Changes in peripheral inhibin levels following PMSG treatment for superovulation in buffalo

Theriogenology

240

Exotic CHANGES

IN PERIPHERAL INHIBIN LEVELS FOLLOWING TREATMENT FOR SUPEROVULATION IN BUFFALO

PMSG

Palta, S. Jailkhani, M. Kumar and M.L. Madan Embryo Biotechnology Centre National Dairy Research Institute Karnal 132 001, India

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As inhibin is produced by the follicular granulosa cells the influence of FSH, the present study was undertaken to investigate the effect of PMSG treatment for superovulation on the peripheral inhibin levels in buffalo. Nine normal cycling Murrah buffaloes were synchronized for estrus by a prostaglandin double injection schedule (25 mg Lutalyse on Day 0 and 50 mg Lutalyse (Upjohn, Crawley, U.K.) in 2 doses of 30+20 mg, 12 h Group I animals (n=5) received a single apart on Day 13). injection of 2500 I.U. PMSG on Day 11 of the synchronized cycle while the control animals in Group II (n=4) were treated with Blood samples were collected daily from Day 1 to Day 32 saline. of experiment (21 days post PMSG treatment) and at 3 h intervals for 72 h between Day 14 and Day 17, at the time of expected Inhibin concentrations in plasma were measured by a estrus. double antibody RIA using a kit obtained from Dr. G. Bialy, NICHHD, NIH, MD, USA) and compared by ANOVA. under

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Mean peripheral plasma inhibin levels in buffaloes treated with PMSG for superovulation PMSG treatment on Day 11 of the synchronized cycle increased the peripheral inhibin levels significantly (PcO.01) over that in controls for a period of next 6 days. The highest mean inhibin level of 1.01 f 0.31 ng/ml was obtained 99 h after PMSG The inhibin levels were not significantly different treatment. between the controls and PMSG treated animals at any other phase These results indicate that treatment of buffalo of experiment. with PMSG for inducing superovulation results in a sustained elevation in plasma inhibin level which may be involved in suppression of endogenous FSH secretion. Figure

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