Fish Breeds and Fingerlings SS2 Livestock Farming Lesson Note

The Stars of Nigerian Fish Farming

In Nigeria, if you visit a fish farm, you are almost 90% likely to see one of two types of fish. Just like we have different breeds of cows or chickens, we have specific fish that grow well in our climate.

1. The African Catfish (Clarias gariepinus)

This is the “King” of Nigerian aquaculture.

• Why farmers love it: It is very “tough.” It can breathe air directly from the surface, so it doesn’t die easily if the water is a bit dirty.
• Growth: It grows very fast and can get very big (table size) in 4 to 6 months.
• Market: Nigerians love catfish for “Point and Kill,” pepper soup, and dried fish.

2. Tilapia (Oreochromis niloticus)

This is the “Queen” of the ponds.

• Why farmers love it: It is very tasty and feeds mostly on plants and tiny water organisms, which makes it cheaper to feed.
• The Problem: Tilapia breeds too fast. If you put a male and female together, they will fill the pond with tiny babies, and none of them will grow big because they are competing for food.
• Solution: Most farmers now grow only male Tilapia (Monosex) so they can focus on growing big instead of making babies.

Other Fish Species We Farm

While Catfish and Tilapia are common, some farmers also keep these:

1. Heterobranchus: This is a cousin to the catfish. It grows even bigger than the regular catfish but takes a bit more time.
2. Carp: These are not as common but are farmed in some parts of the country. They are very bony but have a nice flavor.
3. Heteroclarias (The Hybrid): This is a “cross-breed” between Clarias and Heterobranchus. It’s like a “super fish” because it combines the fast growth of one and the toughness of the other.

Introduction to Fingerling Production

Where do the fish come from? You don’t just wait for them to appear in the pond. You have to produce them or buy them from a Hatchery.

The Life Stages of a Fish:

1. Egg: The starting point after spawning.
2. Fry: Tiny babies that have just hatched. They look like little wiggling threads.
3. Fingerling: This is the stage most farmers buy. They are about the size of a human finger (5–10cm).
4. Juvenile: Older than fingerlings, about the size of a pencil. They are stronger and survive better in big ponds.

Why produce fingerlings? It is a very profitable business. One mother fish can lay thousands of eggs at once!

How We Get Fish to Lay Eggs (Induced Breeding)

In the wild, fish wait for the rainy season to lay eggs. On a farm, we can’t wait for the rain! We use a method called Induced Breeding.

1. Selecting Parents (Broodstock): We pick a healthy “Papa” fish and a “Mama” fish that is “ripe” (her belly is swollen with eggs).
2. The Injection: We give the female fish a hormone injection (like Pituitary extract or synthetic hormones). This “tricks” her body into thinking it’s time to lay eggs.
3. Stripping: After some hours, the farmer gently presses the female’s belly to collect the eggs in a bowl.
4. Fertilization: We kill the male fish (usually) to get its “milt” (sperm) and mix it with the eggs using a feather or a clean plastic spoon.
5. Incubation: The fertilized eggs are put in a tank with constant running water. In about 24–30 hours, they hatch into fry!

Taking Care of the Babies (Nursing)

The first few weeks are the most dangerous for fish. If you don’t take care of the fry, they will all die.

• Feeding: Tiny babies cannot eat regular fish pellets. We feed them Artemia (tiny water shrimps) or very fine powder feed.
• Clean Water: Their “nursery” must be very clean. Any small disease can kill the whole batch.
• Sorting (Grading): This is very important! Some babies grow faster than others. Catfish are cannibals—the big ones will eat the small ones! Farmers must use a “Grader” (a tray with holes) to separate the big ones from the small ones.

Student Checklist:

• Can you identify a catfish and a tilapia?
• Do you know why we inject the female fish?
• Can you explain why we “grade” or sort fingerlings?

Note to Students: > Fingerling production is like a “hospital” for fish. It requires a lot of patience, clean hands, and very close observation. One mistake with the water temperature can ruin a whole month’s work!