Vol. 6, Issue 4 (2017)

Author(s):
K Murali Mohan

Abstract:
The present study was aimed to determine the progesterone profiles in ewes synchronization with CIDR. The ewes were synchronized with Controlled Internal Drug Releasing (CIDR) device containing 300 mg of progesterone. A total of 120 postpartum, parous, healthy ewes aged about 2 to 5 years were divided into 5 groups and each group consists of 24 animals. Each group was further subdivided into 2 groups consists of 12 animals and were studied during breeding and nonbreeding seasons. Group I ewes were considered as untreated control. Ewes in Group II were treated with CIDR and were left in place for 12 days followed by intramuscular injection of 400 IU of PMSG at the time of device removal. Ewes in Group III were treated with CIDR and 600 IU of PMSG was given intramuscularly at the time of removal of CIDR. Ewes in Group IV were treated as in Group II and additionally supplementation 200 IU of hCG injection at the time of mating. Ewes in Group V were treated as in Group III and additional injection of 200 IU of hCG at the time of mating. Plasma progesterone concentrations of experimental ewes were measured by enzyme-linked immunosorbant assay (ELISA). The progesterone levels before insertion were 1.44±0.13 ng/ml and 2.46±0.11, 3.63±0.10 and 5.11±0.16 ng/ml on day 3, 6 and 9 of treatment, respectively in breeding season. In nonbreeding season, the progesterone levels were 0.84±0.11 ng/ml before insertion of CIDR. During treatment, the progesterone levels were 1.84±0.14 ng/ml on day 3, 2.33±0.15 ng/ml on day 6, 3.01 ±0.18 ng/ml on day 9 and 2.55±0.10 ng/ml on day 12 of treatment (at the time of removal). The progesterone levels were significantly (P<0.01) increased from day 0 to day 9 of treatment and thereafter it was significantly (P<0.01) decreased on day 12 of treatment. Significantly, higher progesterone levels were recorded in all groups of ewes inserted with CIDR (3.62±0.21 to 2.99±0.10 ng/ml) compared to control group of ewes (1.43±0.07 ng/ml).