Effect of Foliage Supplementation to Heteropogon contortus Based Diets on Nutrients Digestibility, Gas and Metabolites Production in Sheep and Goat Inoculums

Abstract

In present study 20 diets were formulated using Heteropogon contortus (HC) grass with 5 tree leaves (Hardwickia binata-HB, Albizia lebbek-AL, Grewia optiva-GO, Anogeissus pendulla-AP and Leucaena leucocephala-LL) and 5 shrubs (Dichrostachys cineria-DC, Securengia virosa-SV, Zizyphus xylophyrus-ZX, Helictris isora-HI and Acacia catechu-AC) in 75: 25 and 50: 50 ratios, which were evaluated for their nutritional composition and in vitro nutrients digestibility, fermentation and gas production in sheep and goat rumen inoculums to select grass: tree leaves/shrubs species and their ratio for silipastoral system of small ruminants. Diets differed significantly (P<0.05) in CP, NDF, ADF, cellulose and lignin contents. Diets with 50: 50 and 75: 25 ratios of HC grass with foliage also differed significantly (P<0.05) in CP and fiber contents. Nutrients degradability differed significantly (P<0.05) amongst diets in rumen inoculums of both sheep and goats and were similar between HC-foliage diets in 50: 50 and 75: 25 ratios. Sheep and goats had similar nutrients degradability, while sheep and goats tended to degrade more nutrients at 75: 25 than 50: 50 ratios, respectively. Diets degradability values for DM, CP, NDF and ADF were 62.73, 57.90, 47.22 and 42.75 in sheep and 63.22, 62.06, 49.22 and 42.77% in goats, respectively. Diets differed significantly (P<0.05) for in vitro TVFA, total N and ammonia N concentration in rumen inoculum of sheep and goats. Total-N and ammonia-N was higher (P<0.05) from diets with 50: 50 ratio of HC grassfoliage diets than 75: 25 ratio. Mean TVFA, total-N and ammonia-N contents were 62.38, 40.20 and 9.31 in sheep and 63.40 meq/l, 41.72 mg/100 ml and 9.45 mg/100 ml in goat's rumen liquor. Diets differed significantly (P<0.05) in IVDMD, gas production and partition factor in both species. Gas production tended to be more in sheep (156.73) than goats inoculums (142.76 ml/g). Results showed that HC: LL and HC: GO diets are superior in nutrients content, digestibility and metabolites production, while sheep and goat exhibited relatively higher nutrients utilization and more total volatile fatty acid production at 75: 25 and 50: 50 ratios of HC-tree foliage diets, respectively.