Edwin C. Atabay | Eufrocina P. Atabay | Rodante V. De Vera | Flocerfida P. Aquino | Felomino V. Mamuad | Libertado C. Cruz
Discipline: Biology, Veterinary Medicine, Animal Science
The present study was conducted to determine the possibility of producing buffalo clone embryos after nuclear transfer using oocytes from ovaries stored at low temperatures. Buffalo ovaries were collected using physiological saline solution at temperatures of 10, 15 or 32ºC during transport from slaughterhouse to the laboratory. Aspiration of oocytes from ovaries stored at 10 and 15ºC was done at 20-24 hr post collection (hpc). Cumulus-oocyte complexes retrieved were matured in vitro for 22-23 hr and were subjected to nuclear transfer. Likewise, oocytes from ovaries collected at 32ºC were aspirated immediately upon arrival (4-6 hpc), matured in vitro, and subjected to nuclear transfer to serve as control. The reconstructed embryos were cultured in vitro and assessed for embryonic development. The results indicate that the rates of maturation, enucleation, fusion, cleavage, and blastocyst formation did not differ significantly (P<0.05) between low temperatures groups (10 and 15ºC) and these results were comparable to that of the control group wherein the ovaries were stored at 32ºC during transport. In sum, the results suggest that buffalo ovaries can be held at temperature ranging from 10 to 15ºC for up to 24 hr without compromising developmental competence of the retrieved oocytes. The present work demonstrated for the first time that the oocytes retrieved from buffalo ovaries stored at low temperatures were viable and pre-implantation embryos were successfully produced after nuclear transfer.