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41.
A late-gestation jill was presented for depression, anorexia, and weakness. The working diagnosis became pregnancy toxemia. Supportive care was initiated and an emergency cesarian section performed. Twelve live kits were delivered; however, all soon perished despite home care. Surgery and recovery are discussed, including information regarding pregnancy toxemia in general. 相似文献
42.
Pilgram M van Santen E Geers M 《Tijdschrift voor diergeneeskunde》2004,129(16):535; author reply 535-535; author reply 536
43.
Czuprynski CJ Leite F Sylte M Kuckleburg C Schultz R Inzana T Behling-Kelly E Corbeil L 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2004,5(2):277-282
Progress in producing improved vaccines against bacterial diseases of cattle is limited by an incomplete understanding of the pathogenesis of these agents. Our group has been involved in investigations of two members of the family Pasteurellaceae, Mannheimia haemolytica and Haemophilus somnus, which illustrate some of the complexities that must be confronted. Susceptibility to M. haemolytica is greatly increased during active viral respiratory infection, resulting in rapid onset of a severe and even lethal pleuropneumonia. Despite years of investigation, understanding of the mechanisms underlying this viral-bacterial synergism is incomplete. We have investigated the hypothesis that active viral infection increases the susceptibility of bovine leukocytes to the M. haemolytica leukotoxin by increasing the expression of or activating the beta2 integrin CD11a/CD18 (LFA-1) on the leukocyte surface. In vitro exposure to proinflammatory cytokines (i.e. interleukin-1beta, tumor necrosis factor-alpha and interferon-gamma) increases LFA-1 expression on bovine leukocytes, which in turn correlates with increased binding and responsiveness to the leukotoxin. Alveolar macrophages and peripheral blood leukocytes from cattle with active bovine herpesvirus-1 (BVH-1) infection are more susceptible to the lethal effects of the leukotoxin ex vivo than leukocytes from uninfected cattle. Likewise, in vitro incubation of bovine leukocytes with bovine herpesvirus 1 (BHV-1) potentiates LFA-1 expression and makes the cells more responsive to leukotoxin. A striking characteristic of H. somnus infection is its propensity to cause vasculitis. We have shown that H. somnus and its lipo-oligosaccharide (LOS) trigger caspase activation and apoptosis in bovine endothelial cells in vitro. This effect is associated with the production of reactive oxygen and nitrogen intermediates, and is amplified in the presence of platelets. The adverse effects of H. somnus LOS are mediated in part by activation of endothelial cell purinergic receptors such as P2X7. Further dissection of the pathways that lead to endothelial cell damage in response to H. somnus might help in the development of new preventive or therapeutic regimens. A more thorough understanding of M. haemolytica and H. somnus virulence factors and their interactions with the host might identify new targets for prevention of bovine respiratory disease. 相似文献
44.
Tolar EL Hendrix DV Rohrbach BW Plummer CE Brooks DE Gelatt KN 《Journal of the American Veterinary Medical Association》2006,228(1):80-85
OBJECTIVE: To evaluate clinical characteristics and breeds affected with bacterial keratitis and compare patterns of resistance in bacterial isolates over time in dogs. DESIGN: Retrospective cross-sectional study. ANIMALS: 97 dogs with bacterial keratitis. PROCEDURE: Dogs with bacterial keratitis were identified from teaching hospital medical records at the Universities of Tennessee and Florida during the years 1993 to 2003. Data were collected pertaining to breed, Schirmer tear test results, treatments administered at the time of initial examination, bacterial species isolated, and resistance to selected antimicrobials. RESULTS: 66% of the dogs were brachycephalic, 54% had tear production < 15 mm/min, and 29% were receiving a corticosteroid at the time of initial examination. The most common bacteria isolated were Staphylococcus intermedius (29%), beta-hemolytic Streptococcus spp (17%), and Pseudomonas aeruginosa (21%). Staphylococcus intermedius isolates had limited resistance to certain antimicrobials. More than 80% of beta-hemolytic Streptococcus spp isolates were resistant to neomycin, polymyxin B, and tobramycin. Isolates of P aeruginosa were susceptible to tobramycin and gentamicin and had limited resistance to ciprofloxacin and enrofloxacin. Among bacterial species isolated, there was no evidence of development of antimicrobial resistance over time. CONCLUSIONS AND CLINICAL RELEVANCE: Data suggested that administration of ciprofloxacin or a combination of a first-generation cephalosporin and tobramycin may be used in the treatment of bacterial keratitis while awaiting results of bacterial culture and susceptibility testing. Evidence suggests that current methods of medical management of bacterial keratitis are not associated with increased antimicrobial resistance. 相似文献
45.
