Assessment of Bos taurus embryos comparing stereoscopic microscopy and transmission electron microscopy

Abstract

has proved inaccurate with the latter method. Embryos were collected from Holstein heifers 7 days after artificial insemination and classified according to the criteria established by the International Embryo Transfer Society (IETS). Ten embryos were sorted in each quality group (good, fair, and poor), processed and fine sections obtained for evaluation under electron microscope. Results showed that embryos classified as good using stereoscopic microscopy increased from 33 to 47% when evaluated by transmission electronic microscopy, while the fair embryos decreased from 33 to 20% and the poor embryos did not change. Likewise, using the Kappa Cohen’s test the rate of correlation between the evaluation methods this was found to be moderate. These findings show that the greatest variation between the two methods used is within the embryos classified as fair. In conclusion, the classification criteria for