Larvicultura de matrinxã em tanques de diferentes cores

Abstract

Resumo -O objetivo deste trabalho foi avaliar o efeito de diferentes cores de tanques na larvicultura de Brycon orthotaenia, durante os primeiros dez dias de criação. Foram avaliados tanques de cores claras (branco, azul claro e verde claro) e escuras (marrom e preto). Como alimento, utilizaram-se larvas de Prochilodus costatus, até o quinto dia de alimentação, e a partir do terceiro dia foi também fornecida ração comercial com 55% de proteína bruta. Foram analisados: o crescimento, a sobrevivência e o fator de condição de Fulton. Aos cinco dias, tanto o peso como o comprimento total e a taxa de crescimento específi co (TCE) foram semelhantes entre os tratamentos. No entanto, aos dez dias, animais mantidos em tanques de cores escuras apresentaram menor peso e comprimento total, porém, com TCE semelhante apesar das diferentes cores de tanque. O fator de condição de Fulton, ao fi nal do experimento, foi menor nos animais mantidos em tanques escuros. A sobrevivência foi menor em tanques de cor preta, aos cinco e dez dias de criação. Os maiores valores foram registrados nos tanques de cores marrom, verde claro e branco. Tanques claros são recomendados para a larvicultura de B. orthotaenia, pelo melhor desempenho e sobrevivência dos animais.Termos para indexação: Brycon orthotaenia, alimentação, canibalismo, manejo. Matrinxã larviculture in tanks of different colorsAbstract -The objective of this work was to evaluate the effect of different color tanks on Brycon orthotaenia larviculture, during the fi rst ten days of rearing. Light color tanks (white, light blue and light green) and dark tanks (brown and black) were evaluated. The fi shes were fed with Prochilodus costatus larvae until the 5 th day and, from the 3 rd day on, commercial dry feed with 55% crude protein was also supplied. The growth, survival and Fulton's condition factor were evaluated. At fi ve days of feed, the weight, total length and specifi c growth rate (SGR) were similar among treatments. However, after ten days, the animals kept in dark tanks showed the lowest weight and total length; but the SGR was similar despite the different color tanks. The Fulton's condition factor, observed at the end of the experiment, was lower in animals reared in dark tanks. The survival was lower in black tanks, at fi ve and ten days of rearing. The best survival, at the end of the experiment, was observed in brown, light green and white tanks. Light tanks are recommended for B. orthotaenia larviculture, for animals' best development and survival.

Larviculture of two neotropical species with different distributions in the water column in light- and dark-colored tanks

“…A similar result was observed by Pedreira et al (2008b) working with larvae of Brycon orthotaenia reared in light-colored tanks (white, light blue and light green). This is a species from the same basin as curimatá-pioa, and it is a neotropical characiform that swims in the water column.…”

“…On the other hand, pelagic species have eyes placed laterally (Kirchheim & Goulart, 2010). The contrast between the color of the food organism and the wall of the tank is important for the visual perception of the prey by the larvae (Krise & Meade, 1986;Ostrowsky, 1989), providing higher or lower visibility and consumption of prey (Pedreira & Sipaúba-Tavares, 2001;Strand et al, 2007), and also affecting survival (Tamazouzt et al, 2000;Pedreira et al, 2008b), growth (Jentoft et al, 2006;Strand et al, 2007;Monk et al, 2008), biochemical parameters (Karakatsouli et al, 2007), skin pigmentation (Amiya et al, 2005;Doolan et al, 2007), agonistic behavior and motor activity (Merighe et al, 2004), and finally productivity (Pedreira & Sipaúba-Tavares, 2001). …”

“…According to these authors, the higher survival rate occurred due to the better contrast between the tank color and the strong coloration of tropical freshwater plankton. Pedreira et al (2008b) recommended the larviculture of "matrinxã do São Francisco" (Brycon orthotaenia) in lightcolored tanks (white, light blue and light green), which provided better survival and growth. Tamazouzt et al (2000) observed that perch (Perca fluviatilis) reared in white and gray tanks, ingested more food items than in black tanks, with the growth rate being higher in white tanks than in black ones.…”

Combination of diet and water salinity in larviculture of piabanha-do-Pardo ( Brycon vonoi , Lima 2017)

“…These studies verified an improvement of animal development and decreasing of cannibalism by using forage larvae. Optimum results were also attained when matrinxã-doSão-Francisco larvae were fed curimatá-pioa (Prochilodus costatus) larvae (Pedreira et al, 2008b) when compared to matrinxã fed plankton (Pedreira et al, 2006) or piracanjuba larvae fed plankton or feeds (Pedreira, 2003).…”

“…Additionally, technology development in native Brazilian fish production has been a perceived need since the larval stage is a bottleneck for national large-scale fish farming. This is the case of the following fish species: piracanjuba (Brycon orbignyanus) (Pedreira, 2003), matrinxã (Brycon cephalus) (Pedreira et al, 2006), matrinxã-do-São-Francisco (Brycon orthotaenia) (Pedreira et al, 2008b) and piabanha-do-Pardo (B. vonoi), which become cannibals a few hours after hatching.…”