Catfish Flashcards
what is the order of catfish for culture
Siluriformes
name two catfish that we’re looking at
- Ictalurus fureatus: blue catfish
- Ictalurus punctatus: channel catfish
3 sectors in the US industry
i) hatchery farms
ii) grow out (buy fingerlings and produce 0.5-1.5kg fish
iii) fee fishing ponds
Vietnam cultures what kind of fish?
Pangasinodon hypophthalamus
Pangasius boucourti
Europe cultures what kind of fish? for what?
wels, sheatfish.
- commercial, enhancement
- use to control excess reproduction in carp and trench ponds
SE Asia and Africa cultures what fish?
- clarias. walking catfish
- tolerate extreme densities, breathe air
- fast growth 10-500g in 6 months
- fair food, good CE
what fish does N.America culture?
- channel and blue : widely enhanced, big commercial
- Flathead catfish : Pylodictus olivaris. widely enhanced
Blue catfish:
- scientific name **
- general facts
Ictalurus furcatus
- biggest in N.A
- 150lbs max
- poorer growth and survival in the 1st year
- few growers, 5% US production
Channal Cats
- scientific name **
- general facts
Ictalurus punctatus
- identify by black spots
- up to 50lb
- no reproduction in culture
- easy spawning
- do well on pellets
- good CE
- high densities
- good disease tolerance
oxygen for catfish ponds
- 1-5ppm survive but grow poorly and dont spawn
- P.L (protection level) >5ppm
- Alkalinity - 50-400ppm
- Ca+2 10-160ppm
- iron <103%
- Temp 25-32*C ideal
4 steps of production cycle
i) spawn - spring and early summer
ii) fry stocked into nursery ponds, grow over summer and fall. Grade and over winter
iii) fryinto grow out in spring
iv) grow over summer and erarly fall, harvest in fall and early winter.
3 spawning options for catfish
i) pond method
- most common
ii) pens spawning - in ponds or raceways
- selective breeding or hybrids
iii) aquaria
- small scale and research
Brood care and selection
male fish mature at 2 years
female mature at 3 years
brood > 1.5kg up to 5kg
2 methods of sexing catfish
i) body confirmation (males bigger, wider heads, slim body at spawning. females narrower heads, and swollen body)
ii) UG openings: (males: sperm and urinary opening are the same, have UG papillae. females: separate urinary and genital openings in cleft or slit)
where do you select your brood from for catfish?
from all in all out growout
males and females from different stocks
where do you keep your catfish brood?
low density small pools
what do you feed catfish brood?
35% protein, fed at 3% bw/d in summer and less in winter. forage fish
low large are catfish brood ponds?
2-4ha
what is the sex ratio for catfish brood?
60%female, 40% male
female catfish egg production?
6500egg/kg
survival rate for catfish eggs-to-swimup?
egg to swim up 60-70% survival
suvival rate for catfish swim-up to fingerling?
60-70%
describe catfish pond spawning methods
- fish choose own mate
- must have spawning container
- container spaced 2-10m; shallow water
- 1 container/2-3 males
- marked with float or stake
- check every 3-4 days
- eggs removed and taken to hatchery
describe catfish pen spawning method
- selective breeding
- pens 1x2m -1m deep
- frames 2x4 driven into bottom and mesh sides