Effects of butyrate supplementation in antibiotic-free milk replacer and starter on growth performance in suckling calves.

The aim of this study was to evaluate butyrate supplementation of antibiotic-free milk replacer and starter on growth performance in male Holstein calves. Twenty-nine calves were divided into two groups. Group C (n = 13) was fed antibiotic-free milk replacer without supplementation, and Group B (n = 16) was fed antibiotic-free milk replacer supplemented with butyrate (1.6 % DM of Gustor BP70 ). Starter in Group B contained 0.3 % DM of Gustor BP70 . The intake of milk replacer was lower in group B than in C (p = 0.07 for the treatment x week interaction). Body weight (BW) and heart girth (HG) in group B was higher than in C during the experimental period (p = 0.07 and 0.01 for the treatment × week interaction, respectively). The duration of the weaning period in group B was shorter than in group C (p = 0.02). β-hydroxybutyrate (BHBA) was higher in group B than in C (p = 0.04). Insulin like growth factor-1 (IGF-1) concentrations tended to be higher in group B than in C (p = 0.07 for treatment × week interaction). Our results show that butyrate supplementation in antibiotic-free milk replacer and starter exerted positive effects on growth performance in suckling calves.