Association between ACTA1 candidate gene and performance, organs and carcass traits in broilers

Abstract

This study investigates the genetic association of the SNP present in the ACTA1 gene with performance traits, organs and carcass of broilers to help marker-assisted selection of a paternal broiler line (TT) from EMBRAPA Swine and Poultry, Brazil. Genetic and phenotypic data of 1,400 broilers for 68 traits related to body performance, organ weights, weight of carcass parts, and yields as a percentage of organs and carcass parts were used. The maximum likelihood method, considering 4 analytical models, was used to analyze the genetic association between the SNP and these important economic traits. The association analysis was performed using a mixed animal model including the random effect of the animal (polygenic), and the fixed effects of sex (2 levels), hatch (5 levels) and SNP (3 levels), besides the random error. The traits significantly associated (P<0.05) with the SNP were analyzed, along with body weight at 42 days of age (BW42), by the restricted maximum likelihood method using the multi-trait animal model to estimate genetic parameters. The analysis included the residual and additive genetic random effects and the sex-hatch fixed effect. The additive effects of the SNP were associated with breast meat (BMY), liver yield (LIVY), body weight at 35 days of age (BW35); drumstick skin (DSW), drumstick (DW) and breast (BW) weights. The heritability estimates for these traits, in addition to BW42, ranged from 0.24±0.06 to 0.45±0.08 for LIVY and BW35, respectively. The genetic correlation ranged from 0.02±0.18 for LIVY and BMY to 0.97±0.01 for BW35 and BW42. Based on the results of this study, it can be concluded that ACTA1 gene is associated with performance traits BW35, LIV and BMY, DW, BW and DW adjusted for body weight at 42 days of age. Therefore, the ACTA1 gene is an important molecular marker that could be used together with others already described to increase the economically important traits in broilers.

Identification of selection signatures involved in performance traits in a paternal broiler line

“…Besides identifying regions in the chicken genome under selection pressure, knowing the genes annotated in these regions and how they biologically act is essential for understanding how the selection signatures contributed to the current phenotype of the evaluated animals. Since TT broiler line is under multi-trait selection since 1992 aiming to improve body weight, feed conversion, cut yields, breast weight, viability, fertility, and hatchability and to reduce abdominal fat [17, 23], it is expected that genes influencing the performance of these traits are under selection pressure.…”

“…Chickens used in this study were from a broiler line developed by the Embrapa Swine and Poultry National Research Center. This line, called TT, was originated from Cornish and White Plymouth Rock breeds, that has been under a multi-trait selection process focused on body weight, feed conversion, cut yields, breast weight, abdominal fat, and other traits, since 1992 [17, 23, 24]. The chickens were raised in open sided poultry houses, receiving commercial broiler diet and water ad libitum [17, 24].…”

“…Embrapa Swine and Poultry, a Brazilian National Research Center, has been raising experimental chicken populations under selection since the 1970’s. One of these lines is the paternal broiler line called TT, which has been under multi-trait selection since 1992 [23]. Identification of selection signatures in chicken lines can help understand which regions underwent selection pressure over time and how their biological mechanisms act to express the traits of interest, such as muscle growth and fat deposition.…”

Genome-wide association study reveals novel loci associated with body size and carcass yields in Pekin ducks

“…Three genes, TBC1D1 (encoding TBC1 domain family member 1), BAAT (bile acid-CoA: amino acid N-acyltransferase), and PHLPP1 (PH domain and Leucine-rich repeat protein phosphatase 1) were highlighted as functionally plausible candidate genes for pig growth and fatness traits [5, 6]. In addition to pigs and cattle, similar studies have been conducted in poultry, and numerous candidate genes associated with carcass traits have been found in chickens, including TBC1D1 , LCORL (ligand-dependent nuclear receptor corepressor-like), LAP3 (leucine aminopeptidase 3), LDB2 (LIM-domain-binding 2), and TAPT1 (transmembrane anterior posterior transformation 1) [7–10]. However, compared with other domestic animals, study about the genetic basis of growth traits in ducks is lacking.…”

Association of RUNX2 and TNFSF11 genes with production traits in a paternal broiler line

“…Fornari et al (2014) found that the SNP g.9144C>G in the TNFRSF11B (osteoprotegerin) gene was associated with skeletal structure, performance, and carcass traits in the TT Reference Population of broilers. Genetic associations were also found between the ACTA1 (actin, alpha1, skeletal muscle) gene and performance and carcass traits in the same population (Venturini et al, 2015).…”