MANAGEMENT OF TABLE SIZES (Catfish)

MANAGEMENT OF TABLE SIZES (Catfish)

This is the rearing of juvenile fish to table size usually weighing 700gm – 1kg on the average, 1.5kg and above. This is highly capital intensive ventures as it requires at least the following:

•         Production tank (concrete, earthen, plastic, wooden)

•         Feed for feeding the fish to table size

•         Enough or adequate water availability

•         Electricity/generator

•         Good quality fingerlings/juvenile

Production tank: This is where the fish shall be cultured to maturity; these can be made with concrete tank, plastic tank, wooden tank, fiber tank, earthen pond. A 6ft X 15ft x 4ft concrete tank can successfully raise a 1000 fish to maturity. A connection of 6 to 12 tanks of the same dimension, connected through the individual outlets, water are channel to the concrete tank through pressure pipe from overhead waters tank or directly from a well, borehole etc.

WATER QUALITY

            Water quality is the first most important limiting factor in pond fish production. It is also the most difficult production factor to understand, predict and manage. Water is not just where the fish live. Its quality affects feed efficiency, growth rates, the fish’s health and survival. Most fish kills, disease outbreaks, poor growth, poor feed conversion efficiency and similar management problems are directly related to poor water quality.

Water quality refers to anything in the water, be it physical, chemical or biological that affects the production of fish. The objective of pond management, is to manage the water quality, so as to provide a relatively stress free environment that meets the physical, chemical and biological standards for the fishes normal health and production performance. Water in adequate quantity is a singular most important factors must be provided, if possible continuously I mean continuous inlet and outlets system, where water goes out and fresh water comes into the pond. This help to extremely reduce the organic loads of the fish pond. Alternatively, the tank can be drained every day, 2 times weekly, weekly as the case indicate, and also the availability of water. However, before any catfish farming operation, good quality water in adequate quantity is must pre-requisite. Water parameter should be monitor for optimum performance.

Within a pond, water quality is a product of:

•         The quality of water at the water sources,

•         The quality of the pond soils and immediate environment,

•         Production technology and management procedures employed, notably those associated with feeding, the maintenance of adequate dissolved oxygen as well as any other chemicals or inputs applied.

FEEDING TABLE SUGGESTING FOR CATFISH

Fish size (grams)	Feeding Level (% food of body weight/day)	Feed size (mm)
1 – 3	15 – 11	0.8 – 1.2
3 -5	11 – 9.5	1.2 – 1.5
5 – 10	9.5 – 7.5	2
10 – 30	5.5 – 4.5	2
50 – 70	4.5 – 4	3
70 – 100	4 – 3.5	3
100 – 200	3.5 – 3	4.5
200 – 300	2.5 – 6	4.5
300 – 400	2.6 2.3	6
400 – 500	2.3 – 2,1	6
500 – 600	2.1 1.9	6
600 – 800	1.9 – 16	10
800 – 1000	1.6 – 1.4	10
1000 – 1300	1.6 – 1.4	10

Feeding Time for Fish

1. The feeding frequency is the number of times fish in a pond are fed in a day. The feeding frequency affects the efficiency of feed utilization (i.e. the FCR) so it is important to establish the optimal frequency of feeding so as to attain the best possible (optimal) FCR and uniform sizes. The following should be taken into account, when deciding how frequently fish should be fed each day:
2. For optimum growth and feed conversion, each feeding should be about 1% body weight. However, it is expensive in terms of labour to feed 4 or 5 times per day. In grow-out ponds, feeding 2 or 3 times a day is adequate.
3. Slow broadcasting is the recommended way for administering pellets to catfish grow-out ponds. Do not trickle the feed in.
4. Proper feeding frequencies reduce starvation and result into more uniform sizes.
5. Juvenile catfish need to be fed more frequently than adults, because they have higher metabolic rates and their stomachs are too small to hold all the feed they require for a day.
6. Catfish from 400g can be fed once a day, because at this size the stomach can hold enough food for the day. At this stage, feeding all the fish at the same time once a day, results into more uniform growth rates because the greedy ones will still be full when there is still food around in the pond. This provides a good chance for the smaller fish to come and feed, hence, they also grow.
7. The feed administered as a meal should be consumed within the first 15 minutes of the feeding if you are using floating feed. If it is not, reduce the amount given to match how much can actually be consumed. This is a bit tricky with sinking feed but it is possible.

The fish’s feeding response depends on the:

1. Suitability of the feed. The feed’s appearance, smell, texture/feel and taste also influence the fish’s appetite. The more palatable the feed is, the better the feed response should be
2. Culture (Water) Environment: The most important water quality parameters that affect feeding response in ponds are water temperature and dissolved oxygen. The warmer the water and more dissolved oxygen it has, the more active fish will be and the better their feed consumption and FCR.
3. Other Stressors, such as pollutants in water, other water quality variables (notably of ammonia and pH), handling and social interactions also affect the fish’s appetite. When fish are stressed, their appetite drops quickly.

When Not to Feed Fish

The Feeding Response is Poor: When the fish show a poor feeding response, it is normally for a reason. The water quality may have changed. For example, on a cold wet day, the pond water temperature may have dropped. Therefore, do not add more food than the fish are interested in consuming. Rather, find out the cause of the poor response and if it is due to something you can address, then correct it.
When Feeling Unwell: When fish are sick, they go off feed. If you insist on feeding them, they still will not eat. The feed administered will instead accumulate at the bottom of the pond, and cause the water quality to drop. No positive returns accrue from wasted feed. Instead losses accrue due to reduced water quality, higher FCRs and the lost income from the wasted feed.
At least Two Days before Harvest and Transportation: This is to allow them to empty their guts before harvest and Fish should be fed 2/3 times daily between 8am. in the morning. 2pm in the afternoon and 6pm in the evening. Not that frequent feeding result to frequent change of pond water.  Frequent feeding also helps fish growth. A pelleted feed is specially designed for feeding fish. It weighs between 2mm and 6mm. (sinking or floating).