Feeding Behaviour and Food Utilisation in Tilapia, Oreochromis Niloticus: Effect of Sex Ratio and Relationship With the Endocrine Status

• Published in: Physiology & behavior Vol. 62; no. 2; pp. 273 - 279
• Main Authors: Toguyeni, Aboubacar, Fauconneau, Benoit, Boujard, Thierry, Fostier, Alexis, Kuhn, Eduard R, Mol, Koen A, Baroiller, Jean-François
• Format: Journal Article
• Language: English
• Published: Cambridge Elsevier Inc 01-08-1997; New York, NY Elsevier
• Subjects: Animal Feed; Animals; Behavioral psychophysiology; Biological and medical sciences; Body Composition - physiology; Eating - physiology; Endocrine Glands - physiology; Feeding Behavior - physiology; Feeding behaviour; Female; Fundamental and applied biological sciences. Psychology; Growth - physiology; Hormones - blood; Hormones and behavior; Human health and pathology; Life Sciences; Male; Nutritional Status - physiology; Oreochromis niloticus; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Self-feeders; Sex Characteristics; Sex Ratio; Social Behavior; Thyroid and steroid hormones; Tilapia; Tilapia - physiology; Tissues and Organs; Sex ratio; Tilapia; Oreochromis niloticus; Self-feeders; Thyroid and steroid hormones; Feeding behaviour; Feeding behavior; Androgen; Growth; Estrogen; Sex; 17β-Estradiol; Metabolism; Ovarian hormone; Feeding; Testosterone; Vertebrata; Food intake; Pisces; Thyroid hormone; Triiodothyronine; Testicular hormone; Sex steroid hormone; EFFICACITE ALIMENTAIRE; ALIMENTATION DES POISSONS; HORMONE STEROIDIQUE
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/S0031-9384(97)00114-5

Toguyeni, A., B. Fauconneau, T. Boujard, A. Fostier, E. R. Kuhn, K. A. Mol and J. F. Baroiller. Feeding behaviour and food utilisation in Tilapia, Orechromis niloticus: Effects of sex ratio and relationship with the endocrine status. Physiol Behav 62(2) 273–279, 1997.—The feeding behaviour of male monosex, female monosex, and mixed groups of
Oreochromis niloticus was studied under conditions of self-feeding. Feeding activity was observed almost exclusively during the light period. The food intake pattern was similar whatever the sex ratio, and voluntary food intake (VFI) appeared lower in the male monosex groups than in the others. Male monosex groups displayed higher specific growth rates (SGR) and a lower food conversion ratio than female monosex and mixed groups. The SGR of males was higher in the monosex than in the mixed groups, whereas females of mixed and monosex groups displayed no significant difference in SGR. The efficiency of food utilisation was also analysed: nutrient retention ratios were higher in male monosex than in female monosex and mixed groups. Males displayed a distinctly higher metabolic capacity. Differences in sex-related hormones (11 ketotestosterone = 11-KT, 17
β-Oestradiol = 17
β-
E2) and a metabolic hormone (triiodothyronine = T3) were observed between males and females. The hypothesis of an involvement of these hormones in the higher metabolic capacity of males is discussed. The observed differences in feeding behaviour between the different groups also suggest an effect of social interactions on the efficiency of food conversion and thus on the differential growth of males and females.