Enhanced in vitro developmental competence of sheep embryos following sericin supplementation of the in vitro maturation and in vitro culture media

•Study of adding Sericin in sheep in vitro embryo production has been performed for the first time.•Sericin has the potential to successfully replace blood serum derivatives in culture media.•Results showed that supplementation of sericin in IVM and IVC steps significantly improves the blastocyst production which make promising to enter industrial step.

The objective was to determine the effects of various sericin concentrations (0, 0.1, 0.5, 1, and 2.5%) during in vitro oocyte maturation (IVM) and in vitro embryo culture (IVC) on ovine embryo development. Pubertal Sanjabi ewes’ oocytes were aspirated from slaughterhouse derived ovaries and matured in vitro. Semen was collected from a healthy fertile ram, capacitated and the in vitro matured oocytes were fertilized using capacitated spermatozoa. The IVM and IVC media were supplemented with 0, 0.1, 0.5, 1 and 2.5% of sericin. Addition of 0.5% of sericin during IVM and IVC significantly increased cleavage and blastocyst rates (85.48 ± 1.57 and 50.07 ± 3.04, respectively) compared with 0 and 0.1% of sericin. However, a too high concentration (2.5%) of sericin during IVM and IVC decreased cleavage and blastocyst rates compared with low concentrations (P < 0.05). In conclusion, appropriate concentrations (0.1 and 0.5%) of sericin promoted ovine blastocyst formation in vitro, although a high concentration of sericin suppressed embryo development.