preface
The cruzi crayfish, also known as the Brazilian lobster or red lobster, is a valuable freshwater lobster native to Australia and Papua New Guinea that is prized for its delicious meat, nutrient richness and high economic value.
Adult individuals are usually up to 20-30 cm in length, but there have been reports of maximum individual lengths of up to 60 cm, covered with a hard shell, a rich red or orange color, with black spots and blue edges, and four distinct dorsal ridges (the "four-ridged lobster").
This shrimp omnivore, mainly feeding on aquatic plants, algae, zooplankton, etc., has strong adaptability, can survive and reproduce in various water environments, grows fast, has strong fecundity, strong adaptability, is an ideal breeding species, attracting the attention of many farmers.
Its breeding technology includes shrimp fry cultivation, water quality management, feed management, disease prevention and control, etc., scientific and reasonable management measures, can improve breeding efficiency, reduce loss rate, and ensure the healthy growth of Protochovitae cruzi.
Seed breeding technology
1. Breeding pond environment
Protochovius cruzi is a territorial and cannibalistic creature that chooses to live in burrowing in both winter and summer. In order to meet the burrowing needs of Protochovius cruzi, it is best to use earthen ponds in breeding ponds, while shallow water areas should be set up and necessary mounds should be built.
If you want to improve the breeding rate of seeds, you also need to create a good ecological environment. One of the important steps is to transplant a certain amount of aquatic plants in the pool. The area of aquatic plants should account for 1/3 to 1/2 of the breeding pond, and it is necessary to consider the selection of appropriate aquatic plant varieties when transplanting.
You can choose floating plants, submerged plants and emergent plants, all three need to be taken into account. Weeds should remain on the slope of the pond, which can play a role in consolidating the soil and protecting the cave, and some trees should be planted on the ridge to further enrich the ecological environment.
For current aquatic plant selection, some major varieties can be considered. Among them, floating plants include water lotus, water hyacinth, locust leaf ping, water celery and yellow flower water dragon, while emergent plants include reed, wild rhombus white, ci mushroom, cattail and lotus root.
The submerged plants include Marais, Ichrysophyllum algae, snapdragon algae, bitter grass and polyalgae, etc., and you can also lay straw, reeds and other plant straw under the water, which is conducive to the molting and hiding of juvenile shrimp.
2. Broodstock of the original crayfish of Kirier's is selected
The sexual maturity age of Protochovy cruzi is generally more than 9 months old, the individual size is more than 30 g/piece, and the selection of broodstock is usually carried out in August and September. The criteria for selecting broodstock are very important. The color of broodstock should be dark red or black-red, shiny, and smooth and free of attachment.
Individual size is also an important factor, both female and male individuals should weigh more than 30 grams, preferably male individuals larger than female individuals. Both females and males of broodstock should have complete appendages and no damage, strong physique, strong mobility, and the male-female ratio should be 1.5:1.
During the culture process, broodstock can usually be farmed pond shrimp. The stocking capacity per mu is generally 40~50 kg. In mid-October, after intensive cultivation, the pond water level can be lowered in stages, forcing the crayfish into the wintering period and carrying out corresponding wintering management.
During wintering, it is crucial to prevent rats from harming broodstock. In addition, it is also necessary to pay attention to the conditions of the wintering environment to ensure that the right temperature and water quality are provided to ensure that the crayfish can safely survive the cold winter.
3. High density of soil pond
After experiments, it was found that Protoctofish cruzi has strong hunger tolerance. After being able to feed the protocrayfish for more than 8 months without feeding, they survived in a glass, despite significant weight loss. This discovery inspired me to use a new way to improve the survival rate of seed breeding.
According to my idea, in late autumn, when the crayfish begin to enter the winter burrows, try lowering the water level in the pond. Then, when spring comes, around mid-March to early April, when the water temperature exceeds 18 degrees Celsius, the water level of the pond can be raised at one time to force the broodstock to leave the burrowing and start breeding seeds.
In this way, the size of the seeds can be relatively consistent and their breeding survival rate can be improved, so that 100,000 to 300,000 young shrimp can be produced in ponds stocked with 40 to 50 kg of broodstock per acre.
For farmed ponds, I also have a little trick to increase the size and yield of shrimp, which can gradually increase the water level of the pond, which can increase the size of the juvenile shrimp in the same pond, which not only helps to implement rotation fishing, but also further improves the size and yield of farmed shrimp.
Breeding environment creation technology
In the culture of Protocrayfish cruzi, it is widely accepted that they are adaptable and can survive in a variety of environments, even in sewage trenches. However, this is not the case.
In harsh environments, the molting rate of Protochop cruzi is either very slow or not occurring at all, and their survival time is short, the survival rate is extremely low, and there is almost no mating and reproduction behavior.
The current study found that the success of crayfish farming is not only related to the water quality of the pond, but also related to the soil quality of the pond, the density of aquatic plants in the water and the terrestrial vegetation on the shore of the pond, which can directly affect the culture survival rate, yield and quality of commercial shrimp of Protochop cruzi.
In order to regulate water quality, some technologies are also used. Preferring shady environments, it usually comes out in the evening and dawn to feed, mainly in shallow waters, and lives underwater. Juvenile shrimp feed mainly on plankton.
