Fish Harvesting and Post-Harvesting Processes
Materials and methods for harvesting fish
Various types of gears:
- Spears
- Knives
iii. Traps
- Hooks and line
- Cast nets
- Gill nets
vii. Drag nets
viii. Trawl nets
Various fishing crafts:
- Dug-out canoe
- Wooden/flat bottom canoe
iii. Motorized canoe
- Dingy
- Trawlers
Methods of harvesting:
– Using hooks and line
– Spearing
– Netting
– Trawling
– Draining the water (partial or complete)
Construction and mending of the cears.
Post harvesting process
Processes of:
– De-gutting
– De-gilling
– De-scaling (for fish with scales)
– De-capitation (in cases of large size fish)
– Washing properly with clean water
(a) materials for Processing:
– knives
– basins
– Tables
– Cutting slabs, etc
(b). methods Preservation:
– sun drying
– wet smoking
– dry smoking
– frying
– freezing
– filleting
– cannina
Packaging materials: Nylon\cardboard box baskets
Primary and Secondary markets (e.g. fishmongers, bars/restaurant, supermarkets hotels etc.
Seed Production
Brood stock selection and handling
Differentiate between male and female sexually mature fish using sex organs.
Stripping them to know the stages of sex gametes (egg and milt).
Qualities of good breeders:
- Hardyvactive
- Have matured gametes
iii. Fairly big size
Brood Stock handling:
- Ensure transportation takes place in the morning or late in the evening
- Allow a shorter period time (48 hours to one week) in a breeding compartment
iii. Ensure careful handling of the breeders to avoid stress.
Fish Seed Production
Artificial breeding
Artificial breeding:
– manipulating the sexually matured fish to spawn or reproduce.
Importance of artificial breeding:
- To obtain fish
- To obtain large quantity of fish
iii. To obtain high quality hybrids
- To make thefingerlings readily available
Various steps:
- Brood stock selection
- Conditioning of brood stock
iii. Inducement of the brood stock
- Stripping the brood stock
- Fertilization (mixing the milt and egg)
- Incubating the fertilized egg in aquarium or hatchery tanks/trouqhs etc.
Managing and nursing fish feed
The nursing processes:
- Aeration
- Feeding with natural food organisms (plankton) after four days
iii. Introduction of artificial feeds (powdered feeds after one week)
Management processes:
- Separating dead/unfertilized eggs from the hatchlings
- Monitoring water quality (especially the Dissolved Oxygen (DO), temperature, etc)
iii. Transferring outdoors to nursery tanks/ponds after 21 days
- Sorting the shooters/jumpers from the stunts.
- Rear or raise the jumpers separate from the stunts.