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How Farmers Can Make More Money in Catfish Farming: Part 2

30 March 2015

The level of success we get in catfish farming is usually tied to the level of management practices we decide to put in place in conjuction with the level of efficiency we achieve from our culture systems, writes Lanre Ogunsina, Fish Unlimited. Part 2 and 3 continue to look at why consuming more feed does not always lead to bigger fish and how farmers must master the art of fish farming.

For Part 1, click here.

I calmed Farmer B down and I showed him the feeding records of farmer A. We both sat down and compared the records.

In month 1, Farmer A's Fishes consumed 101kg of feed while his own fish consumed 87kg of feed.

By month 2, his fish consumed 292kg of feed while Farmer A's fish consumed 298kg.

By the 3rd month, the quantity of feed his own fish consumed was 617kg as compared to the 540kg farmer A's fish consumed.

From the records also, we both saw that at the end of the first month, Farmer A's fish averaged 86g in weight while his own fishes weighed just 51g on the average.

At the end of month 2 the weight of his fish on the average was 173g while that of farmer A was 245g.

When Farmer A was happy at the end of the 3rd month because his fish were averaging 520g, Farmer B's fish were weighing just 408g on the average.

By month 4, Farmer A's fish were just 10g short of 1kg on the average while Farmer B's fish were weighing on the average 883g.

The Cumulative feed consumed by Farmer A's fish from Month 1 to 4 is 1833kg while Farmer B's fish have cumulatively consumed from month 1 to month 4 a total of 2245kg of feed.

From the look on Farmer B's face, the question was, what am I not getting right?

Not only have his fish consumed more feed, they were still less in weight.

I further went on to explain to him that the feeding dynamics of the African catfish in ponds is very interesting. They love exhibiting territorial behaviors; especially when they are not densely stocked.

These territorial traits are further amplified in their behavior when some are bigger than others. The bigger ones not only usually get to the food first, they often at times prevent the smaller ones from feeding well.

Some fish seeds which are called jumpers or shooters usually grow at geometric rates while others grow at arithmetic rates.

For the breeder that is diligent enough, the best thing to do is to carefully remove shooters and give farmers fish of the same size.

The African catfish can eat as much as 3 to 5% of its body weight provided pond water is okay.

Farmer A fed his fishes about 2.5 to 3% of their body weight within the period of the 4 months.

Part 3

After I shared this series of information with Farmer B, he became calm as i anticipated. It was quite evident that there were a lot of things he was not doing right.

He had money to feed his fish quite all right but the quantity of feed he had used was more than what he ought to have used.

It was also evident that Farmer A's fish had performed better in weight gain and feed conversion.

I checked my wrist watch and it was time for me to feed the fish in the tanks. I invited Farmer B into my catfish nursery and encouraged him to observe fish inside the nursery tanks. I was using 1200 liters plastic blue tanks to raise African catfish juveniles.

As I fed the 6 weeks old fish seeds, Farmer B became more and curious. He quickly noticed that I kept the tanks stocked at premium. He asked me why and I told him it was because of the feeding nature of the fish. Catfish feed more in a stocking population that encourages competition.

As i continued feeding the fish, I told him that there is so much we need to genuinely understand as fish farmers concerning the eating habits of organisms. From my own experience, taking cue from the African catfish, every organism, tends to want to eat more mostly in an atmosphere of competition.

The reason is simple-there are so many hungry mouths waiting to devour whatever food left uneaten.

As fish farmers, our line of business is deep, dynamic and creative. There is a science part to fish farming and so is an art part. 

Part of what the science part does is to give us the knowledge of what to do as the various variables of the water chemistry in pond water changes. 

Changes do come to the pond water when there is overfeeding or bad management. The dissolved oxygen in the water depreciates as the nitrate and nitrite levels in the water go up.

The science part gives the average farmer good insight into what to do as pond water gets stale and is not changed as frequently as it should be. 

The art part however gets developed by the sensitive farmer over time. A sensitive farmer can tell the size of the fish as well as the possible weight of his fish by just looking at the size of the mouth of the fish. The art part gives the farmer insight into the unrevealed life of the fish.

A knowledgeable farmer looks out for various things every-time he gets to his farm. 

The unusual presence of numerous air bubbles on pond surfaces shows to the wise farmer that something is wrong. Excessive bubbles shows the concentration of gases inside pond water.

It was evident that Farmer A had mastered the science and art part of fish farming. The art part encourages the development of the farmer's sense of smell and sight. The farmer should be able to smell any form of foulness in the pond. He should also be able to positively guess if something is wrong by mere looking at the pond water colouration.

Over time, a farmer should be able to determine the total quantity of feed he should give to his fishes every day of every month during the culture cycle. 

Most fish farmers are still in the habit of guessing the quantity of feed they should give to their fish. In big farms with many ponds and many workers, a lot of human errors are committed.

While one worker believes that the fish in the ponds should be satisfied with 1.36kg of feed given to 2500 on morning of day 10, another worker might believe that 136kg of feed is way below what the fish to consume to satiation.

It therefore becomes important that good feeding standards be adopted for fishes in every pond. Farmer A seems to have mastered a good feeding strategy which really has worked for him.

I told Farmer B that he should not be ashamed to ask Farmer A the technique he seems to have adopted in feeding his fish.

Farmer B thought for a while. I encouraged him that it might not be a bad idea if we both go to Farmer A the following day and share in his secrets of fish feeding.

Right inside my hatchery, i called Farmer A and I told him we will be happy if he could let us into what he knew concerning fish feeding and management. Farmer A was happy and he said he would let me know when he gets to farm the following day. 

Further Reading

Go to Part 1 of this article by clicking here.

March 2015

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