Dietary supplementation of Grobiotic®-A increases short-term inflammatory responses and improves long-term growth performance and liver health in largemouth bass (Micropterus salmoides)

Grobiotic®-A (GA) is a unique prebiotic that contains a combination of partially autolyzed brewer's yeast, dairy components, and dried fermentation products. This study was conducted to dynamically investigate the effects of dietary GA (1%, G1) on growth, lipid metabolism, inflammatory responses in liver and visceral adipose tissues (VAT), and gut microbiota in largemouth bass (Micropterus salmoides). The results demonstrated that GA inclusion significantly improved growth during the 8w feeding, which could be related to higher proportion of Firmicutes and Bacillus in the gut. Dual responses of lipid metabolism in liver and VAT were observed. The different pattern of lipid metabolism induced lipid homeostasis in liver but high fat accumulation in VAT when fed G1 diet. GA inclusion induced the short-term (2w) inflammatory responses but returned to same or lower levels in a longer term (8w). GA improved liver health by decreasing hepatic glycogen and ameliorating lipid metabolism genes expression, further inhibiting the inflammatory and apoptosis responses.