Factor de emisión de metano entérico para vacas Holstein lactantes en la zona norte de Antioquia - Colombia

摘要

The objective of this work was to determine an enteric methane emission factor in dairy cows in the Colombian tropics. Sixteen Holstein lactating cows were used. The animals were fed with Kikuyu grass ad libitum and supplemented with concentrated feed that was offered at the milking, 1 kg per 3.5 liters of milk produced. The animals were milked daily at 5 and 14 hours. The variables evaluated were: methane production in respirometric chamber, dry matter intake, production and composition milk. Methane production was not constant throughout the day. Methane production increases after milking, when animals received concentrate supplementation (5 and 14 hours). A notable decline in methane production was recorded between 22 and 5 hours, this period coinciding with a lower intake of dry matter and a higher presence of structural carbohydrates in the rumen, with slow fermentation rates. In this study, 4.9 ± 1.2% of the gross energy consumed was lost in the form of methane (Ym), which is below the suggested value of 6.5 ± 1.0% for dairy cows in developing countries. In this study, 4.9 ± 1.2% of the gross energy consumed was lost in the form of methane (Ym), which is below the recommended value of 6.5 ± 1.0% for dairy cows in developing countries. The emission factor expressed in kg of methane / animal / year found in this work was 104.9 ± 10.6 in comparison with for Latin America and North America factors (72 and 128 kg of methane / animal / year, respectively). The energy lost as methane (Ym) during enteric fermentation was overestimated in 24.6% by the IPCC (2006). The inappropriate use of emission and conversion factors affect inventories of greenhouse gas emissions.