Developmental increases in hypothalamic neuropeptide Y content with the embryonic age of meat- and layer-type chicks

We determined central neuropeptide Y (NPY) content of meat- and layer-type chicks at embryonic days 7, 14, 20, and at post-hatching day 1. The central NPY was detectable at day 7; hypothalamic NPY content developmentally increased with a similar pattern but a different level between both types of chicks. These results were discussed with respect to feeding behavior early period after hatching.