Veterinary and Comparative Biomedical Research

Veterinary and Comparative Biomedical Research

Effects of Ghrelin on Macronutrient Selection and Food Intake Patterns in Neonatal Broiler Chicks

Articles in Press

Document Type : Original Article

Authors
Mehran Pourmashayekhi 1
Hossein Jonaidi 1
Iman Zadsar 1
Hirouki Kaiya 2
1 Department of Basic Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran
2 Department of Biochemistry, National Cerebral and Cardiovascular Center Research Institute, 16 5-7-1 Fujishirodai Suita, Osaka, Japan
10.22103/vcbr.2025.25067.1077
Abstract
Ghrelin, a hormone recognized for its role in stimulating appetite in mammals, exhibits distinct effects in birds, particularly concerning fat storage and appetite suppression. This study aimed to investigate the impact of ghrelin on macronutrient selection in neonatal chicks, addressing a gap in knowledge regarding non-mammalian species. In the first trial, four nearly isocaloric diets—normal, high carbohydrate, high protein, and high fat—were formulated, and eight-day-old chicks received intracerebroventricular (ICV) injections of chicken ghrelin to evaluate its effect on macronutrient intake. In the second trial, birds were given unrestricted access to all macronutrients simultaneously. In the third trial, chicks were raised on one macronutrient diet and subsequently switched to another. The results indicated that ghrelin significantly reduced intake across all diets, with notable variations based on diet type. Specifically, it decreased protein consumption while increasing the carbohydrate-to-protein intake ratio. This suggests that ghrelin may play a crucial role in energy management, particularly during activities such as flying, where energy demands increase while food availability may be limited. Consequently, low protein intake may lead to a preference for carbohydrates due to the influence of ghrelin. These findings enhance our understanding of avian feeding behavior and energy regulation, underscoring the necessity for further research on the implications of ghrelin for nutritional strategies in non-mammalian species.
Keywords
Ghrelin
Intracerebroventricular injection
Macronutrient selection
Neonatal chicks
Subjects
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Veterinary and Comparative Biomedical Research

Articles in Press, Accepted Manuscript
Available Online from 17 November 2025