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1. The endogenous avian leukosis virus (ev) loci present in 9 lines of domestic fowls have been partially characterised and the average heterozygosity of the loci in each line calculated. 2. Using these data an estimate of the coefficient of inbreeding of the lines was derived; this estimate of the extent of inbreeding is compared with the mating history of the lines. 3. This method provides the first means of directly assessing the degree of inbreeding of fowl lines: assumptions implicit in the method are discussed.  相似文献   
73.
Two miniature Shetland ponies showing clinical signs of Digitalis purpurea (foxglove) poisoning were examined. One animal died shortly afterwards, but the second was treated successfully with the anti-arrhythmic agent, phenytoin, and was discharged after 16 days.  相似文献   
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In Llamas and Alpacas infestation with Fasciola hepatica or Dicrocoelium dendriticum can cause liver damage, sometimes even with lethal outcome. Once infected South American Camelids (SACs) react more sensitively to these parasites than other domestic ruminants. We report here on the pathology, parasitology, clinics and therapy of this disease. Concerning Dicrocoelium dendriticum we describe own clinical results and therapeutic outcome in addition to the pathological investigation. According to anatomic corrosion casts, the bile ducts of SACs show more similarity with the equine bile system than with the bile system of domestic ruminants.  相似文献   
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The aim of this study was to compare the development of Glasser's disease in sow-reared and colostrum-deprived piglets. Ninety piglets from a commercial pig farm in Spain were used. The farm was positive for Haemophilus parasuis. Fifty-two pigs were sow-reared (SR) and 38 were colostrum-deprived (CD) piglets. The animals were intratracheally inoculated with H. parasuis serovar 5 and sacrificed at 1, 2 and 3 days post-infection. To assess the development of disease, antibody titers, clinical signs, pathological lesions, microbiological isolation and PCR amplification were compared between the groups. Inoculation of SR pigs did not cause clinical signs or lesions of Glasser's disease. In SR pigs, H. parasuis isolation and specific PCR amplification from tissues showed a very low number of positive samples. In contrast, in CD pigs, inoculation resulted in the typical signs and lesions of Glasser's disease. Positive microbiological isolation and specific PCR products were obtained from the majority of the tissues tested, and no antibodies against H. parasuis were detected. The experimental infection using CD pigs describes a successful method to study this microorganism and confirms the important role that maternal antibodies play in protection against clinical signs and disease.  相似文献   
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