Fish as feed inputs for aquaculture: practices, sustainability and implications

102 Fish as feed inputs for aquaculture – Practices, sustainability and implications

FIGURE 16

Lines of best fit depicting the relationship of the cost of production to conversion efficiency

(CE) on grouper farms in three countries (a) Thailand, (b) Viet Nam and (c) Thailand, Viet Nam

and Indonesia combined

of CE with commercial pellet feed and unit production. Furthermore, CE was not

related to farm size in any of the countries.

Based on a simple comparison, trash fish/low-value fish appear to be economically

more viable, if issues relative to sustainability and the environment are not taken into

account. In Table 16, it is reported that the equilibrium price level for trash fish/low-

value fish is at a price of US$0.20/kg and a CE of 13.20 for Viet Nam. If CE level is

maintained below 13.0, feed cost saving (although minimal) will result in profitability

for small-scale farmers. If the CE falls below 10.0, significant saving in feed cost leads

to more a profitable business for small-scale farmers.

Overall, CE is an indicator of the feed efficiency of each farm. Leung, Chu and Wu

(1999) reported that areolate grouper (E. areolatus) fed trash fish/low-value fish had a

CE of 6.52. Although Yap et al. (2006) indicated that the CE for trash fish/low-value

fish should range from 5 to 10, Orachunwong, Thammasart and Lohawatanakiul (2006)

estimated that CE for trash fish/low-value fish ranged from 8 to 15. This suggests that

improvements could be made in the efficacy of trash fish/low-value fish usage in

grouper farming that would reduce the overall quantity of resource used, which in turn

would improve the sustainability of grouper farming in the region (Box 6).

5.2 Trends in the use of trash fish/low-value fish in freshwater aquaculture in

the Asia-Pacific region

Compared with the use of trash fish/low-value fish in marine and brackishwater

aquaculture in Asia, its use in freshwater aquaculture is relatively less and is also

localized. The number of freshwater carnivorous finfish species cultured in Asia

y = 0,586x + 0,837

R² = 0,906

2.0

4.0

6.0

8.0

10.0

12.0

14.0

7.0 12.0 17.0 22.0

Cost of production (U S$/Kg)

a .T hailand (trash fish)

CE

y = 0,292x + 5,535

R² = 0,337

4.0

5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0

0.0 5.0 10.0 15.0 20.0

Cost of production (U S$/Kg)

CE

b. V i e t Na m (tr a s h fi s h )

y = 0,292x + 5,215

R² = 0,358

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0

0.0 5.0 10.0 15.0 20.0

Cost of production (U S$/Kg)

CE

c .T hree countries com bined (trash fish)

Source: Sim (2006)

Note that for Indonesia data for only two farms were available