Fish hepatobiliary syndrome is one of the most frequent diseases in aquaculture today, with a wide range, great harm and high mortality rate; it mainly harms grass carp, crucian carp, carp, bluefish, bream, tilapia, yellow jawfish, eel and other farmed fish that feed on compound feed; and the affected fish will experience a decrease in their own resistance, which will cause other diseases and seriously endanger healthy aquaculture. With the increasing density of aquaculture, the pursuit of profits increases, in order to shorten the breeding cycle, so a large number of high-protein feed, greatly increasing the burden of hepatobiliary intestine; in addition, some feed manufacturers of compound feed elements do not match the nutritional needs of the fish growth stage, indigestion, the same increase in liver and gallbladder burden.
The degree of health of the liver and gallbladder directly determines the digestion, absorption and immunity of the fish body, there is a saying that "the body is the capital of the revolution", raising the liver and gallbladder well, in order to raise fish, has become the consensus of the majority of farmers, then, this article, will lead us to a thorough understanding of hepatobiliary syndrome.
Manifestations of hepatobiliary syndrome, fish body color black, swimming alone, check the internal organs, mainly liver color lesions, normal fish liver should be pink, like pig liver, and elastic, not easy to break, the liver where the lesion occurs, will appear yellow, white, green or full of white nodules, and slight touch is easy to break. The gallbladder lesions are followed by enlargement, darkening in color, and dark green.
First, what are the causes of hepatobiliary syndrome
1. The amount of feed feeding is unreasonable
Some farmers are eager to raise fish to market specifications, shorten the breeding cycle, they feed a large amount of feed, fish growth rate is accelerated, but at the same time, due to the intake of nutrients exceed the needs of their own physiological activities, and finally through the liver into fat in the liver and mesentery continue to accumulate, increasing the burden of liver and gallbladder.
Recommendation: the daily feeding amount of the water temperature at 15 ° C - 20 ° C is 1% - 1.5% of the total weight of the eating fish, the water temperature is 2% - 4% of the total weight of the eating fish at 20 ° C - 28 ° C, the water temperature is lower than 15 ° C and above 30 ° C, try to reduce the amount of feeding; you can also observe the phenomenon of fish eating, when feeding to 70% of the fish has left the feeding table, you can stop the feed at this time. Secondly, it is to do a small number of meals, the smaller the size of the fish, the more should be fed. It is recommended that fry be fed 4-6 meals and adults 3-4 meals.
2, feed itself factors
Now it is generally (compound feed with green feed (grass) feeding, some manufacturers produce feed nutrients with unreasonable collocation, will lead to fish indigestion, the addition of some growth hormone will directly increase the liver load, in addition, feed mold, expiration, rot produced by mycotoxins, corn erythrodenone, etc. have direct damage to the liver and pancreas of fish.
Recommendation: choose well-known manufacturers, large brands of feed, often check whether the feed of the bait machine remains dry, whether it is fed in time, can not be placed in excess of the bait machine, can not eat the easy to deteriorate, in addition to pay attention to whether the feed has mold, pay attention to the feed shelf life. At the same time of feeding, you can add liver protection package Meikang No. 1 + Meikang No. 2 + Meikang No. 6 in the feed, with a strong liver protection and bladder protection, repair the function of necrotic liver cells, you can also directly add liver protection plus immune feed - liver and intestine health, no need to mix medicine, direct feeding, easy to use, verified by the majority of farmers, the effect is very good.
