Prenatal diagnosis of sex in cattle by amniocentesis.

A method for the aspiration of amniotic fluid from pregnant cows at 70 to 1000 day gestation and the subsequent cultivation of amniotic cells in vitro is described. The unit for aspirating amniotic fluid includes a sterile Plexitron tubing fitted with a 60 ml syringe on one end and a 12 in needle ("18 gauge) partially encased in a 6 inch AI pipette on the other. Aspiration of fluid is accomplished through the vaginal route by piercing the dorsal fornix and chromosome analysis is performed on amniotic cells after cultivation in vitro for four to seven days. This method, which is simple and accurate, provides a safe diagnostic procedure for the prenatal detection of sex and cytogenetic defects in cattle.