Does light have an influence on fish growth?

Growth and survival of dorado Salminus brasiliensis (Pisces, Characidae) post-larvae cultivated with different types of food and photoperiods

“…This strategy produced the better growth among treatments despite the fact that this species has been considered a typical visual predator. The results registered for dorado post-larvae survival and growth in LD 0:24 contrasted with other studies where better survival and growth were found with the increase of photoperiod, a response associated with various factors as the dependency of larvae visual abilities (Giri et al, 2002), the increase of predator-prey encounters (Puvanendran and Brown, 2002) and prey availability (Boeuf and Le Bail, 1999;Kestemont et al, 2003) and the insufficient time for the establishment of a robust rhythmicity plus the reduction of the standard metabolic rate (El-Sayed and Kawanna, 2004). Table 1 -Mean (± standard error) survival (%) and cannibalism (%) for dorado (Salminus brasiliensis) post-larvae, submitted to different photoperiods and fed with fish prey or Artemia nauplii after six-days of cultivation.…”

“…Photoperiod, a very important issue for visual predators (Dabrowski and Jewson, 1984;Baras et al, 2000), acts on fish activity stimulating the food consumption (Tesch, 1975;Zavala Camin et al, 1991) and can significantly affect larvae growth and survival by improving the post-larvae skills in locating, capturing and eating preys. A long day usually favors the larvae culture and the synergistic effect of food availability in relation to the length of the day seems to be a determining factor in this stage (Boeuf and Le Bail, 1999). As Salminus brasiliensis is considered a visual predator (Cecarelli, 1997), the present study aimed to investigate the simultaneous effect of light availability and food type on the growth and survival of dorado post-larvae using the standard rearing procedures and alternative ones, in order to identify mechanisms that influence the cultivation of this species during the phase where cannibalism is more intense.…”

The effect of temperature and fish size on growth of juvenile lumpfish (Cyclopterus lumpus L.)

“…Imsland and Jonassen (2001) suggested an increase in overall metabolism due to increased metabolic capacity at constant photoperiod at low temperatures, but the nocturnal activity of lumpfish is yet unknown. It has been suggested that the effect of photoperiod increases for species with a low standard metabolic rate (Boeuf & Le Bail 1999) which according to the findings of our study in terms of growth and FCE may lead us to believe that photoperiod modulation most likely would have a great effect on juvenile lumpfish growth. It has also been questioned whether the positive effect of increased temperature on growth has been related to elevated FCE or C T (Boeuf & Le Bail 1999 …”

“…Photoperiod affects melatonin synthesizing pineal and retinal cells, hence producing an endocrine and neuroendocrine signal of darkness and light through the pituitary-thyroid-axis (Boeuf & Le Bail 1999). Possible secondary effects on photoperiod should not be out ruled, as temperature -growth studies for juvenile halibut have shown enhancing effects on continuous light periods for growth at low or sub-optimal temperatures and negative effects close to T opt SGR (Jonassen et al 2000b;Lohne et al 2012), but this growth effect may be species specific (Boeuf & Le Bail 1999) and dependent on the changing optimum temperature for growth with increasing size (Imsland et al 2007b). Despite this, Lohne et al (2012) found no indications that photoperiod modulates T opt for SGR and feeding in juvenile halibut, while (Jonassen et al 2000a) found that growth in juvenile halibut would gradually increase with increasing natural day length, though not exceeding the growth of fish reared at constant photoperiod.…”

Tambaqui growth and survival when exposed to different photoperiods

“…Fish with nocturnal feeding habit, like catfishes, or those species that are aggressive, may increase food intake when held in darkness, whereas those with a diurnal habit may grow better on extended photoperiods. The work of Boef and Bail (1999) described that a fish behavior may also be modified by concomitant diurnal changes in other factors, such as temperature or oxygen availability and the mechanism of photoperiod in fish growth are not so clear. In this study, data are presented to show that tambaqui (Colossoma macropomum) juveniles exposed to continuous darkness grow better than those exposed to natural photoperiod and continuous light.…”