Effects of Saccharomyces Boulardii Cell Wall Polysaccharide on Growth Performance, Serum Immunity and Fecal Microorganisms of Newborn Calves

Mengjian Liu^1,2*Haina Yin^1,2Xucheng Mo³Wenshu Zhu^1,2Wenshuai Zen^1,2

• ¹Xinjiang Agricultural University, Ürümqi, China
• ²School of Animal Science, Xinjiang Agricultural University, Urumqi, Xinjiang Uyghur Region, China
• ³Animal Health supervision station of Changji National Agricultural Science and Technology Park, Changji, China

The harsh climatic conditions in Xinjiang, characterized by extreme cold weather and significant seasonal temperature variations, have led to elevated incidence of diarrhea and increased mortality rates among newborn calves, resulting in substantial economic losses for the local cattle industry. Saccharomyces boulardii Cell Wall Polysaccharide (SBWP), a natural prebiotic, has emerged as a promising alternative to conventional antibiotics for mitigating systemic inflammation, diarrhea, and mortality in livestock production. Therefore, the study aimed to investigate the effects of SBWP supplementation on growth performance, diarrheal frequency, serum immunity, and intestinal microbiota in newborn calves.In comparison to the Group I, 1) Group IV exhibited a significant increase in both the body weight (BW) and the average daily gain (ADG). Specifically, on the 14th and 28th trial days, the BW of group IV exhibited a significant increase of 3.95% and 4.90%, respectively (P<0.05). Similarly, the ADG of group IV exhibited a significant increase of 28.49% during the 1-28 trial day (P<0.05). The F/G ratio of group IV decreased significantly by 22.89% during the 1-28 day trial period (P<0.05). No statistically significant difference was observed between group IV and group II in terms of BW, ADG, DMI, and F/G (P>0.05). 2) The fecal score and diarrhea rate in group IV were significantly reduced by 31.62% and 18.54% (P<0.05). No statistically significant difference were observed between group IV and group II (P > 0.05). 3) The levels of IgG and IL-10 in group IV were significantly enhanced by 51.97% and 45.45% (P<0.05), while the content of IL-1, IL-6, and TNF-α was significantly decreased by 30.47%, 28.17% and 25.49% (P<0.05). 4）A decreasing trend in the number of Escherichia coli and Clostridium perfringens was observed in the fecal microbiota samples from group IV, while an increasing trend in the growth of Lactobacillus and Bifidobacterium was noted. 5) The supplementation of 500 mg/day/calf SBWP significantly enhanced the β-diversity indices and demonstrated a trend toward increasing α-diversity in the fecal microbiota of newborn calves, in contrast to the detrimental effects induced by 0.005% gentamicin. 6) Furthermore, 500 mg/day/calf SBWP significantly elevated the relative abundance of Lactobacillus and reduced Escherichia-Shigella.