Associations between pedigree, meat quality, and meat quantity of slaughterhouse donor cows and oocyte recovery, embryo development, and pregnancy after embryo transfer

Abstract

The aim of this study was to examine associations between pedigree and meat quality and quantity of slaughterhouse donor cows and oocyte recovery, embryo development, and pregnancy after embryo transfer. Ovaries of individual Korean native cows were obtained from a slaughterhouse. The ear tag numbers were obtained and pedigree, meat quantity (Grades A, B, and C), and meat quality (Grades 1++, 1+, 1, 2, and 3) of the donors were compared 24h after slaughter. No significant differences were found in the average number of oocytes recovered from cows with differing pedigrees. More oocytes were recovered from cows in the Grade A and Grades 1++, 1+, and 2 groups than from the other groups. The blastocyst development rate was significantly lower in the four pedigree groups than in the control group. However, pedigree had no significant effect on development rates to the 2-cell, 8-cell, or blastocyst stages. Embryo development rates to the 2-cell and 8-cell stages were significantly higher in the Grade 3 and control groups than in the Grades 1++, 1+, and 1 groups; furthermore, the development rate to the blastocyst stage was significantly higher in the Grades 2 and 3 groups than in the other meat quality groups. Pregnancy rate was not significantly associated with pedigree, meat quantity, or meat quality. These results may facilitate the selection of donors for in vitro production with desirable characteristics for improving meat quality or quantity, providing an economically beneficial approach for improving genetic resources in beef cattle.