Methane yield and beef cattle productivity arising from the principal diets feed in the dry and rainy season of Vietnam

The effect of feeding principal beef cattle diets of Vietnam’s dry and rainy seasons on feed intake, digestibility, rumen metabolic profile, performance and enteric methane production was assessed in an experiment. A survey was conducted to classify and document the principal diets of beef cattle in three regions of Vietnam, being North, Central and Southern Vietnam across the dry and rainy season. The animals were allocated in an experiment with three treatments feeding typical diets in two seasons. Fifteen growing male crossbred cattle (Wagyu x Zebu) with average initial BW (198.9kg ± 36.9) at 11.9-18.3 months of age were subjected to measurements of CH4 output using the GreenFeed system, nutrient intake and apparent digestibility in a RCBD experiment. Daily emissions of methane and CO2 were measured using a GreenFeed device (GF; C-Lock Inc. South Dakota USA) used in the “tie stall mode”. In each season there was an effect of diet type for beef cattle on dry matter intake, animal performance and enteric CH4 emission using GF in two seasons of the year in Vietnam. There is an effect of feeding different typical diets in the seasons for beef cattle on dry matter intake, animal performance and enteric CH4 emission using GreenFeed Emission Monitoring system (GEM; C-Lock Inc., Rapid City, South Dakota, USA). The Ym values of 5.3-5.4% with the treatment in dry season and 4.4-4.5% in rainy season. For CH4 emissions expressed in g/kg DMI (MY) were 27- 35 g CH4/kg DMI. The emission factor (EF) value (kg CH4/head/year) was around 53 to 69 found in the beef cattle fed the diets in dry season and 57 to 71 in those fed diets in rainy season.