Safina Musa, a research scientist and Station Coordinator at Kenya Marine and Fisheries Research Institute Aquaculture Centre, Sangoro in Kisumu explains what is a quality fish feed, the right feeding regime and how farmers can benefit from the government institution.
Lake shrimps (ochong’a), an important ingredient in the making of fish feeds, has become hard to come by.What are the alternative sources of protein for fish feed formulation?
In aquaculture, feeds account for 60 per cent of the production costs. The most expensive ingredient in the diet of the fish is the animal protein component. When making the fish feed diet, we mix both the animal and plant protein.
The animal protein is most preferred to the plant protein because it’s palatable and nutrients are readily available to the fish. There are alternative dietary animal component that farmers or fish feeds companies can use such as prepared blood meal from slaughterhouses, feathers, crickets, worms, black soldier fly and fine ground bone meal.
However, there is always caution for total replacement of fish meal, you should replace but not above 50 per cent of the fish diet.
What role does technology play in the fish feeds industry?
There are softwares that farmers and fish feed manufacturers can use. One can use WinMIX-Feed for feeds formulation. It is user friendly though expensive. The user keys in the ingredients and their crude protein content then the software helps in balancing and mixing of the quantity of the ingredient to generate the end crude protein level needed for the fish, according the size and growth level.
For example, when formulating feeds for fish fries, the protein level should about 40 to 45 per cent for growth.
What makes a quality fish feed?
The nutritional and physical characteristic of fish feeds is essential. For nutrition value, the feeds should have crude protein, lipids, niacin, vitamins and enzymes. A high quality feed should be easily consumed and digested by the fish.
The fish pellet should have uniform colour, be free from fines (dust like feeds) and firm with water stability of at least 30 minutes.
The pellet should have uniform size, usually they come in sizes of 1mm to 6mm. It should also be a quarter the gap of the mouth of the fish. If the pellet is too big, the fish will not consume it. The feed should also be palatable with an aroma of fish meal. Avoid moldy pellets because they cause deadly fungal diseases known as aflatoxicosis, which can wipe out the enter fish stock in a pond or cage.
What is a good fish feeding regime?
Most farmers don’t know when to feed or when not to feed the fish. Weather patterns affect the feeding of the fish. On a cloudy weather, the waters are usually cold, thus, the fish will not feed. If possible, have water quality kit or thermometer to measure the temperature before feeding. If the water temperature is below 22 degree Celsius, do not feed your fish.
If the dissolve oxygen is below 5mg per litre, that already affects the fish. At times the fish will not respond well to feeds due to poor water quality and diseases. Don’t feed the fish before sampling, it can lead to stress and mortality. Learn to feed the fish to reduce the chances of overfeeding or underfeeding.
Feeding frequency depends on the stage of the fish, whether they are fries, fingerlings, growers or brooders. Fries have small stomach and their metabolic rate is high hence they feed after every two hours. The frequency of feeding is higher in small fish than in growers’ stage.
As KMFRI, how can fish farmers benefit from you?
Our core mandate is research, operating hatchery units, doing tests on fish and commercial feed production. We sell quality mashes at Sh120 per kilo and pellets at Sh80 per kilo. We have outlets in Kisumu, Rongo and Oyugis.