Interaction of colostrum pasteurization with probiotics supplementation on health and performance of Holstein calves

The purpose of this study was to investigate the effect of simultaneous colostrum pasteurization and probiotic (PRO) use in colostrum of Holstein calves on growth performance, health, and blood metabolites in the pre- and post-weaning period. In this experiment, 60 Holstein female calves (mean birth weight 37.2 ± 2.11 kg) were used in a factorial arrangement of 2 × 2 with 15 calves per treatment. The experimental treatments were: 1. raw colostrum (RC) without probiotic supplementation (RCN), 2. raw colostrum with probiotic supplementation (RCPRO), 3. heat-treated colostrum (HC) without probiotic supplementation (HCN), and 4. heat-treated colostrum with probiotic supplementation (HCPRO). Calves were weaned at d 61 and remained until d 75 of age. The dry matter intake, rectal temperature, and fecal score were recorded daily, and body weight (BW) and skeletal growth were measured at d 0, 10, 20, 30, 40, 50, 60, 70, and 75 of age. Blood samples were taken at d 0, 1, 35, and 70 to check some blood metabolites. The heat treatment of colostrum decreased the total plate count (TPC), coliform count (TCC), and E. Coli count (TEC) levels. Calves fed RCN tended to have the greatest immunoglobulin G (IgG) concentration, and it did not differ among other treatments. Colostrum heat-treatment did not influence d 1 blood metabolites, whereas PRO decreased the total protein and globulin concentration on d 1 blood samples. Colostrum heat-treatment × probiotic supplementation interactions were observed for starter feed intake, average daily gain (ADG), and BW, with calves fed RCN having the lowest values. Starter feed intake, total dry matter (DM) intake, ADG, feed efficiency, and BW were not affected by colostrum treatment. Colostrum heat-treatment × probiotic supplementation interactions were observed for post-weaning, and overall fecal score with RCPRO calves had a lower fecal score than RCN calves. Calves fed HC had higher overall rectal temperature than calves fed RC. Regardless of PRO, DM, crude protein (CP), and organic matter (OM) digestibilities tended to be greater in HC-fed calves than in RC-fed calves. The PRO increased DM and tended to increase OM digestibility compared to those who did not receive PRO. Moreover, the RCN-fed calves had lower overall withers height and hearth girth than calves in other treatments. The results of the present study indicated that the heat treatment of colostrum reduced the TPC, TEC, and TCC and increased the nutrient digestibility of dairy calves. Moreover, the PRO supplementation did not interfere with IgG absorption from colostrum, and it did not impair passive immunity transfer. Also, the addition of PRO to RC can improve the health and performance of calves but has no effect on the performance of calves consuming HC probably due to reduced levels of pathogens.