The effect of vitamins <em>C</em> and <em>E</em> on diet of nile tilapia larvae's (<em>Oreochromis niloticus</em> L.), on the octo parasite occurrence, survival, weight and length, during sexual reversion process

Abstract

The effect of the vitamin C and vitamin E in the diet was evaluated on the ectoparasite occurrence, survival, weight and length in Nile tilapia larvae, Oreochromis niloticus L. (Perciformes, Cichlidae), during sexual reversion. Larvae with medium weight of 0,01 g and 10 mm of total length were submitted to four treatments: T1 = without addition of vitamins, T2 = 1000 mg of vitamin C, T3 = 300 mg of vitamin E and T4 = 1000 mg of vitamin C and 300 mg of vitamin E per kg of treat. In the beginning, the occurrence of diagnosed ectoparasite was of 100% (90,0% Trichodina and 10,0% mixed infection). At the end of the experiment a significant decrease of Trichodina occurrence in the treatment with vitamin E (T3) in relation to the treatment without vitamin (T1) was met. Weight, total and standard length also had a significant increase of the treatment with vitamin E (T3) in relation to the others. For survival the best result was in treatments with vitamin C (T2). It is concluded then that vitamin C supplementation in the treat was beneficial compared to survival and that vitamin E was effective on the parameters related to the corporal development (weigh and length), as well as on the occurrence of Trichodinas in Nile tilapia larvae, during the sex reversion process.