Body condition status at mating affects gestation length, offspring yield and return rate in ewes

摘要: Abstract. The present study was planned to determine the effect of ewe body condition score (BCS) and parities on fertility, return rate, gestation length, fecundity, litter size lamb birth weight. Data were collected from 284 heads ewes with first fifth parity raised at a state farm for three consecutive (2002–2004) years. Teaser rams used monitor estrus twice daily in morning evening from September to October. BCSs body weights (BWs) recorded mating postpartum. The ewes, time breeding season within 6 h after the expulsion fetal membranes, divided into four groups basis of their BCS: thin (BCS  = ≤  2.0; n=70 ; 38), medium (BCS   2.5–3.0; n=122 142), fat  3.5–4.0; n=72 59) and very ≥  4.5; n=  20;17). BWs at postpartum highly correlated weight ( R=0.486 , P  0.01, R=0.130 ,  0.05, respectively). of ewes postpartum had positive effects weight ( Y=3.43 ±  0.10  +  0.130   0.047 ewe score (EBCS),  0.01; Y=  2.92   0.42   0.018   0.009 weight (EBW),  0.05 kg weight per BCS kilogram live weight, fertility rate, litter fecundity higher medium than thin and very χ2=  10.607,  0.01). BW affected gestation length positively  0.05). Return rate or number coitus for conception  0.05) groups. data revealed that ewes with  2.5–4.0) scores were profitable.