Effect of Winter Feeding Frequency on Growth Performance, Biochemical Blood Parameters, Oxidative Stress, and Appetite-Related Genes in Takifugu Rubripes

Abstract

We evaluated the effect of winter feeding frequencies (F1: one daily meal; F2: two daily meals; F3: four daily meals; F4: continuous diurnal feeding using a belt feeder) on the growth performance, biochemical blood parameters, oxidative stress, and appetite-related genes in Takifugu rubripes held at a constant temperature (18.0 ± 1.0°C) for 60 days. The results showed that the final weight, weight gain rate, specific growth rate, and survival of tiger puffer in the F3 group showed the best growth performance. The total cholesterol, triglyceride, and glucose levels were significantly higher with the increased feeding frequency. We also observed the antioxidant enzymes (superoxide dismutase, catalase, glutathione, and glutathione peroxidase) and the digestive enzyme activities (trypsin, amylase, and lipase) in tiger puffers cultured in the F1 group were significantly higher than those in the F3 and F4 groups. In addition, the tiger puffers in the F1 group exhibited the highest expression of orexin and the lowest contents of glucose, tachykinin, cholecystokinin, and leptin among all the groups. In contrast, the mRNA levels of tachykinin, cholecystokinin, and leptin in the tiger puffers in the F4 group may be attributed to the negative feedback mechanism in the brain-hypothalamus-neuropeptide axis. All parameters exhibited relatively optimal levels in the F3 group. In conclusion, inappropriate feeding frequencies could have negative effects on growth and physiological indicators. The optimal feeding frequency for enhanced growth performance while maintaining a relatively good physical condition in juveniles of this species was four times a day.