Effects of Dietary Vegetable Oils on Intake, Digestibility and Methane Emission from Black Goats

This study was carried out to investigate the effects of dietary vegetable oils on the nutrient digestibility and methane production of black goats. Four castrated hybrid black goats (mean body weight: 44.07 +/- 0.16 kg) were fed four experimental diets each in a 4x4 Latin square design. A control diet consisting of tall fescue hay (56%) and a mixture (44%) of corn and soybean meal was prepared and added with 3% each of soybean, coconut and palm oil, respectively for 3 treatment diets. Each experimental period consisted of a 10 days adaptation period and 4 days for the measurement of apparent digestibility of Dry Matter (DM) and of methane and carbon dioxide emissions using an open-circuit chamber system. Supplemental vegetable oil did not affect DM intake and digestibility of DM, Organic Matter (OM), crude protein. and Neutral Detergent Fiber (NDF) but the addition of the oils significantly decreased daily methane production and metabolic weight-based methane production (p<0.05). Methane production per kg intake of DM, OM and NDF was reduced by dietary coconut oil or palm oil (p<0.05). Supplemental palm oil decreased methane production per digested DM intake or digested OM intake (p<0.05). In conclusion, supplementing diets with 3% of palm oil most effectively reduced methane gas generation without affecting digestibility.