Effects of supplementation of vegetable oil and tannin on methane gas emission in raising cattle
The experiments were conducted on 12 Red Sindhi crossbred cattle at 15-16 months of age for the 90-day trial in order to determine methane emission by addition of vegetable oil and tannin into feed. Cattles were housed in farm housing condition then were individually arranged to respiratory chambers to measure methane gas emissions. The diets consisted of basal diets with addition of 0.3 and 0.5% tannin; 1.5 and 3% vegetable oil on dry matter basic. Animals were fed ad libitum with 15 days of diet adaptation prior to testing. Results showed that the effect of different levels of tannin supplementation on the level of CH4 and CO2 emissions of experimental cattle was from 168.28 to 180.88 liters/day, there was a significant difference in the amount of methane released (P<0.05). Specifically, the control (without added tannin and vegetable oil) had the largest emitted methane at 180.88 liters/day and Treatment 2 (added tannin at 0.5% DM, vegetable oil at 3% DM) has the smallest methane gas emissions of 168.28 liters/day, lower than the control about 6.97%. When increasing tannin and vegetable oil supplement level, methane gas emissions tended to decrease. When supplemented with low tannin 0.3% DM and vegetable oil 1.5% DM (in Treatment 1) the amount of methane emitted was 176.05 liters/day and 125 g/day; However, when supplemented with high levels of tannin 0.5% DM and vegetable oil 3% DM the amount of methane emitted was 168.28 liters/day and 119.48 g/day. It was concluded that different tannin and vegetable oil supplements have a significant effect on the level of methane emissions of experimental cattle, as the supplement level increases, the methane emissions tend to decrease (P<0.05). The emission intensity of CH4 tends to decrease with increasing dietary supplement of tannin and oil, however, when supplementation is at high level, the emission intensity tends to increase.
Use diets supplemented with 0.5% DM of tannin, 1.5% DM of vegetable oil to raise cattle for the best growth. Moreover, it has the good effect by decrease significantly methane gas emissions, contributing to reducing environmental pollution from livestock.
