CATDOLL : CATDOLL: How to prevent diseases when breeding Hetanghua yellow bone fish?

1. Yellow catfish is widely distributed in natural water bodies in most parts of my country. It is an economic fish with strong adaptability and can live in adverse environments. It mainly feeds on aquatic insects and shrimps and other invertebrates. Its meat is delicious and is loved by consumers. With the growing demand for yellow catfish, artificial breeding of yellow catfish has become the main choice. However, diseases in the breeding process of yellow catfish will seriously affect the development and economic benefits of yellow catfish breeding industry. The following mainly analyzes and summarizes the common diseases of yellow catfish and the corresponding prevention and control measures.

2. Common diseases and prevention measures of yellow catfish

2.1 Preventive measures for common diseases of yellow catfish

Seasonal change periods such as autumn and Qingming are the high-incidence periods for yellow catfish diseases. It is necessary to do a good job in disease prevention and control of yellow catfish to reduce the losses of yellow catfish farming. First of all, it is necessary to do a good job in disease prevention, clean up the tools used by sick fish in time, disinfect fishing nets, buckets, etc., avoid bringing pathogens into the fish pond to cause cross infection, and use bleaching powder solution for disinfection. Then, it is necessary to do a good job in disinfecting the fish pond. Before the fry enters the breeding pond, the entire pond is disinfected, and copper sulfate is used to kill harmful microorganisms and pathogenic bacteria in the pond. After the fry enters the fish pond, it is disinfected with povidone iodine. In addition, the breeding process of yellow catfish requires the use of high-quality feed to improve the disease resistance of yellow catfish itself and timely manage the water environment of yellow catfish farming to avoid water pollution and reduce the content of bacteria and pathogens in the water environment.

2.2 Bacterial disease prevention and control

2.2.1 Enteritis

Yellow catfish enteritis is caused by infection with Aeromonas punctata. The anus of sick fish with enteritis is red and swollen, and the abdomen becomes enlarged. If you gently press the abdomen of the sick fish, yellow mucus will flow out of the anus of the sick fish. The intestines of the sick fish are inflamed and congested. The sick fish have a poor appetite and move slower than healthy fish. They like to leave the school and move alone.

The prevention and treatment of enteritis first requires systematic and comprehensive disinfection of the breeding pond, feeding high-quality feed with high nutritional value, and disinfecting the live bait with a 3% sodium chloride solution. A certain amount of salt can be added to the feed to feed the fish to relieve the dehydration symptoms of the sick fish. Drug treatment is carried out by spraying 5 g/m3 of dibromohydroxymethyl cyanide into the pond.

2.2.2 “Little red” disease

The "Little Red" disease is mainly caused by the pond environment. After the yellow catfish is infected with Edwardsiella, it will show symptoms of bleeding and congestion on the top of the head. In severe cases, the top of the head will crack and perforate. "Little Red" is prone to occur in an environment with high nitrite and ammonia nitrogen content and poor water quality. The control of the "Little Red" disease can be achieved by improving the breeding environment.

The prevention and treatment of the "red spot" disease of yellow catfish must first start with the water quality regulation of the breeding pond, conduct a systematic and scientific analysis of the pond water quality environment, identify the main salt substances in the pond, and reasonably add certain chemical substances to improve the breeding environment. The staff used potassium permanganate solution, benzalkonium bromide solution and glutaraldehyde solution to spray the whole feed on the previous day, sprayed Zengxingning, Dijingning and Jianganning on the second day, and sprayed EM Yuanlu, high-efficiency composite bacillus and Yishuining on the third day, and mixed florfenicol powder or enrofloxacin powder into the feed for feeding. One week is a course of treatment.

2.2.3 Bacterial gill rot

Bacterial gill rot of yellow catfish is usually caused by pathogens such as Edwardsiella and Aeromonas hydrophila. Yellow catfish suffering from this disease have pale gills, mucus, rotten gill filaments, black head, and severe gill cover bone ash corrosion and falling off.

The prevention and control methods for bacterial gill rot are as follows: use povidone iodine diluted 400 times with water to spray the entire pond, use it once every two days, and use it continuously for about three times; mix enrofloxacin powder with feed, and reasonably choose the amount of feed and the amount of medicine to be mixed according to the number of yellow catfish; use bromine chloride powder diluted one thousand times with water to spray the entire pond, and use it continuously for two days.

2.3 Trichodiniasis

Trichodiniasis in yellow catfish is a common parasitic disease caused by the parasitism of trichodinia.

Yellow catfish parasitized by wheelworms will appear restless. Severely parasitic fish will swim frantically along the edge of the pond. Under a microscope, large numbers of wheelworms can be seen in the skin mucus and gill filaments of the diseased fish.

Wheelworm disease can be controlled by spraying a mixture of ferrous sulfate and copper sulfate throughout the pond, and using recycled water wheel net diluted three thousand times with water for spraying throughout the pond.

2.4 Myxosporidiosis

Myxosporidiosis is caused by infection with myxosporidia. The diseased yellow catfish will have a certain number and shape of small white spots on its body surface, and its skin will ulcerate. In severe cases, the diseased fish will slowly die.

Myxosporidiosis can be controlled by spraying 90% crystal dichlorvos throughout the pond, once every two days, with a course of treatment consisting of three times. It can also be controlled by spraying cypermethrin throughout the pond, and the dosage of the drug can be reasonably determined based on the water depth of the pond.

