Essential oil effects on rumen fermentation, animal performance, and meat quality of beef steers

Efficiency in ruminants has historically been improved by using antibiotics and ionophores to alter rumen fermentation. Nutritionists, however, have begun searching for alternative rumen modifiers due to the negative attention received by non-therapeutic antibiotic use. Plant extracts, like essential oils, are being explored as a potential alternative to alter fermentation and improve growth and efficiency in ruminants. Essential oils are naturally occurring, secondary metabolites that can be distilled or extracted from most plants and possess antimicrobial properties. Next Enhance ® (NE, Novus International Inc.) is comprised of garlic (diallyl disulfide) and cinnamon (cinnamaldehyde) extracts; both have demonstrated the ability to modify fermentation. A series of experiments was conducted to determine how feeding NE affects in vitro fermentation, site and extent of nutrient digestion, feedlot performance, carcass traits, meat quality, and consumer sensory characteristics of LM steaks from beef steers. The first experiment in this thesis examined how feedlot steer performance and carcass traits were affected by NE feeding. ADG and G:F were improved early in the feeding period by 150 mg·hd −1 ·d −1 targeted NE inclusion. DMI, overall ADG, and overall G:F were not