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91.
Cross-protective properties of infectious bursal disease viruses (IBDVs) were studied. Viruses represented different subtypes of serotype 1, including recently isolated viruses (variants), and a serotype 2 virus. Chickens were vaccinated at 3 weeks of age with inactivated vaccines containing 10(5), 10(6), 10(7), or 10(8) mean tissue-culture infectious dose of a given virus and challenged 2 weeks later using either 10(2) or 10(3.5) mean embryo infectious dose (EID50) of either a standard virus or a variant serotype 1 virus. Protection was evaluated at 5 and 10 days post-challenge, based on gross and microscopic lesions, body weight, and bursa/body-weight ratios. The serotype 2 virus did not confer protection on birds challenged with the serotype 1 viruses. Vaccines made of variant viruses at the low doses protected chickens challenged with the high or low doses of either the standard or the variant viruses. Vaccines made of the standard or variant strains at low doses protected against high or low challenge doses of the standard strain. Vaccines made of the high dose of any of the standard strains protected chickens against the variant virus when the low challenge dose (10(2) EID50) was used, but not when the high challenge dose (10(3.5) EID50) was used. The lowest dose of the standard viruses vaccines required to confer protection against the variant virus varied depending on the strain. Results indicated that protection depended on the strain and dose of both the vaccine and challenge viruses and that the variant strains and standard strains share a common protective antigen(s).  相似文献   
92.
93.
This paper describes an insulinoma in 2 guinea pigs (Cavia porcellus). Both guinea pigs presented with neurologic signs and low blood glucose readings. The neurologic signs resolved with dextrose administration. Insulinoma was confirmed on postmortem examination.  相似文献   
94.
A 3-year-old Texas Longhorn steer had a long history of progressive swelling of the soft tissues of the jaw and neck. At necropsy, multifocal to coalescing dermal and subcutaneous pyogranulomas were surrounded by fibrous tissue. Microscopically, the pyogranulomas contained aggregates of gram-negative coccobacilli surrounded by Splendore-Hoeppli material and were separated by bands of fibrovascular tissue (botryomycosis). Phylogenetic analysis of multilocus sequence-typing data revealed that the bacteria recovered in pure culture from swabs of submandibular tissue were most closely related to Bibersteinia [Pasteurella] trehalosi. The bacterial colonies were immunohistochemically reactive with a rabbit polyclonal anti-Pasteurella class C acid phosphatase antibody. Botryomycosis is a pyogranulomatous inflammation caused by a variety of nonbranching, nonfilamentous bacteria that elicit the formation of Splendore-Hoeppli material. This case of botryomycosis is unique for its association with Bibersteinia trehalosi.  相似文献   
95.
96.
Canine adenovirus type 1 infection of a Eurasian river otter (Lutra lutra)   总被引:1,自引:0,他引:1  
A 10-year-old female Eurasian river otter (Lutra lutra) died after prolonged anorexia and weight loss in the Seoul Grand Park Zoo, Seoul, Republic of Korea. On necropsy, the liver was found to be swollen and friable with 1 lobe enlarged and necrotic. The other organs showed no significant alterations except for mild atrophy of the right kidney. Microscopically, there was multifocal hepatic necrosis. The hepatocytes around the necrotic areas were swollen and contained large basophilic intranuclear inclusions. Periportal infiltration by plasma cells and lymphocytes was also evident. Transmission electron microscopy revealed characteristic hexagonal virus particles sized approximately 70 nm in diameter in the nuclei of the hepatocytes, which were consistent with an adenovirus. Polymerase chain reaction of the formalin-fixed, paraffin-embedded liver sections was used to determine whether the virus was either the canine adenovirus type 1 (CAV-1), canine adenovirus type 2 (CAV-2), or some other viral agent. The results of these tests showed that the virus was CAV-1. To our knowledge, this is the first report on a CAV-1 infection in an otter.  相似文献   
97.
