dry off

Drying off is the deliberate cessation of milking a dairy cow in the weeks before she calves. A cow typically stops producing milk naturally once lactation ends, but farmers initiate this process on schedule, usually around 6 to 8 weeks before the expected calving date, to allow her udder tissue to recover and prepare for the next lactation cycle.

The timing and method matter. Abrupt stopping causes udder congestion and pain; instead, most producers reduce milking frequency gradually, moving from twice daily to once daily milking for several days before complete cessation. This gentler transition minimizes inflammation and reduces the risk of mastitis during the vulnerable dry period. Some herds use a technique called selective drying, where only higher-producing cows are dried off while lower producers continue on extended lactation.

During the dry period, the cow requires different nutrition than a milking animal. She needs lower energy but adequate minerals, particularly calcium and magnesium, to prevent metabolic disorders around calving. Facilities must protect her from injury and contamination, since the teat canal closes but is not impervious. Many farms apply intramammary antibiotics at drying off to prevent infection during this non-lactating phase when the udder is biochemically defenseless.

The dry period is not idle time. The cow's body redirects energy to fetal growth and preparation of the udder for the next lactation. Cows that are not dried off properly may enter calving exhausted, produce less colostrum, or suffer from retained placenta and other periparturient complications. The dry period also breaks the reproductive cycle, allowing the cow's body to reset metabolically.

Economic pressure sometimes shortens dry periods below 6 weeks or extends milking into late pregnancy. This reduces total lactation days per year but can compromise udder health and calf vigor. The term "dry off" derives simply from the state of the udder becoming dry as milk production ceases and is retained in the mammary tissue rather than being removed.