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Migration of leukocytes into the mammary gland is an essential element of resistance to infection which is likely influenced by expression of adhesion molecules. The contribution of subsets to mammary gland resistance remains unclear. Mononuclear cells from milk and blood of dairy cows were examined for variation in CD4+, CD8+, and WC1+ (Workshop Cluster 1; marker for gammadelta T cells) lymphocyte phenotypes and expression of LFA-1 and L-selectin at several time points during the periparturient period and at Week 16 of lactation. Proportions of CD4+ T cells were higher (p < or = 10.05) in blood than milk at all times between Week 0 and Week 16 relative to calving; the inverse was true of CD8+ cells. Expression of L-selectin was lower (p < or = 0.05) on CD4+ cells and higher on CD8+ cells from milk. The WC1+ subset was more frequent in blood than in milk except at calving when the opposite was true. After calving, proportions of L-selectin+ WC1+ cells decreased steadily to Week 16. Expression of LFA-1 was examined on mononuclear cell populations and found to be lower on milk cells and did not vary over time. We conclude that proportions of T cells subsets differ significantly between blood and milk, particularly around calving. Corresponding variations in L-selectin expression may indicate a role for this molecule in regulating the movement of CD8+ and WC1+ T cells into the bovine mammary gland. 相似文献
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Physiological responses of poultry to ambient temperature 总被引：1，自引：0，他引：1
M van Kampen 《Archiv fuer experimentelle veterinaermedizin》1984,38(3):384-391
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Kampen AH Olsen I Tollersrud T Storset AK Lund A 《Veterinary immunology and immunopathology》2006,113(1-2):53-63
Fifteen clinically healthy calves were sampled every week during the first 5 weeks of life and thereafter every month until the age of 6 months. The percentages and absolute values of CD4+, CD8+ gammadelta TCR+ and WC1+ T cells, CD21+ B cells and NKp46+ NK cells were determined by flow cytometry, and the expression of the interleukin-2 receptor alpha chain (CD25) was measured to assess the level of activation of the lymphocyte subpopulations. Neutrophil phagocytosis, respiratory burst and bactericidal activity were measured in five different neutrophil function assays. Most of the parameters examined reached a stable level during the first 6 months of life. The proportions of CD4+ and CD8+ lymphocytes remained relatively stable during the study period, while there was a moderate decrease in the relative percentage of gammadelta T cells from birth to approximately 5 months of age. However, the absolute numbers of gammadelta T cells per millilitre of blood remained stable throughout the study period and did not display significant variation with age. The percentage of cells expressing the B-cell maturation marker CD21 increased significantly over the first 5 months of life. The proportion of NK cells showed substantial variation during the study. Marked differences in the relative proportions of the lymphocyte subpopulations were noted between the individual calves, and the individual ranking of the animals was largely maintained over time. CD25 expression was detected on a mean of 6.6% of the CD4+ cells, while a lower percentage of the other lymphocyte subpopulations expressed this receptor. Phagocytic activity was demonstrated in approximately 90% of the neutrophils, and this proportion remained stable during the entire study period, while respiratory burst activity showed a moderate decrease during the first 2 months of life. The present study shows that the T-cell subpopulations are present in peripheral blood of calves at levels comparable with adult values, while the B-cell population increases significantly with age. The decrease in the relative percentage of gammadelta T cells appears to be attributable to an increase in the absolute numbers of CD4+ and CD21+ cells, rather than a change in absolute gammadelta T-cell numbers. Furthermore, the results indicate that the neutrophilic granulocytes are functional and able to mount an effective response in young calves from the first week of life. 相似文献
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Charles D. Vail DVM Arthur J. Nestved DVM J. Brent Rollins DVM Gerald K. Huff DVM Thomas B. Hartgrove DVM Dan R. Evans DVM John J. Clapper DMV Kent R. Van Kampen DVM PhD Bruce A. Peters PhD Charles A. Hay PhD 《Journal of Equine Veterinary Science》1990,10(6):399-403
The effect of using Propionibacterium acnes, (EqStim®)a as an adjunct to conventional therapy in the treatment horses with Equine Respiratory Disease Complex (ERDC) was evaluated. Of the 45 horses entering the study, 25 received EqStim® and conventional therapy while 20 horses (negative controls) received a carrier solution of 12.5% ethanol-saline and conventional therapy. At the end of the 14 day test period, 96% (24/25) of the horses treated with EqStim® and conventional therapy showed clinical improvement or complete recovery as compared to the control group in which 35% (7/20) of the horses (treated with conventional therapy and carrier) showed clinical improvement or complete recovery. 相似文献
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Effects of locoweed intoxication on the genital tract of the ram 总被引：1，自引：0，他引：1
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