Date Full Report Received08/01/2007
Date Abstract Report Received08/01/2007
Funded ByNational Pork Board
It is hypothesized that a genetic selection for improved growth rate will result in a significant change in fresh pork quality. This study focused on two objectives. The first objective of this study is to determine the extent to which selection for improved growth rate influences pork quality. It is important to understand if this selection practice will have a negative impact on pork quality similarly to selecting for improved lean growth, or if this selection practice will possibly result in a positive impact on pork quality. The results of this objective will determine if this is a selection practice that can be successfully used by the industry without having a detrimental influence on pork quality. If there are variations in pork quality as a result of selecting for improved growth rate, it is important to understand the causes of the quality variations and determine how relationships between pork quality traits may have changed as a result of the selection method. The second objective of this study is to determine the extent to which selection for improved growth rate influences relationships between pork quality traits that can be used to explain variations in ultimate pork quality. Understanding how these relationships are influenced will lead to a further understanding of how these traits can be used to decrease the amount of variation in pork quality and ultimately be beneficial to the industry by increasing consumer acceptance of fresh pork products.
The findings of this study show that selection for improved growth rate can be implemented as a successful selection method without having a detrimental impact on pork quality. They also highlight the importance of genetic selection on pork quality variations. As a result, it is important to account for the genetic predisposition of the animal in addition to the selection practice used as both are of importance in determining ultimate pork quality. In addition, they highlight the importance of not using a single trait selection method as the trait may be changed as a result of the genetic background of the animal. Combining selection practices with the genetic background of the animal potentially changes how many factors interact with each other and can account for subsequent differences in pork quality traits such as water-holding capacity and sensory attributes.
Overall, the findings demonstrate that this selection practice can be used to significantly reduce the days necessary for pigs from these sires to reach 125 kg without having a negative influence on pork quality. Future work addressing the causative agents controlling the variation in quality will be beneficial when selecting progeny for improved growth rate performance. The results of the genetic marker testing document a clear link between growth, metabolism, meat quality and meat composition. Genetic markers (MC4R, PRKAG3) have major effects on pork quality and their use in marker-assisted selection within pig populations will be effective in improving product characteristics. Moreover, the genetic background of the animals should be considered for the genotypic analysis and prediction of response to selection.