Early prediction of phenotypic survival to the second lactation in Dutch and Flemish Holstein heifers using genomic and phenotypic data

Abstract

Due to uncertainty about survival and future performance of replacement heifers, many farmers rear a surplus of heifers. By predicting survival at an early age, uncertainty about heifer survival could be reduced, and fewer replacement heifers would be needed. A dataset of 1907 Holstein heifers born between 2012 and 2013 with 50 genomic breeding values (GEBV) and various phenotypic variables was used to predict survival to second lactation, at two moments in life; at birth, and at age of 18 months. While it was not possible to reliably predict survival outcome of individual heifers, the surviving heifers ranked higher on average than non-surviving heifers at birth (0.87 (SD = 0.047) vs 0.84 (SD =0.059), and at 18 months (0.89 (SD =0.066) vs 0.85 (SD = 0.080). The best prediction of survival in both cases was obtained by combining phenotypic information and gEBV, demonstrating the potential for farmers to combine both information sources to predict the probability of survival for their replacement heifer management. Keywords: phenotypic prediction, dairy cattle, surviva