In order to develop better control measures against avian influenza, it is necessary to understand how the virus transmits in poultry. In a previous study in which the infectivity and transmissibility of the pandemic H1N1 influenza virus was examined in different poultry species, we found that no or minimal infection occurred in chicken and turkeys intranasally (IN) inoculated with the virus. However, we demonstrated that the virus can infect laying turkey hens by the intracloacal (IC) and intraoviduct (IO) routes, possibly explaining the drops in egg production observed in turkey breeder farms affected by the virus. Such novel routes of exposure have not been previously examined in chickens and could also explain outbreaks of low pathogenicity avian influenza (LPAI) that cause a decrease in egg production in chicken layers and breeders. In the present study, 46-wk-old specific-pathogen-free chicken layers were infected by the IN, IC, or IO routes with one of two LPAI viruses: a poultry origin virus, A/chicken/CA/1255/02 (H6N2), and a live bird market isolate, A/chicken/NJ/12220/97 (H9N2). Only hens IN inoculated with the H6N2 virus presented mild clinical signs consisting of depression and anorexia. However, a decrease in number of eggs laid was observed in all virus-inoculated groups when compared to control hens. Evidence of infection was found in all chickens inoculated with the H6N2 virus by any of the three routes and the virus transmitted to contact hens. On the other hand, only one or two hens from each of the groups inoculated with the H9N2 virus shed detectable levels of virus, or seroconverted and did not transmit the virus to contacts, regardless of the route of inoculation. In conclusion, LPAI viruses can also infect chickens through other routes besides the IN route, which is considered the natural route of exposure. However, as seen with the H9N2 virus, the infectivity of the virus did not increase when given by these alternate routes. 相似文献
46.
47.
48.
Roupie V Viart S Leroy B Romano M Trinchero N Govaerts M Letesson JJ Wattiez R Huygen K 《Veterinary immunology and immunopathology》2012,145(1-2):74-85
Mycobacterium avium subsp. paratuberculosis (Map), the etiological agent of chronic enteritis of the small intestine in domestic and wild ruminants, causes substantial losses to livestock industry. Control of this disease is seriously hampered by the lack of adequate diagnostic tools and vaccines. Here we report on the immunogenicity of eight Map specific antigens, i.e. MAP1693c, Ag3, MAP2677c (identified by post-genomic and immunoproteomic analysis of Map secretome) and Ag5, Ag6, MAP1637c, MAP0388 and MAP3743 (identified by bioinformatic in silico screening of the Map genome). Strong, antigen-specific IFN-γ responses were induced in mice vaccinated with plasmid DNA encoding MAP1693c, MAP1637c, MAP0388 and MAP3743. In contrast, T cell responses in Map infected mice were directed preferentially against Ag5 and to a lesser extent against MAP3743. None of the tested DNA vaccines conferred protection against subsequent challenge with Map. 相似文献
49.
Mutinelli F Vercelli A Carminato A Luchesa L Pasolli C Cova M Marchioro W Melchiotti E Vascellari M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(4):527-529
A free-living European red deer calf (Cervus elaphus) was euthanized due to bilateral microphthalmia. Lens was missing, replaced by proliferating squamous epithelial cells; hyperplastic squamous cells, sebaceous and mucinous glands were observed within the cornea with the characteristics of inclusion cyst. Findings were consistent with congenital microphthalmia/aphakia, with multiple eye abnormalities. 相似文献