Transcriptome Analysis Reveals That Alfalfa Promotes Rumen Development Through Enhanced Metabolic Processes and Calcium Transduction in Hu Lambs

Abstract

A healthy gut is very important for young animal development. The rumen of ruminants expands in size with the colonization of microbiota by 2 months of age. This process is promoted by alfalfa intervention. To elucidate the mechanism of this promotion, we performed transcriptomic analyses using a cohort of 23 lambs to evaluate the effects of starter diets plus alfalfa on the development of the rumen wall from the pre- to the postweaning period. The quantitative PCR analyses were used to validate selected genes that were differentially expressed in the transcriptome mapping. We found that several metabolic processes associated with rumen tissue development were affected by solid feed intake, with genes linked to the calcium signaling transduction pathway and the metabolism of pteridine-containing compounds and homocysteine metabolic process being upregulated in the group with alfalfa intervention. The results suggest that the pteridine-containing compounds and calcium signaling are targets for precise regulation of rumen development.

Transcriptional Reprogramming in Rumen Epithelium during the Developmental Transition of Pre-Ruminant to the Ruminant in Cattle

“…The transition profoundly impacts transcriptome atlas present in the rumen epithelium as the developmental status dictates differential function. The change in expression of metabolism-related genes is positively correlated with dry matter intake, indicating that the enhanced metabolic process may promote rumen development during weaning [28]. Integrative analysis of transcriptomes suggested an overall increase in carbohydrate and fatty acid-specific metabolism, such as changes in the cellular metabolic pathways after weaning, as consistent with previous reports [15,[29][30][31][32].…”

Solid diet manipulates rumen epithelial microbiota and its interactions with host transcriptomic in young ruminants

“…Transcriptomics of rumen tissue has been widely studied in ruminants to understand dynamics occurring in developing rumens associated with diet (Li et al ., 2019 ; Lin et al ., 2019 ; Yang et al ., 2019 ). A total of 109 Gb of clean data were generated, with an average of 6.44 Gb per subject.…”

Transcriptomic analysis reveals the molecular mechanisms of rumen wall morphological and functional development induced by different solid diet introduction in a lamb model

“…These metabolites are the substrates of the citric acid cycle, generating energy-containing compounds, including NADH, FADH, and ATP. They are responsible for the activation of some biological processes and might further promote rumen wall development [ 14 ]. Fatty acids are essential metabolic fuels and are vital for cell proliferation in cellular membranes [ 32 ].…”

“…The ruminal fluid samples were stored at − 20 °C until analysis for the concentrations of VFAs, ammonia nitrogen (NH 3 -N), and microbial crude protein (MCP). After recording the weight and volume of the rumen, rumen wall (3 cm × 3 cm) sample from the ventral sac was collected for analysis of rumen papilla morphology, histomorphometry microscopy, and transcriptomics as described previously [ 11 , 14 , 15 ].…”

“…This indicated that hay and concentrate may have their own unique effects on the molecular processes of rumen morphological and functional development in pre-weaning ruminants. By transcriptomics technology, emerging evidence has shown that hay feeding activated gene pathways participating in energy production [ 13 ], and hay plus concentrate starter introduction enhanced amino acid and fatty acid metabolic processes in the rumen tissue of lambs during pre-weaning period [ 14 ]. Compared to calves fed with only milk replacer before 42 days of age, calves with concentrate introduction from 42 to 56 days of age activated molecular pathways primarily related to the cell cycle in the rumen wall [ 13 ].…”