The improvement of pork quality by means of breeding techniques

The improvement of pork quality is a continous task of pig breeders, the realization of which in practice constitutes part of performance tests and breeding value estimations. In the Hungarian system of the estimation of pig breeding value, pork quality is one of the criteria of selection. A complex parameter, the so-called pork quality score, serves for expressing pork quality. It includes three objective parameters (measured) and one qualitative parameter (estimated on a sublective basis) as expressed in scores (points). In order to survey changes that have occured in the pork quality of Hungarian pig stocks during the last years, the author and his collaborators calculated a genetic trend. The estimation comprised four purebred breeds and two hybrid populations; 1990-1997 were taken as basic years. The genetic trend of the pork quality score exhibited a stagnant character in each of the populations studied, and the rise of the linear trends did not differ from zero. From 1998 the system of the estimation of pig breeding value will change in Hungary, which will also affect pork quality. This change means the introduction of the BLUP method in practice. For the sake of BLUP adaptation, an estimation of the genetic parameters was performed also for meat quality. The inheritability of the pork quality score was found to be 0,1-0,2, which is slightly less than the value published in literature. Genetic correlations showed that the correlation between pork quality and growth vigour, as well as feed utilization, is favourable (positive), whereas there is a negative genetic correlation (exhibiting the character of a trend) between pork quality and quantity. Therefore, in the BLUP index to be introduced the weighting of the features must be formed do that it contributes to the improvement of the genetic trend of pork quality. For this purpose, the present score system (which express pork quality in a complex way) must be inevitably transformed