Skills in the use of fish medicine

After the disease, the food intake of aquatic animals is generally reduced, often wandering alone or climbing onto the shore and among aquatic plants. For the groups of aquatic animals with severe loss of appetite, even if the drugs are mixed in the feed, only some aquatic animals that have not lost their feeding ability can eat the bait, so it is difficult to achieve the goal of comprehensive drug treatment. When using the method of drug bait feeding, the food intake of sick aquatic animals must be fully considered. The author advocates that the bait should be prepared according to the actual food intake of aquatic animals during the disease period.

Bacteria, bacteria, fungi and various parasites may become pathogens of aquatic animals, but there are no drugs that can cure all diseases. Therefore, before using a certain drug to treat the disease, we must first identify the pathogen and make a correct diagnosis of the disease.

At present, there is no effective treatment for viral diseases. Once aquatic animals are infected with virus, their physique and immunity are low, and they are easy to be re-infected by pathogenic bacteria, so antibiotics should be used to treat aquatic animal diseases caused by pathogenic bacteria. We should also pay attention to whether the aquatic animals are systemic infection or local infection, and we should choose different ways of drug administration.

All kinds of diseases caused by parasites, such as protozoa, large trematodes and crustaceans parasitic on the body surface, can achieve good results by using the whole pool sprinkling method, and the drug bath method can be used to eliminate protozoa when the seedlings are released. However, for the parasites in the digestive tract of aquatic animals, such as echinocephalus, nematodes, trematodes and other internal parasites, we must use bait feeding. It is possible to obtain a more ideal therapeutic effect.

The medicine which is soluble in water or after a small amount of solvent treatment can be used as bait feeding, medicine bath and whole pool sprinkling method. At present, the commonly used dosage forms are powder, water, granules, as well as tablets, microcapsules and injections: in the types of aquatic drugs, powder occupies the main position, and the variety of preparations is also rich. Aqueous agents are also convenient for aquatic drug delivery, such as some common insecticides (pyrethroids), disinfectants (sodium hypochlorite, unitary chlorine dioxide, formalin, peracetic acid) and other liquid preparations. Because of its slow effect, long action time and less irritation to aquatic animals, tablets can be used when disinfecting the bottom of the pool and if the use of powder will stimulate aquatic animals.

Advocate the use of microecological agents, for the prevention and treatment of aquatic animal diseases, the author thinks that it is not necessary to kill all pathogens, but requires them to be at a disadvantage in quantity, and to cultivate beneficial bacteria vigorously. Use beneficial bacteria or neutral bacteria or even some inactive pathogens to compete with harmful pathogens, so as to inhibit their growth and reproduction. When selecting microecological agents, we should pay attention to the following conditions: (1) it can symbiosis with the host and should be non-pathogenic and non-toxic to the host. (2) it can reproduce rapidly and form the dominant population. (3) the acid-producing ability of the strain is strong. (4) it can produce antibiotics, which makes it easy to win in the interspecific competition, so as to prevent the colonization and reproduction of pathogenic bacteria. (5) it is easy to maintain sufficient bacteria number and vitality in the process of preparation. (6) easy to be used in combination with other bacteria.