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161.
Lockyer JN 《Science (New York, N.Y.)》1886,7(169):386-387
162.
163.
The vulvar labia of ewes naturally infected with ureaplasma were significantly more swollen and red than those of uninfected ewes. Similar changes were observed following experimental infection of previously uninfected ewes. These differences, although statistically significant, were not sufficiently marked to be useful in diagnosing infection by clinical examination. 相似文献
164.
The 1998 Report of the American Association of Feline Practitioners and Academy of Feline Medicine Advisory Panel on Feline Vaccines was developed to help veterinary practitioners formulate vaccination protocols for cats. The current panel report updates information, addresses questions, and speaks to concerns raised by the 1998 report. In addition it reviews vaccine licensing, labeling, and liability issues and suggests ways to successfully incorporate vaccination protocol changes into a private practice setting. 相似文献
165.
A.J.A. Vinten D.R. Lewis D.R. Fenlon K.A. Leach R. Howard I. Svoboda I. Ogden 《Soil Use and Management》2002,18(3):223-231
Abstract. Slurry from farm animals may contaminate water supplies, rivers and bathing waters with faecal coliforms, such as Escherichia coli . Where animals harbour the O157 strain the hazard to human health is particularly high, but both the hazard level, and the low incidence and sporadic nature of the excretion of E. coli O157 make it difficult to study this strain under field conditions. The survival of total E. coli and of E. coli O157 were compared in the laboratory for two soils under controlled temperature and moisture. E. coli O157 die-off rate was the same as or quicker than for total E. coli . This result meant that field experiments studying the fate of total E. coli should give a satisfactory evaluation of the risk of water contamination by the O157 strain. In four field experiments at three sites, slurry containing total E. coli numbers of 2.2 × 104 to 5.7 × 105 colony forming units per mL (c.f.u. mL–1 ) was applied to drained field plots. Field die-off was faster than expected from laboratory experiments, especially in one experiment where two weeks dry weather followed application. In all but this experiment, the first drain flow events after slurry application led to very high E. coli concentrations in the drains (103 to 104 c.f.u. mL–1 ). E. coli O157 was present in the slurry used for two of the experiments (33 c.f.u. per 100 mL in each case). However the proportion of E.coli O157 was very low (about 1 in 105 ) and it was not detected in the drainage water. After the first week E. coli drainage water numbers decreased rapidly but they were 1–10 c.f.u. mL–1 for much of the sampling period after slurry application (1–3 months). 相似文献
166.
S. A. Selim K. M. S. Aziz A. J. Sarker H. Rahman 《Veterinary research communications》1991,15(4):327-333
Faecal samples from 434 calves under 1 year of age (307 diarrhoeal and 127 normal) were collected from three dairy farms and one village in selected areas of Bangladesh. The samples were tested by an enzyme-linked immunosorbent assay (ELISA) to detect the presence of rotavirus antigen. Of 402 dairy calves tested, 28 (7.0%) were positive, of which 21 (7.2%) were from diarrhoeic calves and 7 (6.3%) from non-diarrhoeic calves. Rotavirus infection varied from farm to farm (2.7–9.2%) and there was no positive response from any of the 32 village calves. Rotavirus was most commonly found in calves of 1 week of age or less (up to 22.2% in one group) but was not found in any calves later than 6 months of age. More than 80% of rotavirus-positive samples from diarrhoeic calves exhibited a titre of 128 or more (geometric mean 345±4.5), whereas non-diarrhoeal calves had titres less than or equal to 128 (geometric mean=29±1.9), suggesting that rotavirus infection in calves in Bangladesh was mostly associated with diarrhoea. 相似文献
167.
168.
Bayesian analysis via Gibbs sampling, restricted maximum likelihood (REML), and Method R were used to estimate variance components for several models of simulated data. Four simulated data sets that included direct genetic effects and different combinations of maternal, permanent environmental, and dominance effects were used. Parents were selected randomly, on phenotype across or within contemporary groups, or on BLUP of genetic value. Estimates by Bayesian analysis and REML were always empirically unbiased in large data sets. Estimates by Method R were biased only with phenotypic selection across contemporary groups; estimates of the additive variance were biased upward, and all the other estimates were biased downward. No empirical bias was observed for Method R under selection within contemporary groups or in data without contemporary group effects. The bias of Method R estimates in small data sets was evaluated using a simple direct additive model. Method R gave biased estimates in small data sets in all types of selection except BLUP. In populations where the selection is based on BLUP of genetic value or where phenotypic selection is practiced mostly within contemporary groups, estimates by Method R are likely to be unbiased. In this case, Method R is an alternative to single-trait REML and Bayesian analysis for analyses of large data sets when the other methods are too expensive to apply. 相似文献
169.
A framework is described for partitioning the matrix of between-sample distances that forms a starting point for many ecological studies into contributions attributable to different factors in a structured data set. This partitioning enables a series of ordinations to be produced that better enable an insight to be gained into the effects of the factors. More detailed application of the same partitioning provides a decomposition of each factorial effect into single degree-of-freedom contrasts, which enables reasons for observed trends to be investigated. The methods are illustrated by application to data from a study of marine community structure. 相似文献
170.
M E Kehrli K A Weigel A E Freeman J R Thurston D H Kelley 《Veterinary immunology and immunopathology》1991,27(4):303-319
Blood neutrophil functions, lymphocyte blastogenic responses, serum complement, and serum conglutinin activity of 98 lactating Holstein cows from two genetic lines were evaluated. The genetic lines were produced in a selection experiment that created and perpetuated genetic differences in milk production for up to seven generations. No significant differences between the two genetic lines of cows were found for neutrophil function, lymphocyte blastogenic responses, serum complement levels, or serum conglutinin levels. Significant differences between sire progeny groups within lines were found for unstimulated and mitogen-stimulated lymphocyte blastogenesis (P less than 0.0001), and almost all neutrophil functions (antibody independent neutrophil cytotoxicity, antibody dependent neutrophil cytotoxicity, ingestion of bacteria, iodination, chemiluminescence, chemokinesis, and chemotaxis (P less than or equal to 0.05)). Sire progeny group differences (P less than or equal to 0.0001) within lines for serum complement and conglutinin activity were also found. Neutrophil chemiluminescence activity (positive relationship; P less than or equal to 0.001), concanavalin A-stimulated lymphocyte blastogenesis (positive relationship; P less than or equal to 0.004), and serum conglutinin activity levels (negative relationship; P less than or equal to 0.01) each had small but significant associations with the total milk somatic cell count. Cows seropositive for bovine leukosis virus had increased resting and mitogen-stimulated lymphocyte blastogenic activity and were associated with increased in vitro neutrophil random migration and production of superoxide anion. Estimates of genetic parameters of various immune cell functions, of serum complement and of conglutinin levels for daughters of 11 sires with 4-6 daughters in the data set were determined. In this report, genetic variation was demonstrated for nonspecific humoral and cellular immunity. 相似文献