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991.
K Fritzsche H Müller E Weiss 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1990,37(7):544-548
Variation in size of warts located on the beak of wattle-pigeons represents a dominant trait of this breed. Excessive growth to extraordinary size in two breeds (barbs and carriers), in addition to a large beak, can cause losses due to the inability of the parents to feed the offspring properly. In older birds, respiration is impeded and the field of vision is limited. This permanent growth in barbs and carriers could not be attributed neither to an infection with papovaviruses, nor to the overexpression of the retroviral c-src-protooncogen. This finding, in conjunction with the genetic analysis, underlines that this prominent trait is genetically determined. 相似文献
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Von Eva Schiffmann-Wyttenbach W. Mosimann M. König 《Anatomia, histologia, embryologia》1983,12(4):317-324
Ligh-, electronmicroscopical and histochemical examinations of the circumanal glands of adult dogs suggest that these glands take part in steroid metabolism. The glands have no excretory ducts. 相似文献
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996.
K H Hoblet W Weiss 《Veterinary Clinics of North America: Food Animal Practice》2001,17(1):111-27, vi-vii
Low-quality hoof horn is a frequent underlying cause of lameness in cattle. Because the lesions that are observed are the result of insults that affect horn production at the cellular level, the term claw horn disruption has been proposed to describe the disease process. Although claw horn disruption may result from multiple etiologies, the response of the keratinocytes is relatively nonspecific in that lesions often appear the same regardless of cause. To solve herd problems, the investigation of possible etiologies must be integrated with a basic understanding of the anatomic and physiologic features of hoof horn production. 相似文献
997.
Two types of replaceable rigid cannulas are described, one for use in the rumen of small ruminants and the other in the small intestine of growing pigs. 相似文献
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Cats are considered essential for the maintenance of Toxoplasma gondii in nature. However, T. gondii infection has been reported in arctic fox (Vulpes lagopus) from the Svalbard high arctic archipelago where felids are virtually absent. To identify the potential source of T. gondii, we attempted to isolate and genetically characterize the parasite from arctic foxes in Svalbard. Eleven foxes were trapped live in Grumant (78 degrees 11'N, 15 degrees 09'E), Svalbard, in September 2005 and 2006. One of the foxes was found to be seropositive to T. gondii by the modified agglutination test (MAT). The fox was euthanized and its heart and brain were bioassayed in mice for the isolation of T. gondii. All 10 mice inoculated with brain tissue and one of the five inoculated with heart developed MAT antibodies, and tissue cysts were found in the brains of seropositive mice. Two cats fed tissues from infected mice shed T. gondii oocysts. Genotyping using 10 PCR-RFLP markers and DNA sequencing of gene loci BSR4, GRA6, UPRT1 and UPRT2 determined the isolate to be Type II strain, the predominant T. gondii lineage in the world. 相似文献