Effect of cellulolytic Ruminococcus albus KU-F152 and non-cellulolytic Selenomonas ruminantium S137 supplementation on feedlot performance, carcass characteristics and meat quality of Holstein crossbred steers

The effect was determined of cellulolyticRuminococcus albusKU-F152 and non-cellulolyticSelenomonas ruminantiumS137 on the digestibility, feedlot performance, carcass characteristics and meat quality of Holstein crossbred steers. Eight steers were randomly inoculated withR. albusKU-F152 andS. ruminantiumS137, and eight steers were used as the non-inoculated control. The steers were fed aTotal mixed ration (TMR)diet (21:79 ratio of corn silage and concentrate) that was offeredad libitumfor 6 months. The results showed that the inoculation ofR. albusKU-F152 andS. ruminantiumS137 had no positive effect on the growth performance of Holstein steers; however, the inoculation increased the feed conversion ratio (FCR) compared with the control. The ruminal fermentation results demonstrated thatR. albusandS. ruminantiuminoculation significantly increased total volatile fatty acid (VFA), levels and increased the marbling score of meat as carcass characteristics. Regarding meat quality characteristics,R. albusandS. ruminantiuminoculation increased the meat fat and reduced the thawing loss. Furthermore, the meat of the treatment group had a significantly lower shear force (tender meat) and a lighter colour than that of the non-inoculated control.