The Effect of Prepartum Milking upon the Quantity of Milk Produced during the Subsequent Lactation

There is a lack of agreement among research workers as to the effectiveness of prepartum milking as a means of reducing mammary and umbilical edema often present at parturition.Some authors (2, 3, 9, 14) have proposed prepartum milking as a means of relieving edema.Other investigators (1, 5) have reported that prepartum milking did not affect significantly the mammary and umbilical edema present at parturition.In contrast, Smith and Keyes (12) found that prepartum milking relieved udder congestion in Holstein cows, but not in Jersey cows.If prepartum milking would relieve congestion in the udder and condition it for normal milk flow, the practice should be conducive to increased milk production for the following lactation period.Keyes and coworkers (8) found that prepartum milked cows produced more milk on the 4th day postpartum than did cows that were not prepartum milked.Dawdy and Knodt (4) determined the effect of prepartum milking on milk production by prepartum milking one half of the udder and not prepartum milking the other half.These workers found that prepartum milked halves averaged 5,061 lb. of milk, and the halves not prepartum milked averaged 4,780 lb.This is an average difference of 280 lb. of milk in favor of the prepartum milked halves for the first 7 months of lactation.Gaunya and Eaton (7) found that there was no significant difference in the yields of fat corrected milk in comparing 22 prepartum milked cows with a similar group of 22 postpartum milked cows.These same investigators found no significant difference when the yields of 21 prepartum milked cows were compared with the yields of a subsequent or previous lactation.Because of the diversity of reports on the effects of prepartum milking, it was the purpose of this experiment to further determine if the prepartum milked cows would produce a larger quantity of milk during the subsequent lactation than the cows that were not prepartum milked.EXPERIMENTAL Forty-seven cows and heifers due to freshen were divided into four groups.The cows within each breed were assigned to a prepartum milked group or a check group at random.Group I, consisting of 19 Holstein cows, was a prepartum milked group, and Group II, consisting of 8 Holstein cows, was a check group.