus (31 %), Staphylococcus (19 %), Pasteurella (16 %) und Pseudomonas (14 %). Weiterhin konnten Enterobakterien in 30 % der positiven Proben nachgewiesen werden, bei denen es sich in der Hälfte der Fälle um Escherichia coli (15 %) handelte. Bordetella bronchiseptica als primär pathogenes Bakterium wurde in 8 % der positiven Fälle vergleichsweise selten isoliert. Im zweiten Teil der Arbeit wurde anhand der Ergebnisse des Agardiffusionstests die in-vitro-Sensibilität der häufigsten bakteriellen Isolate gegenüber den antibiotischen Wirkstoffen Enrofloxacin, Gentamicin, Cefalexin/Cefalotin, Amoxicillin-Clavulansäure, Sulfonamid/Trimethoprim, Cefotaxim, Doxycyclin und Ampicillin ausgewertet. Enrofloxacin zeigte die höchste Gesamtwirksamkeit aller getesteten antibiotischen Wirkstoffe gegenüber 86 % aller Keime, darunter 87 % der gramnegativen Isolate. Hochwirksam gegenüber grampositiven Bakterien erwiesen sich Amoxicillin-Clavulansäure (92 %) und Cephalosporine der ersten Generation (86 %), wobei 40 % der gramnegativen Isolate resistent gegenüber diesen Wirkstoffen waren. Ausgedehnte Resistenzen zeigten sich vor allem unter gramnegativen Spezies gegenüber Beta-Laktam-Antibiotika, potenzierten Sulfonamiden und Doxycyclin. Sehr hohe Resistenzraten wurden für Escherichia coli und Pseudomonas spp. nachgewiesen. Lediglich Enrofloxacin und Gentamicin wiesen eine Wirksamkeit gegenüber 70 bis 73 % dieser Isolate auf. Am empfänglichsten zeigten sich Pasteurella spp. mit weniger als 15 % Resistenzen gegenüber den meisten Antibiotika. Eine günstige Resistenzlage konnte auch für Bordetella bronchiseptica nachgewiesen werden. Hier lagen über 90 % sensible Isolate gegenüber Enrofloxacin, Gentamicin, Amoxicillin-Clavulansäure und Doxycyclin vor. Im Verlauf des Studienzeitraums konnte eine signifikante Abnahme der in-vitro-Wirksamkeit von Enrofloxacin gezeigt werden. Insbesondere für Escherichia coli konnte in der zweiten Hälfte des Untersuchungszeitraums ein signifikanter Anstieg des Anteils Enrofloxacin-resistenter Isolate nachgewiesen werden. Die Ergebnisse der vorliegenden Untersuchung unterstreichen aufgrund des nicht exakt vorhersehbaren Resistenzverhaltens der isolierten Bakterien die Notwendigkeit zur routinemäßigen Durchführung von bakteriologischen Untersuchungen und antibiotischen Resistenztests bei Hunden mit bakteriellen Atemwegsinfektionen. Anhand der erhobenen Daten kann Enrofloxacin zur empirischen antibiotischen Behandlung oder zur Initialen Therapie bis zum Vorliegen der Ergebnisse aus Erregerkultivierung und Resistenztests bei Infektionen mit gramnegativen oder unbekannten Erregern eingesetzt werden, während Amoxicillin-Clavulansäure zur Behandlung von Infektionen mit grampositiven Bakterien geeignet erscheint.
Medizinische Fakultät - Digitale Hochschulschriften der LMU - Teil 01/19
Ziel der Arbeit war es, die molekularen Mechanismen zu erforschen, durch die das Pasteurella multocida Toxin zu einer Aktivierung von Endothelzellen mit anschließender Störung der Barrierefunktion des Endothels führt. Dafür wurden humane Endothelzellen (HUVEC) verwendet, die für Permeabilitätsmessungen auf Porenmembranen bis zur Entstehung eines dichten Monolayers kultiviert wurden. Als Maß für die endotheliale Permeabilität wurde die Durchlässigkeit des endothelialen Monolayers für Meerrettichperoxidase verwendet. Zur Sichtbarmachung des endothelialen Zytoskeletts wurden die Zellen mit Rhodamin Phalloidin gefärbt und im Fluoreszenzmikroskop analysiert. Mit Hilfe spezifischer Hemmstoffe, die teilweise in die Zellen mikroinjiziert wurden, sowie der biochemischen Messung von Enzymaktivitäten bzw. Phosphorylierung, erhielten wir folgenden Ergebnisse: 1. Das Pasteurella multocida Toxin führt zu einer Erhöhung der Permeabilität des endothelialen Monolayers über einen Rho-GTPase-abhängigen Signalweg. 2. Die Stimulierung der Endothelzellen mit dem Pasteurella multocida Toxin führt zur massiven Bildung von Aktinstreßfasern, die von Rho, seinem Zielprotein der Rho-Kinase als auch von der MLC-Phosphatase abhängig sind. Diese morphologischen Veränderungen stellen vermutlich die Basis für die Erhöhung der endothelialen Permeabilität dar. 3. Pasteurella mulocida Toxin führt über Rho und mit großer Wahrscheinlichkeit auch über die Rho-Kinase zu einer Inaktivierung der MLCPhosphatase mit anschließender Erhöhung der MLC-Phosphorylierung. Als Ergebnis unserer Arbeiten ergibt sich ein Signalweg, in dessen Zentrum die GTPase Rho steht und dessen Details noch einmal in der Abbildung 7-1 zusammengefaßt werden.