Resumen de FR 17. Production and transfer of frozen bovine embryos from criollo limonero catlle

Romualdo Gonzalez, J. C. Velarde, S. Zambrano, P. Esté

• The venezuelan criollo limonero cattle came originally from the hispanic bovine breeds brought to America during the colonial times. This breed is characterized for its great adaptation to the extreme warm tropical conditions, high fertility and milk production. The largest population of this breed is located in the north-western region of Maracaibo Lake on the Limon and Guasare river banks in the Mara county of Zulia state. An official program (CORFONLUZ)* of multiovulation and embryo transfer (MOET) is being conducted with the objetives of increasing their genetic value. Up to now a total of 253 (60.5 %) transferable embryos have been produced from which 222 (87.7 %) were frozen to build a genetic bank. From 70 thawed and evaluated embryos 60 (85.7 %) were considered good to be transfered to crossbred (Cebu x dairy breeds) recipients. From the first 37 embryos transfered, 18 (48.6 %) resulted in pregnancy and the rest are waiting for pregnancy diagnosis. This preliminary pregnancy rate (48.6 %) is considered satisfactory and clearly shows the advantage of these embryo cryopreservation technologies to warrant the genetic future of this breed considered a venezuelan patrimony.