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21.
OBJECTIVE: To determine in dogs what effect using hip conformation scores assigned by the Orthopedic Foundation for Animals (OFA) as a criterion for breeding selections would have on hip conformation scores of the progeny. DESIGN: Longitudinal study. ANIMALS: English Setters, Portuguese Water Dogs, Chinese Shar-peis, and Bernese Mountain Dogs for which OFA hip conformation scores were known. PROCEDURE: Pedigree data were obtained from the national breed clubs and the American Kennel Club and merged with data from the OFA hip conformation score database. An ANOVA was used to evaluate the effects of sex, age at the time of radiographic evaluation, and year of birth on the variation in hip conformation scores among the progeny. Heritability was estimated by use of within-year midparent offspring regression analyses. RESULTS: Significant differences in progeny hip conformation scores between sexes were not detected, but age at the time of radiographic evaluation and year of birth had a significant effect on hip joint conformation of the progeny. Estimated heritability (mean +/- SE) was 0.26 +/- 0.03, and dam and sire hip conformation scores had a significant effect on progeny hip conformation scores. Annual decreases in percentage of dysplastic progeny and increases in percentages of progeny and breeding dogs with phenotypically normal hip joint conformation were detected. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that hip conformation scores have moderate heritability in dogs and selection of breeding stock with better hip conformation scores will increase the percentage of progeny with phenotypically normal hip joint conformation.  相似文献   
22.
The diagnosis of eastern equine encephalitis (EEE) virus infection in avian species is relatively difficult when compared with other species. There are no characteristic histologic lesions in the avian brain that would serve to distinguish EEE from infections with, for example, Newcastle disease or highly pathogenic avian influenza virus. Traditionally, virus isolation (VI) and/or hemagglutination inhibition (HI) has been used for a definitive diagnosis of EEE in birds. Recently, we developed an immunohistochemistry (IHC) technique for confirmatory diagnosis of EEE infection in equine brain. This test also detected EEE virus in formalin-fixed avian brain. VI confirmed IHC finding in two cases of EEE in ring-neck pheasants. IHC is a rapid, sensitive test for confirming and differentiating a histopathologic diagnosis of EEE in avian species and should be considered as an alternative test to VI or HI.  相似文献   
23.
Newer genetic lines of pigs are being used in indoor and outdoor production systems. The objectives of Exp. 1 were to describe the effects of the maternal sow line genotype, environment (indoor vs outdoor), and the genotype x environment interactions on blood hemoglobin (Hb), immunoglobulin G (IgG) concentrations, white blood cell (WBC) numbers, lymphocyte transformation/blastogenesis (LTA), natural killer (NK) cell activity, neutrophil chemotaxis, cortisol concentrations, and leukocyte differentials. Studies were performed using two genotypes: PIC Experimental-94 (Exp-94, an experimental line containing 25% Meishan) and PIC Camborough-15 (C-15). The Exp-94 sows had lower LTA at 0.2 microg/mL mitogen than the C-15 sows, whereas Exp-94 sows had higher NK cytotoxicity than the C-15 sows. When indoors, the two genotypes showed similar neutrophil chemotaxis. When outdoors, the C-15 genotype had higher (P < .01) neutrophil chemotaxis than the Exp-94 sows. The other immune measures were statistically similar for the two genotypes for each environment and for the genotype x environment interaction of sows. Experiment 2 sought to determine the effects of genotype on the immune system of nursery-age offspring of the experimental lines. Each sow line was bred to a common PIC 405 boar line. The Exp-94 x 405 pigs had elevated WBC numbers than C-15 x 405 pigs. The social status of the Exp-94 x 405 or the C-15 x 405 pigs showed no effect on any of the immune measures studied. The other immune measures were statistically similar for the two lines of pigs. The Exp-94 line had marginally increased NK activity but reduced lymphocyte blastogenesis and neutrophil chemotaxis compared with the C-15 line.  相似文献   
24.
The medical records and follow-up data for 4 horses with fibrotic myopathy of the semitendinosus muscle treated by semitendinosus tenotomy were reviewed. The gait deficit for each of the 4 horses was typical of fibrotic myopathy. Two of the horses had the gait deficit since birth. The efficacy of semitendinosus tenotomy was compared with the traditional treatment of partial myotenectomy of the affected muscle. The functional results in the 4 horses appeared to be equal to partial myotenectomy in returning the horses to athletic function and, compared with what has been reported, was cosmetically superior.  相似文献   
25.
