Exploratory study of the potential use of a novel pooled phenotype to select against boar taint

Meat quality traits are economically important in pig production. Breeding strategies can help prevent meat defects such as boar taint, usually characterized by quantified indole, skatole and androstenone (ISA) in back fat. This exploratory study investigated the genetic potential of a novel boar taint phenotype, pooling volatile organic compounds (VOCs), which were recently identified as phenotypically discriminant. Fat samples were collected from 1272 Pietrain × Landrace crossbred boars. Phenotypes for boar taint on these samples were: lab sensory score (LSS; n = 1269), ISA quantification (n = 308), and VOC profiles (n = 127). Given the limited amount of data, a selection index-based approach was used to pool traits in trait groups, ISA and VOC, considering LSS as reference trait. (Co)variance components were estimated with a full multi-trait model, and index equations were adjusted to account for uncertainty in estimated parameters. Index coefficients were then applied to ISA and VOC phenotypes to generate two pooled phenotypes, ISA and VOC indices. Estimates from the 3-trait model (LSS, ISA index and VOC index) confirmed high expected correlations with LSS. Genetic parameter estimates showed higher significance demonstrating the interest of pooling multiple partially informative traits together. Moreover, using the VOC index would generate a higher expected correlated genetic response in LSS (192 %) than the ISA index (160 %) compared to the direct response when using only LSS. Despite limited data, this exploratory study showed the potential of this novel broad phenotype based on pooled VOCs to improve genetic selection for reduced boar taint risk, although further validation in larger populations is required.