Submitted to: Joint Abstracts of the American Dairy Science and Society of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 5/8/2000
Publication Date: N/A
Technical Abstract: Aliquots of neat semen from mature boars was diluted and stained with Hoechst 33342, incubated at 35 C and sorted at room temperature (SORT) into TEST-Yolk (20%) with out regard to separation of the X and Y sperm populations. Sorted samples were frozen in 3% glycerol and control semen in 11% lactose(UNSORT), respectively. Ovulation was controlled in 11 gilts by an altrenogest-PMSG-hCG regime. Gilts were laparotomized at 44 hr post-hCG and inseminated with 200,000 SORT or UNSORT into the isthmus of respective oviducts. Gilts were slaughtered and embryos recovered at 43 hr post insemination. The embryos were fixed in 4% paraformaldehyde, and stained with Texas Red-x phalloidin and Hoechst 33342. Confocal laser microscopy was used to visualize actin cytoskeleton and chromatin configuration. A total of 287 oocytes and embryos were evaluated. Cryopreservation and the subsequent thawing of the SORT sperm had a negative impact on fertilization nand embryo development compared to UNSORT sperm (at P level less than .05) as indicated by the incidence of sperm penetrated ova and total embryos (41.2 vs 96.5%), normal embryos without fragmentation or polyspermy (4.36 vs10.5/oviduct), incidence of normal embryos (55.4 vs 83.2%), and the proportion of 5-9 cell embryos of normal embryos (2.7 vs 21.4%); polyspermy (9.7%) and fragmentation (12.1%) were not different. These results demonstrate the combined negative impact of flow cytometric sorting and the sperm freezing and thawing process on fertilization rate and embryo development in the pig.