Effects of

Background: Xinjiang is characterized by extremely cold weather and significant seasonal temperature variations, and these harsh climatic conditions have led to a high incidence of diarrhea and increased mortality rates among newborn calves, resulting in substantial economic losses for the local cattle industry. Methods: In this study, a one-way experimental design was employed. A total of 45 newborn calves (Simmental♂ × Yili brown cattle♀, male, average body weight (BW) 35.58 ± 5.79 kg) were randomly allocated into five experimental groups. Each group consisted of three pens, with three calves per pen, and this allocation was carried out based on the percentage of SBWP used as a feed supplement. The diet for the five groups were as follows: group I received milk + basal diet without additives, group II received milk + basal diet + 0.005% gentamicin, group III received milk + basal diet + 250 mg/day/calf SBWP, group IV received milk + basal diet + 500 mg/day/calf SBWP, and group V received milk + basal diet + 1,000 mg/day/calf SBWP. Daily feed consumption was recorded, and BW was measured on days 1, 14, and 28 to calculate average daily gain (ADG), average daily feed intake, and feed-to-gain (F/G) ratio. Fecal samples were collected on days 1, 7, 14, 21, and 28 for microbiological analysis, and fecal scores were subjectively monitored and recorded daily by the same individual. In addition, blood samples were collected from each calf at the end of the trial for immune analysis. Results: In comparison to group I, group IV showed a significant increase in both BW and ADG. Specifically, on the 14th and 28th trial days, BW of group IV showed a significant increase of 3.95 and 4.90%, respectively ( Conclusion: The findings of this study show that the supplementation of 500 mg/day/calf SBWP to newborn calves significantly improves their growth performance, serum immunity, and intestinal microbiota structure while significantly reducing diarrhea frequency and inflammation. These findings indicate that the supplementation of 500 mg/day/calf SBWP can most effectively enhance the growth performance and reduce the diarrhea frequency in newborn calves.