Evaluation of Bamboo, Coconut Shell Substrates and Supplemental Feeding on the Growth of Pearlspot, Etroplus suratensis (Bloch) Fry in Low Volume Cages
Evaluation of Bamboo, Coconut Shell Substrates and Supplemental Feeding on the Growth of Pearlspot, Etroplus suratensis (Bloch) Fry in Low Volume Cages
Date
2017
Authors
Sukumaran, K.
Thirunavukkarasu, A. R.
Kailasam, M.
Sundaray, J. K.
Biswas, G.
Kumar, Prem
Subburaj, R.
Thiagrajan, G.
Venu, S.
Journal Title
Journal ISSN
Volume Title
Publisher
Fishery Technology
Abstract
The 90 days experiment aimed at understanding the
scope of utilising periphyton substrates for cage
culture of pearlspot fry. The experiment evaluated
coconut shells relative to bamboo as periphyton
substrates for pearlspot culture. The experiment
constituted six floating cages (1x0.75x1 m3) each
partitioned into two to get 12 experimental units
into which 360 pearlspot fry (avg. wt. 3.55±0.17 g)
were equally distributed. The experiment constituted
of four treatment; TB: substrate (bamboo-strip
mats), TC: substrate (coconut shells), TB+F: substrate
(bamboo-strip mats) + supplementary feed,TF: supplementary
feed, in triplicates. The substrates provided
a surface area of ~ 1.9m2 unit-1. Feeding in TB+F and
TF was done using commercial carp feed (crude
protein- 32%; crude lipid- 5%) twice daily approximately
at 10% of the body weight initially upto 30
days and subsequently the feeding rate was reduced
to 9 and 8% of body weight after 30 and 60 days
respectively. Sampling was conducted every 15 days
to assess fish growth and survival. Relatively higher
specific growth rate (SGR) recorded in TB+F over TF
during the initial phase of the experiment indicated
the ability of pearlspot to utilise periphyton
efficiently in the early stages. Final SGR of 1.2 and
1.5% day-1 in TC and TB respectively indicates that
periphyton can support the growth of pearlspot.
Higher SGR and percentage weight gain in TB
(1.50±0.07% day-1; 288.10±26.69%) relative to TC (1.26±0.12% day-1; 215.90±36.37%) shows that bamboo
is superior periphyton substrate for pearlspot
culture. Lower yet statistically similar growth rates
of pearlspot in Tc relative to TB together with low
cost and easy availability of coconut shell substrates
indicates that these could be used as alternative
periphyton substrates for fish culture.
Description
Keywords
Periphyton, substrate, cage culture, Etroplus suratensis