Combined effects of dietary starch:Protein ratios and short cycles of fasting/refeeding on Nile tilapia growth and liver health

This study evaluated the combined effects of different dietary starch:protein ratios (SPR) and short cycles of fasting/refeeding (FR) on Nile tilapia juveniles on growth, feed and nutrient use, whole-body composition and liver health. Three diets with SPR classified as high (S30:P32; 0.96 g:g), intermediate (S25:P36; 0.69 g:g) and low (S21:P39; 0.53 g:g) were fed to fish over 60 days on three feeding regimes: 0FR-fish fed daily (control treatment); 1 FR-fish fasted for one day and refed for three days and 2 FR-fish fasted for two days and refed for three days. Fish (2.25 +/- 0.01 g) were allotted to a completely randomized factorial design (3 x 3; n = 3). Fish growth and feed conversion ratio decreased (p < .05) with increasing FR. There was no significant difference in daily feed intake between regular-fed and fasted tilapia as a consequence of hyperphagia in fasted fish. Protein and energy productive values increased (p < .05) with increasing SPR. The occurrence of hepatic steatosis was similar (p > .05) among daily-fed fish regardless of SPR but increased (p < .05) with increasing SPR in fasted fish. Regardless of dietary SPR, short cycles of fasting/refeeding do not promote compensatory growth. Therefore, Nile tilapia around 2g should be fed daily with low-SPR diet.

Automated summary

This study evaluated the combined effects of different dietary starch:protein ratios (SPR) and short cycles of fasting/refeeding (FR) on Nile tilapia juveniles. The results showed that short cycles of fasting/refeeding do not promote compensatory growth in Nile tilapia. It is recommended to feed Nile tilapia around 2g daily with low-SPR diet.