Bovine herpesvirus (infectious bovine rhinotracheitis virus)-infected cell antigens were solubilized with Nonidet P-40. The crude antigen extract was separated by reaction with bovine hyperimmune serum in line immunoelectrophoresis; individual immunoprecipitates were used to immunize rabbits. Rabbit sera possessing serum neutralizing activity were analyzed by reaction with crude antigen extract in immunoprecipitation sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot. Four virus-specified glycopeptides, with molecular weights of 69-75K, 77-81K, 82-92K and 108-115K, appeared to be involved in inducing serum neutralizing antibody.  相似文献   
26.
Antibodies to Aujeszky's disease virus (ADV) glycoproteins gII, gIII, and gp50 were compared using four in vitro tests. Antibodies generated by vaccination with a modified-live vaccine (MLV) were also compared. The serological assays employed were: serum neutralization test (SNT), complement facilitated serum neutralization test (C'SNT), complement-mediated cytolysis and antibody dependent cellular cytotoxicity (ADCC). Pigs were immunized with single glycoproteins twice 14 days apart, or once with the modified-live vaccine. Fourteen days after the second immunization, sera were collected. Virus neutralizing activity (SNT) was demonstrated in the sera from all pigs immunized with gp50 and in one out of three immunized with gIII. Sera from the MLV group all had neutralization titers higher than animals immunized with single glycoproteins. Addition of guinea pig complement to the serum neutralization test (i.e., C'SNT) produced an enhancement of antibody titers in all groups except the pigs immunized with gIII. The complement-mediated cytolysis test rendered antibody titers similar in magnitude for all pigs immunized with single glycoproteins, but slightly lower than values for MLV vaccinated pigs. ADCC activity was clearly displayed in sera from pigs immunized with gIII or vaccinated with MLV, whereas sera from pigs immunized with gII or gp50 had a minimal response. The results indicate that the relative efficiency of antibodies against ADV glycoproteins in protection should be considered for selecting or producing gene-deleted strains for use in vaccine production.  相似文献   
27.
28.
Bobwhite quails (Colinus virginianus) were inoculated with 10(6) mean tissue-culture infective dose of quail bronchitis virus at 1, 3, 6, or 9 weeks of age by intratracheal, intraperitoneal, or subcutaneous routes. Quails developed necrotizing tracheitis, proliferative and necrotizing bronchitis and pneumonia; multifocal necrotizing hepatitis; necrotizing splenitis, with or without hyperplasia of splenic mononuclear phagocytes; bursal lymphoid necrosis; and bursal atrophy. Lesions were more extensive and severe in quails inoculated at 1 or 3 weeks of age than in older quails. Large intranuclear inclusions, characteristic of adenovirus infection, were identified in trachea, lung, liver, and bursa of Fabricius. This is the first report of the histopathology of experimentally induced quail bronchitis.  相似文献   
29.
N. Giltrap  D. Eyre  P. Reed 《EPPO Bulletin》2009,39(2):168-170
The sale of plants for planting on the Internet and by other direct marketing methods (e.g. newspaper offers) has increased dramatically in recent years. Some companies are specialist suppliers in this area and typically with this trade small quantities of plants are sent by mail to a very large number of amateur growers scattered throughout the UK. It is often difficult for the NPPO to keep track of this activity especially when the supplier is located outside its jurisdiction. Also if problems arise with plants sold in this way, taking effective official eradicatory action can be problematic. To demonstrate the issues and problems involved, two examples that occurred in the UK in 2008 are described.  相似文献   
30.
A gray-cheeked parakeet, approximately 3 years of age, was submitted for necropsy. Clinical signs included diarrhea, decreased feed consumption, fluffing of feathers, shivering, weight loss, and limping. Necropsy revealed enlargement and pale discoloration of the spleen and intestines. The liver contained multifocal pale foci. Granulomas, some of which had necrotic centers, were present along the subserosa of the intestinal tract. Microscopic examination revealed diffuse granulomatous splenitis, enteritis, and multifocal granulomatous hepatitis. Numerous acid-fast bacteria were demonstrated in the spleen, liver, and intestine.  相似文献   
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