Effects of supplementation with Saccharomyces cerevisiae products on dairy calves: A meta-analysis

Abstract

Saccharomyces cerevisiae products (SCP) have the potential to promote the growth and development of the gastrointestinal tract and immunity in young livestock animals. However, the effects of SCP supplementation on calves are inconsistent among the reported studies in the literature. Hence, we performed a meta-analysis to comprehensively assess the effects of SCP on the growth performance, ruminal fermentation parameters, nutrients digestibility, ruminal histological morphology, serum immune response, and fecal pathogen colony counts in calves. We searched the Web of Science, ScienceDirect, PubMed, and China National Knowledge Infrastructure for relevant studies published up to October 1, 2021. After screening against a set of criteria, the data of 36 studies were included in our meta-analysis (2,126 calves in total). We evaluated the quality of the data using sensitivity analysis and assessed publication bias. Our meta-analysis revealed several important findings. First, SCP supplementation increased the ruminal short-chain fatty acid concentration, ruminal papilla height, and fiber digestibility, pointing toward stimulation of the development of the rumen in calves. Second, SCP supplementation increased the serum concentrations of total protein, IgA, and IgG but decreased fecal pathogen colony counts, suggesting that SCP could help calves to promote immunity (especially maintaining circulating concentrations of immunoglobulins in preweaning calves) and resistance to pathogens. Third, a subgroup analysis between preweaning and postweaning calves showed that SCP increased average daily gain and dry matter intake preweaning but not postweaning, suggesting that SCP is better supplemented to preweaning calves to achieve the best results. Forth, based on the doseresponse curve, 24 to 25 g/d might be the optimal dose range of SCP supplementation (into starter feed) preweaning to achieve the best overall effect, meanwhile, we need more studies to improve the consistency and accuracy of the dose-response curve prediction. Overall, SCP supplementation improved growth performance, rumen development, and immunocompetence in calves, particularly in preweaning calves.

Active dry yeast supplementation benefits ruminal fermentation, bacterial community, blood immunoglobulins, and growth performance in young dairy goats, but not for intermittent supplementation

“…Greater IgM concentrations in the ADY supplementation group suggested improved resistance to pathogens, consistent with a previous study of weaned beef calves ( Ma et al., 2021 ). Our recent meta-analysis also showed that S. cerevisiae products (either ADY or its fermentation products) increased serum IgG concentration by decreasing fecal pathogen colony counts, especially Escherichia coli , in young ruminants ( Zhang et al., 2022a ). Although the blood IgA concentration was slightly lower with ADY supplementation, the observed immunoglobulin concentrations were within normal physiological range, indicating no specific disease occurrence ( Zaworski et al., 2014 ; Liu et al., 2020 ; Wu et al., 2021 ).…”

“…With the ability to potentially improve rumen environment and function, ADY ( S. cerevisiae strain 1242 or proprietary strains; 8.0 × 10 10 cfu/d per animal or not indicated) was also used to alleviate the effects of subacute ruminal acidosis in lactating and/or fattening ruminants ( AlZahal et al., 2014 ; Ishaq et al., 2017 ; Elmhadi et al., 2022 ). Recently, we also found that S. cerevisiae product (either ADY or its fermentation products) supplementation could stimulate the development of the rumen and promote immunity resulting in greater dry matter intake (DMI) and average daily gain (ADG) in preweaning calves by conducting a meta-analysis ( Zhang et al., 2022a ). Villot et al.…”

“…On the contrary, the benefits of ADY supplementation can be influenced by factors including animal physiological status, basal diet, the source and dose of ADY, and supplementation strategies ( He et al., 2017 ; Amin and Mao, 2021 ; Ban and Guan, 2021 ). Our recent meta-analysis showed that the improvement in ADG by S. cerevisiae product (either ADY or its fermentation products) supplementation only presented in preweaning other than postweaning calves ( Zhang et al., 2022a ). Due to the limited number of studies investigating the S. cerevisiae products supplemented in postweaning ruminants, we were unable to determine an explanation.…”