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31.
Post-mortem examinations were conducted on 950 dead and terminally ill sheep during assembly for export and during transport by sea from Fremantle, Western Australia to various Middle East ports. Causes of death were grouped into 5 major categories; inanition (deaths associated with reduced feed intake, including hypocalcaemia and hypomagnesaemia), salmonellosis (enteric and septicaemic), trauma, diseases associated with excessive feed intake (lactic acidosis and enterotoxaemia) and miscellaneous diseases (mostly of farm origin). During assembly the causes of death were salmonellosis 53.4%, miscellaneous diseases 23.8%, trauma 12.6%, inanition 10.2%, acidosis 3.9%, enterotoxaemia 3.4% and no diagnosis was made in 3.4%. During shipping the causes of death in defined populations of sheep in 5 voyages were; inanition 43.4%, salmonellosis 20.2%, trauma 10.6%, miscellaneous diseases 5.9%, enterotoxaemia 1.0% and no diagnosis was made in 19.0%. The range of mortality rates per 10,000 sheep at risk for the first 11 days at sea in 5 voyages were inanition 52.6 to 76.7, salmonellosis 7.8 to 109.8, trauma 2.1 to 17.1, miscellaneous diseases 5.9 to 17.1 and enterotoxaemia nil to 10.3. 相似文献
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OBJECTIVE: To establish hematologic and biochemical reference values for the brown pelican (Pelecanus occidentalis). ANIMALS: 31 captive, healthy, but permanently disabled pelicans and 35 wild-caught, healthy pelicans from a rehabilitation facility on the east coast of Florida. PROCEDURES: Samples of venous blood were collected from each pelican, and hematologic, plasma biochemical, and electrophoretic protein analyses were performed. Student t-tests were used to compare blood values between captive versus wild-caught, adult male versus adult female, and adult versus juvenile pelicans. RESULTS: Hematologic and electrophoretic values were similar between male and female, adult and juvenile, and captive and wild-caught pelicans. Significant sex differences existed for plasma calcium and triglyceride concentrations. Plasma concentrations of calcium, cholesterol, and CO2 content differed between captive and wild-caught adults. No significant differences were found between wild-caught adult and juvenile pelicans. CONCLUSIONS AND CLINICAL RELEVANCE: Our plasma biochemical results are similar to those of other brown pelicans and confamilial species. Additional studies on seabirds are encouraged, as age, sex, reproductive status, feeding habits, and captivity are important variables for health assessment in this and other aquatic species. 相似文献
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Specific interactions in RNA enzyme-substrate complexes 总被引:27,自引:0,他引:27
Analysis of crosslinked complexes of M1 RNA, the catalytic RNA subunit of ribonuclease P from Escherichia coli, and transfer RNA precursor substrates has led to the identification of regions in the enzyme and in the substrate that are in close physical proximity to each other. The nucleotide in M1 RNA, residue C92, which participates in a crosslink with the substrate was deleted and the resulting mutant M1 RNA was shown to cleave substrates lacking the 3' terminal CCAUCA sequence at sites several nucleotides away from the normal site of cleavage. The presence or absence of the 3' terminal CCAUCA sequence in transfer RNA precursor substrates markedly affects the way in which these substrates interact with the catalytic RNA in the enzyme-substrate complex. The contacts between wild-type M1 RNA and its substrate are in a region that resembles part of the transfer RNA "E" (exit) site in 23S ribosomal RNA. These data demonstrate that in RNA's with very different cellular functions, there are domains with similar structural and functional properties and that there is a nucleotide in M1 RNA that affects the site of cleavage by the enzyme. 相似文献
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In 2012 when many sheep flocks in northern‐central Tasmania were experiencing a high prevalence of ovine Johne's disease, 34 wild adult fallow deer shot on or near infected properties were negative to microscopic Mptb lesions of the ileo‐caecal valve, terminal ileum and ileo‐caecal lymph nodes. This study demonstrated 95% confidence of detecting Johne's disease in this fallow deer population if ≥10% of animals were shedding Mycobacterium avium subsp. paratuberculosis in their faeces, or if ≥21% of animals were sub‐clinically infected. 相似文献
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