There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Four replicate experiments were conducted to determine the effects of pinealectomy
and environmental lighting on testes and comb weights in the broiler cockerel. Birds
were housed in brooder batteries under a 14L:10D fluorescent white light regime for
2 weeks and then allotted to light-controlled chambers. Surgery was performed when
the chicks were 3 to 5 days old. The fluorescent light treatments were 14L:10D green
(narrow-band, 545 nm peak), 14L:10D cool white, and constant darkness. At the end
of the 46-day experimental period, testes weights were determined and comb weight
recorded. Pinealectomy did not affect testes weights or comb development. Darkness
significantly (P less than .05) depressed testes and comb weight. This suggests that
lack of light, but not pinealectomy, affects circulating hormone levels and/or tissue
responsiveness in the young cockerel.