Culture of bovine morulae in media supplemented with immunoglobulins

Bovine morulae (d 6; n = 257) were obtained to evaluate the effect of Ig on embryo development in vitro to the hatched blastocyst stage or until degeneration. Embryos were cultured in Ham's F-10 containing either 6.4 mg/ml steer serum, .64 mg/ml bovine gamma globulins, bovine IgG, bovine IgM alone, and steer serum added to gamma globulins, IgG, or IgM. In steer serum alone, 69.6% of the embryos developed to the expanded blastocyst stage, whereas 73.9% of embryos in gamma globulin and steer serum and 25% of embryos in gamma globulin alone reached the same stage of development. None of the morulae cultured in IgG and IgM alone or IgG and IgM with steer serum reached the expanded blastocyst stage. Additionally, the times to degeneration were shorter when embryos were cultured in IgG (54.9 h) and IgM (59.4 h) plus steer serum than for embryos placed in gamma globulin plus steer serum (77.6 h) or steer serum (81.5 h) alone. These results suggest that .64 mg/ml bovine gamma globulin did not affect embryo growth, whereas .64 mg/ml IgG and IgM were toxic to early development of bovine embryos in vitro.