A ventral abdominal subcutaneous mass was removed from each of 2 young adult spayed female ferrets. In both cases, the neoplasms were composed of islands of polygonal cells separated by interlacing streams of spindloid cells reminiscent of ferret adrenocortical tumors with smooth muscle proliferation. Immunohistochemically, the polygonal cells demonstrated strong cytoplasmic reactivity for inhibin and weak cytoplasmic reactivity for pancytokeratin and S-100 protein. Spindloid cells demonstrated strong cytoplasmic reactivity for alpha smooth muscle actin, muscle-specific actin, desmin, and glial fibrillary acidic [corrected] protein. Ultrastructurally, the polygonal cells contained numerous intracytoplasmic clear vacuoles, mitochondria, scant rough endoplasmic reticulum, and few intermediate filaments. In one tumor, vesicular tubular mitochondria were found in polygonal cells. The spindloid cells contained numerous aggregates of parallel intermediate filaments. The histologic, immunohistochemical, and ultrastructural findings are suggestive of adrenocortical tumors with smooth muscle proliferation, but cannot be differentiated from an ovarian gonadal stromal tumor. Neither ferret had a clinically detected primary adrenal gland tumor or clinical signs of adrenal-associated endocrinopathy.  相似文献   
98.
Follicle growth, oocyte quality or oocyte growing environment (follicular fluid) were evaluated in cows with severe liver damage (haemorrhage, telangiectasis, cholangitis and abscess) that were visually diagnosed at the slaughterhouse. Holstein cows aged 40–90 months with either a healthy liver (HL cow) or damaged liver (DL cow) were selected as donors. Follicle development kinetics was evaluated by counting the follicles at various developmental stages. In addition, the biochemical characteristics of the follicular fluids, developmental competence of preantral follicles cultured for 16 days in vitro and the ability of oocytes to develop to the blastocyst stage 8 days after fertilization were examined. DL cows had fewer secondary follicles than HL cows, and the correlation between the number of secondary follicles and the number of primary follicles differed among DL and HL cows. The follicular fluid of DL cows contained significantly lower levels of albumin and a higher total protein content than that of HL cows. Oocyte nuclear maturation assessed at 5, 16 and 21 h after beginning of culture was slower in DL cows than in HL cows, although the final maturation rates did not differ. The rate of polyspermic fertilization was significantly higher and the proportion of cleavage at 48 h after insemination and blastulation lower in DL cows compared with HL cows. When preantral follicles were cultured in vitro, the rate of follicles with normal morphology was lower in DL cows than in HL cows. These findings suggest that the kinetics of folliculogenesis differ among DL and HL cows and the developmental ability of preantral follicles and oocytes is lower in DL cows than in HL cows.  相似文献   
99.
Background: Obese people with heart failure have improved survival compared with their normal or underweight counterparts. The purpose of this study was to determine if there is a relationship between body weight or body condition and survival in cats with heart failure. Hypothesis: Body weight and body condition score (BCS) are predictors of survival in cats with heart failure. Animals: One‐hundred and one cats with heart failure (International Small Animal Cardiac Health Council Classes II, IIIa, or IIIb) evaluated between March 2007 and June 2009. Methods: Data regarding initial body weight and BCS, subsequent changes in body weight, and treatment were collected from records and compared with survival times. Results: Median initial body weight was 5.1 kg (range, 2.2–9.5 kg). Median BCS was 5 (range, 3–9). Of the 68 cats that were discharged from the hospital, median body weight change was 0.0 kg (range, ?2.6 to +2.3 kg). Survival time for all 101 cats was 93 days (0–811 days). Survival could be predicted using a model combining initial body weight (P= .02), body weight squared (P= .02), and survival to discharge (P < .001) with a resulting global P value for this model of P < .0001. Conclusions and Clinical Importance: Cats with the lowest and highest body weights had reduced survival times compared with those with body weights in the intermediate ranges, suggesting a U‐shaped relationship between body weight and survival. Additional research into the effects of body composition could help to determine optimal management of cats with heart failure.  相似文献   
100.
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