Tannin is a zootechnical additive, indicated as a performance enhancer to be used in the feeding of broilers (initial and fattening), weaned piglets in the nursery phase, crustaceans and fish (fattening) and for lactating cows. coi đá gà thomo c1 It is a natural, phytogenic additive, rich in polyphenols, which can be used in animal nutrition as a performance enhancer.