162 The Effects of a Saccharomyces Cerevisiae Fermentation Product on the Digestibility of an Annual Rye Grass Hay Based Finishing Diet for Lambs

Abstract

Abstract Interest in the use of yeast fermentation products has grown in recent years as a natural feed additive for the growth of ruminants in a feedlot setting. The purpose of this study was to determine if the supplementation of a Saccharomyces cerevisiae fermentation product (SCFP) had an effect on apparent digestibility in Katahdin lambs offered an annual ryegrass hay-based finishing diet. Six Katahdin wethers (n = 6) were divided into two groups CON and TRT and placed into individual metabolism crates in a temperature-controlled room, (21.1° C), and fitted with fecal collection bags. Lambs were offered a TMR diet that was formulated to be isocaloric and isonitrogenous at 14% CP, and annual ryegrass hay based with a top dress of ground corn to be used as a carrier. The TRT received the yeast supplement at a rate of 4g/head/day. The diet was offered ad libitum with orts collected daily to maintain a 5% refusal rate. Lambs were housed in the metabolism crates for 1-wk before the start of the study for adjustment, followed by 4 days of data collection. Feed, orts, fecal, and urine samples were collected and recorded daily during the collection period for each wether and compiled by animal for chemical analysis of DM, NDF, ADF, CP, and ether extract. Indigestible ADF was used as a digestibility marker to determine apparent digestibility. Data were analyzed by PROC GLM for statistical significance. There was no statistical significance found for apparent digestibility of DM (CON=64.6 ±2.5; TRT=63.4±2.5), CP (CON=65.0 ±2.1; TRT=65.9±2.1), NDF (CON=41.2±1.9; TRT=43.0±1.9), or ADF (CON=26.1 ±4.7; TRT=33.8±4.7) between the two groups (P > 0.05). This study concluded that the supplementation of a SCFP had no significant effect on the apparent digestibility of Katahdin wether lambs that were offered an annual ryegrass hay-based finishing diet.