Lower light intensity reduces larval aggression in matrinxã, Brycon amazonicus

Light intensity affects the survival and growth of matrinxã larvae, Brycon amazonicus (Spix & Agassiz, 1829)

“…This response occurs in lower light intensity triggered by the release of chemicals such as melatonin, one that can modulate aggressive behaviour in fish (Oliveira & Gonçalves, ). This premise was confirmed by Lopes et al (), since under this condition the display of aggressive interaction was reduced among matrinxã larvae at 12 hr after hatching. Based on this, we assumed that with the reduction in the aggressive behaviour under low light intensity, the survival increases and the zootechnical parameters of animals subjected to the manipulation of this abiotic factor improve.…”

“…Ekström & Meissl, ; Falcón et al, ), reduce aggressiveness (e.g. Lopes et al, ) and increase survival in Brycon larvae.…”

“…The mean values of light intensity close to 20 lx (low), 200 lx (intermediate) and 2,000 (high) lx were selected according to Lopes et al (), because these levels modulate the frequency of aggressive behaviour exhibited by B. amazonicus larvae and, therefore, may have a significant effect on the survival and growth of these animals. Light intensities were obtained from the use of the spiral‐shaped white fluorescent lamp, as the light colour may affect the performance of fish larvae as reported by Karakatsouli et al () and Luchiari, Freire, Pirhonem, and Koskela, ().…”

“…In this context, several studies were carried out in an attempt to reduce cannibalism and to increase survival and zootechnical performance for matrinxã maintained in artificial systems. These included the use of different types and sizes of food (Atencio‐García, Zaniboni‐Filho, Pardocarrasco, & Arias‐Castellanos, ; Pedreira & Sipaúba‐Tavares, ), use of different densities, diets and tank formats (Saccol‐Pereira & Nuñer, ), thyroid hormones (Leonardo et al, ), probiotic supplementation (Dias et al, ) and tryptophan (Wolkers, Serra, Szawka, & Urbinati, ), different shape and colour of aquariums (Pedreira, Sipaúba‐Tavares, & Silva, ), maintenance of groups with individuals of differential sizes (Carvalho, Souza, Pinheiro‐da‐Silva, & Villacorta‐Correa, ), different stocking densities and water temperatures (Barros, Villacorta‐Correa, & Carvalho, ) and different levels of light intensity (Lopes, Villacorta‐Correa, & Carvalho, ). In fact, the manipulation of environmental factors in aquaculture is often used, and potentiate the production of species of commercial interest (e.g.…”

“…The luminosity, for example, is an essential environmental condition for the survival of fish (Rick & Bakker, ). Some studies suggest that the manipulation of light intensity can regulate biological rhythms and modulate various physiological functions in different species of fish, and it may reflect on survival (Mukai, Nai, & Lim, ; Navarro, Navarro, Murgas, & Felizardo, ), growth (Biswas, Morita, Yoshizaki, Maita, & Takeuchi, ; Falcón, Migaud, Muñoz‐Cueto, & Carrillo, ; Imsland et al, ; Rad, Bozaoglu, Gözükara, Karahan, & Kurt, ), food intake (Kitagawa et al, ; Puvanendran & Brown, ), metabolic rate (Porter, Duncan, Handeland, Stefansson, & Bromage, ), locomotor activity (Navarro et al, ; Trippel & Neil, ), body pigmentation, sexual maturation, reproduction (Fujii, Sugimoto, & Oshima, ; Song et al, ), melatonin (Ekström & Meissl, ; Falcón et al, ) and aggressive behaviour (Carvalho, Ha, & Gonçalves‐de‐Freitas, ; Carvalho, Mendonça, Costa‐Ferreira, & Gonçalves‐de‐Freitas, ; Lopes et al, ; Sarmento, Almeida, Marcon, & Carvalho, ).…”