Shiyan Qiao

Academician of Chinese Academy of Engineering; Professor of China Agricultural University; Director of National Feed Engineering Technology Research Center.

CURRENT PART-TIME POSITION: Secretary-general of National Animal Nutrition Guidance Committee; Vice President of National Feed Industry Standardization Technical Committee, etc.

RESEARCH FOCUS: Evaluation of feed nutritional value, nutritional requirements of swine, low protein diets, and feed antibiotic substitution technology and products.

MAIN ACHIEVEMENTS: Received three Second Class Prizes of the National Science and Technology Progress Award, and one Second Class Prize of the National Technological Invention Award.

In this study, three experiments were conducted to investigate the regulatory effects of the yeast supplements LEVUCELL SB and YANG on the growth performance and diarrhea incidence of weaned piglets, focusing on intestinal barrier function, intestinal microbiota, and inflammatory responses.

In Experiment 1, the effects of the yeast supplements LEVUCELL SB and YANG on the growth performance and diarrhea incidence of weaned piglets were evaluated. A total of 144 weaned piglets were randomly assigned to 4 dietary groups: the CON group (fed a basal diet), the SY group (fed a basal diet supplemented with 100 g/t LEVUCELL SB), the YD group (fed a basal diet supplemented with 400 g/t YANG), and the SY + YD group (fed a basal diet supplemented with 100 g/t LEVUCELL SB and 400 g/t YANG). The experiment lasted 28 days.

The results indicated that supplementation with LEVUCELL SB and YANG, either alone or in combination, significantly increased serum immunoglobulin G and immunoglobulin M levels, reduced serum lipopolysaccharide levels (P < 0.05), improved growth performance (P < 0.05), and reduced diarrhea incidence (P < 0.05).

In Experiment 2, the effects and mechanisms of pretreatment with LEVUCELL SB and YANG on preventing ETEC K88 infection in weaned piglets were examined. 18 weaned piglets were randomly divided into 3 groups: the CON and K88 groups (fed a basal diet), and the Y + K88 group (fed a basal diet supplemented with 200 g/t LEVUCELL SB and 800 g/t YANG). On day 14, piglets in the CON group received an oral administration of 10 mL of saline, while those in the K88 and Y + K88 groups received 10 mL of a bacterial suspension containing 5 × 109 CFU/mL.

Pretreatment with LEVUCELL SB and YANG significantly decreased diarrhea incidence (P < 0.05), increased ADFI (P < 0.05), and enhanced body weight and ADG in piglets (0.05 < P < 0.1). Moreover, this pretreatment significantly enhanced intestinal barrier function (P < 0.05) and inhibited the intestinal inflammatory response (P < 0.05). Microbiota analysis revealed that pretreatment significantly inhibited ETEC K88 colonization (P < 0.05) and increased SCFA contents in the cecum (P < 0.05). It also improved the colonic microbiota composition (P < 0.05) and restored the abundance of beneficial bacteria (P < 0.05).

In Experiment 3, the effects of adding LEVUCELL SB and YANG to the diet on alleviating ETEC K88-induced intestinal inflammation in weaned piglets were explored. 18 weaned piglets were randomly divided into 3 groups: the CON and K88 groups (fed a basal diet) and the K88 + Y group (fed a basal diet supplemented with 200 g/t LEVUCELL SB and 800 g/t YANG). On day 1, piglets in the CON group received an oral administration of 10 mL of saline, while those in the K88 and K88 + Y groups received 10 mL of a bacterial suspension containing 1.0 × 109 CFU/mL. LEVUCELL SB and YANG had growth-promoting and anti-diarrheal effects on ETEC K88-infected piglets (P < 0.05). Additionally, these supplements significantly improved the changes in serum immune indicators (P < 0.05), intestinal tissue morphology (P < 0.05), barrier function impairment (P < 0.05), intestinal microbiota changes (P < 0.05), and intestinal inflammatory factor levels (P < 0.05) caused by ETEC K88 infection.

In summary, LEVUCELL SB and YANG could effectively enhance the resistance of weaned piglets to ETEC K88 infection and improve piglet gut health by improving intestinal barrier function, modifying the composition of the intestinal microbiota, reducing serum LPS levels, and regulating the body’s inflammatory response.