News & Views
Tips for Nigeria’s hatchery operators
By Quentin Dodd
Albert Sodunke, a fish-farming expert in Nigeria’s Ogun state, recently had some tips for the country’s African catfish farmers. Sodunke is the desk officer in the fish hatcheries certification program at the state ministry of agriculture. His advice focused on helping farmers ensure the survival of their broodstock during the Harmattan season. (The Harmattan is a winter season, characterised by dry, dusty winds and cool, volatile temperatures.)
The season can cause all sorts of problems, says Sodunke, who also has the Fish House Consult company.
Even with systems securely in place, two things are “likely” to happen: eggs only partially hatch or don’t hatch at all; or the eggs hatch but the fish only survive a few days.
Firstly, Sodunke suggests that breeders inject the young female fish an hour earlier than usual, or that they give them more time before stripping, because of the lower temperature.
Secondly, the hatchery should be well covered. Incubators should be in a well-enclosed room and the eggs should be spread lightly or in one layer per tank.
He also suggests that before spreading out the eggs or immediately afterwards, heat up the environment by using a coal pot with charcoal, a room heater, or a submersible aquarium heater.
Finally, he advises that breeders not use flow-through water during incubation during the Harmattan, but instead use “stagnant water” to prevent a sudden change in the temperature.