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941.
D S Bradway S Torioni de Echaide D P Knowles S G Hennager T F McElwain 《Journal of veterinary diagnostic investigation》2001,13(1):79-81
The complement fixation (CF) test commonly is used to identify cattle infected with Anaplasma marginale prior to interstate or international movement. Estimates of the accuracy of the CF test in detecting animals persistently infected with A. marginale vary widely. In this study, the sensitivity and specificity of the CF test for detection of carrier animals was determined using serum from 232 cattle previously defined as A. marginale positive or negative by nested polymerase chain reaction methods and hybridization. Considering results from 2 independent laboratories and interpreting a 1:5 suspect reaction as positive, the best estimate of CF test sensitivity was 20%, with a specificity of 98%. Using a 1:10 cutoff, sensitivity decreased to 14% and specificity increased to 99%. Results of this study indicate that the CF test is ineffective for identifying cattle persistently infected with A. marginale and thus is inadequate for anaplasmosis regulatory and surveillance programs. 相似文献
942.
D T de Waal 《The British veterinary journal》1992,148(1):6-14
This review focuses on equine piroplasmosis with specific reference to its distribution, diagnosis and clinical and pathological signs. The more common used drugs are discussed both with reference to treatment and chemosterilization. Areas requiring further research are also briefly mentioned. 相似文献
943.
During vaginal fluid examinations (Papanicolaou) to study the physiological sexual cycle of Cebus sp., abundant Dipetalonema gracile microfilariae (110-160 microns x 4-5 microns, without a sheath) were encountered in the genital fluid, but not in peripheral blood. Considering the great difficulty in diagnosing this obscure parasitosis, exfoliative colpocytology was found to be an efficient diagnostic. 相似文献
944.
Lelystad virus, the cause of porcine epidemic abortion and respiratory syndrome: a review of mystery swine disease research at Lelystad. 总被引:10,自引:0,他引:10
G Wensvoort E P de Kluyver J M Pol F Wagenaar R J Moormann M M Hulst R Bloemraad A den Besten T Zetstra C Terpstra 《Veterinary microbiology》1992,33(1-4):185-193
This paper reviews the laboratory investigations that led us to isolate the Lelystad virus and demonstrate that this virus causes mystery swine disease. We describe: 1) isolating the virus from the disease; 2) characterizing the virus as a new enveloped RNA virus; 3) reproducing the disease experimentally with the isolated Lelystad virus; 4) isolating the virus from the experimentally induced disease. 相似文献
945.
G López de Torre J J Candotti A Reverter M M Bellido P Vasco L J García J S Brinks 《Journal of animal science》1992,70(9):2668-2672
Weight-age data from 50 Retinta beef cows from 8 to 97 mo of age located in southwestern Spain were fitted to von Bertalanffy, Brody, and Richards functions to determine the relationship between growth curve parameters and cow efficiency. Only cows having at least 31 weights were included in the analysis. Von Bertalanffy, Brody, and Richards functions were fitted to weights of each cow. Relevant parameters of the three functions are A and K, associated with the asymptotic mature weight and rate of maturing, respectively. Criteria for comparisons among the three functions were computing difficulty, goodness of fit, and lack of bias of A. Productivity indicators were number of calves weaned during the first five calving seasons (NC), average birth weight (BWT), average weaning weight (WW), and average weaning weight per cow per year (WWY). The von Bertalanffy function was selected as the most appropriate. Least squares means for A and K were 650 +/- 8.17 kg and .038 +/- .001 mo-1, respectively. The values of NC, BWT, WW, and WWY were 4.0 +/- .11 calves, 38.2 +/- .4 kg, 218 +/- 5 kg, and 172 +/- 5 kg, respectively. Regression analysis for A indicated a decrease in NC when mature weight increased (P less than .05). There was a nonsignificant trend for heavier cows (higher A) to have calves with heavier BWT or WW. The value of WWY increased (P less than .05) with increased maturing rate (K) of cows. No significant associations were found between K and BWT or WW.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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949.
Post-mortem examination of 658 goats showed that 17 (2.5%) exhibited hepatic abscesses. The following bacteria were isolated: Corynebacterium pseudotuberculosis (58.9%), Escherichia coli (11.8%), Corynebacterium sp. (11.8%), Pasteurella haemolytica (5.9%), Proteus sp. (5.9%) and Staphylococcus aureus (5.9%). Hepatic abscesses occurred more frequently in adult animals. Eleven of the 17 goats (64.7%) were older than 12 months of age. Four goats (23.5%) were 12 months of age and only two (11.8%) were less than 1 year of age. All of the goats with hepatic abscesses were in poor nutritional condition and the abscesses were invariably associated with accompanying pathological disorders at other body sites. 相似文献
950.
Ilex crenata Thunb. cultivar ‘Green Luster’ and Juniperus horizontalis Moench. cultivar ‘Plumosa’ were grown in 3 container-media for 13 months. The container-media were dissected by 2 horizontal cuts to yield 3 depth zones, 3 equal concentric areas were outlined on the lower surface of each depth zone and root distribution determined. A greater number of Ilex roots were in the 2 inside concentric areas of the bottom two-thirds of the peat:perlite medium than in the same divisions of soil:peat:sand and pine bark:sand media. Juniperus roots were more evenly distributed through the depth zones of pine bark: sand than soil:peat:sand or peat:perlite media. 相似文献