Survival and growth of Pseudoplatystoma corruscans (Pisces - Pimelodidae) larvae: effect of photoperiod

The survival and the growth of Pseudoplatystoma corruscans larvae exposed to four photoperiods: light:dark (LD) 0:24, LD 10:14, LD 14:10, and LD 24:0, in a brackish water (5‰) culture were analyzed. Larvae were fed with Artemia sp. nauplii at a 500 nauplii/larvae/day ratio. Survival on day 5 was inversely related to the length of photoperiod. From days 5 to 10, intermediate photoperiods resulted in a better survival, although LD 0:24 and LD 14:10 resulted in similar survival on day 10. Larvae presented higher weight at intermediate photoperiods. The results suggested that photoperiod requirements shifted during early development of P. corruscans larvae.