Effects of supplementing a commercial blend of anaerobic probiotic bacteria, MBiotix™ Calf, on the growth and health of pre-weaned and immediately post-weaned Holstein calves

Abstract Text: The objectives of these studies were to determine the effects of supplementing a blend of anaerobic bacteria on the growth and health of pre-weaned and immediately post-weaned Holstein calves. Holstein calves within 1 d of birth were randomly assigned to 1 of 2 dietary treatments (N=35). Treatments included a negative Control and MBiotix Calf (BTX) treatment, which was administered in the milk replacer and top-dressed on the starter during the pre-weaned and immediately post-weaned periods, respectively. The BTX treatment dose was 2x10⁹ CFU/d of a proprietary blend of Lactobacillus casei and Enterococcus faecium strains; however, during the first 3 d of the study the BTX calves were given a 10X dose. The study was conducted in 3 periods (n = 20 Control and n=15 BTX). Calves were individually housed and fed between 250 and 350 g depending on the period of a 22% CP and 20% fat milk replacer twice daily at 0730 and 1630. Calves had ad libitum access to a calf starter and water. Calves were individually housed until they were weaned at 56 d when they were grouped by treatment for an additional 28 d. Peripheral blood samples were collected on d 0, 7, 21, 56, 70, and 84 and analyzed for hematology. Data were analyzed as a repeated measures ANOVA with treatment, time, and treatment x time as the fixed effects and period as a random effect. Calf nested within treatment was the subject of the repeated statement. Data are reported as Control vs. BTX, respectively. There was a treatment x time interaction (P = 0.001) on calf starter intake during the pre-weaned period, whereas BTX calves began to consume more starter during the 4^th week of life, and the difference in starter intake was different (P≤0.05) during the 6^th to 8^th week of life. BTX calves were consuming more starter at weaning (1.065 vs. 1.305 ± 0.141 kg/d; P=0.025). Further, the BTX calves had greater ADG during the 84 d observation period (0.701 vs. 0.883 ± 0.079 kg/d; P = 0.016). There were no treatment or treatment x time effects on hematocrit percentage (34.3 vs. 35.9 ± 1.98%; P≥0.235). Further, there were no treatment or treatment x time effects (P≥0.178) on any hematological variable. These data indicated that supplementing MBiotix Calf improved calf starter intake and average daily gain during the pre-weaned and immediate post-weaned periods. Keywords: calf, health, nutrition, probiotic