Feed additives are small or trace substances added during feed processing, production, and use. Its role is to supplement the nutrition of livestock and poultry, promote animal growth, improve feed utilization, improve animal product quality, and protect animal health. At present, there are a wide variety of feed additives on the market (in our city there are nearly one hundred species), and fish farmers tend to mix beads, and the majority of farmers are on the outside to determine what kind of feed additives to buy, then, when buying, should pay attention to what problems? ? 1, to see if there is a product quality inspection certificate and quality standards. Do not purchase without certificate and quality standards. 2, to see if there is a product approval number and production license number. The format of the approval number is: Feeding word .... The approval document number format of the drug feed additive is: drug add word .... The approval document number is valid for 5 years. If it exceeds the time limit, do not purchase it. 3, see the label. The label shall indicate the product name, raw material composition, product component analysis guarantee value, net weight, production date, shelf life, factory name, site, product standard code, use method and precautions in Chinese or applicable symbols. If there is no label or the label is incomplete, it shall be an unqualified product. Do not purchase it. 4. The imported feed additive shall have the import registration license number registered by the competent administrative department of agriculture under the State Council. The validity period is 5 years. The product must indicate the country of origin and the name of the country of origin in Chinese. Products without the Chinese mark are unqualified products and should not be purchased. 5, should try to reach a good reputation, quality assurance, professional and technical personnel of the store to buy, so that when in doubt consult a professional to get the necessary guidance.