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Bioflavonoids that act as natural antioxidants, i.e. scavengers of active oxygen radicals that may adversely affect the health of fish.
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Probiotics,, the first line of defense against intestinal disease, are healthpromoting bacterial organisms that improve the microbalance by selectively suppressing harmful bacteria in the intestine.
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Prebiotics refer to a group of natural sugars such as oligosaccharides that are resistant to digestion by fish but can be utilized exclusively by specific probiotic organisms, allowing them to compete with and exclude pathogens in the gut (called ‘competitive exclusion’). Thus, prebiotics are nutrients for probiotic organisms.
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Immunostimulants promote the macrophage (= defence) system to eliminate pathogens in the bloodstream.
Additional claims for ‘neutraceuticals’ indicate that the use of functional feeds will aid in the control of pathogenic bacterial and fungal growth, as well as reducing the digestive problems that occur commonly after antibiotic treatment or prolonged stresses (de Wet, 2002). From a practical point of view, there appears to be benefit in some of these alternate approaches to the control of disease, not only in fish, but also in other classes of animals, including humans (Fuller, 1989). Over time, such viable techniques could supplant many of the tons of antibiotics used today in the combined aquacultural and other livestock industries. Such replacement could reduce significantly, the number and species of antibiotic-resistant bacteria in the health of humans and livestock. Some examples of ‘neutraceuticals’ are listed herewith. i) Probiotics Alternative approaches to the use of antibiotics in the treatment and/or prevention of diseases affecting a variety of livestock, including fish, as well as
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