Nowadays, many boar reproduction researches are directed to improve extenders and to increase cold shock
protection of semen. Little research is focused on the influence of egg yolk combined with alternative cold shock
protective media. Egg yolk could interfere with other compounds present in the extender composition. The influence
of egg yolk addition was assessed in boar sperm cells, cooled at 5ºC, to elucidate its effect on motility and membrane
integrity. Flow Cytometry and Computer Assisted Semen Analysis (CASA) were used to determine the rate of sperm
with intact plasma and acrosomal membrane, respectively the sperm cells motility. Statistical analyses (T-Test) were
performed using GraphPad Prism version 5.00. Androhep Plus supplemented with 20% egg yolk (AhPlus+20%EY)
indicated a higher cold shock protection in progressive motility (93.9±2.64%) and membrane integrity
(79.78±4.14%), rather than the extender without egg yolk (p