Influence of environmental color on zootechnical performance and feeding behavior during masculinization of Nile tilapia
Perila Maciel Rebouças, Rafael dos Santos Rocha, Meirelane Chagas da Silva, José Antônio Delfino Barbosa Filho, Wladimir Ronald Lobo Farias, Cássia Roseane Silveira Pinto, Josenilde de Castro Henrique
The rise of tilapia in Brazil and the world increasingly needs the best growing conditions. Despite the Nile tilapia has diurnal, your vision is considered a strong sensory stimulus, and as the perception of the color contrast of medium, production losses may be evidence due to stress caused too. Thus, an experiment was conducted at Biotechnology Aquaculture Applied Center (CEBIAQUA), The Fishing Engineering Department, Federal University of Ceará, with the aim of evaluating the influence of the background color translucent on zootechnical performance and feeding behavior of Nile tilapia during masculinization. We used 200 post-larvae (average weight = 0:02 ± 0.01g; mean initial length = 1.10 ± 0.01 cm) of Nile tilapia, packed in 40 L aquarium, covered with cellophane, for 28 days. Fish were distributed in a completely randomized in two treatments (blue and green) and five replications. Environmental variables analyzed were dissolved oxygen, temperature, pH and photoperiod and productive performance was evaluated weight, total length, condition factor and lot uniformity. Behavioral observations occurred twice daily, immediately before the first feeding and 2 minutes after each feeding treatment. We found no significant difference in water parameters in two treatments. The weight, length and condition factor did not differ between treatments. There was a higher survival rate, more lot uniformity, and an obvious grouped behavior during feeding in aquaria translucent greens than blues. So for the masculinization of Nile tilapia, it is recommended to translucent green, because the results were most satisfactory.