Natural Seedling Technology of Purple Mussel

The selection of natural mining Miaohai District In recent years, in the large-scale area of ​​purple mussel rearing area, natural seedling collection has not been a problem. As long as the seedling placement device is put in time, sufficient mussel seedlings can be collected, but for high-density cultivation Districts, in recent years, there has been no lean oyster mussels for many years, the inner row of mussels is not fat for many years, the density of the outer row of seedlings is larger, the density of the inner row of seedlings is too small, and even the seedlings are not harvested. Therefore, in order to choose the sea area according to local conditions, the following conditions should be met in choosing the sea area:
(1) There should be a large amount of pro-shellfish in or near the Miaohai area.
(2) The number of allergic larvae should be the main picking site. This is because the larvae of Scutellaria molitorii have to float for about 20 days before they are attached. During these 20 days, the larvae must be affected by the conditions of the sea, such as the wind and the stream, so that the larvae of the eyeballs that are about to attach will be concentrated where the mining workers there are. Xuan’s capacity is large, and vice versa. This shows that. The growth of pro-Bei is not equivalent to a large number of mining sites.
(3) Choose a sea area where water movement is relatively stable. This is because the range of water flow is not large and the range of larvae activity is small, so that the relative stability and success of picking seedlings can be maintained.
(4) Avoid large water inlets for rivers, industries, and domestic sewage. This will ensure the water quality in the nursery area. The physical and chemical factors are relatively stable, avoiding the infringement of fresh water and sewage, and promoting the success of seedling collection.
Preparation of picking equipment The purple mussel is a oyster shellfish, so it has a lot of picking materials, but from the production point of view, we should choose a wide range of materials, low cost, easy to transport and operate the material to do picking Device.
At present, in the north, 4-strand ropes with a diameter of 1-1.5 cm are used to make four strands of twisted strands. Each length is determined by the depth of the sea area, which is usually 1.5-2 meters and weighs about 0.85-1 kg. Collecting seedlings in the north, transporting them to the south, or breeding in areas with large winds and waves, tends to be somewhat higher. They also use plastic bags or plastic strips to directly collect seedlings, but the effect of picking seedlings is not as good as that of grass ropes, and the amount of transportation is large. Therefore, large numbers of seedlings are not used.
The timing of placing the seedlings on the seedlings depends on the water temperature of the local sea area, the time of pro-shellfish spawning, and the formation time of the metamorphosed larvae (eye larvae), that is, not to miss the breeding boom of the mussels, especially the A reproductive period. Normally, the seedlinger will be used 5-10 days before the eye spot larvae are about to attach. It is also possible to use unfair means to observe the procreative spawning time to determine the color of delivery. In case of sea water showing pink, it is proved that the mussels have spawned; First, observe the color of seawater, and present seawater in pink, which proves that mussels have been produced. Eggs; Second, observe the appearance of water mussels, there is mucus-like outflow, is the sperm-egg, and its third, the interval of anatomy of pro-Shell comparative gland hypertrophy, the pro-Beli who passed the egg remember to appear thin, and not ovulate pro Shellfish gland differentiation is very obvious. In this way, parents will be able to control the timing of ovulation, and after half or ten days, they will be able to vote for the lord and pick the worms.
The method for placing the seedlings is very simple in the floating aquaculture area, as long as the seedlings are used with a diameter of 0.4-0.5 cm and an effective length of 30-40 cm (remove the slings and the body and pick the ends of the seedlings. Polyethylene slings of length) can be hung on the clams, each of which can be hung by 300. In order to prevent the seedlings from floating on the water surface, a part of the body's buoyancy should be reduced, and then the body should be weighed down with a falling stone. The body will be floated, of course, you can also soak the seedlings in advance and hang them in the cocoon, but you should pay attention to not soaking in the stagnant water bay for too long, so as to prevent the water quality from deodorizing and affecting the quality of the harvester.
In addition, a variety of seedling methods such as stakes, iron racks, and rope racks can also be used. In short, as long as the seedlings can be placed in the picking area stably, a large amount of mussels can be harvested.
After 10 to 15 days of seedlings injection, the condition of Miaomiao can be checked. Inspection method: Newly-arrived juveniles with a shell height of 0.02-0.06 cm are difficult to count with the naked eye. At this time, they should be checked by “washing microscopic examination method”, that is, cutting the seedling harvester at different positions. Small section (to keep in mind the proportion of the total length of this small stage picker), wash the larvae as much as possible, remove debris, floating sludge, kill with 5% concentration of formaldehyde, at 10-40 times Under the dissecting microscope or the projector to count one by one, find the amount of seedlings attached to this small section of the harvester during this period, calculate the amount of seedlings attached to each seedling harvester, and then calculate the total amount of seedlings collected. Until the juvenile grows to 0.1-0.2 centimeters, it can use the method to directly use the naked eye to count. Such multiple inspections can predict the situation of the entire seedling collection and be aware of the fact that it is convenient to adjust and remedy the unfavorable factors of seedling collection in a timely manner to achieve the success of seedling production. At present, the level of seedlings collected is generally about 50,000 seedlings per picking seedlings, and 15 million seedlings per seedling. Each of the cultivated earthworms is stocked with 900,000 grains. Each seedling picking can be divided into 16 sets and the loss can be divided into at least 10 sets.