Effects of injection of PGF2α and eCG after CIDR removal on Reproductive Performance in Atabay ewes non-breeding season

Fourthy eaight Atabay ewes were randomly allocated as CRD in 4 treatment groups. Treatments were as (1) pretreatment with CIDR for 12 days and then receiving PGF2α at the time of withdrawal of the CIDR (2) pretreatment with CIDR for 12 days and then receiving eCG (3) pretreatment with CIDR for 7 days and then receiving PGF2α and (4) pretreatment with CIDR for 7 days and then receiving eCG. No significant differences were observed in term of male to female lambs ratio, lamb birth weight and weight after weaning (p>0.05). percentage of estrus were 100, 75, 58.33 and 50 respectively. The highest percentage of estrus were observed in treatment 1 with a significant difference with others (p<0.05). parturition rate was 88.33, 88.88, 100 and 100 percentages respectively and this term in treatment 3 and 4 were higher than treatment 1 significantly (p<0.05). lambing rate were 130, 100, 128 and 120 percentages respectively. Twining rate were 30, 0.0, 28 and 20 percentages respectively. The lowest Lambing and twining rates refer to treatment 2 with a significant differ with other treatments (p<0.05). In conclusion, long time CIDR (12 days) and injection of PGF2α had better results in comparison to eCG hormone and pretreatment with CIDR for 7 days had no significant difference between PGF2α or eCG injection. Also injection of eCG after CIDR removal (7 days) compare to (12 days) caused an increase in efficiency of parturition rate, lambing rate and twining rate in Atabay ewes.