The use of live yeast to increase intake and performance of cattle receiving low-quality tropical forages

Abstract

The objective was to evaluate the effects of a specific strain of live yeast (LY) on growth performance, fermentation parameters, feed efficiency and bacterial communities in the rumen of growing cattle fed low-quality hay. In experiment (Exp) 1, twelve Droughtmaster bull calves (270 kg ± 7.6 kg initial BW) were blocked by BW into two groups, allocated individually in pens, and fed ad libitum Rhodes grass hay (8.4% of crude protein [CP]), and 300 g/bull of supplement (52% CP) without (Control) or with LY (8 x 10 9 CFU/day Saccharomyces cerevisiae CNCM I-1077, Lallemand Inc., Montreal, Canada) for 28 d, followed by seven days in metabolism crates. Blood and rumen fluid were collected before feeding and 4 h after feeding. In Exp 2, for assessment of growth performance, 48 Charbray steers (329 kg ± 20.2 kg initial BW) were separated into two blocks by initial BW and randomly allocated into 12 pens. The steers were fed Rhodes grass hay (7.3% CP) and 220 g/steer of supplement (60% CP) without or with LY (8 x 10 9 CFU/day) for 42 d, after a two-week adaptation period. In Exp 1, fiber digestibility was calculated from total fecal collection and in Exp 2, indigestible NDF was used as marker. Inclusion of LY increased (P = 0.03) NDF intake by 8.3% in Exp 1, without affecting total tract digestibility. No changes were observed in microbial yield or in the efficiency of microbial production. There was a Treatment × Time interaction (P < 0.01) for the molar proportion of short chain fatty acids, with LY increasing propionate before feeding. Inclusion of LY decreased rumen ammonia 4 h after feeding (P = 0.03). Addition of LY reduced rumen bacterial diversity and the intraday variation in bacterial populations. Relative populations of Firmicutes and Verrucomicrobia varied over time (P < 0.05) only within the Control group. At the genus level, the relative abundance of an unclassified bacterial genus within the order Clostridiales, a group of cellulolytic bacteria, was reduced from 0 to 4 h after feeding in the Control group (P = 0.02) but not in the LY group (P = 1.00). During Exp 2, LY tended to increase ADG (P = 0.08) and feed efficiency (P = 0.10), with no effect on NDF intake or digestibility. In conclusion, S. cerevisiae CNCM I-1077 reduced the intraday variation of rumen bacteria and increased the amount of NDF digested per day. These observations could be associated with the tendency of increased ADG and feed efficiency in growing cattle fed a low-quality forage.

Changes in Digestive Microbiota, Rumen Fermentations and Oxidative Stress around Parturition Are Alleviated by Live Yeast Feed Supplementation to Gestating Ewes

“…The Verrucomicrobia family RFP12 was found to be prevalent in the rumen of high methane yielding animals [58]. In a recent trial in beef cattle fed a high forage diet [59], the same strain of S. cerevisiae that we used also had an impact on Verrucomicrobia, with a decrease in the relative abundance of this phylum. However, further work is needed, such as methane and H 2 quantifications, to explain the effects of SC supplementation on these taxa.…”

Effect of S. cerevisiae strain KA500 supplementation on feed performance, feed efficiency, and digestion ability in feedlot buffaloes

“…In general, their diet is based on grasses and leaves found in different places, especially in flooded areas. Supplementing cattle with specific strains of live yeasts has resulted in increased digestibility of (mainly low quality) fiber ( 10 , 11 ) and increases in dry matter consumption ( 12 , 13 ). Furthermore, Chaucheyras-Durand et al ( 7 ), reported that the main beneficial effect of live yeasts with regards to fiber digestibility is the ability of living yeast cells to reduce ruminal oxygen, which improves the ruminal environment and allows other microorganisms to colonize the rumen and digest fiber.…”