Effect of Milking Intervals on the Rate of Milk and Fat Secretion

Abstract

Fifteen high-producing Holstein and Brown Swiss cows in early lactation were milked at 4,- 8-, 12-, 16-, and 20-hr. intervals. Ten I.U. of oxytocin were injected at the beginning and end of each interval to obtain residual milk. Each interval was repeated three times and each series of intervals was separated by a 12-hr. interval. The rates of milk, fat, and solids-not-fat secretion were linear for intervals up to and including 12 hr. Significant reductions in rates of secretion of these components were found at 16- and 20-hr. intervals between milkings as compared to the 4-, 8-, and 12-hr. intervals. The butterfat percentages for the different intervals were nearly the same, except for the 4-hr. interval, where an unexplainable increase took place. The solids-not-fat content was the same for all intervals. Preceding long intervals caused a depression of milk secretion during the 12-hr. intervals, but caused a marked increase in butterfat percentages. © 1960, American Dairy Science Association. All rights reserved.