How Niger resuscitates Tagwai fish hatchery

The idea of resuscitating the hatchery was borne out of the need for the state to establish a training institute that will enable its indigenes to acquire knowledge on how to culture some of the indigenous fish species for maximum productivity and to fight unemployment.Dr. Gabriel Bake, consultant, Tagwai hatchery project and lecturer with the […]

The idea of resuscitating the hatchery was borne out of the need for the state to establish a training institute that will enable its indigenes to acquire knowledge on how to culture some of the indigenous fish species for maximum productivity and to fight unemployment.
Dr. Gabriel Bake, consultant, Tagwai hatchery project and lecturer with the Federal University of Technology, Minna, told this reporter that the state government engaged his services in 2011. He was brought in to give consultation services as well as to expand the hatchery project.
Bake said he met the hatchery in a situation far below the standard the government wanted to set for providing a hatchery capable of supplying the 19 northern states with fingerlings.
He stressed that to achieve the target set by the state government, it undertook the rehabilitation and expansion work at the project site, while plans have been concluded for the construction of incubation ponds for the production of tilapia species of fish.
Dr Bake lamented, however, that after a certain level of progress was recorded at the first phase, the project suffered a setback in 2012 as the money meant for the project in that year’s budget could not be accessed. However work has resumed in earnest last year (2013) as progress was made on the feed mill.
With the state’s comparative advantage in fishery resources, the production of tilapia has become necessary because, according to him, “it is only in Africa, perhaps Nigeria that cat fish is popular. The world over, talking of international market, you only get tilapia because it is the second most cultured fish in the world after carps.”
Dr Gabriel dismissed the notion that tilapia does not grow big. The problem most people encounter in farming tilapia is that they do not know how to culture tilapia. Culturing this particular specie requires a lot of technical know- how, which is lacking among most people, he said.
 To culture tilapia, one needs manipulation of genes and breeding by oneself without allowing nature to interfere. Tilapia grows faster to maturity than catfish because tilapia in its natural environment can weigh up to 500 grams in six months.
“ One does not need to feed tilapia in same manner you feed catfish, when it is three months old, you do not need to give nutritious feed anymore because tilapia has the ability to convert its lipid (carbon hydrate). Tilapia does not need fully saturated lipid because they can easily break it down and use it.”
When tilapias are on good diet and well conditioned they can breed sufficiently; one is guaranteed to breed every two weeks for over a year. Though tilapia must be conditioned under a specific temperature of between 28 to 29 degrees centigrade and when fed very well within two weeks, you will start to get eggs.
According to the consultant, when you want to breed catfish, you must sacrifice the males (the males are killed by removing their testes), unlike in tilapias and carps fishes. If you press the males of each of the species meat (sperm) will be produced but while doing that one needs to be very careful in securing the sperm because it can come with urine mixture.
There are some technicalities that can be deployed for obtaining a clean meat; the fish needs to be turned to give out the urine for about 3 to 5 times and when that is done it cannot give out urine again. After collecting the clean meat you will subject it to fertilization, eight hours later reproduction process will begin. These species will not hatch until after 40 days.
The process of hatching is another different procedure, because for catfish you must put it in the air or on any substance that will allow the eggs to float on top of water. You must maintain the range of temperature at between 28-29 or 30 degrees. In this condition catfish can hatch after 14 hours.
But for tilapia, one needs to have what is called Zurjar (syringe like instrument) where the eggs will be placed and drain the water slowly and steadily otherwise the eggs will be turned.
“You know we are always trying to mimic their natural environment. In its natural environment a female tilapia holds its egg in the mouth for four days, it doesn’t eat at this period. All they do is turning the eggs in their month for required temperature and care.
“Tilapia has parental care whereas catfish does not. Once catfish lays eggs whether they have hatched it or not is not it problem, it will go away. Though catfish produces more eggs than tilapia, this is one of the major differences in their physiology.
For the carp fish, their optimum production depends on season. Their production period depends on ceaseless rainfall that can last for a week. It is at this period that they are supposed to be injected with meat and production begins. Carps can be easily broken down because they can be stimulated by rainfall.
In tilapia,  farmers don’t need to inject hormones when they want to break them down; all that is needed is to condition them by monitoring their photo period; that is the amount of sunlight and darkness per day. In 24 hours farmers have target, the number of hours and darkness for the fish, this easily stimulates them through temperature and feeds to start producing eggs.
In carps farmers have to inject the hormones for a specific time called latency period after which the injected hormones will trigger reproduction in the head of the carps.”
The consultant also condemned the crude practice of injecting catfish with hormones and after 8 to 12 hours one start to press them for meat when there are laid down processes for doing so. Before pressing for meat they needed to be sedative. But before that one must know the required dose as well as the time under which the fish will remain under sedative, otherwise they will die.
In circumstances like this, 5mg of hormones is given for particular weight of fish, hence the reason why every hatchery must have sensitive and weighing balance so that you will be able to know the amount of hormones to administer. If the farmers do not monitor the weigh and wrongly give more than the weight can carry, the fish will end up losing the eggs before maturity and if given less, it takes longer time to mature.