sheep Digital Vision

Scientists link biological response of sheep seasonality

Melatonin controls production of two different proteins in the pituitary gland that, depending on season, influence sex hormone-producing cells and fertility.

Many species of animals have developed seasonal fertility patterns so that their offspring are born when there is most access to food sources. For example, most breeds of sheep are most fertile in the fall so that lambs are born in the spring when ewes can graze on fresh grass.

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