(2) Microecological preparation Microecological preparation is a preparation under the guidance of microecological theory, which uses live beneficial microorganisms or their growth-promoting substances beneficial to the host to adjust the microecological balance in vivo, improve the utilization rate of animal feed and promote animal growth.
(3) Chinese herbal medicine feed additives (or plant extracts) Chinese herbal medicine feed additives (or plant extracts) are pure natural feed additives based on the theories of physical properties, tastes and interrelationships of traditional natural Chinese herbal medicines, supplemented by the theories and technologies of feed and feed industry. It has the following advantages: ① nonspecific antibacterial effect, which can not only directly inhibit bacteria and sterilize without drug resistance, but also regulate and improve the immunity of the body: ② low residue in livestock and poultry; ③ It has multiple nutrients and bioactive substances, and has dual functions of medicine and nutrition.
(4) Single-cell protein is the general name of single-cell biological protein artificially cultivated by biotechnology or cell protein of simple multicellular organism, which mainly includes yeast, non-pathogenic bacteria, mold and algae. Among them, feed yeast has the fastest development. In addition, there is a product type of feed yeast-yeast culture, which refers to yeast cells and their substrates and metabolites, mainly with enzymes secreted outside the cells and unknown growth factors in the culture as their efficacy. Feed yeast contains many digestive enzymes needed by animals, and is rich in vitamins, crude protein and amino acids, which plays a particularly significant role in livestock and poultry breeding.