The Use of Dairy Cull Cows as Foster Mothers

Abstract

A trial to determine the feasibility of using a cull dairy cow to rear her own calf and an additional adopted one was conducted at the Corozal Substation of the Agricultural Experiment Station, Mayagüez Campus, of the University of Puerto Rico. The data indicates these dairy culls can rear both calves satisfactorily to 8 months of age. The two groups in the experiment were subjected to two different treatments: (I), weaning the adopted calf at 4 months of age and feeding 4 pounds of concentrate, supplementary to grazing, for the subsequent 4 months while leaving their own calf with the dam until 8 months of age; and (II), nursing of the cow by both calves until weaning at 8 months of age. The analysis of the data indicates no benefit from weaning calves at 4 months of age. Although the adopted calves weaned at 4 months of age were 11.95 pounds heavier at 8 months than those that continued to nurse their foster mother until 8 months of age, costs of concentrate feeding and extra labor requirements more than offset the extra weight gains. The statistical analyses of the data for weight gains showed a significant difference in favor of own calves over adopted ones at all ages. The sex of calf had no effect on any of the weight gain comparisons. The rate of gain of the adopted as well as the own calves is presented. There were no adoption problems. The average calving interval for cows that freshened at least two times was 395.24 days. Twenty three cows showed reproduction failures, nine of which never freshened.