Ten Suggestions for Improving the Efficacy of Fishery Drugs

Fish inevitably suffer from various diseases during the aquaculture process, and when treated with drugs, the results are often unsatisfactory because the therapeutic effect of drugs is affected by various factors. Here, based on my own experience, the author puts forward "ten points" of suggestions for improving the efficacy of fishery drugs, for the reference of the majority of farmers when using drugs.

1. Accurately diagnose fish diseases and use drugs according to the symptoms. Using drugs according to the symptoms is one of the most basic conditions for improving the therapeutic effect of drugs, especially for some fish diseases that are easily confused (such as: gill rot caused by Sinergasilus parasitism and gill rot caused by bacterial infection, etc.). The cause of the disease must be carefully identified, and only by using drugs according to the symptoms can the effect of curing the disease be achieved.

2. Accurately measure the water body and calculate the accurate dosage. The dosage of oral drugs should be calculated according to the total weight of the fish feeding in the pond or according to the daily feed ration.

3. Clarify the sensitivity of different fish species to different drugs. In order to avoid the formation of drug damage, before using drugs, we must first clarify that different fish species have different sensitivities to drugs. For example, snakehead is relatively sensitive to ferrous sulfate, and scaleless fish are relatively sensitive to trichlorfon. If these drugs are used, not only will the fish disease not be cured, but the cultured subjects will be poisoned and die.

4. Pay attention to the antagonistic and synergistic effects between drugs. When two or more drugs are mixed and used, two completely different results may appear, namely: antagonism, which makes the drug effects offset each other and reduces the effect; synergism, which makes the drugs react with each other and enhances the drug effect. Therefore, if two or more drugs really need to be mixed and used, it is best to use them under the guidance of technical personnel.

5. When splashing drugs over the whole pond, it is best to feed first and then splash the drugs, because after the drugs are splashed, the appetite of the fish will decrease. In addition, it is best to use drugs at 9:00-10:00 in the morning or 4:00-5:00 in the afternoon on sunny days, and avoid using drugs when the sunlight is direct at noon, because the higher the temperature, the faster the drugs volatilize, and the shorter the duration of the drug effect; also, it is not suitable to use drugs on cloudy and rainy days (except for some drugs that can release oxygen), because the light is too poor on cloudy and rainy days, and it is easy to cause oxygen deficiency in the fish pond after using drugs.

6. When splashing drugs over the whole pond, it must be uniform. For some drugs that are difficult to dissolve and have residue (such as: bleaching powder), the residue must be filtered out, so as to avoid the residue entering the pond and being mistakenly eaten by fish, causing poisoning and forming drug damage.

7. When splashing drugs over the whole pond, one should start from the upwind area and gradually splash toward the downwind area, and people should stand in the upwind area. This can use the effect of wind to make the medicinal liquid quickly distribute evenly in the pond water, while also ensuring the safety of the person applying the drug.

8. Irregularly change the varieties of drugs. When the same drug is used for a long time to treat fish diseases, the effect will be very good at first, but after a long time the drug effect often weakens, because the pathogen has developed resistance to the drug, that is, drug resistance. Therefore, the varieties of drugs should be changed irregularly for alternating use.

9. When feeding oral medicated bait, it is best to first feed part of the normal feed, let the healthy fish eat their fill first, and then feed the medicated bait, so as to ensure that those sick fish that are already ill but still have some appetite can eat the medicated bait and achieve the therapeutic effect of the drug.

10. The containers used to dissolve or prepare drugs should be plastic buckets or wooden buckets, and metal containers cannot be used, because most fishery drugs easily undergo chemical reactions with metals, thereby changing the composition and properties of the drugs.