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101.
Further studies are reported on the use of succinylcholine as an immobilizing agent for the deer (Odocoileus). The dosage required for complete immobilization was 0.06 mgms per kilogram body weight (0.027 mgms per pound). This level induced full effects within two to ten minutes of administration (intramuscular) and caused immobilization for periods ranging between eight and thirty minutes. No harmful side effects have been noted on sequential administration of this compound at monthly intervals.  相似文献   
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Currently, the pathogenic role of Ehrlichia canis in cats has been proposed predominantly on the basis of the serologic evidence of natural infection and the infrequent detection of morulae-like structures within the cytoplasm of leukocytes in cats. The purpose of this report was to provide molecular evidence supporting E. canis-like infection in 3 cats that had clinical manifestations consistent with canine ehrlichiosis but lacked antibodies to E. canis antigens. Serum from all 3 cats contained antinuclear antibodies (ANAs). The predominant disease manifestation was polyarthritis in 1 cat and bone marrow hypoplasia or dysplasia. accompanied by pancytopenia or anemia and thrombocytopenia, in 1 cat each. The alignment of E. canis partial 16S ribosomal DNA (rDNA: 382 nucleotide positions), amplified from EDTA blood samples from each cat, was identical to each other and was identical to a canine isolate of E. canis (GenBank accession number AF373613). In 1 cat, concurrent treatment with corticosteroids may have interfered with the therapeutic effectiveness of doxycycline for the elimination of E. canis-like infection. To further define the spectrum of ehrlichiosis in cats, polymerase chain reaction (PCR) testing may be necessary until serologic testing is thoroughly validated in experimentally or naturally infected cats. In addition, until E. canis has been isolated from cats and several tissue culture isolates are available from disparate geographic regions for detailed comparative genetic study, the molecular evidence presented in this study supporting E. canis-like infection in cats must be interpreted with caution.  相似文献   
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Nonlinearity     
Cowan J 《Science (New York, N.Y.)》1982,217(4560):624-625
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The use of barley in choice feeding of the Turkey   总被引:1,自引:1,他引:0  
1. Two‐choice feeding of the male turkey from 50 d of age was investigated using pelleted barley and a turkey starter diet, whole barley and the starter diet, a ground barley‐based turkey finisher diet and the starter diet, pelleted barley and a series of complete diets and compared with feeding the series of complete diets alone.

2. For turkeys on the first four treatments on average 21%, 21%, 42% and 5% by weight, respectively, of food consumed was the barley alternative.

3. There were no significant differences in final body weight between turkeys on choice treatments and those receiving the series of complete diets alone.  相似文献   

108.
The relationship between serum androgen concentrations and relative density changes in the antlers and long bones of male deer was determined. Four male white-tailed deer were sampled 2 times a week during the antler-growing period. Serum androgen values were determined by radioimmunoassay, and relative bone mass (RBM) coefficients were determined by radiograph densitometry. As circulating androgen concentrations increased over the antler-growing period, the RBM coefficients of the antler increased from a mean of 18.5 (+/- 1.96 SD) to a mean of 57.7 (+/- 2.74) at 2 weeks after "rubout." Concurrently, the RBM coefficients of the metacarpus decreased from a mean of 52.0 (+/- 1.92) to a mean of 46.4 (+/- 1.86). There were positive correlation between increasing androgen concentrations and increasing antler RBM and negative correlation between androgens and decreasing metacarpus RBM. Antler RBM coefficients continued to increase after rubout, but metacarpus RBM did not change after rubout. Two castrated deer were injected subcutaneously with 1 g of testosterone and sampled every other day. Similar but smaller changes occurred in RBM values of the metacarpus and developing antler.  相似文献   
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AIMS: To examine the effect of reducing the abundance of brushtail possums (Trichosurus vulpecula) on the distribution and prevalence of bovine tuberculosis (Mycobacterium bovis, Tb) in possums and the incidence of Tb in domestic cattle on a group of farms in the central North Island, New Zealand. METHODS: The cumulative yearly incidence of Tb infection from 12 cattle herds was estimated from annual tuberculin testing and abattoir inspection data over the period 1983-98. Intensive control of possum populations began for six of the herds in 1988, five herds in 1994 and the remaining herd in 1996. The prevalence and distribution of macroscopic M. bovis infection in possums and an index of possum abundance was estimated during yearly cross-sectional surveys from 1988 to 1998. This enabled formal testing of the link between the abundance of tuberculous possums and the incidence of Tb in cattle. RESULTS: Before possum control, infected possums were clustered in foci on or adjacent to the farms with the highest annual incidence of tuberculosis in cattle, and had an overall prevalence of macroscopic M. bovis infection of 2.3%. The prevalence of disease declined to zero with ongoing possum control, although infected possums continued to be found during the first 5 years of control. Maintaining the possum population at an average of 22.1% of its pre-control density significantly reduced the odds of the cumulative yearly incidence of Tb in cattle by 77% during the first 5 years of possum control and a further 65% in the second 5-year period. Nine of 11 tuberculous possums identified since the start of possum control were found within the areas where infected possums were clustered during the pre-control survey, suggesting that the persistence of infection within these clusters rather than infected immigrants was the source of ongoing disease. Annual estimates of the prevalence of tuberculous possums broadly followed the predictions of Barlow's possum-Tb model for a controlled possum population. CONCLUSION: The results support the hypothesis that tuberculous possums transmit bovine tuberculosis to domestic cattle, and therefore that reducing the abundance of tuberculous possums reduces the incidence of Tb in cattle. If the level of possum culling is sufficient, it appears that M. bovis infection may be eradicated from possum populations. Better information on population density, rate of increase and annual culling rates would have been needed for a truly independent examination of the Barlow possum-Tb model.  相似文献   
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