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Of 48 lambs slaughtered at a local abattoir, 60.4% were either found to be infected with Taenia hydatigena cycts, or showed evidence of abortive infections (white spots on the liver) with that parasite. The micro ELISA test and the IHA test did not distinguish between animals showing evidence of infection at slaughter and those which did not. Both tests gave results which correlated significantly with each other. The antigens used in the tests cross-reacted with each other, which may be the reason for the large number of false negative results. 相似文献
63.
The combination of a defined medium with single-pass perfusion has made possible long-term maintenance of beating rat hearts at 22 degrees C in vitro. The 6- to 9-day survival period appears to be the longest so far reported for hearts. This method provides a stable system which should be useful for investigating the role of single factors in myocardial preservation and evaluating the effects of exposure to pharmacological and toxicological agents. 相似文献
64.
P. Boulanger G. L. Bannister A. S. Greig D. P. Gray G. M. Ruckerbauer N. G. Willis 《Canadian journal of veterinary research》1967,31(1):16-23
African swine fever immunofluorescent conjugates were prepared in swine and used successfully in the demonstration of viral antigen in frozen tissue sections and in inoculated tissue culture cells. Cross reactivity was observed with the six strains used in the inoculation of swine. The high antibody content of the serum of immune swine did not interfere with demonstration of the antigen in frozen tissue sections of certain of their organs. The localisation and extent of antigen varied with the stage of infection. The virus was demonstrated in spleen and other organs as early as after one day of pyrexia and until after death of the animal. A pool of hog cholera and African swine fever conjugates stained with dyes of different colours was used in the localisation of respective antigens in experimental mixed infection. 相似文献
65.
Willis AM Anderson DE Gemensky AJ Wilkie DA Silveira F 《American journal of veterinary research》2000,61(12):1542-1544
OBJECTIVE: To estimate intraocular pressure (IOP) in eyes of healthy camelids, using applanation tonometry. ANIMALS: The eyes of 34 camelids (16 llamas [Lama glamal and 18 alpacas [L. pacos]) that did not have major abnormalities of the ocular surface or intraocular abnormalities. PROCEDURE: Tonometry measurements were obtained from each eye 3 times during a 24-hour period. Each measurement was the mean of several corneal applanations obtained by use of an applanation tonometer. Data were analyzed, using an ANOVA for a repeated-measures design. RESULTS: Mean (+/- SEM) IOP of llamas and alpacas was 13.10+/-0.35 and 14.85+/-0.45 mm Hg, respectively. Range of IOP was 7 to 18 mm Hg for llamas and 11 to 21 mm Hg for alpacas. Mean IOP of llamas was significantly less than the mean IOP of alpacas. Significant differences in IOP were not detected between the right and left eye of animals. Significant differences in IOP were not attributed to sex, age, or time of measurement within llamas or alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Establishing the mean and range of IOP of clinically normal llamas and alpacas provides a frame of reference that is important for use in a complete ophthalmic examination of camelids, which can assist clinicians in the diagnosis of glaucoma and uveitis. Reasons for the difference in mean IOP between llamas and alpacas are unknown. Although the difference may be unimportant clinically, this finding reiterates the fact that caution must be used when extrapolating IOP among species. 相似文献
66.
Ridyard AE Corcoran BM Tasker S Willis R Welsh EM Demetriou JL Griffiths LG 《The Journal of small animal practice》2000,41(12):558-561
Four cases of spontaneous laryngeal paralysis in juvenile white-coated German shepherd dogs are described. The presenting signs were typical for laryngeal paralysis, with stridor present in all four cases. Laryngoscopy revealed bilateral laryngeal paralysis in three cases, and unilateral paralysis in one. Concurrent megaoesophagus was also identified in one dog. All dogs underwent surgical treatment for laryngeal paralysis. Euthanasia was performed in one case due to intractable regurgitation and aspiration pneumonia. A possible association with white coat colour is discussed. 相似文献
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测定了利木赞×娟姗牛杂交一代3头公牛所有回交后代的背最长肌和半腱肌的剪切力、pH值及煮 制损失3个表型性状,与已构建的遗传连锁图谱和基因型值相结合,利用QTL Express软件的“Half-Sib QTL Analysis Servlet”进行QTL分析。共发现6个可能的QTL位点,其中背最长肌剪切力性状3个QTL(BTA2 45 cM,BTA29 54 cM)、半腱肌剪切力1个QTL(BTA2 12 cM)、半腱肌pH值1个QTL(BTA24 0 cM)、背最长肌 煮制损失1个QTL(BTA142 cM)。 相似文献
69.
JK Harmon SJ Ostro LAM Benner KD Rosema RF Jurgens R Winkler DK Yeomans D Choate R Cormier JD Giorgini DL Mitchell PW Chodas R Rose D Kelley MA Slade ML Thomas 《Science (New York, N.Y.)》1997,278(5345):1921-1924
Radar observations of comet Hyakutake (C/1996 B2) made at the Goldstone Deep Space Communications Complex in California have detected echoes from the nucleus and from large grains in the inner coma. The nucleus of this bright comet was estimated to be only 2 to 3 kilometers in diameter. Models of the coma echo indicate backscatter from porous, centimeter-size grains ejected anisotropically at velocities of tens of meters per second. The radar observations suggest that a comet's activity may be a poor indicator of its size and provide evidence that large grains constitute an important component of the mass loss from a typical active comet. 相似文献
70.