Inbreeding effects on average daily gains and Kleiber ratios in Guilan province sheep

The objective of the present study was to evaluate the effects of inbreeding on growth traits in Guilan province sheep. Traits included average daily gain from birth to 3 months (ADG1), average daily gain from birth to 6 months (ADG2), average daily gain from 3 months to 6 months (ADG3) and corresponding Kleiber ratios (KR1, KR2 and KR3, respectively). Data and pedigree information used in this study were collected during 1994 to 2011 by the Agriculture Organization of Guilan Province. The effects of inbreeding rate on the traits investigated (for a change of 1% in inbreeding) were analyzed using the Reg procedure of SAS for type of birth, lamb’s sex and all lambs. The effects of inbreeding on all traits except ADG1 were positive. The regression coefficients of ADG1, ADG2 and KR2 were estimated to be -0.138, 0.101 and 0.0053 g, respectively (P