The impact of live food enrichment on the growth performance and survival rate of thin-lipped mullet, Liza ramada larvae

Abstract

Keywords:Liza ramada growth performance Brachionus plicatilis Nannochloropsis oculata Live foodThe feeding success of Liza ramada larvae at early developmental stages depends on the provision of suitable food and rearing environment and on the visibility and adequate density of the prey. In the present study, the suitability of the marine enriched rotifers, Brachionus plicatilis as a starter food followed by enriched Artemia nauplii and their effects on the growth performanceand survival ratewere investigated for rearing of Liza ramada larvae.Induced spawning of mature Liza ramada breeders was done to produce the larvae. After hatching, the larvae were stocked at a density of 20 larvae/l in 50-l glass aquaria, under different feeding conditions for three periods; green water conditions; with Nannochloropsis oculata (2.5×10 5 cells/ml) for 7 days, rotifers (8-10 individuals/ml) for 28 days and Artemia salinanuplii (4-6 individuals/ml) for 28 days. Four groups were applied for both rotifers and Artemia; green water conditions with rotifers or Artemia enriched with N. oculataor yeast and clear water conditions with rotifers or Artemia enriched with N. oculata or yeast.The results showed improvement in growth and survival rates of Liza ramada larvae fed on green water with Brachionus plicatilis or Artemia salina enriched with N. oculata at the end of 7 th day, 35 th day and 63 rd day post-hatching, respectively. This indicates that the algae N. oculata is essential not only for feeding requirement of larvae at first feeding but also for water quality improvement. Larval wet weight varied significantly between the treatments. However, the final length of the larvae did not vary significantly between the treatments.In conclusion, the presence of green algae Nannochloropsis oculataduring Liza ramada larval rearing, in water or as enrichment media for live food, is essential not only for growth performance but also for raising survival rate.