Effects of types and doses of yeast on gas production and in vitro digestibility of diets containing maize (Zea mays) and lucerne (Medicago sativa) or oat hay

Abstract

Yeast products for ruminants based on Saccharomyces cerevisiae increase the number of cellulolytic bacteria (Wallace & Newbold, 1993; Alzahal et al., 2014), and are associated with a higher rumen pH promoted by the yeast, which favours the growth of fibrolytic bacteria (Fibrobacter and Ruminococcus) and lactate-utilising bacteria (Megasphaera and Selenomonas; Pinloche et al., 2013). They have thus been regarded as rumen pH stabilisers (Chaucheyras-Durand et al., 2008; Desnoyers et al., 2009). In most in vivo evaluations of commercial products that contain Saccharomyces cerevisiae, researchers confirmed that the amounts of live cells were described by the commercial manufactures (Crosby et al., 2004; Pinloche et al., 2013; Ahmed et al., 2015; Pienaar et al., 2012)