|Odriscoll, K - NUI DUBLIN, IRELAND|
|Schutz, M - PURDUE UNIVERSITY|
Submitted to: Journal of Dairy Science
Publication Type: Abstract Only
Publication Acceptance Date: March 27, 2008
Publication Date: July 7, 2008
Citation: Odriscoll, K., Schutz, M.M., Eicher, S.D. 2008. Effect of rubber flooring on leukocyte activation during the peripartuient period [abstract]. Journal of Dairy Science. 91, E-Suppl. 1:195. Technical Abstract: This study aimed to evaluate the effect of 2 dairy cow housing systems on innate immune status during the peri-parturient period. Leukocyte counts, phagocytic ability and neutrophil and monocyte differentiation were examined. Cows were assigned to free-stall housing with either rubber (RUB; n=13) or concrete (CON; n=14) at the feed-face immediately after their first calving, and managed on this system during all subsequent lactations. Between lactations cows remained in a straw bedded-pack dry cow pen. A year-round calving system was utilized. Cows entered the experiment at the end of either their 1st (n=16) or 2nd (n=11) lactations. Blood samples were obtained approximately -60, -30, 0, +7 and +14 d relative to calving. Differential leukocyte counts were obtained using an automated cell counter. Phagocytic activity, and cells positive for CD14 and CD18 expression were measured by flow cytometry using labelled micro-beads and antibodies. Treatment effects were determined using repeated measures ANOVA. An interaction of treatment and d (P<0.05) on neutrophil and lymphocyte counts (P<0.05) was found. RUB cows had higher neutrophil and lower lymphocyte numbers post-calving than CON. Neutrophil to lymphocyte ratio tended (P=0.1) to be higher for RUB than CON cows post-calving. There was no effect of treatment on phagocytosis or percentage of cells positive for CD14 or CD18 However, d tended (P=0.1) to have an effect on phagocytic events, with the highest value at day (d) -60. Cells positive for CD14 were greatest on d 0 (P<0.05), and a treatment by d effect was found for cells positive for CD14. CD14 percentages were greater for RUB than CON cows post-calving. A high neutrophil to lymphoctye ratio is associated with physiological stress, but suppressed leukocyte function is associated with peri-partuient period. Thus, the ability of RUB cows to activate neutrophils and monocytes is indicative of an improved immune response. These data are useful for producers to determine the potential benefits of investing in rubber flooring.