Abstract
This study aimed to investigate the changes in abomasum transcriptome and the associated microbial community structure in young calves with artificially dosed, adult rumen contents. Eight young bull calves were randomly dosed with freshly extracted rumen contents from an adult cow (high efficiency (HE), n = 4), or sterilized rumen content (Con, n = 4). The dosing was administered within 3 days of birth, then at 2, 4, and 6 weeks following the initial dosing. Abomasum tissues were collected immediately after sacrifice at 8 weeks of age. Five genera (Tannerella, Desulfovibrio, Deinococcus, Leptotrichia, and Eubacterium; p < 0.05) showed significant difference in abundance between the treatments. A total of 975 differentially expressed genes were identified (p < 0.05, fold-change > 1.5, mean read-counts > 5). Pathway analysis indicated that up-regulated genes were involved in immune system process and defense response to virus, while the down-regulated genes involved in ion transport, ATP biosynthetic process, and mitochondrial electron transport. Positive correlation (r > 0.7, p < 0.05) was observed between TRPM4 gene and Desulfovibrio, which was significantly higher in the HE group. TRPM4 had a reported role in the immune system process. In conclusion, the dosing of adult rumen contents to calves can alter not only the composition of active microorganisms in the abomasum but also the molecular mechanisms in the abomasum tissue, including reduced protease secretion and decreased hydrochloric acid secretion.
Highlights
The ruminant stomach has four functional compartments: rumen, reticulum, omasum, and abomasum for the efficient use of plant materials
There were 975 genes differentially expressed between the control group (Con) and high efficiency (HE) groups (p < 0.05 and fold-change > 1.5) with 348 up-regulated genes (URGs) and 627 downregulated genes (DRGs) in the HE group in comparison to the Con group (Table S1)
Our study provided a transcriptome snapshot of the molecular mechanisms in the abomasum of young calves dosed with rumen content collected from adult cow
Summary
The ruminant stomach has four functional compartments: rumen, reticulum, omasum, and abomasum for the efficient use of plant materials. The abomasum is the last stomach compartment of the ruminant stomach It is a secretory stomach, anatomically and functionally similar to the stomach of non-ruminants. Because it is a connection between the pre-intestinal and digestive tract in ruminants, the abomasum plays a major role in the acid hydrolysis of microbial and dietary proteins, facilitating further digestion and absorption of proteins in the small intestine. Much more work is needed to advance the full understanding of the digestive function of abomasum and its contribution to the health and efficiency of gastrointestinal tract (GIT) in ruminants
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
