Probiotics, also known as probiotics, probiotics, probiotics and living bacteria preparations, refer to the biological agents or living bacteria preparations that are beneficial to animals by special processes such as cultivation, rejuvenation, fermentation, embedding and drying under the guidance of Microecology theory. Some of them also contain their metabolites or (and) growth promoting factors added with beneficial bacteria It can maintain the micro ecological balance of the host, adjust the micro ecological imbalance and improve the health level of the host. It plays an important role in the establishment of a good aquatic micro ecological environment (including the micro ecological environment in vitro and in vivo) for healthy aquaculture.
According to different standards, probiotics can be divided into:
(1) According to the purpose of use, there are growth promoters, immune promoters and water quality improvers.
(2) According to different strains, there are Bacillus preparations, lactic acid bacteria preparations, yeast preparations, photosynthetic bacteria preparations, nitrifying bacteria preparations, etc.
(3) According to the species composition, there are single preparation and compound preparation. Compound preparation can adapt to various conditions and hosts, and has the best effect, which is the current development trend.
(4) According to the material composition, there are probiotics, prebiotics and synbiotics.
Probiotics: refers to a kind of bioactive agents which are usually separated from the normal flora in automatic objects. It can play a biological competitive rejection role through the digestive tract of animals, help to establish intestinal microflora beneficial to the host, so as to prevent diseases, promote growth and improve immunity.
Prebiotics: refers to oligosaccharides and other organic substances that are not digested and absorbed by the host, but can selectively promote the metabolism and proliferation of beneficial bacteria such as bifidobacteria in animals, so as to improve animal health.
Synbiotics: it is a biological preparation combining probiotics and prebiotics, which can play the role of probiotics and prebiotics at the same time.
(5) According to different dosage forms, there are liquid dosage forms, solid dosage forms and semi-solid dosage forms