Influence of carrot, Daucus carota powder on growth performance and survival rates of Oreochromis niloticus fry

Abstract

Improving the growth, resistance and survival of Nile tilapia (O. niloticus) in aquaculture has important role in optimizing the production and profits. Carrot (Daucus carota) is a potential local nutraceutical that has antioxidative and immunostimulant properties. This study was performed to investigate the influence of carrot powder added in fish feed on the growth, survival rate and food conversion ratio of O. niloticus. A 90-day experiment was conducted on Nile tilapia of an average body weight and standard length of 0.5±0.02g and 3.5 0±0.5 cm respectively. The experiment was conducted in 70 litre plastic bowls with a water volume of 40 litre and 20 fish per bowl were given five treatments in three replications. Different carrot powder proportions of 0%, 6.15%, 9.23%, 12.3% and 15.38% were administered. Growth performances and water quality variables were measured using standard procedure. The highest final weight of 5.04±0.05g was obtained at 15.38% inclusion of carrot powder. Similarly, the highest mean weight gain (MWG) of 4.56±0.12g was recorded at T5 (15.38% inclusion of carrot powder), while the least MWG (3.57±0.05g) was obtained at T1 (0% inclusion of carrot powder). Significantly higher (p<0.05) specific growth rate (2.33±0.03%/day), protein efficiency ratio (0.95±0.01) and the best food conversion ratio (3.00±0.03) were recorded in fish treated with 15.38% inclusion of carrot powder. Survival rate of 95.6±0.00% was recorded at 0% and 6.15% inclusion levels of carrot powder, while there was 100% survival at 9.23%, 12.3% and 15.38% carrot powder inclusion levels. The levels of water temperature, pH, dissolved oxygen and ammonia were maintained within the ranges of 25.32±0.58°C to 25.87±1.54°C, 6.34±0.71 to 6.54±0.76, 5.21±0.48mg/l to 5.88±0.65mg/l and 0.04mg/l respectively. The results showed that carrot powder had significant effect on mean weight gain, specific growth rate, food conversion ratio and protein efficiency ratio of O. niloticus