1Department of Physiology, Sri Venkateswara Veterinary University, Tirupati-517 502, Andhra Pradesh, India
2Department of Animal Genetics and Breeding, Sri Venkateswara Veterinary University, Tirupati-517 502, Andhra Pradesh, India
3Department of Veterinary Surgery and Radiology, Sri Venkateswara Veterinary University, Tirupati-517 502, Andhra Pradesh, India
*Corresponding Author: Srinivasa Prasad Chigurupati, Department of Veterinary Physiology, Sri Venkateswara Veterinary University, Tirupati-517 502, Andhra Pradesh, India, Email: spchigurupati@rediffmail.com
Online published on 13 August, 2024.
In in vitro culture systems IGF-I was known to promote follicular maturation, granulosa cell proliferation and increase overall cellular function. The expression patterns of developmentally important markers for IGF-I are expressed differentially during the transition of preantral follicles to the ovulatory stage. Therefore, we aimed to investigate the influence of time specific addition of Insulin like growth factor-I (IGF-I) on in vitro development of sheep preantral follicles (PFs’).
Mechanically isolated sheep preantral follicles were cultured for six days either in TCM 199B or standard medium supplemented with IGF-I at different points during the culture period and were subsequently subjected to in vitro maturation (IVM) for additional 24 hrs to evaluate different follicular development parameters.
Based on the results, it is concluded that: 1) IGF-I supplementation was needed during early rather than later stages of culture period, therefore, role of IGF-I in time/stage specific manner in cultured preantral follicles is confirmed. 2) Supplementation of TCM 199B with IGF-I simultaneously for the first two days followed by TCM 199B alone without any growth factor (s) in later days (Treatment 1) supported better development of PFs’ in vitro.
IGF-I, In vitro culture, Preantral follicles, Sheep
