Growth and Development: Regulatory Mechanisms in Growth and Development

A strategy that improves growth efficiency is to reduce basal metabolic rate, providing additional energy for growth. Thyroid hormones enhance metabolism and lipolysis. Previous studies have shown that increase of feeding frequency could change blood hormonal profile affecting metabolism and growth in some animals. The objective of this study was to investigate the effect of increased feeding frequency on thyroid hormones status in turkey. Twenty turkey chickens were randomly assigned to 2 groups. In control group, turkey chickens were fed ad libitum, whereas birds in treatment group fed every 4 h and blood samples were collected at 4 intervals. Data were analyzed with Proc Mixed of SAS. Overall mean plasma concentration of triiodothyronine in treated group was higher than control (4.05 ± 0.34 vs. 2.59 ± 0.30 ng/mL, P = 0.0001). Mean plasma concentration of thyroxin in treated group was higher than control (47.50 ± 1.6 vs. 24.08 ± 1.7 μg/dL, P = 0.0001). It was concluded that increasing feeding frequency failed to decrease thyroid hormones level. As a result, this kind of feeding management may not be efficient to improve growth performance in turkey chicken.