Predicted responses to selection from indices incorporating feeding pattern traits of pigs using electronic feeders

The main aims of this study were to predict the increase in the accuracy of selection and the response to selection achieved by including feeding patt ern traits, such as number and size of meals, as selection criteria in indi ces to improve growth rate, lean content of the carcass and food conversion ratio. Generic and phenotypic parameters obtained for pigs given food ad l ibitum using single space electronic feeders were used to construct the ind ices. The predicted generic gain in the inner increased far indices with mo re feeding pattern traits. The inclusion of part test records for feeding p atterns resulted in similar predicted correlated responses and predicted ac curacy of selection to those using whole test records of daily food intake. The inclusion of feeding patterns as selection criteria resulted in indice s that were less robust to inaccurate parameter estimates. It was concluded that feeding pattern traits could be used to improve the predicted accurac y of selection for the efficiency of lean growth but the most effective and robust index would include only daily gain, backfat depth, daily food inta ke and mean number of visits to the feeders per day. These traits may also be useful in reducing the length of the test period necessary for accurate measures of food intake, so increasing the potential intensity of selection using a given number of feeders.