Antibiotics are used in feed as a growth promoter for over 50 years. However, the practice has become increasingly controversial, and was banned in the European Union, United States of America. Since 2017, China Ministry of Agriculture (MOA) has gradually reduced types and doses of antibiotics allowed in feed with the intent to ban the usage of antibiotics in feed additives by 2020. Thus, finding safe and effective alternatives to traditional antibiotics that will allow swine producers to maintain the competitive advantages provided by antibiotics without the stigma associated with their use.

As the most stressful phase in the life of pigs, weaning is commonly associated with post-weaning syndrome including diarrhea, growth retardation and intestinal barrier disruption. Researchers from the Institute of Subtropical Agriculture (ISA) of the Chinese Academy of Sciences found that yeast glycoprotein (YG) affected growth performance, intestinal mucosal morphology, immune response and colonic microbiota in weaned piglets. A total of 240 weaned piglets (d 23 ± 2) from 16 pens (15 piglets/pen) were randomly allocated to an antibiotics group (25% Quinocetone 200 mg/kg and 4% Enduracidin 800 mg/kg of the basal diet), or a YG group (800 mg/kg YG of the basal diet), respectively. The researchers found that piglets fed diets containing YG increased average daily gain and decreased F/G (P < 0.05) when compared with the antibiotics group.

Histological evaluations showed that YG contributed to the improvement of the intestinal development via increasing villous height (P < 0.05) and the villous height to crypt depth ratio (P < 0.01), and decreasing crypt depth (P < 0.01) and villous width (P < 0.05) in the ileum. They also found that YG was conducive to improvement of the intestinal development via upregulating the m-RNA expression of occludin gene (P < 0.05) in the duodenal and jejunal mucosa. YG supplementation downregulated the m-RNA expression of IL-12 gene (P < 0.05), upregulated the m-RNA expression of Hsp-70 gene (P < 0.05) in the duodenal and ileal mucosa. In addition, YG supplementation downregulated the m-RNA expression of Hsp-70 (P < 0.05) and IFN-γ gene (P < 0.05), upregulated the m-RNA expression of Hsp-90 gene (P < 0.05) in the jejunal mucosa.

Moreover, YG supplementation increased the relative abundance of Lactobacillus (P < 0.05) in the genus level and decreased the content of acetate (P < 0.05).
The researcher found that YG would be a potent alternative to prophylactic antibiotics in improving the gut health in weaned piglets.

The study entitled “Effects of dietary supplementation with yeast glycoprotein (YG) on growth performance, intestinal mucosal morphology, immune response and colonic microbiota in weaned piglets” was published in Food and Function as a Cover article, details can be found at http://xlink.rsc.org/?DOI=C8FO02327A.

It was supported by the National Key Research and Development Program of China.

Contact: WU Xin

E-mail: wuxin@isa.ac.cn

Institute of Subtropical Agriculture, Chinese Academy of Sciences