Effects of fermentation time on in vivo/in vitro relationships.
The effects of six fermentation times, 24 through 84 h at 12 h intervals, were studied on in vivo/in vitro relationships and repeatability and variability of in vitro technique. Three stages of maturity each of bermudagrass, bahiagrass, rye-grass, sorghum-sudan, alfalfa, and orchardgrass were used. For one fermentation time for all types of forages, a 48-h fermentation demonstrated the smallest variation among runs and the least run X forage interaction. However, the optimum fermentation for perennials as a group was 60 h; and for annuals, legumes, and temperate grasses it was 36 h. Further studies in vitro compared a 48-h fermentation for all types of forage with 36 h for annuals and 60 h for perennials. Forty-eight forages, including 20 annuals and 28 perennials, were digested in vitro during three runs. With the 48-h fermentation, forages accounted for 86.43% of the total variation, runs 6.80%, and run X forage interaction 6.44%. Variation due to runs was reduced to .33%, and run X forage interaction to .90%, for a combined 36- and 60-h fermentation for annuals and perennials, respectively. Variation due to forage was increased to 98.53%.
D000821:Animal Feed / Q000032:analysis / Q000592:standards; D000818:Animals; D002473:Cell Wall / Q000032:analysis; D004040:Dietary Carbohydrates / Q000032:analysis; D004063:Digestion; D005285:Fermentation; D008297:Male; D000455:Medicago sativa; D010940:Plant Proteins / Q000032:analysis; D006109:Poaceae; D012417:Rumen / Q000502:physiology*; D012756:Sheep; D013045:Species Specificity; D013997:Time Factors
D004040:Dietary Carbohydrates; D010940:Plant Proteins