Efficiency of different selection strategies against boar taint in pigs

Abstract

The breeding scheme of a Swiss sire line was modeled to compare different target traits and information sources for selection against boar taint. The impact of selection against boar taint on production traits was assessed for different economic weights of boar taint compounds. Genetic gain and breeding costs were evaluated using ZPlan+, a software based on selection index theory, gene flow method and economic modeling. Scenario I reflected the currently practiced breeding strategy as a reference scenario without selection against boar taint. Scenario II incorporated selection against the chemical compounds of boar taint, androstenone (AND), skatole (SKA) and indole (IND) with economic weights of -2.74, -1.69 and -0.99 Euro per unit of the log transformed trait, respectively. As information sources, biopsy-based performance testing of live boars (BPT) was compared with genomic selection (GS) and a combination of both. Scenario III included selection against the subjectively assessed human nose score (HNS) of boar taint. Information sources were either station testing of full and half sibs of the selection candidate or GS against HNS of boar taint compounds. In scenario I, annual genetic gain of log-transformed AND (SKA; IND) was 0.06 (0.09; 0.02) Euro, which was because of favorable genetic correlations with lean meat percentage and meat surface. In scenario II, genetic gain increased to 0.28 (0.20; 0.09) Euro per year when conducting BPT. Compared with BPT, genetic gain was smaller with GS. A combination of BPT and GS only marginally increased annual genetic gain, whereas variable costs per selection candidate augmented from 230 Euro (BPT) to 330 Euro (GS) or 380 Euro (both). The potential of GS was found to be higher when selecting against HNS, which has a low heritability. Annual genetic gain from GS was higher than from station testing of 4 full sibs and 76 half sibs with one or two measurements. The most effective strategy to reduce HNS was selecting against chemical compounds by conducting BPT. Because of heritabilities higher than 0.45 for AND, SKA and IND and high genetic correlations to HNS, the (correlated) response in units of the trait could be increased by 62% compared with scenario III with GS and even by 79% compared with scenario III, with station testing of siblings with two measurements. Increasing the economic weights of boar taint compounds amplified negative effects on average daily gain, drip loss and intramuscular fat percentage.

Genome-wide association analyses for boar taint components and testicular traits revealed regions having pleiotropic effects

“…However, the risk of tainted meat has to be controlled and the percentages of tainted carcasses have to be reduced. Beside adapted housing systems and feeding regimes, reduction of tainted boars can be achieved by selection strategies within breeding programs [ 3 , 4 ].…”

Odeurs indésirables de la viande de porcs mâles non castrés : problèmes et solutions potentielles

“…Cependant, l'alternative mise en oeuvre actuellement est d'évaluer le risque à l'abattoir chez les collatéraux par le nez humain (Mathur et al, 2013) car cela permet de travailler sur de grands effectifs. Par ailleurs, il est possible d'utiliser l'information génomique pour prédire les teneurs en composés odorants dans le tissu gras (Haberland et al, 2014 ;de Campos et al, 2015 ;Lukić et al, 2015).…”

Olfactory evaluation of boar taint: effect of factors measured at slaughter and link with boar taint compounds

“…Few recommendations have been made about how farmers can reduce the prevalence of boar taint. Selection against boar taint is a promising route to reduce AND concentrations but this path is associated with negative effects on fertility, daily gain, drip loss and intramuscular fat (Moe et al, 2009;Haberland et al, 2014). Previous research has indicated that boar taint prevalence may vary from farm to farm .…”