hatcheries on their farms and
produce fingerlings for stocking
into their food fish production
ponds, most farmers buy
fingerlings. Catfish hatcheries can be simple to complex in their
design. The design and intensity of
production depend upon the
market and objectives of the
operation. Fingerling markets may
include food-fish producers, recreational fishing and home-use
production. A potential fingerling
producer should study the market
to avoid economic losses because
of insufficient demand. Broodstock Selection As in other animal enterprises, the
quality and quantity of the young
produced are directly related to
the quality of the broodstock. For a
successful fingerling operation, use
the best broodstock available and provide proper care for it.
Broodstock selection factors
include: 1. Fish should be 3-10 pounds and 3-6
years of age. 2. Fish recently taken from the wild
should be avoided. 3. Fish from sources having a history
of catfish virus disease should be
avoided. 4. Fish should be full-bodied with no
visible signs of sores or
hemorrhages. 5. A ratio of about three females for
every two males is recommended. Determine the sex of each brooder
(Figure 1). Primary and secondary
sex traits are used to separate
males from females. Body shape
and color are examples of
secondary traits. Mature males usually have a larger, broader and
more angular head than females of
the same size. Near spawning time,
males develop muscle pads on the
head and become very dark grey
to black. Just before spawning, females have soft, swollen bellies
due to egg development. Never use secondary traits as the
only method to identify males and
females. These traits may not be
apparent in younger fish. The sex
should be confirmed by examining
the genitals. There are two openings on the belly. The opening
nearest the head is the anus and
the one nearest the tail is the
genital opening of both sexes. Just
before the spawning season,
female genitals are red, swollen and sometimes pulsating. In the
off-season, the area is oval and flat.
In the off-season, the male genital
is less oval than the females. Just
prior to the spawning season, a
swollen, nipple-like genital papilla may be seen on the males. Broodstock must be in good
condition for optimal spawning
success. Provide a quality ration
daily during warm weather. When
water temperatures are below
65°F, feed every other day at 1% of their body weight. At
temperatures below 55°F, fish may
not feed. Fish should gain about
50% of their body weight from one
spawning season to the next. Stocking weight of broodfish
should not exceed 800-1,200
pounds of fish per acre at any time
during the year. Broodstock with
deformities and other problems
should be sorted, culled and replaced each year. To avoid
possible loss of all brooders, keep
fish in more than one pond. Spawning Channel catfish spawning activity
begins in the spring when water
temperatures reach about 75°F.
Five pound and larger female
catfish spawn 2,000 to 3,000 eggs
per pound of body weight; smaller females, about 4,000 eggs per
pound of body weight (Figure 2). Place spawning containers in 2-3
feet of water, 1-10 yards apart,
when the water is about 75°F. The
containers can be wooden boxes,
ammo cans, drums, etc. They must
be large enough to accommodate the breeding pair. There are three methods of
producing catfish fry: Spawning and rearing in the
pond Spawning containers are placed in
the pond; brooders and fry are left
in the pond until harvest. This
method is not recommended
because the manager never knows
how many fish are present until harvest. Survival is usually poor
and the method is unreliable.
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