International Journal of Aquaculture, 2018, Vol.8, No.12, 90-97
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3 Adaptive Changes
Several alterations modifications in the pre stocking and post stocking management practices from the ones
originally advocated during its inception in the seventies have been made by the farmers based on their own
experiences through ages (Table 1).
Table 1 Notable alteration from the classical package of practice by the farmers in different stages of management
Variables
Classical package of practices
Farmers’ practice in practical field (>60% farmers)
Pre stocking
/
/
Excavation of mud
Yes
No
Racking/ploughing
Yes
No
Use of mohua oil cake
2,500 kg/ha
>2,500 kg/ha
Doses of agricultural lime
250 kg/ha
≥350 kg/ha
Use of cow dung
10,000 kg/ha
>10,000 kg/ha
Water test
Yes
No
Eradication of aquatic insects
Using of Soap-oil emulsion
No
Stock
/
/
No. and name of fish species
6; catla, rohu, mrigal, silver carp,
grass crap, common carp
7-10; catla, rohu, mrigal, bata, silver carp, grass crap,
common carp, japani punti, sar punti, big head carp
Stocking density(nos./ha)
7,500-10,000 nos./ha
15,000 nos./ha
Stocking ratio
1.5:2:1.5:1.5:2:1.5
Highly varied
Stocking frequency
1
>1
Post stocking
/
/
Use of medicine/vitamin/antibiotics No
Yes
Supplementary feeding
Rice bran + ground nut oil cake
(GOC)
Rice bran + ground nut oil cake (GOC) + mustard oil cake
(MOC) + dry bread or biscuit + animal sources protein
Supplementary feeding (%)
of body weight
4%
7.5% (≥500g body weight), 4.6% (>500 g body weight)
Netting
Monthly
According to market demand
Before stocking of the desired species, most of the farmers (65%) in East Burdwan and 24 Pgs (N) district, West
Bengal, used to apply mohua (
Bassia latifolia
) oil cake either for eradication of unwanted species or as manure
without considering the water depth at extremely variable rates which is a distinct deviation from the advocated
dosage of 2,500 kg/ha/m depth of water (Mondal, 2014; Biswas et al., 2017). Similarly, most fish farmers apply
agricultural lime @
≥
350 kg/ha without measuring the soil or water pH (Mondal, 2014; Biswas et al., 2017).
With regards to aquatic insect eradication, Mondal (2014) observed that in East Burdwan district, West Bengal,
India that, none of the farmer use soap-oil emulsion as usually recommended in prestocking pond preparation of
composite farming of carps during the early seventies. Instead, most of fish farmers eradicate aquatic insect both
through repeated netting and pesticides viz. Nuvan (Dichlorvos or 2, 2-dichlorovinyl dimethyl phosphate), Ustaad
(Cypermethrin) etc. Similar observation has beenreported by Biswas et al. (2017) in 24 Pgs. (N) district; West
Bengal regarding aquatic insect eradication.
Regarding stocking frequency, nearly half of the fish farmers in the above stated districts of West Bengal, India
stock their ponds one to three times in a year. About 66.67% farmers practice six species combination and the rest
prefer more than six species combination (Mondal, 2014). Majority of the fish farmers (47%) stock 10,000-15,000
nos./ha while 44% of the farmers stock more than 15,000 nos./ha (Mondal, 2014; Biswas et al., 2017) against the
original recommendation of 7,500-10,000 nos./ha. With regards to species combination, 45% of farmers follow the
classical six species combination for their composite fish farming, 25% of farmers preferred to culture IMC with
minor carps like bata (
Labeo bata
) and sar punti (
Puntius sarana
) substituting grass carp (Mondal, 2014). This is
in contrast to Biswas et al. (2017), who stated that, the classical six species combination and ratio of IMC and exotic
carps are not being followed by any of the farmers in the surveyed areas of 24 pgs (N) district of West Bengal.
