In addition, the amounts of supplemental phosphorus and trace minerals have been reduced. Practical nutrition studies also have led to a reduction in the level of certain vitamins in the vitamin premix, while others have been completely eliminated. Ingredient composition of commercial catfish feed containing 28 percent or 32 percent protein.ī Commercial mix that meets or exceeds allĬ Sprayed on finished feed pellet to reduce Robinson, catfish feeds, Table 1 Ingredient An all-plant protein diet has yet to be adopted by the industry but some producers are using diets that contain 2 percent or less animal protein. In fact, a properly balanced diet based on soybean meal and corn can be used to meet the nutritional requirements of catfish and it is highly palatable. Fishmeal is generally replaced by a blend of meat and bone and blood meals however, other animal protein sources can be used. The ingredient composition of a typical commercial catfish feed for growing food fish is given in Table 1. Today 28 percent to 32 percent protein diets are commonplace, and they rarely contain more than 4 percent marine fishmeal and some do not contain any. Reducing diet costĮarly catfish feeds used for raising food fish often contained 35 percent or more protein and 12 percent to15 percent marine fish meal.
For example, dietary protein level can be reduced, and the industry is less dependent on marine fishmeal or on animal proteins in general. Enough practical information has been accumulated to give catfish nutritionists some flexibility in meeting the catfish’s nutrient requirements.
Because of this difference and since feed cost represents about onehalf of the variable costs associated with raising catfish, catfish nutrition research over the last 10 years or so has concentrated largely on practical nutrient requirements. Most commercial catfish feeds have been formulated based on nutrient requirements determined with young catfish raised under controlled environments in the laboratory, which is much different from the environment in which catfish are raised commercially. Importance of practical nutrition studies Presently there are nine catfish feed mills that supply some 630,000 metric tons of catfish feed annually to the industry. Today catfish are fed extruded (floating) feeds that are blended specifically to meet all their nutritional needs. In addition, it was recognized that steam-pelleted feeds were unsatisfactory primarily because of their poor stability in water, and since they sank rapidly, it was difficult to judge fish feeding activity. Supplemental feeds were adequate when fish production was relatively low, but as production intensified it became apparent that a nutritionally complete feed was necessary for the continued growth of the industry. Thus, they served to supplement whatever nutrients the fish could derive from the pond environment. These feeds were steam-pelleted (sinking) feeds that primarily provided protein and energy but were generally deficient in micro-nutrients, such as vitamins, trace minerals and essential fats. As a result, early catfish feeds were typically formulated from nutritional data that existed for trout and poultry. Information on the nutrition of catfish was practically nonexistent in the late 1950s and early 1960s when catfish farming first started.
Feed composition, feeding regimes can vary from farm to farm Nutritional advances have greatly reduced the cost and improved the effiiency of channel catfish diets.
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