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51.
Cook CJ 《New Zealand veterinary journal》1999,47(2):67-70
AIMS: As kappa(kappa)-opioids have marked effects on pain threshold in sheep during oestrus, late pregnancy and after birth, a study was undertaken to determine if kappa -opioids also had other roles during these states. METHODS: Opioid agonists (GR89696, DAMAGO) were administered into either the lateral hypothalamus (LH) or amygdala of non-pregnant sheep (n = 5) or pregnant sheep (n = 15) in late pregnancy (n = 5) within 12 h of birth (n = 5) or in the third week after birth (n = 5). Cortisol, behavioural and electrocardiographic responses to an auditory stimulus were assessed with and without drug administration, as was feed consumption and suckling events. RESULTS: In non-pregnant sheep, DAMAGO injected into either the LH or amygdala had little effect on the response to the auditory stimulus but when injected into the LH did decrease food consumption. GR 89696 had no obvious effects. In late pregnancy, cortisol and heart rate responses to the auditory stimulus were significantly reduced compared to the non-pregnant animals irrespective of treatment. This was also the case in the third week after birth. Immediately post-partum cortisol responses were closer to that seen in the non-pregnant animal. In late pregnancy and both post-partum periods, GR 89696 in the LH significantly increased feed consumption while DAMAGO had no significant effects. GR 89696 injected into the amygdala reduced the behavioural response to the auditory stimulus in late pregnancy and both post-partum periods. CONCLUSION: Changes in sensitivity to opioids occur in both the amygdala and LH with pregnancy and after birth. These may influence maternal behaviours and feed intake. 相似文献
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W Cook 《The Veterinary record》1973,93(1):15-17
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The anthelmintic efficiency of haloxon in horses 总被引:1,自引:0,他引:1
T F Cook 《New Zealand veterinary journal》1973,21(5):82-84
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A new dipping concept 总被引:1,自引:1,他引:0
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Distribution of immunoglobulin-bearing cells in the gut-associated lymphoid tissues of the turkey: effect of antibiotics 总被引:2,自引:0,他引:2
Distribution of immunoglobulin (Ig)-bearing cells in the gut-associated lymphoid tissues of antibiotic treated and untreated control turkeys (Meleagris gallopavo) was compared. Antibiotic treatment was similar to a regimen used in commercial turkey production, which included preincubation dipping of fertile eggs in gentamicin solution, injection of turkeys with gentamicin at hatching, and inclusion of chlortetracycline in the diet. Tissues were examined from turkeys at 3, 7, 14, and 21 days of age with a direct immunofluorescence procedure. Cell distribution in control turkeys was as follows: In the bursa of Fabricius, IgA-carrying cells predominated at 3 days of age, but at later intervals, the 3 classes of Ig-bearing cells were in equal numbers. In the cecal tonsils, IgM- and IgA-bearing cells were in larger numbers at 3 days of age, whereas, the IgG-bearing cells were sparsely distributed. By 7 days of age, IgM cells became more numerous in the cecal tonsils and remained numerous until 21 days of age. At 3 days of age, IgA cells predominated in the small intestines and IgM cells predominated in the large intestine. At 7 and 14 days of age, IgM cells were more numerous in the small and large intestines, but by 21 days of age, IgA cell population equaled that of IgM. The IgG cells were generally sparse in the intestines. Antibiotic treatment often resulted in lower numbers of Ig-positive cells, especially those bearing IgM and IgA. Normal development of the bursa of Fabricius was also retarded in this group. 相似文献
60.
Jehn CT Perzak DE Cook JL Johnston SA Todhunter RJ Budsberg SC 《Journal of the American Veterinary Medical Association》2003,223(9):1272-1275
OBJECTIVE: To evaluate the quality of information regarding osteoarthritis (OA) in dogs currently available on the World Wide Web. DESIGN: Survey study. PROCEDURE: 5 search engines were searched with the keywords "dog," "degenerative joint disease," "canine," and "osteoarthritis," and the first 50 sites listed by each search engine were analyzed. Unique Web site addresses were distributed to 3 diplomates of the American College of Veterinary Surgeons, who provided a standardized evaluation of each site. RESULTS: 30 unique Web sites were evaluated. Twenty (66%) provided information consistent with conventional knowledge as outlined in textbooks and peer-reviewed literature, 8 (27%) provided experimental or anecdotal information in addition to conventional knowledge, and 2 (7%) provided misleading information. Mean scores for overall usefulness of the information provided in regard to clinical features of and treatment for OA were 1.3 and 1.5, respectively (1 = information of minimal use; 5 = very useful information). Twenty-three (77%) sites encouraged pet owners to seek the advice of a veterinarian. Twenty-three (77%) sites were given overall quality scores < 2, and 7 (23%) were given scores between 2 and 3 (1 = site was counterproductive; 5 = site was very valuable). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the quality of information currently available on the Web that addresses OA in dogs is questionable. Although most of the sites conveyed some conventional information with reasonable accuracy, the information was incomplete, of minimal use, and often considered counterproductive. 相似文献