Dry-off and dairy cow udder health and welfare: Effects of different milk cessation methods

M.J. Vilar,P.J. Rajala-Schultz

doi:10.1016/j.tvjl.2020.105503

Abstract

The cessation of milking at the end of lactation is a routine management practice in dairy herds, and the importance of the dry period for milk production and udder health, has long been recognized. Among countries and herds, drying-off practices differ and include various milk cessation methods, such as changes in milking frequency and in feeding, the use of antibiotic dry cow therapy and teat sealants, and changes in housing. Published studies reporting methods of stopping milk production are scarce, and there are no uniform recommendations on optimal procedures to dry cows off for good udder health, cow welfare, and milk production. This review describes methods to stop mik production to prepare cows for the dry period and their effects on mammary involution, udder health, and dairy cow welfare. Milk yield at dry-off (the final milking at the end of lactation) is important for rapid involution, which stimulates the immune system and promotes good udder health and cow welfare. Based on the findings of this review, gradual cessation of milking over several days before the final milking can effectively reduce milk yield at dry-off and accelerate mammary gland involution while maximizing cow comfort and welfare. Data from this review indicate a target production level of 15 kg/day of milk or less at dry-off.

Highlights

In recent decades, dairy production in developed countries has gone through considerable structural changes, with the number of farms declining and herd sizes increasing
Different methods to stop the cow's milk production to prepare her for the dry period include abrupt or gradual cessation of milking, changes in feeding, and the use of pharmaceutical products
The time immediately after dry-off is a high-risk period for new intramammary infections (IMI); milk still accumulates in the udder, the keratin plug has not yet completely formed, and the natural protective factors in the mammary gland are still low

Summary

Introduction

Dairy production in developed countries has gone through considerable structural changes, with the number of farms declining and herd sizes increasing. Drying-off practices include various milk cessation methods (reduced frequency of milking and changes in feeding), administration of DCT and internal teat sealants, and housing changes. The methods used are either abrupt or gradual dry-off In the former, all dryingoff practices occur in 1 day, whereas in the latter, they may extend from a few days to several weeks prior to the final milking. DRY, Drying-off; DO, dry-off; DP, dry period; CALV, after calving; SCC, somatic cell counts; IMI, intramammary infections; PMN, polymorphonuclear leukocyte; BSA, bovine serum albumin; NEFA, non-esterified fatty acids; BCS, body condition score; DCT, antibiotic dry cow therapy; ITS, internal teat sealant; DIM, days in milk. ‘milk cessation methods’ in this review refer to those practices deployed to stop the cow's milk production, including changes in frequency of milking or changes in feeding, or the administration of pharmaceutical products. The aim is to describe reported methods and summarize the effects of these methods on milk yield at dryoff, on mammary involution, on udder health, and on cow welfare

Literature search

Findings

Conclusions