Page 283 - Agriculture_Form_Three

Agriculture for Secondary Schools

(b) Age, size and sex of seed for stocking
It is important to acquire good quality seeds of similar age and uniform size for
stocking. Usually, fingerlings of at least 1 gm average bodyweight are suitable
for stocking. Fingerlings should be healthy and free of injuries and deformities.
If a pond is stocked with mono-sex seed, for example, all male tilapia, it results
in better productivity and profitability. This is because all male tilapia fingerlings
are uniform in size, grow faster and use feed more efficiently. Optimal production
requires minimised size differences in the pond. So, in-pond, reproduction should be
avoided. When using mixed-sex seed, reproduction cannot be controlled.

(c) Seed source
It is advisable to obtain fingerling from reputable, disease-free hatcheries. To
maximise production, it is therefore recommended to purchase seed from a reliable
source, like a government breeding centre, commercial hatchery or a well-known
breeder farmer. Ask the hatchery to purge the seeds before transport. Seeds should
not be bought from another farmer or from the wild. Buying wild fish will deplete
wild stock and increase the risk of disease/mortalities. Wild fish are not used to
artificial feed and they need time to adapt to a pond.
(d) Stocking time
It is advisable to stock seed during cool hours. Seeds should be released into the
pond during cool hours of the day, that is, from 18:00 to 10:00 hours. If there is
wind, stock on the windward side of the pond.

(e) Acclimatisation of seed to new conditions
Seeds have to be acclimatised to new conditions. This is done by keeping the seed
bags floating on the pond for 20 - 30 minutes before releasing fingerlings into the
pond to acclimatise with pond water temperature. Feeding the fish has to start 1 or 2
days after stocking to allow them to recover from the stress of transport.

(f) Stocking density
Stocking density depends on type of fish culture and feeding system. The stocking
density of ten mono-sex and five mixed-sex fingerlings per square metre is considered
suitable under intensive system while three to five fingerlings per square metre is
ideal in semi-intensive culture system.

Feeding of fish

High quality feed is essential to obtain high productivity and good fish health. The
following aspects have to be adhered to in feeding fish.
(a) Feed form and size
Floating pellets are recommended over mash in feeding fish. Floating pellets remain

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AGRICULTURE FORM 3 9.11.2022.indd 272 10/01/2025 12:32