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991.
992.
植酸酶是一种功能强大的酶,能够使无法消化利用的饲料释放出大量的养分。 但当植酸酶使用不当时,那些养分将不能被释放出和/或被动物机体所获取。如果那样,植酸酶的投入成本和价值就将被浪费了。  相似文献   
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Knowledge about the patterns of animal movement – particularly feeder-cattle movement – within the USA is necessary in order to anticipate how diseases might be spread geographically. This study was conducted to explore the availability of interstate-level movement data which might be used to develop a more coherent national picture of interstate feeder-cattle movement. State Statistical Offices of the National Agricultural Statistics Service, 1996 (NASS) and Departments of Agriculture in all 50 states were contacted to determine the type of information collected regarding the import and export of feeder cattle. Eighteen of the 50 states contacted recorded updated import and export information by using certificates of veterinary inspection and (occasionally) entry permits for verification. The 18 states were: Alabama, Colorado, Florida, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Maryland, Massachusetts, Minnesota, New Jersey, Pennsylvania, Texas, West Virginia, Wisconsin, and Wyoming. Profiles of import and export data from Kansas, Texas, Colorado and Iowa (the primary receivers of 51% of total 1995 imports) were developed. These four states received at least 50% of their cattle imports from <9 different states. As a result, approximately half of the nation's import movement can be explained by a total of 13 states and Mexico (excluding duplicates). Also, >50% of the exports from Kansas, Texas, Colorado, and Iowa go to ≤3 states. This import and export information confirms conclusions of others that cattle tend to move toward the center of the USA. However, if more states kept comprehensive, up-to-date records of movement information, knowledge about cattle-movement patterns in the USA would be importantly increased. The lack of specific notations on certificates of veterinary inspection can lead only to perceived trends; the present records have limited value in tracking animal movement.  相似文献   
995.
CASE: A 13-week-old female boxer pup was found to be suffering from rigidity of the left hindleg. Antibiotic and anti-inflammatory treatment over a 3-week period failed to improve the condition and the pup was humanely killed. METHODS: Serological examination for Neospora antibodies was carried out by the indirect fluorescent antibody test and for Toxoplasma gondii antibodies with a latex agglutination test. A variety of tissues were examined histologically, and the central nervous system by immunohistochemistry and the polymerase chain reaction. RESULTS: The IFAT for anti-Neospora antibodies showed a titre of 1:51 200 in the clinically affected pup while the latex agglutination test for Toxoplasma antibodies was negative. The dam and one of two tested litter-mates had anti-Neospora IFAT titres of 1:1600, the other litter mate was negative. All three were not clinically affected. Histological, immunohistochemical and polymerase chain reaction examinations of the affected pup confirmed the diagnosis of Neospora infection. CONCLUSION: In the live animal, serological examination is thought to be the most useful specific test. Post-mortem examination by traditional histology, immunohistochemistry and the polymerase chain reaction confirmed the diagnosis. The case is discussed in the context of present knowledge about Neospora infection in New Zealand.  相似文献   
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Ameloblastoma is a locally aggressive odontogenic tumour that occurs in humans and dogs. Most ameloblastomas (AM) in humans harbour mutually‐exclusive driving mutations in BRAF, HRAS, KRAS, NRAS or FGFR2 that activate MAPK signalling, and in SMO that activates Hedgehog signalling. The remarkable clinical and histological similarities between canine acanthomatous ameloblastoma (CAA) and AM suggest they may harbour similar driving mutations. In this study, aimed at characterizing the mutational status of SMO, BRAF, HRAS, KRAS, NRAS and FGFR2 in CAA, we used RNA sequencing, Sanger sequencing and restriction fragment length polymorphism assays to demonstrate that 94% of CAA (n = 16) harbour a somatic HRAS p.Q61R mutation. The similarities in MAPK‐activating mutational profiles between CAA and AM implicate conserved molecular mechanisms of tumorigenesis, thus, qualifying the dog as a potentially useful model of disease. Given the relevance of RAS mutations in the pathogenesis of odontogenic tumours and other types of cancer, the results of this study are of comparative, translational, and veterinary value.  相似文献   
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