|O'Driscoll, K - NUI DUBLIN, IRELAND|
|Schutz, M - PURDUE UNIVERSITY|
|Lossie, A - PURDUE UNIVERSITY|
Submitted to: Journal of Dairy Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 26, 2009
Publication Date: September 1, 2009
Citation: O'Driscoll, K., Schutz, M.M., Eicher, S.D., Lossie, A.C. 2009. The effect of floor surface on dairy cow immune function and locomotion score. Journal of Dairy Science. 92:4249-4261. Interpretive Summary: This study evaluated the effect of rubber or concrete floors on cow body movement while walking (locomotion) and white blood cell functions and gene expression over the 30 days prior to and after calving. After calving, cows from the concrete flooring were slower than those from the rubber flooring. Cows in their second lactation were slower than those in their first lactation, and this was more predominant in the cows on the rubber flooring. Cows from the rubber flooring had more of two types of white blood cells after calving (perhaps showing less suppression). After calving, more cells of the cows from the rubber flooring had the receptor for gram negative bacteria (such as some pathogens for cattle and humans, Salmonella or E. coli). This suggests that the cells of the cows on rubber flooring may be more responsive to the environment. However, cows from rubber flooring had greater expression of a gene related to wound healing and the gene associated with pain signals. The ability of the cows from the rubber flooring to activate white blood cells may be indicative of an improved immune response. The roles of the gene for tissue repair and that of the one involved in pain signaling are both still being unraveled for all species. These data show that both of those genes may be important in determining the ability of cattle to respond to environmental stressors. These data are useful for scientists to further elucidate the role of these genes and eventually for producers to determine the potential benefits of investing in rubber flooring that may extend beyond the reduction of incidence of lameness.
Technical Abstract: The study evaluated the effect of 2 dairy cow housing systems on cow locomotion, leukocyte activity and expression of genes associated with lameness, during the dry and peri-parturient period. Cows were assigned to free-stall housing with either rubber (RUB; n=13) or concrete (CON; n=14) at the feed-bunk side of their housing 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. Cows entered the experiment at the end of either their 1st (n=16) or 2nd (n=11) lactations. Locomotion scores and blood samples were obtained at approximately -60, -30, 0, +7 and +14 days relative to calving. Differential leukocyte counts, leukocyte phagocytic activity, cells positive for CD14 (part of the LPS receptor) and CD18 (adhesion molecule) cell surface expression, and gene expression of TAC1 (receptor for substance–P), HRH1 (histamine receptor), and MMP13 (metalloproteinase-13) in blood leukocytes were estimated. Treatment effects on all measures were analyzed using repeated measures ANOVA. Contrary to expectation, provision of rubber flooring did not improve dairy cow locomotion (P>0.05). However day had an effect on locomotion score and speed (P<0.01and P<0.001), both peaking on day 0. Post calving, cows on CON were slower than RUB, relative to pre calving (P=0.01). Cows at the end of the 2nd lactation were slower than cows at the end of the 1st (P<0.01), particularly RUB cows (P<0.01). 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 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. RUB cows had higher expression of MMP13 than CON (P<0.05), which is more highly expressed in lame cows than sound. Cows in RUB also tended to have higher expression levels of TAC1 (P=0.06), the receptor for substance-P. 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 may be indicative of an improved immune response. The roles of MMP-13 in tissue repair and TAC-1 as a response to pain signals are both still being unraveled for all species. These data show that MMP-13 and TAC-1 may both be important in determining the ability of cattle to respond to environmental stressors. These data are useful for producers to determine the potential benefits of investing in rubber flooring that may extend beyond the reduction of incidence of lameness.