An economic
analysis of the performance of three sizes of catfish Ictalurus punctatus
fingerlings understocked in multiple-batch production
C.R. Engle, D. Valderrama-2001
Journal of the World Aquaculture Society, 32(4):
393-401 (from Current Contents)
Abstract :
Different sizes of catfish fingerlings understocked
in multiple-batch production stay result in different survival, yield, cost,
and economic risk. A pond production study was conducted to compare net
yield, growth, survival, costs, and economic risk of understocking 7.6-cm,
12.7-cm, or 17.8-cm channel catfish Ictalurus punctatus fingerlings in
growout ponds. Fingerlings were understocked at 15,000/ha with 1,369 kg/ha
carryover fish averaging 0.58 kg. Mean growth rate increased significantly
with size of fingerling understocked (1.4 +/- 0.2 g/d, 1.8 +/- 0.07 g/ d,
and 2.2 +/- 0.06 g/d for 7.6-cm, 12.7-cm, and 17.8-cm understocked
fingerlings, respectively). Mean individual weights at harvest also
increased significantly with size at stocking but none of the understocked
fingerlings reached minimum market size (0.57 kg) over the 201-d study
period. Survival of the smallest (7.6-cm) understocked fingerlings was
significantly lower, but there was no difference in survival between the two
other treatments. Net yields were highest fur the two treatments
understocked with 12.7- and 17.8-cm catfish and significantly lower fur the
treatment understocked with 7.6-cm fish. Growth of huge carryover fish was
significantly less in the treatment understocked with 17.8-cm fingerlings.
Breakeven production costs were highest for the treatment understocked with
7.6-cm fish and lower for the other two treatments. Tile risk analysis
showed that it was very likely that the 12.7- and 17.8-cm understocked fish
could be grown profitably (very little risk of costs exceeding
$1.32/kg-$1.65/kg). However, the risk of grossing out 7.6-cm understocked
fish at costs above market prices increased sharply. This static analysis
indicates that the preferred size to understock in growout ponds would be
12.7 cm; however, additional work is needed in a dynamic framework to
quantify the benefit of 17.8-cm fingerlings reaching market size earlier in
the second year.
(Univ Arkansas, Aquaculture Fisheries Ctr, Mail Stop
4912, 1200 N Univ Dr, Pine Bluff, AR 71601, USA)