First, after the mouth worm.
Bactrocera dorsalis, also known as shield ciliate, belongs to Bactrocera dorsalis, which is parasitic on the breathing tree of sea cucumber. The suitable survival temperature of this insect is 4- 12℃, the salinity is 25‰-35‰, and the PH value is 7-9. When the population density reaches a certain level, it will cause tissue damage and ulceration, which will harden the sea cucumber and cause serious excretion. (The picture below is taken from the hard sea cucumber breathing tree on the reef)
When spring, summer, autumn and winter alternate, it is suitable for the season and water temperature of the insect's mass reproduction.
Second, the situation
1, sediment difference
(1) The bottom of the old circle has been aging for many years, and organic matter has accumulated, which is easy to breed mouth worms.
(2) In a pond with a lot of grass, grass will spread at the bottom of the pond after death, which will lead to the deterioration of the bottom environment.
(3) Overfeeding caused too much organic matter in the pond, which provided nutrition for the latter and led to the latter's massive reproduction.
(4) In pursuit of cheap use of insoluble organic fertilizers such as chicken manure, many farmers lead to the proliferation of harmful microorganisms such as miscellaneous bacteria in ponds and the deterioration of sediment, which creates conditions for the occurrence of oral worms.
2. Poor physique
(1) In spring, the temperature difference between day and night is large, and the unstable climate causes the sea cucumber to be under great pressure and weak.
(2) In a pond with a lot of rotten grass, sea cucumbers ate rotten grass and other corrupt substances, and they developed Darkmouth, swollen mouth and enteritis, which made them in poor health.
(3) Kill grass, fish and clean water. Lead to sea cucumber poisoning and weakness.
(4) In spring, the health status of some seedlings damaged by machinery is poor.
(5) Ponds with large water changes are easy to cause stress and weaken the constitution of sea cucumbers.
Third, why are you infected with oral worms?
Poor sedimentation (root cause) is easy to breed faucets. Respiratory tree is the respiratory and excretory organ of sea cucumber. A lot of seawater passes through the breathing tree. Stress, drug stimulation and mechanical injury (inducing factors) lead to poor constitution of sea cucumber (direct cause), which easily leads to a large number of parasitic faucets in the capsule of breathing tree, and a small amount of parasitism leads to reduced food intake, weakened vitality and even hardening of sea cucumber. A large number of parasitism will lead to the phenomenon of sea cucumber returning to the reef and vomiting.
Therefore, on the whole, the key to prevention and control lies in improving the environment, reducing drug stimulation and enhancing the physique of sea cucumber.
Fourth, how to comprehensively prevent and control it.
1, improve the constitution of sea cucumber and reduce the pressure.
It is suggested to change water several times in spring, which can supplement some nutrients and natural bait, increase water flow, promote physical exchange between water and bottom, and at the same time, it is beneficial to the reproduction of bacteria and algae, indirectly providing bait for sea cucumbers, and has little effect on sea cucumbers that eat normally. Keeping the average water level around 1.3m can not only reduce the stress of climate change on sea cucumbers, but also facilitate the observation and foraging of sea cucumbers on the beach. After weeding, killing fish and purifying water, change the water several times in time and detoxify and reform the bottom as soon as possible to reduce the hardness and physical decline of sea cucumber caused by stimulation or poisoning. When the state of sea cucumber is not good, it is suggested to use "activation" to sprinkle nutrients "nutrition express line" to improve the state of sea cucumber and ensure that sea cucumber has a good physique.
2. improve the bottom material and hinder the reproduction of oral worms.
After the spring, due to the long winter, feces, dead algae, dead grass and other toxic and harmful substances piled up. It is suggested to use "Dijuan" with surfactant as the main component and "bottom aeration" with detoxification as the main component to degrade toxic and harmful substances at the bottom of the pond. In large ponds with black and smelly bottoms (e.g. after weeding and large-scale feeding). ), it is suggested that strong oxidation "recharge" combined with detoxification "bottom oxygenation" should be used in time to quickly remove excess organic matter at the bottom, inhibit the reproduction of harmful bacteria and microorganisms, create a good bottom environment and reduce the occurrence of oral worms.
3. Feed correctly and take part in physical exercise.
In the season when oral worms multiply in large numbers, it is suggested to feed them properly and give priority to the ecological material "Limiaoduo", which has good digestion and absorption, no residue and no odor. On the one hand, sea cucumber can obtain good nutrition supply and strengthen the body, on the other hand, it can cut off the nutrition source of oral worms and reduce the incidence of oral worms.