2.5 Nutritional diseases

Nutritional diseases are mainly caused by an imbalance in the nutritional structure of feed. Too much or too little nutrition in the feed will cause the growth and development of yellow catfish to be disordered, affecting the yield of yellow catfish. Nutritional diseases of yellow catfish are manifested as vitamin deficiency and fatty liver disease. The diseased ones have discolored livers, black bile, and enlarged gallbladders.

The prevention and control of nutritional diseases is mainly achieved by changing the original feed ratio. The feed formula is scientifically and reasonably determined based on the growth habits and breeding characteristics of yellow catfish to ensure that the feed quality meets the growth and development requirements of yellow catfish.

3. In summary, in the process of breeding yellow catfish, various diseases of yellow catfish will seriously reduce the yield of yellow catfish and affect the economic income of farmers. Therefore, it is necessary to take preventive measures for common diseases of yellow catfish, implement the breeding policy of prevention first and combination of prevention and elimination in daily life, clean and disinfect fish ponds regularly, feed high-quality feed, and ensure the strength and health of fish species.

01 Ascites (bacterial disease)

Cause of disease: Also known as hemorrhagic ascites, it is caused by Edwardsiella tarda and others.

Symptoms: The fish eat less or no food, swim alone or float on the water surface, have a swollen abdomen and ascites, and dissection shows that the stomach or intestines are swollen with gas, and the liver is congested or bleeding; there is occasional bleeding on the body surface, fins or fin bases, head and belly. In the later stage, the back and head skin will ulcerate.

Prevention and control measures:

Disinfection: Use [chlorine dioxide effervescent tablets]/[iodine] externally to disinfect water bodies;

Oral administration: Take [Fuyukang]/[Enwei] + [Changxin'an] + [Yinchenlidankang]/[Ganbao] + [Huangqi Multivitamin] at the same time for 5 to 7 days.

02Enteritis

Cause of disease: caused by infection with Aeromonas punctata.

Symptoms: The abdomen of the diseased fish is swollen, the anus is red and swollen, and yellow mucus flows out of the anus when the abdomen is lightly pressed; when the fish abdomen is opened, the intestines are inflamed and light red, and blood and pus fill the intestines; the diseased fish swim alone, move slowly, and have a decreased appetite. It is prevalent from June to September and is most harmful to adult fish and broodstock. During this period, the light intensity is high, the air and water temperatures are high, there is a lot of feeding, the water quality is easy to deteriorate, and bacteria breed. The yellow catfish has a high feeding intensity and a vigorous metabolism, making it particularly susceptible to enteritis. Preventive measures:

1. The pond must be thoroughly cleaned and disinfected, and the bottom and water must be adjusted.

2. Do not feed moldy or rotten feed. Live bait should be disinfected with 2-3% salt solution, and 1% salt or 0.1% fresh garlic juice should be added to the feed regularly for feeding.

Treatment measures:

1. Take [Changxin'an]/[Florfenicol] + [Ganbao]/[Fuzheng Jiedukang] orally;

2. After the disease is under control, use [Bottom Reform Pioneer] to reform the bottom, and use [Iodine-Free]/[Iodine-Free] for disinfection, and then apply [Water Purification] after 2 to 3 days.

03 Split head disease, also known as red spot (bacterial disease)

Cause of disease: Caused by Edwardsiella siluri, Aeromonas veronii, etc.

Symptoms: The top of the head is swollen and swollen, forming a pustule, the skin of the head is ulcerated, and in severe cases, the top of the head is perforated or cracked. In even worse cases, the skull is hollowed out, forming a narrow cavity, and the brain tissue flows out; there are blood spots or blood spots on the body surface. Dissection shows that the abdominal cavity has light yellow liquid, the liver, spleen, and kidneys are all swollen and deformed, and the stomach is empty or filled with liquid. When the diseased fish swims, it swims sideways or turns around, with the head down and the tail up.

Prevention and control measures:

1. Prevention: Spray [Iodine] for disinfection during the epidemic season, and take [Duxikang] internally for prevention;

2. Treatment:

Disinfection: Spray [water poison] all over the pool on the first day, and [iodine] all over the pool on the second day;

For oral administration: [Fuyukang]/[Enwei]+[Duxikang]+[Yinchenlidankang]+[Huangqi Multivitamin] for 5 to 7 days.

3. After the condition stabilizes, sprinkle [Bottom Improvement Pioneer] or [Bottom Improvement Kang] throughout the pond to improve the bottom to prevent recurrence of the condition.

Note: This disease often occurs concurrently with parasitic diseases such as wheelworm and ringworm. When concurrent diseases occur, the insects should be killed first, and then the above methods should be used for prevention and control.

04Ulcers (bacterial diseases)

Cause of disease: caused by Aeromonas sobria, Aeromonas hydrophila, Vibrio cholerae, etc.

Symptoms: Ulcerative red spots or erythema in the form of dots or blocks appear on the body and abdomen of the yellow catfish. There are often large areas of discolored spots in the middle and back parts of the body. The gill filaments are anemic and a swollen liver can be seen during dissection.

Prevention and control measures:

1. Disinfection: Spray the whole pool with [water poison] on the first day, and spray [iodine] on the second day;

2. For oral use: take [Fuyukang] + [Duoxikan] + [Yinchenlidankang] + [Huangqiduowei] orally at the same time for 7 to 10 days.

3. After the condition stabilizes, sprinkle [Bottom Improvement Pioneer] or [Bottom Improvement Kang] throughout the pond to improve the bottom to prevent recurrence of the condition.