Feeding a Low-protein Maternal Diet Affects Qinghai Bamei Piglet Jejunal Microbiome-metabolome Response

Abstract

This experiment investigated the impacts of feeding a maternal low-CP concentration diet having iso-essential amino acids on new born suckling piglets intestinal microbial composition and metabolic profiles. The Bamei swine breed was selected due to high meat quality and flavor, but demonstrates slower growth rates which may be related to jejunal nutrient supply. Forty randomly selected purebred Bamei sows were divided into two groups and fed a low dietary CP (12%, LP) or a normal CP (14%, CON) diet, respectively, but formulated to contain similar (iso-) essential amino acid concentrations per current recommendations. At 21 days, 12 piglets were randomly selected from each treatment and euthanized with jejunum content samples collected. The 16S rRNA gene sequencing and mass spectrometry-based metabolomics profiling were combined as an integrated approach for evaluating the functional impact of maternal CP concentrations on piglet intestinal microbiome. Even though piglets demonstrated similar 0 to 21 d ADG among treatments, the jejunum relative weight, villus width, crypt depth and muscular thickness were increased (P < 0.05), while villus height, and villus height:crypt depth were reduced (P < 0.05) for the material LP compared to the maternal fed CON diet. Maternal CP concentrations can modify the intestinal microbial composition of Bamei suckling piglets. The relative abundances of the bacterial species Escherichia-Shigella, Actinobacillus, Clostridium_sensu_stricto_1, Veillonella, and Turicibacter were increased (P < 0.05) in the maternal LP fed diet compared with the maternal fed CON diet. Jejunal digesta metabolomics analysis indicated that several amino acids were metabolized (i.e. cys, met, tyr phe and trp), biosynthesized (arg phe, tyr, and trp), or degraded (lys) were enriched (P < 0.05) for the maternal fed LP compared with the maternal fed CON. Correlation analysis demonstrated that certain intestinal bacterial genera were highly related to the histomorphology and altered intestinal microbiota metabolites. In conclusion, maternal dietary CP concentrations in excess of protein and amino acid requirements not only altered suckling Bamei piglets histomorphology, microbial composition and function, but also modulated jejunum microbial metabolic profiles, which aids in understanding the beneficial effects when feeding a maternal LP diet on piglet intestinal health.