3. Toxic substances in the environment
Heavy metal pollution: mainly from industrial and domestic sewage, and the long-term use of copper sulfate, zinc sulfate, inferior fertilizer aquatic products or some prohibited drugs will also increase the content of water weight metal, heavy metal excess will seriously damage the fish nervous system, hematopoietic system, respiratory system and excretion system, which will lead to metabolic abnormalities, liver necrosis, hepatomegaly, sepsis, gills; heavy metals are most likely to attach to the liver, there is direct damage to liver cells, affecting the normal function of the liver, resulting in fat can not function normally out of the liver, Thus causing serious effects on the liver 'fatty liver'. Because the liver has a detoxification function, the body's toxins will eventually be decomposed and discharged through the liver, if the water quality deteriorates for a long time, such as ammonia nitrogen salt exceeds the standard, the algal toxin produced by algae death will also increase the burden on the liver;
Recommendation: Frequently fill fresh and pollution-free water sources, while doing a good job in water quality management, Dikang No. 1 + water treasure is used regularly, change the bottom to detoxify, reduce the accumulation and production of toxic and harmful substances in the water.
In addition, the selection of high-quality non-irritating fertilizer aquatic products, rich in silicates, trace elements, high phosphorus, and fully soluble in water amino acid fish fertilizer - fat Shuang No. 1, control the water ammonia nitrogen salts.
4. Unreasonable use of insecticidal disinfection drugs
The traditional breeding mode adopts regular insecticidal, disinfection, algae killing drugs to treat water quality and control fish diseases, short-term use may not have obvious symptoms of poisoning, but long-term use will have drug residues, disrupting the ecological balance of water bodies and damaging the liver and gallbladder of fish.
Suggestion: scientific breeding mode, it is recommended to change the bottom, water transfer, regularly change the bottom of the pool, parasites are difficult to grow up, a year of insecticidal drug use control in 2-3 times is enough, do a good job of qingming and white dew insecticidal work, the rest of the time according to the specific situation, there are insects to kill, no insects must not blindly kill insects. In addition, when killing insects, try to choose safe and efficient insecticides that stimulate small insecticides, and do not use heavy metals, pesticides and other residual heavy and stimulating drugs.
5. The breeding density is too large, and the water quality deteriorates
Blindly increase aquaculture, the amount of feeding is too large, beyond the scope of water regulation, will cause the concentration of ammonia nitrogen in the water body is too high, which causes the ammonia metabolites in the fish to be difficult to discharge normally, thereby accumulating in the blood, causing fish metabolic imbalance to cause liver and gallbladder disease.
Recommendation: reasonable control of stocking density, to prevent the accumulation of residual bait feces too much, resulting in serious water pollution, followed by the use of excess ammonia in the pond, regular supplementation of beneficial bacteria such as mushroom No. 1 or em mother bacteria, with the use of high phosphorus fish fertilizer - fat Shuang No. 1, convert excess nitrogen elements, turn waste into treasure, make full use of the nutrients of residual bait feces.
6, the cause of the fish body itself
There are problems with the liver and gallbladder of the fish fry they buy, because the process of water scale coarse needs to be fed high-protein animal protein feed, and some farmers in order to reduce the breeding cycle, a large number of feeding leads to overloaded operation of liver and gallbladder.
Recommendation: When buying fry, take a sample to check the physique of the fry, the health of the internal organs, and eliminate the purchase of problem seedlings from the source.
Second, how to treat
If there is hepatobiliary lesions, the following means can be used for conditioning treatment, first of all, reduce the amount of feeding by 10%-50%, control feed feeding, more meals; at the same time take "fish blood Ning + Meikang No. 2 + Meikang No. 6" a group of mixtures can feed 2000 pounds of fish, continuous feeding for 5-7 days, after the death situation improves, and then take Meikang No. 1 + Meikang No. 2 + Meikang No. 6, a group of mixed 1 bag of feed or liver and intestine health (20kg per bag) 1 bag mixed with 10 bags of ordinary feed, feeding 5 days stop 5 days, even feeding 2-3 courses can be.
Because hepatobiliary syndrome is a chronic disease, not two days a day, so the treatment needs a certain amount of time, according to the course of treatment, do not stop treatment after getting better, the later stage is very easy to rebound. The most fundamental treatment method is still to rely on scientific breeding technology for prevention, usually pay attention to feed management and do a good job in the protection of liver and gallbladder, and when the disease is on the body, it is already more than worth the loss.