Lay Summary Experimental models have evaluated how nutrient status during pregnancy can influence the weights of calves at birth and weaning. The current study examined inherent variation in rate of body weight gain of beef heifers on pasture throughout breeding and pregnancy and its influence on performance of the calves. The association of the number of health events during the first 24 months of the life of the heifers with rate of gain during pregnancy was investigated. Increased number of health events was associated with lower rates of gain during pregnancy. Heifers that experienced a low rate of gain at any period during pregnancy produced calves that were lighter at birth and weaning. Based on these data, efforts should be made to minimize health events in replacement heifers because these health events may not only be detrimental to the performance of the heifer but to the performance of the first calf.
Cushman et al. (Thu,) studied this question.