The Effect of CIDR Treatment in Estrus Synchronization on Insulin Like Growth Factor in Iraqi Ewes

The aim of study the ability of CIDR alone and in combination with PMSG in improving the fertility potential of the ewes and Determine the concentration of insulin like growth factors in blood of studied animals. Eighteen multiparous local Iraqi ewes aged between 3-4 years were randomly divided into three groups (n= 6/ group). Ewes were synchronized by CIDR The total number of animals used in the experiment was Eighteen ewes, The animals were subdivided into three groups; Group1 (n=6) ewes treated with CIDR for 12 day and treated with a single dose of intramuscular injection of PMSG 500 IU at the time of CIDR removal. Group 2 (n=6) non pregnant ewes treated only by CIDR, which applied by intra-vaginal route for (12 days), then withdrawal. Group3 (n=6 ) ewes control without treatment throughout the study. Regarding the insulin like growth factor (IGF-I), a significant upward increase in the level of the mentioned factor was observed as the study periods progressed in the treatment groups compared to the control group, which maintained similar levels of the studied factor in the different study periods. The period at lambing also recorded the highest level of the hormone under study, at a level of 21.61 ng/ml. A gradual significant (p˂0.05) increase was also observed with the progression of the study and pregnancy periods in the level of insulin like growth factor-1 in pregnant studied animals compared to those that did not become pregnant, which maintained close and almost constant levels despite the progression of the study periods. The period at the end of pregnancy and near birth (at lambing) also recorded the highest levels of the aforementioned factor at a level of 24.21 ng/ml. The results of the current study recorded a significant superiority (p˂0.05) in the weights of single births, males and females, compared to twins that gave births with lower weights, with significant superiority(p˂0.05) for single male births compared to those of single females. The treatment groups in the current study recorded a clear significant superiority (p˂0.01) in the pregnancy rate compared to the control group in which the pregnancy rate was 0%, in addition to the large difference, but not significant between the treatment groups themselves, as group G1 gave a much higher percentage compared to group G2, at 83% and 33% for the two treatment groups, respectively. The treatment groups showed a clear significant superiority in the lambing rate compared to the control group, in which the birth rate was 0%. The difference was also noted between the treatment groups themselves, as the G1 group recorded a lambing rate of 100%, which is higher than the lambing rate given by the G2 group, which did not exceed 33%.