Effects of airport screening X-irradiation on bovine sperm chromatin integrity and embryo development.

"Biological samples, including cryopreserved sperm, are routinely X-rayed during air shipment. The goal was to investigate the impact of X-irradiation used for checked and carry-on luggage on bovine sperm chromatin integrity and postfertilization in vitro embryonic development. Frozen domestic bull sperm (Bos taurus) (n=9 bulls) stored in a dry shipper (-160 degrees C) was screened by X-irradiation 0, 1, 2, and 3 times as either carry-on or checked luggage. Duplicate straws were thawed, and sperm were assessed for chromatin damage using the sperm chromatin structure assay (SCSA) and by postfertilization in vitro developmental competence of mature oocytes... ...There were lower proportions of oocytes cleaved... and that developed to blastocysts... when fertilization was performed with sperm X-rayed 3 times using checked luggage irradiation; developmental competence (percentage cleaved embryos becoming blastocysts) was unaffected. There were no deleterious effects of other X-irradiation treatments on embryo development."