Feeding entrainment of locomotor activity rhythms, digestive enzymes and neuroendocrine factors in goldfish

Citation

Vera L, De Pedro N, Gomez-Milan E, Delgado MJ, Sanchez-Muros MJ, Madrid JA & Sanchez-Vazquez FJ (2007) Feeding entrainment of locomotor activity rhythms, digestive enzymes and neuroendocrine factors in goldfish. Physiology and Behavior, 90 (2-3), pp. 518-524. https://doi.org/10.1016/j.physbeh.2006.10.017

Abstract
The existence of food anticipatory activity (FAA) in animals subjected to daily feeding schedules seems to be mediated by a feeding-entrainable oscillator (FEO). Such an FEO may help in anticipating meal time and so optimizing food acquisition and nutrient utilization. In this study we investigated the existence of FAA and whether digestive enzymes, plasma cortisol, hypothalamic NPY and gastrointestinal tract (GIT) and plasma melatonin were entrained by periodic feeding in goldfish. We observed that periodically fed goldfish showed FAA in locomotor activity as well as in amylase and NPY. Alkaline protease and GIT melatonin were higher after feeding, whereas plasma cortisol levels were reduced. Plasma melatonin remained unmodified before and after meal time. These results suggested that scheduled feeding entrained both behavioral and certain physiological patterns in goldfish, FAA being of adaptive value to anticipate a meal and prepare the digestive physiology of fish.

Keywords
goldfish; FEO; locomotor activity; amylase; protease; NPY; cortisol; melatonin

Journal
Physiology and Behavior: Volume 90, Issue 2-3