What you need to know about Cat Fish

The African catfish (Clarias gariepinus) is regarded as a nutritious tasty food source in Africa and is also recognized as one of the most suitable species for fish farming in Africa

Why

Because the African catfish (Clarias gariepinus) has a high growth rate, is very resistant to handling and stress, and is also very well appreciated in a wide number of African countries and can be grown quickly.
The African catfish is a dominant freshwater fish. It can grow to between 1.4 and 2m long and can weigh anything from 1.2kgs to 4kgs.

Approximately 70 percent of feeding activity takes place at night!!!

The African Catfish body varies from olive green, to brown and black with the flanks often uniform grey to olive-yellow with dark slate or greenish brown back.
The Under parts of the African catfish are pale olive to white and are mottled irregularly with dark brownish green, or uniformly silvery olive.
It is a heavy boned, flat headed fish with premaxilla and lower jaw pointed teeth arranged in several rows and four pairs of long trailing sensory organs known as ‘barbels’ around its mouth giving it a similar appearance to a cat, hence the name catfish.

The African Catfish has a high number of gill rakers varying from 24 to 110, the number increasing with the size of the fish.
The body is elongated with long, low dorsal and anal fins and a smoothly rounded tail fin. The skin of the African Catfish is leathery and has no scales. It has a small but powerful pectoral fin set immediately in front of the anal fin which has a serrated spine.
The eyes are small and set far forward in a flat and bony head.
At the back of the head there is a subsidiary breathing organ above the gills which enables this animal to breathe air directly.

Feeding Catfish

The African Catfish is a ferocious feeder and feeds on a large variety of agriculture by products. .
In the wild, the African catfish hunt socially; swimming in formations on the water surface or in a claw like formation to the shore.
When they come against prey that they like, they herd the prey fish they like (e.g cichlid prey fish like the tilapia fish) towards the shallows where they can easily catch these fishes.
The mouth of the catfish is wide, sub terminal, traverse and capable of opening extremely wide for engulfing prey items or sucking in large amounts of water which is flushed through the gills for filter feeding.
Once the prey is in the mouth, the jaws snap closed and the broad bands of sharp teeth on both the upper and lower jaws prevent the prey from wriggling free. The prey is swallowed whole.
The esophagus is short, muscular and dilatable. It opens into a distended stomach typical of creatures capable of carnivory. Most species of Clarias are slow foraging predators.
They use their four pairs of barbels to feel their way around in the dark and find food detected by the array of sensitive taste buds covering the barbels and head.
Approximately 70 percent of feeding activity takes place at night.
The African Catfish are bottom feeders which occasionally feed at the surface.
The African catfish is a general scavenger and known as an opportunistic omnivore in that it feeds on a wide variety of plants and animal matter.
They can feed on insects, crabs, plankton, snails and fish but also take young birds, rotting flesh, plants and fruits.
Larvae are almost exclusively dependent on zooplankton for the first week of exogenous feeding.
Large C. gariepinus, because of their high number of gill rakes, also target zooplankton as a primary food source. Although generally omnivorous, C. gariepinus relatively better digests high-protein diets than carbohydrates.
The Adult African Catfish has diel feeding pattern meaning that they do not need to hunt for food for more than once a day as they have a relatively large stomach capable of holding quite a lot of food, Unlike the Nile tilapia fish which has a smaller stomach and therefore needs to feed several times a day.
It is this fact that the African Catfish is omnivorous and has a wide selection of food that makes the African catfish ideal for the business of fish farming especially in the African environment.

African Catfish– Reproduction

The African Catfish (Clarias gariepinus) is a non-guarding, substrate spawner.
It tends to breed naturally in very shallow, weedy waters normally after heavy rains and usually once the fish have migrated upstream.
Catfish tend to migrate upstream in the wild after heavy rains, often within 2 to 3 days of the new moon of the last quarter.
Without these specific conditions being met… the African catfish will not breed naturally In areas with two rainy seasons, there are usually two reproductive peaks during the year, corresponding in intensity to the magnitude of the rains.
The average number of eggs produced is 45 000 eggs for a 2kg fish.
The medium, minimum population doubling time is between 1.4 and 4.4 years.
This catfish can walk short distances to new breeding areas or through very shallow damp pathways.
African catfish reach maturity at the end of their first year of age when they are approximately 20 to 25cm in length Courtship, spawning and egg deposition take place at night with the peak spawning times between 20h00 and 02h30.
Prior to mating, males compete aggressively for females with which they mate in single pairs Tiny fertilized eggs hatch out within 24 to 36 hours of being attached to plants and debris in the water.
The larvae swim after 50 hours and begin to feed at 80 hours. The yolk sac is absorbed within 3–4 days and the stomach is fully functional within 5–6 days after onset of exogenous feeding.
Sexual differentiation begins between 10 and 15 days after hatching.
Larvae feed and grow rapidly in the warm (usually >24 °C) nutrient rich floodplains, reaching 3-7 g within 30 days.
As flooded marginal areas dry up with the end of the rains, juveniles and adults make their way back to deeper water.

Site Selection and Placement of Cages

Large bodies of water tend to be better suited for cage culture than small ponds, because the water quality is generally more stable and less affected by fish waste. Exceptions are entropic waters rich in nutrients and organic matter. Small (1 to 5 acres) ponds can be used for cage culture, but provisions for water exchange or emergency aeration may be required.
Cages should be placed where water currents are greatest, usually to the windward side. Calm, stagnant areas should be avoided. However, areas with rough water and strong currents also present problems.
Cages may be moored individually or linked in groups to piers, rafts, or lines of heavy rope suspended across the water surface. At least 5 meters should separate each cage to optimize water quality.
The cage floor should be a minimum of 4 meters above the bottom substrate, where waste accumulates and oxygen levels may be depressed. However, greater depths promote rapid growth and reduce the possibility of parasitism and disease.

Catfish Farming As a Business

The African Catfish is a ferocious feeder and fast growing fish. It feeds on a large variety of agriculture by products.
It can be raised in high densities resulting in high yields of up to 20,000kg of fish per hectare just by rising in ponds and using a complete pelleted diet. It also tends to fetch a higher price than that of tilapia because it can be sold live at the market.
They are relatively insensitive to disease and do not have high water quality requirements. The African catfish can also tolerate low oxygen concentrations because the fish has the ability to utilize atmospheric as well as dissolved oxygen to breathe because it has air breathing organs that are well developed.
The African catfish can also be raised using different production systems ranging from the static earthen pond production system where the fish just feeds on natural zooplankton and insects in the pond to high tech stuff where the fish are fed intensively using more sophisticated systems
The fact that the African catfish can be produced without powered aerators or high tech equipments together with all the facts mentioned above make the African catfish an excellent fish to farm especially in developing countries where access to investment capital and high tech equipments might be limited.