Hangtai Aquarium: what will happen if you give a heavy dose to sick fish?

Many breeders of ornamental fish do not recommend giving medicine when the fish is sick, thinking that it is one-third of the poison. In fact, the editor thinks that we are just worried about not being able to control the dosage or not being able to diagnose the cause of the disease by giving the wrong medicine. As for how to diagnose fish disease, the article updated by the editor some time ago has said that today we will talk about the choice of the amount and properties of medicine.

Fish medicine refers to substances (including drug feed additives) that are used to prevent, treat and diagnose diseases of ornamental fish or purposefully regulate the physiological function of ornamental fish. it mainly includes antimicrobial drugs, anti-parasite drugs, microecological products, Chinese herbal medicine, external insecticides, disinfectants, nutritional agents and metabolic improvers and environmental improvers. It belongs to the category of aquatic veterinary drugs, which not only has the common characteristics of veterinary drugs (for example, it can act directly on fish), but also has the particularity of the application objects in the aquatic ecological environment, the different application methods and the characteristics that the efficacy is more easily affected by the environment. Therefore, the drugs for disease prevention and treatment and improving the aquaculture environment have the characteristics of the aquaculture environment.

The basic function of ornamental fish medicine is mainly used to kill and inhibit the pathogens that cause disease. The ideal fish medicine should have no obvious toxicity to fish, but it can inhibit its growth, development and reproduction by interfering with the metabolism of pathogens, so as to give full play to the disease function of ornamental fish and achieve the purpose of eliminating and eliminating pathogens.

(1) preventive effect

In aquaculture water bodies (including indoor ornamental fish tanks and aquarium tanks and outdoor large area breeding ponds), various pathogens may exist at any time, but only when these pathogens reach a certain pathogenic amount can fish get sick. If lower doses of drugs are used as early as possible to prevent, kill or inhibit the reproduction and growth of pathogens before these pathogens reach the number of pathogens, ornamental fish will not get sick.

(2) Therapeutic effect.

After the disease of ornamental fish, it is necessary to make a timely scientific diagnosis and use the standard dose, which can better kill and inhibit the growth and reproduction of pathogens, so as to achieve the purpose of treatment. The therapeutic effects of ornamental fish disease can be divided into two types:

One is the treatment of cause, that is, the treatment of eliminating the causes of the disease, which is also called a permanent cure, for example, Chinese anchovy can be directly killed by topical drugs.

The second is symptomatic treatment, that is, it is treated by improving some symptoms of the disease, which is also called palliative. For example, externally used bactericides such as bleach can be used to treat enteritis, but it can only kill pathogens in the water and on the surface of fish, alleviate some symptoms, and cannot be completely cured. It must be thoroughly cured with internal administration of germicidal drugs.

The drug species of ornamental fish sold on the market work in different culture water bodies and different culture objects. Its effect is often affected by drugs, fish, diseases, pathogens and environmental factors.

The effects of ornamental fish drugs are closely related to their physical and chemical properties, because they can affect the absorption and metabolism of drugs. For example, heavy metal salts are easy to react chemically with body proteins to precipitate them, so they can stimulate, converge or corrode; p-aminobenzoic acid is a growth substance of some bacteria, sulfonamides are similar to their chemical structures. can produce competitive inhibition, and show its structural effect. Of course, the different manufacturing process of the drug can also affect the effect of the drug. For example, the effect of the drug is also different with different crushing fineness, mixing uniformity, production temperature and so on.

The dose of the drug refers to the dose that produces a certain response to the fish when it is administered, usually the dosage for the prevention and treatment of diseases. Because the drug must have a certain dose to be absorbed by the body before it can reach a certain drug concentration and the drug effect can appear. If the dose is too small to obtain an effective concentration in the body, the drug will not play its effective role. However, if the dose is too large, beyond a certain limit, the effect of the drug may have qualitative changes, which may produce varying degrees of toxicity to the body. Therefore, in order to give full play to the effective role of drugs, and at the same time to avoid their adverse reactions, we must strictly control the dose range of drugs. Usually, the dose of drugs can be divided into minimum effective dose, maximum dose, common dose, minimum intoxication dose, intoxication dose and lethal dose. The minimum dose that can produce an effect is called the minimum effective dose; the maximum dose that the body can endure without showing poisoning symptoms refers to the range of clinical effective dose commonly used; the drug has exceeded the maximum, so that the body begins to appear poisoning dose, the so-called drug three-point poison.