Methane is an important greenhouse gas associated with livestock, especially ruminants. The aim of this study was to evaluate whether the addition of red grape pomace by‑product ('Tempranillo' variety) to the diet of fattening lambs reduces methane emissions and to verify whether this dietary modification influences the production and quality parameters of the final product. Twelve Merino lambs divided in two batches were used: control (conventional feed concentrate) and experimental (substitution of 5 % barley concentrate by 5 % red grape pomace). Daily methane concentrations were determined using a portable laser methane detector. On the other hand, the consumption and weight of the animals were monitored. Finally, the colour, pH, moisture, lipid oxidation, intramuscular fat, and fatty acid profile of the longissimus dorsi were analyzed. The results showed a decrease in the mean methane concentration during eructation (27.77 ppm.m vs. 52.30 ppm.m) in the experimental batch, a lower frequency of eructation in this batch compared to the control, and a reduction in the maximum methane emitted during respiration and eructation (54.15 ppm.m vs. 101 ppm.m) could also be observed. The production parameters, as well as the meat quality parameters were not altered by the diet modification, therefore, the incorporation of 5 % red grape pomace in the concentrate for fattening lambs has a positive effect on the environmental impact, with no other negative repercussions. However, it is necessary to extend the study period as well as the number of animals to obtain more consistent conclusions.

Barraso C., García A., López‑Parra M.M., Rodríguez P.L. (en prensa). Incorporación de orujo de uva al concentrado de corderos de cebo, efecto sobre las emisiones de metano. Estudio preliminar. ITEA‑Información Técnica Económica Agraria. Vol. xx: YY-YY. https://doi.org/10.12706/itea.2024.011