The regulation of seasonal reproduction in sheep is intricately linked to the actions of melatonin, a hormone whose secretion varies with the photoperiod. Central to this process are the melatonin ...

On the Scottish archipelago of St. Kilda, the Soay sheep may not have any natural predators, but they do have the elements to contend with: a lack of food, brutal weather that can kill off half the ...

1. Fitness costs of reproduction are expected when resources are limited. Costs drive the evolution of life-history strategies and can affect population dynamics if females change their allocation of ...

This is a preview. Log in through your library . Abstract A central theme in life history theory is to determine how reproduction varies with age in iteroparous organisms. Evidence of ageing and ...

LITTLE ROCK (KATV) — Usually when we think of storms; clouds, thunder, lighting, and rain come to mind. Professors at the University of Arkansas at Monticello are calling the recent boom in sheep ...

Two papers selected for publication in the August 2007 issue of Biology of Reproduction demonstrate that adolescent female sheep that become pregnant before they have achieved their full growth may ...

A viral gene embedded in the sheep genome plays an essential role in the growth of the animal's placenta, according to a study of impregnated sheep. The result strengthens the case that similar viral ...