Effects of amylin on bone development and egg production in hens.

Amylin is a member of the calcitonin family of hormones cosecreted with insulin from the pancreatic beta-cells that can act as an osteoblast mitogen and as an inhibitor of bone resorption in mice and humans. The aim of this study was to investigate the role of amylin on bone formation and some egg parameters in hens. The study was performed in 60 hens aged 10 wk. Thirty hens constituting the treatment group were s.c. injected with amylin at a 75 microg/kg dose every other day. The remaining hens were used as the control group. Five birds from the treatment and control groups were slaughtered at 14, 16, 18, and 20 wk of age and serum and bone parameters were compared between the treatment and control groups. The remaining 20 hens were fed without any amylin injection until 35 wk. All hens at the end of the 35th week were slaughtered and then serum, bone, and egg parameters were assessed. In the treatment group, bone calcium levels increased, whereas serum calcium levels decreased. This dose of amylin also increased the cortical width of tibiotarsuses in hens. Eggshell thickness was found thicker in the treatment group than in the control group. Overall, the results of this study suggest that amylin may stimulate the bone and eggshell quality by increasing calcium uptake from the bloodstream and may influence the sustainability of yield in hens.