The aim of this study was to investigate the effects of probiotics on pre-weaning performance, muscle, and fat deposition and serum metabolite profiles in male and female Senepol calves. Thirty new-born Senepol calves, 15 males and 15 females, were randomly allocated to the following treatments: CON a control group that received the basal creep feeding diet and PRO animals that received the basal diet with addition of 2 g/100 kg of body weight (BW) of probiotic. PRO supplementation did not change the DMI but increased average BW, final BW, ADG relative to animals fed CON. Additionally, PRO improved LMA and marbling. Regardless of the serum metabolite profile, the important metabolites for discriminating PRO and CON were glutamine, leucine, creatine, acetate, creatinine, arginine, glutamate, hippurate, glycerol, carnitine, lactate, carnosine, myo-inositol and histidine. According to gender, males had an overabundance of glutamine, glycerol, isoleucine, creatinine and glucose, whereas females had an overabundance of acetyl carnitine, glutamate and carnitine. In conclusion, the addition of PRO in the pre-weaning diet of calves increases performance, weight at weaning and muscle and fat deposition on the carcass, improving proteins and fatty acid metabolism, the immune system response and rumen development.
Keywords: Nuclear Magnetic Resonance; Senepol; marbling; metabolomics; probiotic.