GROW-OUT OF ABALONE Haliotis squamata IN FLOATING CAGES FED DIFFERENT PROPORTIONS OF SEAWEED AND WITH REDUCTION OF STOCKING DENSITY
Abstract: Abalone is a
herbivore marine animal which feeds on seaweed. Abalone culture has a good
prospect in terms of price, market share and simple culture technique. Thus, a
study was conducted with the aim of finding out an effective and efficient
abalone culture technique in terms of feed use and density. In this study, a 42
cm diameter plastic container with a 22 cm height was used. Three vertically
arranged containers were used as the experimental group which were put into a
net box and hung onto a raft so that the containers were placed in a 4 m depth
below the sea surface. The juvenile of abalones being used came from a hatchery
production that has been adapted to cages environment with Gracilaria sp. and
Ulva sp. feed. The initial density of abalones was 450 for each container, with
the initial weight of 2.6-3.2 g and the 2.5-2.7 cm shell lengths. The abalones
were fed with Gracilaria sp. and Ulva sp. seaweeds with different Gracilaria
sp./Ulva sp. proportions, i.e. 100/0% (A); 80/20% (B); and 60/40% (C) as the
treatments. Each treatment consisted of two replications. After three months of
rearing period, densities of abalones were reduced to be 190 for each
experimental unit. Weight and shell length of abalones were measured every
month by measuring 25 abalone samples from each experimental unit. The result
of the experiment showed that the increase in the Ulva sp. proportion in the
feed increased the growth of abalones and decreased the feed conversion.
Feeding with Gracilaria sp./Ulva sp. proportion of 60%/40% allowed the best
growth of abalones. The decrease of abalone density in the experimental unit
after three months of rearing also produced an increase in their growth.
Keywords: abalones Haliotis
squamata; grow-out; seaweed proportion; rearing density
Author: I Nyoman Adiasmara
Giri, Tatam Sutarmat, Hirmawan Tirta Yudha, Ibnu Rusdi, Bambang Susanto
Journal Code: jpperikanangg140058
