Feed additive and production method thereof

The invention discloses a feed additive and a production method thereof. The feed additive comprises the following ingredients in parts by weight: 700g-1000g of crop-residue-derived carbon, 80g-100g of pyroligneous liquor, 1g-5g of radix astragali, 2g-8g of ganoderma lucidum, 2g-8g of prepared rhizomes of rehmannia, 3g-9g of cyrtomium rhizomes, 3g-9g of rhizoma Menispermi and 5g-10g of lonicera japonica. The feed additive provided by the invention is a green and ecological product; through a reasonable proportioning, the additive can promote the growth of a large quantity of probiotics inside animal bodies, generate protein of high immunity, stabilize intestinal balance, enhance organism immunity and reduce diarrhea and intestinal diseases; and meanwhile, through fermentation in vivo, the additive can promote the secretion of various kinds of digestive enzymes, cellulose, etc., promote the conversion of protein to small peptides, improve a digestive function, drive organs to quickly absorb high-quality nutrie