The information on preventing and treating some common diseases in freshwater fish with herbs.
Currently, the overuse of antibiotics in the treatment of aquatic diseases is becoming more and more complicated, this leads to an increasing trend of using herbs to treat aquatic diseases, solve the current situation of drug resistance, food safety and human health that aquaculture systems are facing to.
Using herbs to treat and prevent diseases in aquatic animals is very effective, saves cost, materials are available in nature, unpolluted, and are safe for animals and human health.
Here are some common diseases found in freshwater fish and preventive solutions using herbs.
Septicaemia caused by Aeromonas Hydrophila
Aeromonas Hydrophila bacteria are widely distributed in the aquatic environment, cause of diseases in freshwater fish and wild fish. This bacterium is always present in water that has lots of organic substances and in ponds with excess food. Bacteria are well adapted to environmental conditions with temperatures from 25 – 35oC. The disease usually appears in the hot seasons of the year, with the highest concentration in the late spring and early summer months. The smaller the fish, the higher the mortality and infection rate, up to 80% of the fish in the pond or nursery tank.
Infected fish usually have dark skin and die very quickly after 2-3 days, appear hemorrhage around the anus, tail and fins are necrotic, scales fall off. The mortality rate of the fish is higher when the fish is in shock and severe lack of nutrition.
To prevent diseases caused by the bacteria Aeromonas Hydrophila effectively, farmers need to choose good breeds, buy them from reputable and quality hatcheries to avoid inbreeding, fish must be healthy, have the same size, no defects, bright colors and no disease.
Herbal solutions: Using wedelia chinensis to prevent and treat bacterial deseases caused by Aeromonas Hydrophila.
Wedelia chinensis is a kind of weed found around the house or in the backyard, grows horizontally on the ground, long-lived. The body is green, has small hard white hairs, the leaves are almost sessile and symmetrical with each other, growing in an elongated oval shape, with two pointed ends, the flower cluster has head-shaped, the flower stalk is long beyond the leaf branches. Flower is bright yellow. Wedelia chinensis is effective against all 6 bacteria: Vibrio parahaemolyticus, V. harveyi, V. alginolyticus, Aeromonas hydrophila, Edwardsiella tarda and Hafnia alvei cause disease in both fresh and brackish water fish.
- Fresh use: Crush 3.5 – 5 kg of fresh wedelia chinensis and mix with food for 100 kg of fish/ day for 7 consecutive days.
- Dried use: Pulverize dried plants to mix with fish feed at a dose of 0.1 – 0.2 g / kg feed.
The bacteria Aeromonas punctata is widely distributed in the water environment and in the bottom layer where has a lot of organic humus or polluted pond environment. Bacteria grow well at temperatures from 25oC. The disease usually appears in the season with high temperatures.
Diseased fish often refuse to eat, move slowly, break up groups and die quickly. The fish abdomen contains fluid or not, enlarged, hemorrhagic around the anus, red convex, erythema, inflamed intestine, red intestinal wall, yellow fluid in the anus.
– Improve pond well before stocking, absorb mud from pond bottom before stocking.
– Fish feed must be qualified, no musty, rancid.
– Disinfectingbefore stocking with salt water 2-3% for 10-15 minutes to eliminate pathogens. Periodically use 10g garlic mixed with 10kg feed for 3 days.
Farmers use eclipta prostrata to prevent and treat hemorrhage and enteritis in fish. This plant often grows around the fields and cemeteries, it has white flowers and pointed leaves.
- It can be used fresh or dried, eclipta prostrata can be pulverized and mixed with food, the fresh one can be crushed to get the liquid and mix with feed. Feed the fish continuously for 7 – 10 days.
- Also, we can add garlic into10g of eclipta prostrata then mix with 10kg of feed, use continuously for 3 days to prevent intestinal diseases and helps effective digestion.
Diseases caused by parasites
Common parasitic diseases in fish such as anchor parasitic diseases, wheel worms, parasitic helminths, 16-hook trematodes or 18-hook trematodes … all cause fish death at a high rate, especially in the fingerling stage
Chinaberry leaves kill parasites in fish efficiently.
- Fresh use: Use 150 – 200 kg of chinaberry leaves or branches per 1000m2, tie them up in bundles, then put them in the four corners of the pond or at the top of the water source of the pond where the fish are parasitic until the leaves decomposed, then take them out of the pond.
- Dried use: dry leaves and branched and pulverize, use 0.3 – 0.5kg / m2 3 days before stocking.
- Can be used periodically for ponds with a dose of 100kg of leaves or branches / 1000m2.
For the parasite is the fish lice
The disease is caused by species of the Argulus genus, the fish lice parasitize all over the body, often cling to gills, mouth, body, fins, using the sensory to absorb and suck the fish blood, making the fish feel itchy, move abnormally at the same time destroying the skin, causing ulcers to facilitate bacteria, fungi, and other parasites to invade and cause disease in farmed fish. At the same time, the fish grows slowly or die many.
Use fresh lemon and salt to make a mixture to splash into the fish cage.
- Stir blended fresh lemons with sea salt at a rate of 2/3. Dilute this liquid with water at the rate just enough for the fish cage then splash evenly all over the cage.
- Note: For the river cage, it is necessary to use tarpaulins to flow over the top of the cage, pour the mixture down for 10 minutes, then remove the tarpaulin so that water can circulate into the cages.
- When using this method for fish cultured in ponds, it is necessary to pay attention to the dosage, because the overuse makes fish lose oil and die.