Influence of tank color on somatic growth, body color and somatolactin response in Cichlasoma dimerus larvae

BERIOTTO, AGUSTINA C.; SALLEMI, JULIETA E.; DI YORIO, MARÍA P.; BRECCIA ANDRÉS; PÉREZ SIRKIN, DANIELA I.; VISSIO, PAULA G.

Mar del Plata

Congreso; Reunión conjunta SAIC SAB AAFE AACYTAL 2023. XXV Jornadas Anuales de la Sociedad Argentina de Biología (SAB).; 2023

SAIC SAB AAFE AACYTAL

Many studies indicate that certain species perform better in terms of growth, larval survival, stress levels, behavior, and body coloration, among other things, when kept in certain colored tanks. However,this variable has received little attention in most studies and is often not even reported. Therefore, the aim of this study was to examine how tank color affects somatic growth, body color, and the responseof somatolactin (SL), which is a pituitary hormone in fish that is linked to growth and skin pigmentation, in the larvae of Cichlasoma dimerus. Fish were reared for 90 days after hatching in white, lightblue or gray indoor tanks with two independent replicates. Somatic growth was estimated in terms of body weight and total length at the end of the study. Body weight was significantly higher (p < 0.02) in larvae reared in white tanks (147.8 ± 18. 6 mg) compared to those reared in light blue (84 ± 9.7 mg) or gray tanks (80.9 ± 9.7 mg). Larvae reared in white tanks showed a tendency toward larger sizes without any significant differences over those reared in light blue and gray tanks. Body color was evaluated by quantifying the number of head melanophores at 5, 12, and 25 days after hatching. In this case, no significant differences were observed among colors. To study SL response, the number of SL-immunoreactive cells was counted at 60 days after hatching, which tended to be higher in larvaereared in light blue and gray tanks than in white-reared larvae. In conclusion, the color of the rearing tank appeared to influence the somatic growth and SL production of C. dimerus, but not their body color for the days analyzed. These findings should be taken into consideration when designing the physical environment of C. dimerus rearing tanks.