Estimation of genetic parameters and response to selection for eighth week body weight in Kuttanad ducks (Anas platyrhynchos domesticus)

Cyriac, S., Joseph, L., Anitha, P., Antony, S. and Vineetha, P.G. 2020. Estimation of genetic parameters and response to selection for eighth week body weight in Kuttanad ducks (Anasplatyrhynchos domesticus). Indian Journal of Poultry Science, 55(1): 11–15.

A selection experiment was conducted at University Poultry Farm, Mannuthy, Kerala to estimate the genetic parameters and to study the response to selection for eighth week body weight in Kuttanad ducks. One thousand and eighty-eight day-old Kuttanad ducklings procured from progressive farmers of Kerala formed the base generation (S₀). Based on body weight at eighth week, top ranking 150 females and 25 males were selected through individual selection method. From the 25 sire families, 979, 969 and 1610 ducklings were produced by artificial insemination in S₁, S₂ and S₃ generation in pedigreed hatches. Body weight was recorded at 8, 10 and 12 weeks of age in each generation. Genetic parameters for body weight at 8, 10 and 12 weeks were estimated using full sib correlation method. Selection differential and response to selection were calculated for body weight at 8 weeks. The body weight was significantly (P°0.05) higher in S₃ generation at 8, 10 and 12 weeks of age. The heritability estimates for body weight at 8 weeks of age based on sire plus dam components (h²s+d) were 0.251, 0.313 and 0.243 in S₁, S₂ and S₃ generations. High values were observed for phenotypic correlation between body weight at 8 and 10, 8 and 12, and 10 and 12 weeks of age. The genetic correlations were higher than the environmental correlations except in the sire component in S₁ generation. The expected response in S₂ and S₃ generation was 79.63 g and 66.61 g, respectively but the observed response was -24.43 g, 82.28 g and 212.66 g in S₁, S₂ and S₃ generations. The regression coefficients indicate that higher increase in body weight per generation was obtained for body weight at 8 weeks (94 g) rather than for body weight at 10 (56 g) and 12 weeks (55 g).