Optimal background colour for rearing Asian seabass (Lates calcarifer)

Abstract

Background colour influences the growth performance and feed utilization of various fish species. In the current study, the effects of different aquarium backgrounds (transparent, white, black, red, green and blue) on growth performance, feed utilization, digestive enzyme activities, flesh quality, carcass composition and haematological parameters were investigated in Asian seabass (Lates calcarifer). The fish (16.17 ± 0.02 g initial body weight) were distributed into eighteen glass aquaria (6 treatments × 3 replications) with the various background colours and reared for 10 weeks. At the end of the experiment, positive growth performance and feed utilization were observed in fish reared against transparent, white, black or green backgrounds, while negative effects were noted for fish reared on the remaining treatments (p < .05). Modulation of the main digestive enzymes was observed across the six treatments, indicating different strategies for utilizing nutrients by the fish. The activity ratio of trypsin to chymotrypsin was highest in the fish reared against a black background, followed by a white background. Flesh quality, in terms of protein synthesis capacity and protein turnover rate, indicated a significant improvement in the fish reared against white, black and green backgrounds, while the contents of myosin and actin were similar across the six colour treatments. Carcass composition and haematological parameters showed no negative effects in either of the preferred treatments. These findings indicate that the most suitable background colours for rearing Asian seabass are black, followed by white and green, while transparent, red or blue backgrounds are unsuitable.

Effect of tank colour on growth, survival, stress level, digestive enzymatic activities and body composition of snubnose pompano ( Trachinotus blochii Lacépède) larvae

“…Although the larvae grown in white and yellow tanks in the present study showed elevated cortisol levels, they had the highest total length and survival, respectively. Similar observation was noted in Asian seabass ( Lates calcarifer ) reared in white, black and green tanks in which the fish had higher total length and survival rates despite expressing elevated cortisol levels (Santisathitkul et al, 2020). These results show that the effect of cortisol on behavioural aspects affecting growth may be dose specific.…”

“…In the current study, we observed that crude protein, lipid, ash and moisture contents of larvae reared in tanks of different colours were significantly different. Similar results were observed in white seabream ( Diplodus sargus L.) grown in white, light blue and black tanks (Karakatsouli et al, 2007) and Asian seabass ( Lates calcarifer ) (Santisathitkul et al, 2020). However, contradictory results were observed in scaled carp ( Cyprinus carpio L) reared in black, white or green tanks (Papoutsoglou et al, 2000), beluga ( Huso huso ) reared in black, white, green, red or blue tanks (Banan et al, 2011), and thinlip mullet ( Liza ramada ) reared in black, white, green, red, yellow or blue tanks (El‐Sayed & El‐Ghobashy, 2011).…”

“…However, in later weeks they consumed the micro diet well, which probably contributed to their higher crude protein. Decreased crude ash and lipid content in larvae reared in red tanks has also been reported in the larvae of Asian Seabass ( Lates calcarifer ) (Santisathitkul et al, 2020). Low‐ash content sometimes indicates high‐quality protein with high‐level essential amino acids as reported in poultry (Shirley & Parsons, 2001).…”

“…Tank colour affects survival and growth performance (Bera et al, 2019; Ferosekhan et al, 2020; Pedreira & Sipaúba‐Tavares, 2001; Sebesta et al, 2019; Tamazouzt et al, 2000). It also affects physiological processes and behavioural responses, such as feeding (Bera et al, 2019; El‐Sayed & El‐Ghobashy, 2011; Wang et al, 2016), digestion (Rungruangsak‐Torrissen et al, 2006; Santisathitkul et al, 2020), body composition (Banan et al, 2011; Papoutsoglou et al, 2000), reproduction (Volpato et al, 2004), skin pigmentation (Eslamloo et al, 2015; Yasir & Qin, 2009) and stress response of fish larvae and juveniles (Banan et al, 2013; de Abreu et al, 2020; Sopinka et al, 2016; Wang et al, 2016).…”

“…Despite its importance in the successful management of fish larvae, there are only a few studies on the effects of tank colour on physiological responses and other attributes, such as body composition, digestives enzyme activities and cortisol levels in marine fish (de Abreu et al, 2020; Banan et al, 2011; McLean et al, 2008; Papoutsoglou et al, 2000; Rungruangsak‐Torrissen et al, 2006; Santisathitkul et al, 2020). The impact of tank colour on such characteristics at different larval stages of snubnose pompano under captivity is still unknown.…”