Veterinary and Comparative Biomedical Research

Veterinary and Comparative Biomedical Research

Evaluation of Newly Produced Equine Chorionic Gonadotropine (eCG/PMSG) with Effects on Immature Rat Ovaries: A Method Article

Articles in Press

Document Type : Original Article

Authors
Mohammad Javad Jahedi
Seyed Morteza Aghamiri
Mansooreh Miri Moghaddam
Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran
10.22103/VCBR.2026.26053.1101
Abstract
Equine Chorionic Gonadotropin (eCG), also known as Pregnant Mare Serum Gonadotropin (PMSG), is widely applied in reproductive biotechnology due to its dual follicle-stimulating hormone (FSH)- and luteinizing hormone (LH)-like activities and prolonged half-life. The classical rat ovarian weight bioassay remains one of the standard methods for assessing PMSG potency. This study aimed to compare the biological activity of PMSG preparations produced by Farnood Dam Kara (Iran) and Syntex (Argentina) in immature Wistar rats. Forty-nine immatures female Wistar rats (~50 g) were randomly assigned into six experimental groups, receiving PMSG at 10, 20, or 40 IU (Farnood or Syntex), and one control group receiving saline. A single subcutaneous injection was administered, and ovarian weights were measured 68 hours later. Both Farnood and Syntex PMSG significantly increased ovarian weight compared with controls (0.063 ± 0.006 g). A dose-dependent response was observed in treatment groups: Farnood increased ovarian weight from 0.090 ± 0.013 g (10 IU) to 0.139 ± 0.019 g (40 IU), while Syntex increased it from 0.087 ± 0.011 g (10 IU) to 0.135 ± 0.020 g (40 IU). Both preparations demonstrated comparable dose-dependent effects, confirming their potency. Newly manufactured PMSG (Farnood) may serve as a reliable and cost-effective alternative to imported formulations.
Keywords
Pregnant mare serum gonadotropin (PMSG)
Ovarian weight
bioassay
Gonadotropin potency
Reproductive biotechnology
Subjects
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Veterinary and Comparative Biomedical Research

Articles in Press, Accepted Manuscript
Available Online from 11 July 2026