Resumen de Estimación de las emisiones de gases de efecto invernadero en vacas lecheras en pastoreo alimentadas con dietas basadas en ensilado de raigrás italiano o de leguminosas
M. Dachraoui, J.D. Jiménez Calderón, A. Martinez Fernandez, F. Vicente
The dairy sector plays an important role in the emission of greenhouse gases (GHG). Dairy cows are a significant contributor to total livestock GHG emissions with the main sources being carbon (C) loss from land use change, methane (CH4) emissions from enteric fermentation, soil nitrous oxide (N2O) emissions and manure management. For this reason, it is necessary to conduct researches in order to mitigate methane and nitrous oxide emissions from dairy cattle and crop production while trying to maintain the same daily average of milk production. The use of faba bean-rapeseed intercrop silage with organic fertilization has been evaluated as alternative to the Italian ryegrass silage fertilized with chemical fertilization in the diet of grazing dairy cows. Two trials were carried out in spring and autumn 2013 including ten lactating Holstein cows each one. The IPCC 2006 model was used to estimate the greenhouse gases emissions produced by these cows. The intake of the total mixed ration differed between autumn and spring depending on the diet fed, thus the estimation of methane also varied between seasons and diets. The intake of pasture was similar between seasons so methane emissions would be similar too. When the total intake of dry matter was considered and as the average of daily milk production was approximately maintained, the methane emission did not show any difference for both seasons and diets.
