The Effects of Different Leveles of Tomato Powder on Growth and Survival Rates and Carotenoids Deposition in Skin and Muscle Tissues of Silver Dollar Fish(Metynnis hypsauchen)

Inroduction & In this study, investigated effects of carotenoid, equivalent to natural lycopene in different leveles of tomato powder on growth and survival rates as well as carotenoids deposition of silver dollar fish (Metynnis hypsauchen).
Material and Fishes were fed with 5 different diets and were reared in three replicates for each treatment (15 experimental units) in a completely randomized design for 8 weeks. the five experimental diets included a negative control without any pigment material and positive control containing 20 mg/kg of synthetic astaxanthin and three dietary treatments respectively including 15, 20 and 25 mg/kg of total carotenoid, equivalent to natural lycopene. The total length and total weight was measured to investigate the status of fish growth and in order to measure the accumulation of carotenoids in the skin and muscle, was used from spectrophotometry.
The length, weight, gain weight, condition factor and Special growth factor of treatments especially in entire experimental period were lower related to negative and positive control treatments. The amount of carotenoids in the skin and muscle tissues of fish in all treatments was observed higher than the negative control. In experimental treatments with increasing concentration of natural carotenoid in the diets had increased the carotenoid skin and muscle tissues (p≤0.05).
Counclusion: Low performance between different indexes of growth in experimental treatments, represents presence of limiting factors of growth, the high fiber and low fat Content in tomato powder experimental treatments. Reducing the storage of carotenoids in comparison with the positive control treatment and increasing its storage compared to non-pigmented treatment in experimental treatments indicates inadequate and ineffective metabolism of carotenes in tomato powder in silver dollar fish.