Estimation of Additive and Non-Additive Genetic Variances of Body Weight, Egg Weight and Egg Production for Quails (Coturnix coturnix japonica) with an Animal Model Analysis

Abstract

This study estimates the additive and non-additive variances for egg production and body weight traits of two lines of quails from a long-term selection with the help of the REML method. For the body weight of 42-day-old females (BW42f) and males (BW42m), a total of 7,934 records for line 1 and 7,214 records for line 2 from 21 generations were used in our analyses. Additionally, 1,717 records of females from line 1 and 1,671 records of females from line 2 contained information on their egg production at an age of 42 to 200 days (EN200), on the average egg weight for the first 11 weeks of their laying season (EW1), on the average egg weight from weeks 12 to 23 (EW2), and on their body weight at an age of 200 days (BW200f). A multivariate additive animal model and one-trait dominance models, which include the inbreeding coefficients as covariates, were fitted to the data. The estimates of the heritability gained from our dominance models were smaller than those from the additive model. For line 1, the heritability values decreased for EN200 from 0.35 to 0.32, for EW1 from 0.66 to 0.56, for BW200f from 0.42 to 0.38, and for BW200m from 0.51 to 0.49, respectively. For the first line, the respective ratio (d 2 ) of the dominance variance to the phenotypic variance for EN200, EW1, BW200f and BW200m was 0.08, 0.22, 0.09 and 0.21, and the values for the second line were 0.12, 0.06, 0.001 and 0.23.

Egg shell quality in Japanese quail: characteristics, heritabilities and genetic and phenotypic relationships

“…The average egg weight in this study was 12.76 g (Table 1), which was lower than the 13.40 g reported by Khaldari et al (2010) and 13.25 g reported by Copur et al (2010). On the other hand, this average value for EW is in agreement with those reported by Erensayin and Camci (2002), Sahin et al (2002), Roshdy et al (2010) and Lotfi et al (2012) of between 12.00 and 12.75 and also higher than the 10.27-11.43 g reported by Hassan et al (2003), Kul and Seker (2004), Mielenz et al (2006), Sezer (2007), Alkan et al (2010) and Al-Daraji et al (2010) for quails. Specific gravity (SG) measures the relative proportion of shell of the egg based on its density (Wolc et al, 2010).…”

Genetic characterization of egg weight, egg production and age at first egg in quails

“…Minvielle (1998), in a review about genetic improvement in quails, found genetic correlation for egg production and egg weight ranging from -0.55 to -0.19. Mielenz et al (2004) when studying two quail lines, observed values for genetic correlation between total egg production and egg weight of -0.36 and 0.07 in lines 1 and 2, respectively. Paiva (2004), using the same genetic material, found estimates of genetic correlation between age at first egg and egg weight at 60 and 90 days, respectively, of 0.04 and -0.36 for the yellow line; -0.32 and -0.09 for the blue line; and -0.01 and -0.19 for the red line.…”

“…quails for production, presented heritability values indicated by the collected data from 0.32 to 0.39 for egg production and from 0.35 to 0.62 for egg weight. More recently, Mielenz et al (2004) used two lines of Japanese quails -the first selected for high body weight and low egg weight and the second selected only for high egg weight -and found heritability for egg production and egg weight of 0.35 and 0.66 for the first line and 0.21 and 0.58 for the second line, respectively. Paiva (2004), using the same lines of quails studied in the present work, found heritability values of 0.73; 0.13; and 0.17 for the yellow line; 0.19; 0.15; and 0.19 for the blue line; and 0.22; 0.25; and 0.15 for the red line for age at first egg, egg weight at 60 and 90 days, respectively.…”

Interação genótipo X ambiente em codornas de postura alimentadas com rações com dois níveis de energia metabolizável

“…Tabela 2 -Herdabilidades e correlações genéticas para peso do ovo, altura de albúmen, espessura da casca e produção total de ovos nos ambientes 1 e 2 em três linhagens de codornas de postura estimativas de herdabilidade encontradas são diferentes das reportadas na literatura, cujos valores estão entre 0,21 e 0,39 (Minvielle, 1998;Mielenz et al, 2004). A linhagem 3 foi a que apresentou maior variabilidade para produção de ovos, que foi mais evidente no ambiente 2, ou seja, em condições de restrição energética, há maior diferenciação genética entre as aves, o que possibilita a seleção.…”

“…Os valores de herdabilidade da linhagem 3 e alguns valores da linhagem 2 são maiores que os encontrados na literatura, em torno de 0,42 a 0,74 (Minvielle, 1998;Mielenz et al, 2004). No entanto, as linhagens 1 e 2 praticamente se enquadram nessas estimativas.…”