title: Changes in peripheral inhibin levels and follicular development following treatment of buffalo with PMSG and Neutra-PMSG for superovulation.
abstract: Fourteen buffalo were synchronized by administration of a prostaglandin (PG) salt Lutalyse in a double injection schedule, with a single intramuscular (im) injection of 25 mg at Day -13, followed by 30 mg and 20 mg im 12 h apart on Day 0 of the experiment. The 30-mg PG injection was designated as 0 h of the experiment. Group I animals (n = 4) received saline and served as the controls, while animals in Groups II and III (n = 5 each) received PMSG (2500 IU im at -48 h. Group III animals were administered 5 ml Neutra-PMSG intravenously at 60 h. Blood samples were collected every 48 h from Day -12 to Day -4, every 24 h from Day -4 to Day 0, every 3 h from Day 1 to Day 4 and every 24 h from Day 5 to Day 10 of experiment for the measurement of peripheral plasma inhibin concentrations by RIA. The number of large follicles (> 10 mm diameter) in animals of Groups II and III was assessed by ultrasonography on Days -2, -1, 0, 1, 2, 5 and 7 of the experiment. Treatment with PMSG of Group II animals resulted in a significant increase (P < 0.05) in plasma inhibin concentrations over that of control animals of Group I at 24 to 99 h, with a peak inhibin concentration of 1.01 +/- 0.31 ng/ml at 48 h. Treatment with Neutra-PMSG in Group III animals caused a significant reduction (P < 0.05) in the peripheral inhibin concentrations at 84 to 120 h and in the number of large unovulated follicles at 168 h compared with that in Group II animals. Peripheral inhibin levels in Group III animals came down to those of Group I after 21 h of Neutra-PMSG treatment. These results suggest that treatment of buffalo with PMSG for superovulation causes a marked rise in peripheral inhibin concentrations. Administration of Neutra-PMSG after PG treatment reduces the peripheral inhibin concentrations and the number of large unovulated follicles.
authors.affiliation: Embryo Biotechnology Centre National Dairy Research Institute, Karnal 132 001, India. NDRI@X400.NICGW.NIC.IN
authors.forename: P
authors.initials: P
authors.lastname: Palta
authors.forename: M
authors.initials: M
authors.lastname: Kumar
authors.forename: S
authors.initials: S
authors.lastname: Jailkhani
authors.forename: R S
authors.initials: RS
authors.lastname: Manik
authors.forename: M L
authors.initials: ML
authors.lastname: Madan