Abstract #M50

# M50
Evaluating teat skin condition in response to phenoxyethanol as a post-milking teat disinfectant on lactating dairy cows.
S. K. Reeves*1, M. R. Borchers1, J. M. Bewley1, 1Department of Animal and Food Sciences, University of Kentucky, Lexington, KY.

Alternatives to iodine-based teat dips may decrease risk of iodine residues in milk. The objective of this study was to evaluate how a post-milking teat dip containing phenoxyethanol as the active ingredient and a 5% emollient (treatment) affected teat end condition compared with a 1% iodine solution (control). A 9-wk, split-udder, non-inferiority study was conducted on 111 lactating Holstein dairy cows at the University of Kentucky Coldstream Research Dairy. The treatment (left side) and control (right side) were applied using a non-return dip cup. Teats were scored once a week, in accordance with NMC guidelines, for 9 weeks on a 1 (desirable) to 3 (undesirable) scale for teat skin chapping, teat skin dryness, and teat skin color. A 1 (desirable) to 4 (undesirable) scale was used for teat end condition. Data analyses were conducted with SAS Version 9.3 (SAS Institute Inc., Cary, NC). The FREQ procedure generated frequency distributions and the MIXED procedure generated a mixed linear model evaluating the effect of teat, week, and their interaction on teat end condition, teat skin color, teat skin chapping, and teat skin dryness. Teat skin chapping and teat skin color remained at a score of 1 throughout all 9 weeks of the study and were not analyzed further. For teat end condition, no significant differences in scores between treatment teats and control teats. For teat dryness, scores for treatment front teats were significantly greater than control front teats (1.10 ± 0.01 vs. 1.06 ± 0.01; P ≤ 0.001). Temporary increases in dryness scores during study wk 4, 5, 6, and 9 (P ≤ 0.01) on the treatment side occurred during expected teat exfoliation. The scores comparing treatment and control teats are significantly different, but are minimal enough that they do not suggest a biological difference. Results indicate phenoxyethanol may serve as an alternative to iodine-based teat dips, which raise a risk of milk iodine residues.

Key Words: post-dip, teat condition, split udder dairy model