Feeding frequency has a determinant role in growth performance, skeletal deformities, and body composition in the Mexican pike silverside (Chirostoma estor), an agastric short-intestine fish (Teleostei: Atheriniformes)

Abstract

Several fish species with potential for aquaculture diversification possess agastric short-intestine anatomical configuration. The absence of a stomach or long intestine in fish may imply specific feeding frequency strategies for optimal growth. Because adequate feeding frequencies are paramount for thriving fish culture, the present study aimed to evaluate the effects of feeding frequency on growth performance, feeding efficiency, survival, deformities, proximate body composition, and muscle growth in Mexican pike silverside (Chirostoma estor: Atherinopsidae) a short-intestine agastric fish. Fish with an average weight of 180.57 ± 3.02 mg were randomly distributed in twelve tanks and fed four (M4), eight (M8), and twelve (M12) times a day until apparent satiety for 45 days. Significantly higher growth (70%) was found in M12 treatment compared to M4. There was no difference in survival among treatments. However, significantly fewer deformities were found in the M12 treatment compared to M8 and M4 treatments. Increased feeding frequency produced fish with higher lipids, with a concomitant reduction in ash content. Muscle fiber diameters were significantly different in all treatments: M12 (32.97 ± 3.13 μm), M8 (30.28 ± 4.59 μm), and M4 (26.74 ± 4. 42 μm). These results reflect the importance of feeding strategies in accordance to fish habits and their digestive configurations and may be relevant for other emerging species with similar digestive morphology and lower in the trophic chain, which are essential for aquaculture diversification and sustainability.