Effects of Dietary Energy Levels on Rumen Fermentation, Gastrointestinal Tract Histology, and Bacterial Community Diversity in Fattening Male Hu Lambs

Abstract

This study investigated rumen fermentation and histological and microbial diversity in male Hu lamb fed diets with different metabolizable energy (ME) levels (MEA, 9.17 MJ/kg, MEB, 10.00 MJ/kg, and MEC, 10.82 MJ/kg). Thirty-six male Hu lambs were randomly allotted to three treatments, and the feeding trial lasted for 67 days. Rumen fermentation results suggest that the iso-valerate had a significant effect on dietary energy level. The papillary height (PH) of rumen was the highest in the MEB group, the crypt depth (CD) was significantly increased in the duodenum and jejunum, and the villus height (VH)-to-CD ratio (VH/CD) was significantly decreased in the duodenum by increasing dietary energy levels; the VH, villus width (VW), and VH/CD also had significant differences in the ileum. 16S rRNA sequencing results showed that the operational taxonomic units (OTUs) number, the ACE, and Chao1 indices were linearly decreased by increasing dietary energy level; 24 phyla including 124 genera were identified, and the relative abundance of Papillibacter and Quinella linearly decreased by increasing the dietary energy level. Compared to MEA and MEB groups, the relative abundance of unidentified_Veillonellaceae and Anaerovibrio was significantly increased in the MEC group at the genus level. The relative abundance of the carbohydrate metabolism pathway predicted by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was linearly increased by increasing the dietary energy levels. Three metabolic pathways identified in Kyoto Encyclopedia of Genes and Genomes (KEGG) level 3 were significantly influenced as the dietary energy level increased. In summary, these results demonstrated that the dietary energy levels affected the rumen fermentation parameters, morphological structures of the gastrointestinal tract (GIT), and the composition and function of rumen microflora in male Hu sheep.

Effects of Phragmites australis Shoot Remainder Silage on Growth Performance, Blood Biochemical Parameters, and Rumen Microbiota of Beef Cattle

“…The PICRUSt prediction results showed that amino acid metabolism, carbohydrate metabolism, replication and repair, membrane transport, translation, and energy metabolism were the dominant gene families at KEGG level 2, all of which are essential for survival, growth, and reproduction of gastrointestinal microbes (44). These results were similar to our previous studies in sheep (11)(12)(13)(14)(15). Among these gene families, unexpectedly, the genes associated with metabolism of cofactors and vitamins, cellular processes and signaling, metabolism, biosynthesis of other secondary metabolites, infectious diseases, signaling molecules and interaction, nervous system, and digestive system were significantly higher in the PSR silage diet than in the mixed and corn silage diets, while lipid metabolism was dramatically lower in the PSR silage diet than in the corn silage diet.…”

“…In the current study, the concentration of GLU in the mixed group was significantly lower than in the PSR silage and corn silage treatments, while the higher ADG was observed in the mixed group. These results were inconsistent with previous studies, and this might be related to species and feed composition (11)(12)(13)(14)(15). The concentration of BUN is perceived as an effective indicator to measure the metabolism of protein and amino acid, low BUN level indicates high nitrogen metabolism capacity (21).…”

“…The PCR reactions were performed in 30-μl systems. For specific PCR amplified procedures, refer to Wang et al ( 14 , 15 ). The sequencing libraries were constructed by Ion Plus Fragment Library Kit 48 rxns (Thermo Scientific).…”

“…The sequencing libraries were constructed by Ion Plus Fragment Library Kit 48 rxns (Thermo Scientific). The Ion S5 TM XL platform to sequence was further used, and 407- to 412-bp single-end reads were generated ( 14 , 15 ).…”

Polyphenols from Fu Brick Tea Reduce Obesity via Modulation of Gut Microbiota and Gut Microbiota-Related Intestinal Oxidative Stress and Barrier Function

“…Prevention and of treatment obesity are thus very important for modern societies. Intriguingly, mounting evidence suggests that gut microbiota is related to obesity and its associated metabolic disorders. − Furthermore, transplanting the gut microbiota from obese donors to germ-free recipients by fecal microbiota transplantation (FMT) leads to obesity phenotypes in recipients, thereby verifying the cause–effect relationship between gut microbiota and obesity. , Gut microbiota dysbiosis impairs the intestinal redox state and integrity, increases endotoxin levels in the circulatory system, and induces metabolic inflammation, eventually resulting in the development of obesity. ,− Recently, certain inflammatory/pathogenic gut bacteria, including Desulfovibrio and Parasutterella, have been found to worsen obesity, whereas certain genera or species of beneficial gut bacteria, including Lactobacillus, Bifidobacterium, Akkermansia muciniphila, and Bacillus coagulans, could alleviate obesity. − Therefore, the modulation of gut microbiota dysbiosis has been presented for the prevention and treatment of obesity. − …”