About Breeding Methods for African Catfish

Many types of catfish are routinely raised in large-scale fisheries. One of the most important of these, the African Catfish, is a major commercial business in its native Africa. By learning more about the feeding and spawning behaviors of these catfish in the wild, researchers have been able to help the fish farms greatly increase their productivity.

Identification

The African Catfish's natural habitat ranges from South Africa, throughout the entire continent of Africa, and into Asia. This catfish can eat both plant and animal matter, is extremely tolerant of a wide range of environmental conditions, and is not easily susceptible to disease. These characteristics, plus the fact that it takes only approximately 18 to 24 hours after fertilization for African Catfish eggs to hatch, made these fish a favorite for African freshwater fishery purposes.

Features

In the wild, African Catfish spawning takes place at night during the spring and summer, in shallow water with temperatures above 22 Celsius. The eggs stick to the leaves of stems of vegetation and, providing the temperature remains above 22 C, hatch after approximately 24 to 48 hours.

Types

In order to induce spawning artificially in fisheries, a number of hormonal preparations are used. Some of the most common include: Human Chorionic Gonadotropin (HCG), desoxycorticosterone acetate (DOCA), Carp Pituitary Suspension, Progestagen, Pimozide and LH-Rha.

Considerations

To prepare a homoplastic pituitary gland suspension, the pituitaries from several adult male catfish are homogenized in water. The resulting solution is then injected into female catfish.
After approximately 12 hours, eggs ready to be fertilized are removed from the females and are mixed with quantities of male catfish sperm. Since most catfish fisheries operate at 28 C, the fertilized eggs hatch after only 16 to 18 hours.
The newly hatched larvae are first kept in hatcheries for 10 to 15 days; they are then transferred to nursery ponds where they are fed every 4 hours. When the fish reach 4 to 5 g in weight, they are then sold or used in the fishery's production ponds.

Expert Insight

Large amounts of research have been conducting focused on enhancing the yield of African Catfish by increasing our understanding of how these fish behave in the wild. Research has provided fisheries with the following advice:
Since newly hatched African Catfish seek out dark, sheltered spots to feed, hatcheries should be shaded to reduce light.
Hatchery ponds and nursery ponds should be shallow and contain a large amount of vegetation, because these are the sorts of locations adult catfish spawn in. As the fish age, they should be moved to deeper ponds, as adult African Catfish are generally nocturnal.
African Catfish normally feed in packs. Therefore, having a large number of catfish in a fishery pond reduces aggressive behavior between the fish. Conversely, a fewer number leads to territorialism and more aggressive behavior.

Resources

• ScotCat.com provides detailed information about all types of catfish