FISH FEEDS

In all fish farms, the largest most single operating cost is FEEDS (almost 50%) and it is in the interest of the farmer to get a good return on this investment in terms of fish weight gain.

     An experienced feeder that is able to optimize consumption without excessive feed wastage is invaluable to a catfish producer. Feeding the most suitable feed in a manner that result in fast growth and efficient feed conversion result in more efficient production in increased profits. Uneaten feed cost the producer directly in decreased profits and indirectly through degradation of water quality. About ½ of the variable production cost in catfish production is feed, so a wise farmer reduces the overall cost of production by using the most appropriate feed and feeding it in the manner that most efficiently produces fish.

The extent to which a food is utilized by temperature, quietness, amount of darkness, space available for swimming, and culture practice vis-à-vis the availability of water, the presence of disease (due to overcrowding, weather change, disturbance aggression due to mixed stocking) and the age (this is with respect to people who buy too small a size of fish only to drastically) and genetic constitution of the fish (I do not think of anyone who knows of a better breed who will jettison the idea for a brand with less growth potential).

However, the most basic factor is the composition of the food and how closely it matches the fish’s nutritional requirement.

It is possible to compound diet from various ingredients found in local feed stuffs that will satisfy these requirements. The proportions of these ingredients within the diet must be adjusted so that the totals of the PROTEINS, CARBOHYDRATES, FIBRES, VITAMINS AND MINERALS fall within the expected range. Feed formulation therefore requires a great deal of patience.

N.B FISH MEAL (72% Danish, 65% Russians or some local variety) must be included at not less than 8% in all diets.

   Evaluation of food for its economics benefit is based on calculating a food conversion ratio. This is the amount of feed in kg required to produce 1kg of fish. A feed conversion ratio of 1.1 means that for each kg of food fed, a kg of fish produced.

   High quality food gives a lower ratio than poor quality food. The cost of feeding fish must be offset against price expected for fish at harvest. Since feeds are responsible for about 50% of operating cost, it does not need to be so expensive if a lower feed conversion ratio is acceptable by the fish using locally available materials.

   Should any of the participants need a customized low formulation for his own domain, it can be obtained from us for a token fee.

 FORMULATED FEEDS.

             Raw Materials: Below are few of the common feeds which are often blended to        

             Prepare fish rations.

             Some might not be available within your domain locally but you can look up to  

             table 1   to identify close alternative source of equally good nutrition.

Fish meal: this is produced by cooking fish, rolling and pressing to remove water and oil, and then drying. Species such as Anchovy and mainhaden make excellent fish meals that are high in the 10 essential amino acids (this must be present in the food composition or else the body protein formulation comes to a halt. The most common brands in Nigeria local fish meal (50% protein). It is sold for N250, N90 per kilo respectively. The Nigeria versions are actually Fish Offals produced by cooking waste products and pressing to remove water and oil and subsequent drying. It is a good source of calcium and phosphorus.

1.        Soya Bean Meal: this is a major protein of commercial catfish feed in the United State and also here in Nigeria. It is high in essential amino acids and it is both digestible and palatable. This is not the same human being eat but the ones that have been chemically treated by solvent extraction and roasted to inactivate the –nutritional factor. It is sold at M36 per kilo while the full soya goes for N38 per kilo.

2.        Groundnut Cake (GNC): This can be used to replace a small part of the soya bean in feeds being cheaper at N26 per kilo but it has a low lysine content (an essential amino acid) and is also susceptible to contamination with the mould Aspergitus flavus which produces Aflatoxins. NEVER USE MOULDY GROUNDNUT CAKE OR OTHER MOULDY FOODS.

3.          Maize: In form of offal can be used as a major energy source in feeds. It is worth-while if it can be cooked or the cooking during the pelleting process will improve its digestibility. Maize can form up to 30% of the diet.

4.     Wheat Offal: This is a by-product of milling process. The offal has a high amino acid contents.

5.     Bone meal and Crushed shells: These are dry rendered animal bones and periwinkle shells. It has high ash content and it is the major source of calcium and phosphorus without which fish will be retarded in growth. It should not be more than 10% of diet.

6.     Vitamins: Proprietary vitamins are available at poultry stores. Fish use essentially the same vitamin brand as chickens. So buy the broiler or grower premix for healthy growth, this prevents the occurrence of deficiency disease problems.

7.     Growth Boosters: In form of amino acids can also be added to enhance performance.

COMPOSITION OF SOMEUSEFUL INGREDIENTS

Table 2a on the back page shows the composition of some useful ingredients at by using approximate analysis (%dry weight).

FEED FORMULATION & MANUFACTURE

Catfish feeds are generally based on fixed formulas with little use of the list cost approach to feed formulation used with other animal industries. This is because of lack of knowledge of the nutrient levels that result in maximum profit as opposed to levels that maximize weight gain. The very few feed mills that attend to farmers do not have the capacity to store large number of different ingredients and the logistics of obtaining assortment of food stuffs on a timely basis is lacking.

Table 2a how my inference based on years of personal research and interaction with farmers and books. The restriction percentages serve as the do’s and don’ts for the farmer who desire result and beside it is a local interpretation or we call it the nitty gritty of fish feeds.