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101.
102.
Natural scrapie: detection of fibrils in extracts from the central nervous system of sheep 总被引:1,自引:0,他引:1
Extracts from the cervical spinal cord and from the medulla, thalamus, cerebellum and cerebral cortex of the brains of 10 sheep, histopathologically confirmed as cases of scrapie, were examined by electron microscopy for the presence of scrapie-associated fibrils. Characteristic fibrils were observed in all the extracts except for that from the thalamus of one sheep. No fibrils were found in any extracts from three control sheep. A comparison of these results with a similar study of 22 cases of bovine spongiform encephalopathy (BSE) suggests that in cases of scrapie the area of the brain chosen for the detection of fibrils is less critical than in cases of BSE, in which fibrils are more readily extracted from areas of the brain stem. 相似文献
103.
Methods for early termination of pregnancy in the cow 总被引:1,自引:0,他引:1
F L Dawson 《The Veterinary record》1974,94(23):542-548
104.
Bovine farmers' lung: a clinical syndrome in a herd of cattle 总被引:2,自引:0,他引:2
105.
Seventy-three samples of serum, from 69 horses and one zebra, were subjected to the Rose Bengal Plate, serum tube agglutination, complement fixation, and anti-equine globulin (Coombs') tests for brucellosis. Fifty-one of the samples, from 48 horses, were submitted by practising veterinary surgeons; of these, 22 samples were associated with clinical conditions which might have been due to brucellosis. Fourteen samples were from healthy horses known to have been in contact with infected cattle, and six were from horses which were known not to have been exposed to brucellosis. More reactions at accepted diagnostic levels were obtained to the anti-globulin and complement fixation tests than to the agglutination test. Two horses showed no reactions, other than inconclusive titres to the antiglobulin test, and these titres could have resulted from exposure to Brucella. Eight of nine positive Rose Bengal tests were confirmed by a reaction at diagnostic level in at least one of the other tests, but two sera showing a reaction at diagnostic level to the other tests gave a negative Rose Bengal result. 相似文献
106.
107.
Ovine IgG, IgM and IgA and antisera specific for these immunoglobulins were prepared. The specific antisera were used to estimate the immunoglobulin concentrations in certain sheep body fluids. IgA was shown to be the major immunoglobulin in saliva, lung and lachrymal fluid, tracheobronchial and nasal secretions while IgG was the predominant immunoglobulin in colostrum, milk, bile and serum. 相似文献
108.
Serial changes in the concentrations of IgM, IgG and IgA were compared in specific pathogen free (SPF) lambs which had been vaccinated with live or inactivated parainfluenza 3 virus (PI 3) by either intramuscular (IM) or intranasal (IN) routes followed by aerosol challenge with PI 3. In the serum, an increase in IgM was associated with the primary antibody response to the aerosol challenge, whereas increased IgG was associated with the secondary antibody response. No changes in immunoglobulin concentrations were observed in the nasal secretions of lambs administered live or inactivated virus IM or IN without adjuvant. Marked increases in IgG were found in the serum and nasal secretions of lambs vaccinated IM with inactivated virus in Freund's complete adjuvant (FCA) and fractionation by gel filtration confirmed that the antibody was associated with IgG in both these fluids. 相似文献
109.
Night temperatures warmer than those normally used in commercial production systems promoted vegetative growth in Tagetes patula and Matthiola incana seedlings. In the short (8 h) daylength regime employed, and with a day temperature of 16°C, cool nights (8°C) had a detrimental effect, especially when imposed for 6 weeks from pricking-out rather than later. Night temperatures between 8°C and 16°C did not substitute for the long-day requirement for flowering in Matthiola after 11 weeks' growth, and there was no advantage with respect to vegetative growth in maintaining night temperatures above 12°C. Warmer nights from pricking-out promoted flowering in Tagetes but if applied later (during weeks 7–11) the positive effects were largely on vegetative growth. The implications of these findings for commercial horticulture are discussed. 相似文献
110.
Dawson WW Jeffery G Dawson JC Kessler MJ Rodriguez J Westergaard GC 《Veterinary ophthalmology》2004,7(6):391-396
There is growing evidence for an interaction among fundus pigmentation, character, geography and the function and structure of the outer retina. We examined three inbred groups of rhesus macaques (132 eyes) including all ages. One was a smaller (18 eyes) group. Coat colors were variations of brown-tan however, the smaller group had lighter 'golden' coats and colors. Fundus images were classified for pigmentation and its geographic distribution. In golden-coated animals there was bias toward nasal fundus hypopigmentation with the optic disk as a watershed demarcation zone, which extended in the superior-inferior direction. Temporal fundus hypopigmentation did not occur in the absence of nasal hypopigmentation. More common, darker coated samples showed a characteristic diffuse fundus pigmentation. There was no evidence for albinism or large variations in macular pigmentation. Rhesus monkeys can exhibit geographically controlled genetic development of fundus pigmentation. Hypopigmentation provides for access to the choroidal infrastructure. 相似文献