Role of Leptin in Japanese Quail Development

Abstract

Maaajova M., D. Lamo‰ova, M. Zeman: Role of Leptin in Japanese Quail Development. Acta Vet Brno 2002, 71: 473-479. Leptin, a hormone produced mainly by adipose tissue, controls energy balance and can also influence the embryonic development and growth. In our study we investigated the effects of leptin administration during the embryonic development on hatching rate, posthatching growth and development of Japanese quail (Coturnix japonica). At embryonic day 5, 0.1 µg or 1 µg of recombinant mice leptin in 50 µl of phosphate buffered saline was injected into the albumen of incubating eggs. Birds from each group were weighed daily and killed by decapitation at day 0, 2, 5, 7, 14, 21, 28, 35, 42, 49 and 56 of postembryonic life. Plasma concentrations of triiodothyronine (T3), testosterone and total lipids in plasma and in the liver were measured. Quail treated with leptin hatched earlier and expressed a higher body weight during the whole experimental period than the control group (p < 0.05). Significant changes in T3 concentrations, total lipids and body weight were seen immediately after hatching and shortly before sexual maturity. Testosterone levels and eggs laying were higher in leptin groups in comparison to controls. We suppose that the endocrine milieu of the developing avian embryo is influenced by leptin and the administration of this hormone during embryonic life can accelerate embryonic development of birds. birds, embryogenesis, growth, reproduction, triiodothyronine, testosterone, total lipids