Enzyme, Pharmaceutical Aids, Miscellaneous Last Part of Chapter no 5th.pdf
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1. Catfish Management and It’s
Operation
March 8, 2024 MA. LISSETTE F. PERMOCILLO, Aquaculturist II, PFO-Iloilo
2. Introduction
Catfishes are widely distributed in many countries in Asia, Africa, Europe
as well as Central, South and North America.
Some species form a significant part of inland fisheries, several have been
cultured, and many species are of interest to the aquarium industry
Most catfishes in the Philippines are under the Family Clariidae.
African catfish inhabit calm waters from lakes, streams and rivers to
swamps, some of which are subjected to seasonal drying.
3. Biology
Displaying an anguilliform shape, having an
elongated cylindrical body; dorsal and anal fins
are extremely long, nearly reaching or reaching
the caudal fine; both fins contain only soft fin ray.
The outer pectoral ray has a spine.
Pelvic fin normally has six soft rays.
Head is flattened and the body is covered with
smooth, scale less skin.
4 pairs of unbranched barbels one nasal, one
maxillar (longest and the most mobile) on the
vomer and 2 mandibulars (inner and outer) on the
jaw.
Tooth plates are present on the jaws as well as on
the vomer.
4. Biology
Clarias species have a scale less skin and darkly
pigmented in the dorsal and lateral parts of the
body.
Color is uniform or marbled and rages form
grayfish alive to blackish according to the substrate
and exposed to light the color becomes lighter.
It enables to migrate over land.
C. gariepinus feed mainly on aquatic insects fish
and debris of higher plants.
They also feed on terrestrial insects, molluscs and
fruits it may be considered as an omnivorous fish
with a high tendency to predation.
The catfish grasps its prey by sunction.
The most studied and of great importance in
fisheries and aquaculture among clariid catfishes
are the Asian catfishes Clarias macrocephalus and
C. batrachus, and the African catfish C. gariepinus.
5. catfish in the
philippines
Native catfish (Clarias macrocephalus)
• Indigenous in the Philippines
• Max length – 20 cm
• Max weight – 180 grams
• Max age – 8 years
• Blunt occipital process
6. catfish in the
philippines
Thai catfish (Clarias batrachus)
• From Thailand
• Max length – 100 cm
• Max weight – 450 grams
• Max age – 8 years
• Pointed occipital
7. catfish in the
philippines
African catfish (Clarias gariepinus)
• from Africa
• Max length – 170 cm
• Max weight – 60 kgs
• Max age – 8 years
• Crooked occipital process
8. Natural Breeding
The natural breeding season
in catfish varies from place to
place, but usually starts during
the rainy season.
Although catfish contain
unfertilized eggs year-round
upon reaching maturity, these
are not released
spontaneously when catfish
are held under captive
conditions
11. Ideal Pond Design
- must be rectangular in shape.
- the shallow end should be 0.75 - 1 m deep and sloping to 1.5 -
2 m deep.
- dike should be trapezoidal in shape.
0.75-1 m
1.5-2
m
Dike-½ m over the
highest flood level
Water
level
Water inlet
Pond bottom Water outlet
Flow through pipe
12. Grow-out Culture in Ponds
Pond size – 50 sq.m. or more depending on the capital investment.
Water depth – at least 1 meter or higher depending on the stocking rate.
Enclose by nets – prevent the entry of predators just like frog and to
prevent the escape of stocks during flood or overflow of water in pond
during heavy rain.
16. Stocking
when there is sufficient natural food in the pond (indicates green or
greenish-brown water color).
stock fish early morning or late in the afternoon where the
temperature is at low level.
Sorting is necessary every 15 days to prevent cannibalism.
Stock fingerlings that are:
of good quality/from a reliable source
similar age and size (preferred size 5-6cm)
healthy
21. How to determine fertility of
water?
Siko Method
practical way of
determining phytoplankton bloom
Water Management
22. How to determine fertility of
water?
Secchi Disk
should have a reading of 30 – 35 cm
Water Management
23. How to determine fertility of
water?
Secchi Disk Visibility Evaluation
Water Management
Secchi Disk Reading Plankton Turbidity
˂20 cm Pond is too turbid
Problems on high respiration rate
20-45 cm Pond is in good condition
45-60 cm Phytoplankton becoming scarce
˃60 cm Water is too clear
Inadequate productivity
25. Maintenance
Fish kill may be due to:
thermal shock/abrupt change in temperature
very low dissolved oxygen
presence of ammonia and hydrogen sulfide (poisonous gas which evolves from the
pond bottom as a result of decaying and decomposing organic matter)
heavy water current
Diseases
27. Winter saprolegniosis or winter kill syndrome is a type of fungal disease
which occurs in cold water, therefore the fungus had the opportunity to
spread and kill the fish.
Sample of Disease
Fungus
30. Feeds and Feeding Habits
Carnivorous (90% protein and
10% carbohydrates)
Food materials used are ground
trash fish, earthworm, termites,
maggots, insects, slaughterhouse
by-products, chicken entrails,
freshwater shrimps, and by
products of canning factories.
Boiled broken rice mixed w/
vegetables or rice bran can be
substituted.
Commercially prepared catfish
feeds are readily available in the
market.
33. Feeding
The mixtures were hand mixed and minced in a meat mincer to
form a slurry and hand distributed into the ponds until it was all
used up or until the fish area no longer respond to the food.
35. Computing Daily Feeding Rate (DFR)
and Average Body Weight (ABW)
DFR = (total stocks - mortality ) X Average Body Weight or ABW X
feeding rate
Example : ABW 15g/pc., total stocks 2,000pcs., feeding rate 5% and
Mortality 10pcs. Solve for Daily Feeding Rate (DFR)
DFR = (2,000pcs. – 10pcs.) x 15g x 5% = 1,492.50 grams per day
37. Pond Freshening and Dressing
Introduce water in pond every 15 days (if possible) for about 1hr. between 5-6
am or before sunrise to increase oxygen level and to prevent fouling of water.
Pond dressing can be done using the “tea bag” method and place near the
water inlet.
Culture Period
Rearing of Catfish w/ proper management Last
from 2.5 - 3.5 months under favorable conditions.