Effect of different feeding methods on rumen microbes in growing Chinese Tan sheep

Abstract

We evaluated the difference between rumen bacteria in Tan sheep fed either by grazing or in a feedlot. The aim was to provide a theoretical basis for ruminant nutrition and meat quality based on rumen fermentation. Twenty-four three-monthold Tan sheep were randomly and equally divided into two groups, the grazing group and ration group. Five sheep of each group were selected for slaughter at six months of age. Ruminal contents were collected and assessed to identify rumen bacteria, based on 16S rDNA sequencing analysis. A total of 17 phyla were identified, among which Bacteroidetes, Firmicutes, and Proteobacteria were dominant in both groups. The abundance of Firmicutes was higher in grazing group than in the ration group, while that of Proteobacteria was opposite. Besides the dominant phyla differences, the abundance of Fibrobacteres, Tenericutes, Elusimicrobia, and Cyanobacteria was significantly higher in the grazing group compared with the ration group. At genus level, a total of 174 genera were identified. The abundance of Rikenellaceae_RC9_gut_group, Dialister, Lachnospiraceae_NA, Catonella, Ruminococcaceae_UCG-014, Lachnospiraceae_NK3A20_ group, and Fibrobacter in the grazing group was higher than in the ration group. However, the abundance of Succinivibrionaceae_NA was lower in the grazing group, and Succinivibrionaceae_UCG-001 showed a decreasing trend in the grazing group. The two feeding methods may influence the rumen bacterial composition, including the abundance of dominant bacteria, as well as the cellulolytic-and carbohydrate-degrading bacteria in the rumen of Tan sheep.

Diets varying in ratio of sweet sorghum silage to corn silage for lactating dairy cows: Feed intake, milk production, blood biochemistry, ruminal fermentation, and ruminal microbial community

“…The relative abundance of Succiniclasticum, Christensenellaceae_R-7_group, and Butyrivibrio_2 showed similar change patterns, with greater abundance in SS25 than in SS50; whereas the relative abundance of Ruminococcaceae_UCG-014 quadratically (P < 0.04) changed. Among these differentially abundant genera, bacteria from the genera Ruminococcaceae (groups NK3A20, UCG-005, UCG-014), are known to participate in fiber digestion in the rumen, principally of cellulose and hemicellulose (Russell and Rychlik, 2001;Fernando et al, 2010;Morotomi et al, 2012), and these bacteria are usually found in high abundance in ruminants fed high-fiber diets (Thoetkiattikul et al, 2013) or under grazing conditions (Fu et al, 2020). However, bacteria from these genera have a high functional diversity and can utilize several substrates.…”

Gut Microbiome Studies in Livestock: Achievements, Challenges, and Perspectives

“…The last decade has witnessed a mounting interest in sheep microbiome research. A recent study based on bacterial 16S has confirmed that, similar to what was found in cows, the microbial hosts may be responsible for alterations in terms of feed efficiency [ 67 ], while other works have suggested that feeding strategies may promote a more or less diverse microbial community [ 68 , 69 ]. Additionally, compositional changes in the microbiome have been observed along the GIT [ 70 , 71 ] and as an effect of parasite infections [ 72 ].…”

“…The characterization of the sheep GIT microbiome has revealed its substantial similarity in composition with that of cattle and other ruminants, with Bacteroidetes and Firmicutes making up more than 80 to 90 percent of the gut microbial community [ 67 , 69 ], followed by the phyla Actinobacteria, Proteobacteria, Spirochaetes, and Verrucomicrobia [ 68 , 74 , 82 ]. Bacterioidia and Clostridia are the dominant classes [ 75 ].…”

Unlocking the potential of insect and ruminant host symbionts for recycling of lignocellulosic carbon with a biorefinery approach: a review

“…In case of in vivo enrichment strategy a shift in the microbial community structure are caused by different feeding pattern of insects/ruminants (i.e., lignin rich or lignin poor biomass) and its association with LCB degradation capability is predominantly explored [ 21 – 24 ]. For example, an intimate co-evolution of termite gut microsymbionts ( Tsaitermes ampliceps ) and its host after feeding with different substrates (filter paper, corn stover and pine wood) were examined by high throughput 454 pyrosequencing.…”

“…On the other hand, influence of different feeding methods (i.e., feedlot and grazing) on cellulolytic microbial abundance and composition of Tan sheep rumen has been recently explored [ 24 ]. A structural variation in the rumen bacterial population has been observed, where the cellulolytic bacterial abundance is decreased, yet increases the abundance of Succinivibrionaceae family associated with starch degradation.…”