Effects of Tail Docking on Milk Quality and Cow Cleanliness

Abstract

The objective of this study was to determine the effectoftaildockingonsomaticcellcount(SCC),intra- mammary infection (IMI), and udder and leg cleanli- ness in commercial dairy herds. Lactating dairy cows (n = 1250) from eight Wisconsin farms were blocked by farm and randomly allocated to tail docked (D) or control (C) groups. Milk samples, somatic cell counts, and hygiene scores were collected for 8 to 9 mo. The prevalence of IMI was determined for each of the five occasions when milk samples were obtained. Udder and leg cleanliness were assessed during milk sample collection. Docked andcontrol animalswere compared bylogSCC,prevalenceofIMI,andlegandudderclean- liness score. Variables were analyzed according to all treatment, period, and farm interactions. At the end of the study period 76 (12.2%) and 81 (13%) of cows were culled in the D and C groups, respectively. There were no significant differences in the initial data for parity, daily milk yield, logSCC, or DIM between treatment groups. Effects significant to farms were identified for all variables over all periods. Period was significantforallvariablesexceptfortheprevalenceof environmental pathogens, but no period × treatment interactions were detected. There was no significant difference between treatment groups for somatic cell count. The prevalence of contagious, environmental, or minor pathogens did not differ significantly be- tween treatment groups. This study did not identify any differences in udder or leg hygiene or milk quality that could be attributed to tail docking.