Genetic and phenotypic correlations between performance traits with meat quality and carcass characteristics in commercial crossbred pigs

Genetic correlations between performance traits with meat quality and carcass traits were estimated on 6,408 commercial crossbred pigs with performance traits recorded in production systems with 2,100 of them having meat quality and carcass measurements. Significant fixed effects (company, sex and batch), covariates (birth weight, cold carcass weight, and age), random effects (additive, litter and maternal) were fitted in the statistical models. A series of pairwise bivariate analyses were implemented in ASREML to estimate heritability, phenotypic, and genetic correlations between performance traits (n = 9) with meat quality (n = 25) and carcass (n = 19) traits. The animals had a pedigree compromised of 9,439 animals over 15 generations. Performance traits had low-to-moderate heritabilities (6SE), ranged from 0.0760.13 to 0.4560.07 for weaning weight, and ultrasound backfat depth, respectively. Genetic correlations between performance and carcass traits were moderate to high. The results indicate that: (a) selection for birth weight may increase drip loss, lightness of longissimus dorsi, and gluteus medius muscles but may reduce fat depth; (b) selection for nursery weight can be valuable for increasing both quantity and quality traits; (c) selection for increased daily gain may increase the carcass weight and most of the primal cuts. These findings suggest that deterioration of pork quality may have occurred over many generations through the selection for less backfat thickness, and feed efficiency, but selection for growth had no adverse effects on pork quality. Low-to-moderate heritabilities for performance traits indicate that they could be improved using traditional selection or genomic selection. The estimated genetic parameters for performance, carcass and meat quality traits may be incorporated into the breeding programs that emphasize product quality in these Canadian swine populations

Estimates of phenotypic correlations and their standard error of estimates between carcass and performance traits.

1<p><b>BW</b> = Birth weight (kg); <b>WNW</b> = Weaning weigh (kg); <b>NURW</b> = Nursery weight (kg); <b>ENDW</b> = End weight (kg); <b>ADG</b> = Average daily gain (g/d); <b>UFD</b> = Ultrasound backfat depth (mm); <b>ULD</b> = Ultrasound loin depth (mm); <b>UIMF</b> = Ultrasound IMF; <b>FCR</b> = Feed conversion ratio; <b>HCW = </b>Hot carcass weight (kg); <b>CCW = </b>Cold carcass weight (kg); <b>FD = </b>Backfat depth (mm); <b>LD = </b>Loin depth (mm); <b>CLEN = </b>Carcass length (cm); <b>LEA = </b><i>Longissimus dorsi</i> muscle area (cm²); <b>TEXS = </b>Texture score; <b>CMAR = </b>Carcass marbling score; <b>USW = </b>Untrimmed side weight (kg); <b>UHAM = </b>Untrimmed ham weight (kg); <b>ULOIN = </b>Untrimmed loin weight (kg); <b>USH = </b>Untrimmed shoulder weight (kg); <b>UBEL = </b>Untrimmed belly weight (kg); <b>THAM = </b>Trimmed ham weight (kg); <b>TLOIN = </b>Trimmed loin weight (kg); <b>TBEL = </b>Trimmed belly weight (kg); <b>PICN = </b>Trimmed picnic shoulder weight (kg); <b>BUTT = </b>Butt shoulder weight (kg); <b>RIBS = </b>Ribs weight (kg).</p>2<p>The significant correlations are bolded (<i>P<0.05</i>).</p><p>Estimates of phenotypic correlations and their standard error of estimates between carcass and performance traits.</p

Descriptive statistics for performance traits: number of animals per trait (n), means, SD, minimum (Min.) and maximum (Max.) values.

<p>Descriptive statistics for performance traits: number of animals per trait (n), means, SD, minimum (Min.) and maximum (Max.) values.</p

Significance of the fixed and random effects included in the models for the analysis of Performance Traits.

<p>**<i>P<0.05</i>; * <i>P<0.1</i>; NS: Non-significant.</p>1<p>Birth weight.</p><p>Significance of the fixed and random effects included in the models for the analysis of Performance Traits.</p

Estimates of genetic (below diagonal), phenotypic (above diagonal) correlations, heritabilities (diagonal) and their standard error of estimates among performance traits.

1<p><b>BW</b> = Birth weight (kg); <b>WNW</b> = Weaning weigh (kg); <b>NURW</b> = Nursery weight (kg); <b>ENDW</b> = End weight (kg); <b>ADG</b> = Average daily gain (g/d); <b>UFD</b> = Ultrasound backfat depth (mm); <b>ULD</b> = Ultrasound loin depth (mm); <b>UIMF</b> = Ultrasound IMF; <b>FCR</b> = Feed conversion ratio.</p>2<p>The significant correlations are bolded (P<0.05).</p><p>Estimates of genetic (below diagonal), phenotypic (above diagonal) correlations, heritabilities (diagonal) and their standard error of estimates among performance traits.</p

Estimates of phenotypic correlations and their standard error of estimates between meat quality and performance traits.

1<p><b>BW</b> = Birth weight (kg); <b>WNW</b> = Weaning weigh (kg); <b>NURW</b> = Nursery weight (kg); <b>ADG</b> = Average daily gain (g/d); <b>UFD</b> = Ultrasound backfat depth (mm); <b>ULD</b> = Ultrasound loin depth (mm); <b>UIMF</b> = Ultrasound IMF; <b>FCR</b> = Feed conversion ratio; <b>WLW</b> = Whole loin weight (kg); <b>REAW</b> = Rib eye weight (kg); <b>BFW</b> = Backfat thickness weight (kg); <b>RTW</b> = Rib trim weight (kg); <b>BOW</b> = Bone/Neural weight (kg); <b>CL</b> = Cooking loss (%); <b>REAL</b> = Minolta L* rib eye area; <b>REAA</b> = Minolta a* rib eye area; <b>REAB</b> = Minolta b* rib eye area; <b>SHF</b> = Shear force (newton); <b>LOINL</b> = Minolta L* loin; <b>LOINA</b> = Minolta a* loin; <b>LOINB</b> = Minolta b* loin; <b>PHU</b> = pH ultimate; <b>HGML</b> = Minolta L* ham <i>gluteus medius</i>; <b>HGMA</b> = Minolta a* ham <i>gluteus medius</i>; <b>HGMB</b> = Minolta b* ham <i>gluteus medius</i>; <b>HQFL</b> = Minolta L* ham <i>quadriceps femoris</i>; <b>HQFA</b> = Minolta a* ham <i>quadriceps femoris</i>; <b>HQFB</b> = Minolta b* ham <i>quadriceps femoris</i>; <b>HILL</b> = Minolta L* ham <i>iliopsoas</i>; <b>HILA</b> = Minolta a* ham <i>iliopsoas</i>; <b>HILB</b> = Minolta b* ham <i>iliopsoas</i>; <b>DL</b> = Drip loss (%).</p>2<p> The significant correlations are bolded (<i>P<0.05</i>).</p><p>Estimates of phenotypic correlations and their standard error of estimates between meat quality and performance traits.</p

Estimates of genetic correlations and their standard error of estimates between meat quality and performance traits.

1<p>See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110105#pone-0110105-t006" target="_blank">Table 6</a> for trait abbreviation definitions.</p>2<p> The significant correlations are bolded (<i>P<0.05</i>).</p><p>Estimates of genetic correlations and their standard error of estimates between meat quality and performance traits.</p