Figure 5.

Assessment of the impacts of direct in vitro PFAS exposure on the ability of mouse spermatozoa to fertilize an oocyte and support early embryonic development. Cauda epididymal spermatozoa were incubated in a PFAS mixture (low or high dose) or control, for 3 h prior to being used for in vitro fertilization. (A) The percentage of fertilized oocytes (those with pronuclei formation and extrusion of the second polar body) was recorded as the percentage of the total number of oocytes collected per replicate. Oocytes were coincubated with spermatozoa from each treatment group in each of three biological replicates (equating to a total of 60, 70, and 53 oocytes being assessed from the control, low and high PFAS treatment groups, across all replicates, respectively). (B) The number of fertilized oocytes that reached the two-cell stage was also recorded as a transformed percentage of fertilized cells, (C) as was the number of fertilized oocytes that reached blastocyst stage. (D–G) Embryo development was then tracked for 96 h, and the development rate of each group is represented as a transformed percentage of the number of zygotes to each embryo stage at (D) 24, (E) 48, (F) 72, and (G) 96 h. Graphical data are presented as arcsine transformed data ± s.e.m. (n = 3 male mice/group). Differences between groups were assessed with either a one-way or two-way ANOVA, with Tukey's multiple comparison test. *P < 0.05,****P < 0.0001.