The Comparative Reproductive Performance of Nursed Cows and Milked Cows

Abstract

In a herd of Milking Shorthorns the average length of service period was 152 days in nursed cows and 94 days in cows milked twice a day. The interval from calving to first estrus was approximately 30 days longer in the nursed cows and the interval from first service to conception was 27 days longer. The average length of interval from calving to first corpus luteum was 53 days in the nursed cows and 36 days in the milked cows. Nursed cows averaged 0.65 more quiet ovulations before the first post-partum estrus and had a longer interval from first corpus luteum to first estrus (30 days compared to 17 days in the milked). The number of services required per conception was 1.84 for the nursed cows and 1.54 for the milked cows. A larger proportion of the milked cows settled at the first service (71% compared to 51% for the nursed cows). The interval between services averaged 58 days in the nursed cows and 36 days in the milked cows. The results indicate that the reproductive efficiency of cows milked twice daily is considerably better than that of cows nursing calves. Copyright © . .