Ovarian Biometry, Oocyte Yield and Oocyte Quality of Baladi Goats as Affected by Ovarian Status in Breeding and Non-Breeding Season

Abstract

The current study was undertaken to elucidate the effect of ovarian status in breeding and non-breeding season on the ovarian biometry, oocyte yield and oocyte quality of Baladi goats. Ovaries were collected by slicing from slaughter houses and classified with or without CLs during breeding (September-December) and non-breeding (March-July) seasons. Ovaries were weighed and measured, while oocytes were recoverded, yielded and categorized with or without CLs in breeding or non-breeding seasons. Results showed that ovarian weight and biometry (length, width and thickness) were higher in breeding than in non-breeding season, but the differences were significantly only for width. Number of follicles and oocytes/ovary (P<0.001) as well as number/ovary and proportion of oocytes at compact (P<0.0001) and denuded (P<0.05) stage were higher in breeding season than in non-breeding one. Number of degenerated oocytes/ovary was not affected significantly by season, but its proportion was lower (P<0.001) in breeding than in non-breading season. Number/ovary and proportion of partial denuded oocytes and proportion of denuded oocyte were not affected significantly by breeding season. Weight and biometry of ovaries was higher on ovaries bearing CL (CL+) than in non-bearing ones (CL-). Only ovarian width was higher (P<0.001) by 38% in CL+ than in CL- group. Ovaries bearing CL had higher (P<0.05) total follicles and oocyte yield/ovary (P<0.01) as well as oocyte recovery rate (P<0.05) than CL- ovaries. Number of compact, denuded and partial denuded oocytes/ovary was not affected by CL bearing. Number of compact oocytes tended to be greater on ovaries without than with CL. Number of degenerated oocytes/ovary was higher (P<0.05) on CL+ ovaries. Proportion of all oocyte categories was not affected by bearing CL. Finally, the effect of interaction between breeding season and bearing CL on all parameters studied was not significant.  In conclusion, the goat ovaries without CL in breeding season yielded better  oocyte quality than in non-breeding season, in term of COCs proportion. During non-breeding season, goats oocytes were available to be harvested from slaughtered goat does with acceptable yield and quality.