Effect of Incomplete Milking on the Incidence of Udder Irritation and Subsequent Milk Yield of Dairy Cows

Abstract

Summary Incomplete milking of dairy cows was practiced for ten-day periods to determine its effect on udder irritation and subsequent milk yield. Two or four pounds of milk were left in the udders at each milking. One group of cows was free from all mastitis infections, whereas most of the cows in the second group had persistent mastitis infections other than Streptococcus agalactiae . Each ten-day incomplete milking period was preceded and followed by a seven-day normal milking period. Leaving 4lb of milk in the udder at each milking resulted in a greater permanent reduction in milk yield than did leaving 2lb in the udder. The leucocyte counts, Whiteside ratings, and CMT ratings did not increase during the periods of incomplete milking. The cows with persistent mastitis infections showed higher values for all three indicators of udder irritation than cows free from infections.