A catfish hatchery is a farm where the artificial hatching of catfish eggs is carried out. These eggs that are hatched via artificial means are nurtured and managed until they mature into fingerlings which are usually between 6-8 weeks old. Fries, fingerlings, or juveniles are the products that are gotten from a hatchery. For any type of fish farming, fingerlings are very essential to the farmer as without them there is no stock for their fish farm. Hence, hatcheries are an important aspect of fish farming, and the state of the fish farming market in Nigeria has also affected the fish hatchery business as it is also a lucrative aspect because these booming fish farms depend on the hatcheries to be functional.
To essentially set up a catfish hatchery, these are some steps to consider;
Site Selection
Selecting a site for the location of your hatchery is one of the most important steps as this contributes very much to the operation of your farm. The site should be close to a water source such as a borehole, etc. To avoid death while transporting them for sale, your hatchery should be located close to a fish farm so that they can be easily relocated into their new habitat. Ensure the water flowing into your hatchery is not polluted because polluted water is harmful to fish.
Hatchery Structures
At the inception stages of every hatchery, the structure for the hatcheries must be in place. Constructing the structures for the hatchery such as ponds, storehouses, etc., is one of the foremost steps to be taken.
Hatchery Equipment
You will require the appropriate equipment for your hatchery to function properly. You would have to get the necessary hatchery equipment such as incubator, scale, syringe, bowls, spawning net, blade/scissors, etc., for your farm.
To obtain maximum yield and have a successful catfish hatchery, you would need to have the appropriate equipment for the job. Below are some of the important equipment that you would need;
Incubator:
The fish incubator is used to maintain the fertilized catfish eggs in water until they are hatched to fries. The incubator allows for the circulation of freshwater over the eggs and this enables them to develop with a proper supply of oxygen. This is where the eggs are hatched.
Scale:
The scale is used for weighing the fish intended to be used for hatching if they meet the required weight or size. This is done to know the catfish that tend to hold more matured eggs. The eggs that are stripped from the fish are also weighed. This helps to know the number of fries that you should be expecting.
Ovulating agents and Syringe:
There are ovulating agents such as ovaprim or ovul which the fish meant for hatching are to be injected with. These ovulating agents help to stimulate and also enable reproduction in the catfish. The syringe is used to inject the ovulating agents into the catfish.
Saline Solution:
Milt sac (sperm) is usually gotten from the male broodstock and it is mixed with the eggs gotten from the female broodstock using a saline solution. The saline solution aids the fertility of the milt sac by helping to keep the sperm alive when it is being mixed with the eggs, and it also increases the ease with which the milt douses the stripped eggs.
Scissors or blade:
To get the milt sac out of the male broodstock, it would have to be cut open, and then it would be brought out. The scissors or blade can be used to do this. Also, the milt sac would need to be cut open before mixing it with the saline solution. The scissors or blade will also be used to do this.
Bowl:
After the female catfish has been injected with the ovulating agent, it is isolated in a big bowl and left for some hours before being stripped of the eggs. The bowl is also used for the mixture of the milt sac, saline solution, and eggs.
Towel:
When you want to inject the fish with the ovulating agent, use a moist towel to cover its head. Doing this helps the fish to be calm during the injection process. Also, when you are ready to strip the eggs from the fish, after bringing it out of the water, you should wipe it using a dry towel and then cover its head again using a moist towel.
Spawning Net:
The eggs are spread on the spawning net which is placed over the incubator. If the egg hatches, it will fall through the net and into the incubator while it remains on the net if it doesn’t hatch.
Broodstock
Fertilization is required for the production of eggs in the hatchery. Mature male and female fishes would be required for this fertilization process. The male and female fishes are referred to as the broodstock.
Production
After identifying the broodstock for fertilization, you can then begin production. There are some steps involved in the production process;
- Differentiate the male broodstock from the female broodstock. This is quite easy to do with the matured catfish. The male catfish has an elongated sexual papilla with a red tip for the sexually active ones, while the female has a reddish, swollen genital opening.
- Weigh the selected fish to have an estimate of the eggs the broodstock contains.
- Inject the female broodstock with hormones that would help to induce ovulation. The hormones could either be the pituitary gland which is harvested from the fish or artificial (synthetic) hormones such as ovaprim. The amount of hormone that you’ll inject the fish with will be dependent on the weight of the fish. When injecting the fish, cover its face with a towel and the syringe should be angled towards its tail to help increase the efficiency of the hormone. Then separate the fish after injection for about 12 hours.
- Stripping the injected female for eggs is the next step. After the 12 hours are up, remove it from the water, wipe it dry and then cover its face with a towel then press its stomach gently to strip the eggs into a clean bowl. You can weigh the stripped eggs to have an idea of the fries you are expecting.
- Collection of the milt from the male would also be done. Unlike the female, the male fish will be killed as their stomach would have to be cut open to be able to get the milt sac.
- Mix the milt with a saline solution, and then pour the mixture of the milt and the saline solution evenly into the bowl of stripped eggs. The saline solution helps the motility of the sperm cells and egg fertilization. Then add clean water to the mixture to begin the process of fertilization.
- The eggs will be hatched in the incubator. The spawning net is spread on the incubator and the spawning sponge is spread on the spawning net. The spawning sponge is completely immersed in water but still kept afloat by the spawning net. The mixture of the milt, saline solution, and eggs is then spread on the spawning sponge.
- Check on the incubator after about 24 hours to see if the eggs have hatched. The hatched eggs will go down to the bottom of the incubator while the eggs that didn’t hatch will turn white on the spawning sponge. Take the sponge out if you think the eggs have all hatched.
Hatcheries supply fish farms with fingerlings which they need to be able to produce matured catfish for sale which makes them very important to the catfish farming business. Knowing about this level of importance, if you wish to begin a catfish hatchery, getting it right cannot be overstressed and at Indigoafrica we have professionals that can set up a standard commercial hatchery with our state of the art agricultural machinery.