Resumen de Interacción genotipo X sistema de producción para calidad de canal y carne en cerdos ibéricos de montanera y cebo de campo
Juan M. García Casco, M. Muñoz, M.C. Rodríguez, L. Silió López
A selection index for carcass composition and quality traits is suggested for Iberian pigs fattened with two different free-range systems: montanera (acorn feeding) and cebo de campo (feeding mainly based on cereals and vegetables). Heritabilities and genetic correlations were estimated from two data sets with 4,348 records of montanera pigs and 1,818 records of cebo de campo pigs, with a multitrait animal model that included carcass composition and quality traits expressed in both systems as different traits. A selection index was built with the estimated breeding values considering carcass composition traits by their economic weight, and they were calculated by means of the partial derivative of the profit function. Otherwise, the economic weight of intramuscular fat was obtained using the theory of optimum traits. The estimates of heritabilities showed higher values in cebo de campo system (0.43 - 0.66) than in montanera system (0.24 - 0.33) with genetic correlations between same traits recorded in different systems of moderate values (around 80%) and negative correlations between premium cuts and intramuscular fat. Pearson and Kendall ranking correlations of breeding values and selection index were calculated in a subset of 20 sires with offspring in the both system in order to show the interaction between genetic evaluation and production systems.
