Effect of aging on male reproduction in zebrafish (Danio rerio).

The study was designed to test the hypothesis that male aging is associated with a change in reproductive function in the zebrafish. Young (290 ± 37 d) and older (911 ± 48 d) males were combined with females (604 ± 24 d) to test the effect of male age on the number and fertility of eggs laid by their mates. 48% of breeding trials with young males and 25% of the trails with older males resulted in egg deposition.