Quantifying the effect of inbreeding on average daily gain and Kleiber ratio in Mazandaran native chickens

AbstractThe aims of this study was to evaluate inbreeding effects for growth rate (average daily gain from hatch to 8  weeks of age (ADG1–8), average daily gain from hatch to 12 weeks of age (ADG1–12), average daily gain from 8 weeks of age to 12 weeks (ADG8–12), average daily gain from hatch to sex maturity (ADG1-SM), average daily gain from 8 weeks of age to sex maturity (ADG8-SM), average daily gain f rom 12 weeks to sex maturity (ADG12-SM), and Kleiber ratios (KR1–8, KR1–12, KR8–12) in Mazandaran native chickens. The data set of 82,446 pedigreed individuals over 21 generations was analyzed. All individuals were grouped into three classes based on the inbreeding coefficient: First class co ntained non-inbred birds (F = 0) and second and third classes contained inbred individuals (0 <  F ≤ 5% andF >  5%, respectively). The effects of inbreeding coefficient on the studied traits were estimated by the restricted maximum likelihood method (REML) applying the WOMBAT software and fitting individual increase in inbreeding coefficient (ΔFi) of birds as linear covariates under 6 different animal mod els. ADG8-SM and ADG12-SM increased non-significantly by 0.003 and 0.005 g, respectively, due to 1% increase in ΔFi, while ADG1–8, ADG1–12, ADG8–12, ADG1-SM, KR1–8, and KR1–12 decreased (P <  0.001), respectively, by 0.012 g, 0.011 g, 0.010 g, 0.014 g, 0.003 g, and 0.002 g. Also, KR8–12 non-significantly decreased by ...
Source: Tropical Animal Health and Production - Category: Veterinary Research Source Type: research