LocalPork – breeding for local conditions

The LocalPork project aims to improve the efficiency of pork production in Brazil. Pigs in Brazil are usually fed a diet based on corn and soybean. Growing these pigs on a diet that includes local alternative ingredients raises a number of questions related to breeding for such an environment. First, what is the economic and environmental impact of alternative local diets. Second, what are the purebred-crossbred genetic correlations and the extent of genotype by environment interaction. Third, how to accurately predict breeding values based on crossbred performance. Performance of pigs in Brazil that are fed a reference or alternative diets was predicted and alternative diets that include Macauba or other co-products were found to improve the economic and environmental performance of pork production. Genotype by feed interaction was investigated in crossbred pigs that were fed either a corn and soybean based diet or a diet based on wheat, barley and co-products. Genetic correlations between the diets for growth and residual feed intake were found to be high. The genetic correlation between purebreds and crossbreds for residual feed intake was however found to be only moderate, 0.62. Taking into account the breed origin of haplotypes in crossbreds when predicting breeding values did not substantially increase their accuracies. We speculate that the moderate value of the purebred-crossbred genetic correlation is mainly due to GxE caused by differences in environmental factors, other than diet.