ISSN: 0041-3216

ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 88 Number 2
Research Papers
The influence of photoperiod on growth and survivorship of fry of the armoured catfish, Hoplosternum littorale (Hancock). (102)
Small groups of larval armoured catfish, Hoplosternum littorale, were reared for a period of five weeks at three photoperiod cycles: 24L:0D; 12L:12D; and 0L:24D, and were fed live Artemia salina, ad libitum, three times daily. The fish reared in complete darkness showed the greatest increase in weight (14 433%) while those reared in continuous light had the smallest increase in weight (4 762%).These results were highly significantly different (P < 0.001; Tukey’s HSD test). A similar effect was seen with increase in length. Survivorship varied with photoperiod cycles with 80.67% at 24L:0D; 79% at 12L:12D; and 58.24% at 0L:24D, but these results were not significantly different. This study indicates that there is merit to raising larval armoured catfish in darkness due to their photophobic nature during the larval stages.
Keywords: Hoplosternum littorale; larvae; larval culture; photoperiod