Men also have a biological clock

VALENCIA, Spain, Jan. 21 (UPI) -- Mammalian males can reproduce until late in life, but their children may have more abnormalities, researchers in Spain said.

Although mammalian males can reproduce until late in life, evidence of hazards to offspring has emerged in human and animal models, the researchers said.

Silvia Garcia-Palomares of the University of Valencia in Spain and colleagues said that their study, published in the Biology of Reproduction, provides clear, well-controlled data of deleterious effects on the offspring of aged male mice mated to females of prime reproductive age.

The offspring from the elderly males exhibit abnormalities not only in several behavioral traits, but also in reproductive fitness and longevity -- the offspring fathered by old mice had a shorter life span.

Moreover, mating the offspring from aged males resulted in the production of pups exhibiting decreased weights at weaning when compared with pups from the offspring of younger males.

Garcia-Palomares said the defects causing these abnormalities in offspring are unknown and should be the objective of intriguing studies in the future.