Table 1. Factors affecting rumen microbiota in Hanwoo cattle

Factor	Diet	Animal	Rumen microbiota composition	References
Rumen sampling method	80% concentrate, and 20% mixed forage (45% tall fescue, 45% orchardgrass, and 10% Kentucky bluegrass)	Brown Hanwoo steers (605 ± 18 kg)	No difference between cannulation and stomach tube methods Dominant phyla: Bacteroidetes, Firmicutes Dominant genera: Succiniclasticum, Butyrivibrio, Ruminococcus, Selenomonas	[8]
Cannulation surgery	Total mixed ration (TMR)	Brown Hanwoo steers (341 ± 20 kg)	Some major taxa and microbial diversity were affected by rumen cannulation surgery. Dominant phyla: Bacteroidetes, Firmicutes Dominant genera: Prevotella, Succiniclasticum, Treponema, Butyrivibrio, Saccharofermentans, and Ruminococcus	[7]
Heat stress	60% concentrate, and 40% rice straw	Brown Hanwoo steers (235 ± 24 kg)	Ruminococcaceae decreased by heat stress Lactobacillaceae increased by heat stress Dominant phyla: Bacteroidetes, Firmicutes Dominant families: Prevotellaceae, Paraprevotellaceae, Porphyromonadaceae, Ruminococcaceae, Veillonellaceae, Lachnospiraceae, Erysipelotrichaceae, Clostridiaceae, Christensenellaceae, Mogibacteriaceae, Succinivibrionaceae Dominant methanogen: Methanobrevibacter	[13]
Feeding system	85% concentrate and 15% forage (separate feeding) Total mixed ration	Brown Hanwoo steers (507 ± 67 kg)	Prevotellaceae was abundant in the separate feeding group Rikenellaceae was abundant in the TMR group Dominant phyla: Bacteroidetes, Firmicutes Dominant methanogen: Methanobrevibacter	[14]
Breed	Total mixed ration	Brown and jeju black Hanwoo steers (400 ± 24 kg)	Ruminococcus was greater in brown Hanwoo steers than in jeju black Hanwoo steers Dominant phyla: Bacteroidetes, Firmicutes	[15,16]
Marbling content	89% concentrate and 11% forage	Brown Hanwoo steers (an average weight of 626 kg)	Dominant taxa in high-marbling score group: RFP12, Verrucomicrobia, Oscillospira, Porphyromonadaceae, Paludibacter Dominant taxa in low-marbling score group: Olsenella Dominant phyla: Bacteroidetes, Firmicutes Dominant genus: Prevotella	[17]