Growth-Promoting Effects of Zhenqi Granules on Finishing Pigs

SIMPLE SUMMARY: With the ban on using antibiotics as animal growth promoters in many countries, developing alternative growth promoters is of urgent need. In this study, we investigated the growth-promoting efficacy of a traditional Chinese medicine (TCM) formula Zhenqi granules (ZQ) in pigs. We show that ZQ has a significant growth-promoting effect in pigs, especially during the finishing stage. To further explore the possible mechanisms of growth promotion, transcriptomics analysis with liver and skeletal muscle tissues are performed that reveals that genes involved in collagen biosynthesis and lipid biosynthetic processes are differentially expressed in the pigs administrated with ZQ. We report for the first time that a TCM formula ZQ has significant growth promotion efficacy in pigs and reveals that it may promote animal growth by regulating skeletal myogenesis and fat deposition. ABSTRACT: Developing nonantibiotic livestock growth promoters attracts intensive interest in the post-antibiotic era. In this study, we investigated the growth-promoting efficacy of Zhenqi granules (ZQ) in pigs and further explored the possible mechanisms by transcriptomics analysis. Weaned piglets (52 days old with an average body weight of 17.92 kg) were fed with diets supplemented with different doses of ZQ (0 g/kg, 1 g/kg, and 2 g/kg) for 30 days and continued observations for an additional 32 days after removing ZQ from the diets. Compared with the control group, the average daily gain, carcass weight, average back fat thickness, and fat meat percentage of the group supplemented with 1 g/kg of ZQ showed a significant increase, and the feed/gain ratio was lower. The group supplemented with 2 g/kg of ZQ also showed a significant increase in average daily gain and average backfat thickness. A transcriptomics analysis revealed that the supplementation of ZQ at 1 g/kg upregulated the expression of genes related to collagen biosynthesis and lipid biosynthesis in skeletal muscle and liver. This effect was primarily through upregulating the mRNA levels of structural proteins and lipid-related enzymes. This study demonstrates the growth-promoting efficacy of ZQ and provides some insights of the mechanism of growth promotion.