Abstract:
This study evaluated the effect of breed and follicular status of Boer and indigenous goats on response to
superovulation and embryo yield. The oestrous cycles were synchronized with progestagen for nine days
and superovulated with porcine follicle-stimulating hormone. Does were cervically inseminated and
embryos were surgically flushed on day six following artificial insemination. The oestrous activity,
ovarian response, embryo yield and quality, did not differ significantly between breeds. The number
and size of follicles at the onset of superovulation treatment and during oestrus did not differ
significantly between breeds. The follicles 2–3 mm, 4–5 mm and total number of follicles at the onset
of superovulation treatment were positively correlated with the number of structures, embryos and
transferrable embryos recovered. The number of medium follicles (4−5 mm) at the beginning of
superovulation treatment increased the number of transferable embryos. The total number of follicles
>6 mm at the onset of superovulation was positively correlated to the number of unfertilized ova.
Although limited number of animals was used, the results suggest that breed has limited effect on
superovulation response. Instead, the quality and yield of embryos are dependent on number and size
of follicles present at the beginning of a superovulation treatment.