Therefore, after entering the water in spring, an appropriate amount of base fertilizer will be applied, generally 150~300 kg of organic fertilizer per mu, which can be splashed in the whole pond, or they can be stacked in the shallow water around the pond to cultivate zooplankton such as rotifers, clades and plaid feet suitable for young shrimp. In the middle and late stages, in order to improve the specifications of commercial shrimp, to keep the water fresh and the transparency should be kept above 40 cm.
The cultivation of a certain proportion of aquatic plants is also very important for the cultivation of Protoclamus cruzi, and the ecological environment of the aquaculture water body is controlled and improved through the growth and reproduction of aquatic plants. Aquatic weeds in shrimp ponds are important environmental factors and a source of nutrients for crayfish, as well as providing essential habitat and shelter. Aquatic plants also have the effect of purifying and stabilizing water quality, which can effectively improve the quality of commercial shrimp and reduce breeding costs. Therefore, in the breeding process, planting aquatic plants is very critical.
However, there are some basic requirements for planting aquatic plants, the aquatic plants in the shrimp pond should be evenly distributed, and different kinds of aquatic plants should be planted together to maintain the corresponding proportions to meet the growth and habitat needs of Protoclamus cruzi. When selecting and transplanting aquatic weeds, attention needs to be paid to adapt to the requirements of Protochoid cruzi culture.
In addition to regulating water quality and planting aquatic weeds, other factors can also affect the culture effect of Protochovitaeus cruzi. For example, the soil quality, temperature and light of the pond need to be reasonably controlled and managed, and the weeds in the pond must be cleaned regularly, and the pool facilities must be inspected and restored, which are also important links to ensure the smooth progress of the culture of Protocrayfish cruzi.
Farming mode of Protochous cruzi
1. Seedling density control technology
The culture survival rate of the original shrimp can usually reach more than 70%, and the density of juvenile shrimp should be controlled at about 15,000 to 20,000 per mu to ensure good breeding results. However, due to the strong reproductive capacity of shrimp populations, shrimp populations in aquaculture water bodies are unevenly distributed, and it is difficult to control the density and accurately count.
Therefore, determining the density of aquaculture water is key, and the common method used is to determine the density of juvenile shrimp based on the feeding amount and size of the shrimp, combined with empirical techniques. In order to increase the yield and quality of culture, regular density determination and rotational harvest strategies are required during the culture process to ensure that the size and quality of the culture are improved, which helps to achieve higher culture success rates and maximize the culture potential of Protomytonium cruzi.
3. Water quality management technology
Poor water quality can also breed a variety of pests, such as parasites, bacteria, etc., leading to outbreaks and spread of diseases. Serious water quality problems can even lead to the death of shrimp in large numbers, making farming plans completely impossible. Therefore, when cultivating Protocini cruzi in dense ponds, it is necessary to master the principles of water quality management and maintain water quality transparency at about 40cm. Adjust in time according to seasonal changes, water temperature and water quality conditions, add water, change water, fertilize, etc. in a timely manner to create a good water quality environment.
In addition, the following principles need to be followed to manage the water quality of Protochop cruzi:
(1) The principle of "shallow spring, full summer"
In spring, keep the water shallow, about 0.61 meters. This helps aquatic weeds grow, snail mantis reproduction, and juvenile shrimp molt growth. In summer, due to the high water temperature, the water depth should be controlled to about 11.5 meters to help the cruzi crayfish survive the hot season.
(2) The principle of "fat first, then thin"
In the early stage, shrimp fry are small, and it is necessary to provide fertilizer water, cultivate plankton, and improve the survival rate of young shrimp. In the middle and late stages, the water quality should be relatively thin, which should promote the rapid growth of crayfish and increase yield. The transparency is about 30cm in the early stage, and it is maintained above 40cm in the later stage.
In addition, every half month, quicklime water can be sprayed, the dosage is about 10kg per mu of water depth of 1 meter, which helps to maintain the pH value of the pond between 7.5~8.5, increase calcium segregation in the water, such treatment can maintain the molting growth of crayfish.
It is also necessary to pay attention to the diet of crayfish, which has a diverse diet and rapid growth, but the quality and price of feed have an important impact on the quality, yield and economic benefits of farming.
On the basis of in-depth understanding of the nutritional requirements, growth characteristics and feeding habits of Protochop cruzi, it is necessary to study different types of food, such as protein, fiber and starch, to meet the growth needs and disease prevention functions of crayfish at different stages of development. At the same time, through experiments, a reasonable feeding technology suitable for C. cruzi can be developed to improve the quality and yield of aquaculture and increase economic benefits.
4. Prevention and control technology of aquaculture diseases
The farm's facilities should be disinfected before a new batch of Protocini cruzi is stocked. Pools, equipment, and pipes can be disinfected at the right concentration and time to kill potential pathogens using the right amount of disinfectant, such as bleaching powder, hydrogen peroxide, etc.
Vaccination is an effective preventive measure against certain pathogens. Depending on the local epidemic situation and recommendations, select the appropriate vaccine and follow the instructions.
At the same time, it is also necessary to provide suitable food to ensure the quality of feed and the balance of nutrients, and avoid overfeeding and waste. Clean sediment and debris regularly to avoid the accumulation of organic matter.
It is also necessary to regularly monitor the disease of the protocrayfish cruzi in the farm to detect the early symptoms of the disease in time. The initial judgment can be made by observing the behavior, appearance and activity of Protochop cruzi, as well as understanding the common symptoms of the disease.
Once the presence of an epidemic is detected, rapid response and isolation measures should be taken immediately. Isolate infected individuals or groups and seek help from professionals for pathogen identification and diagnosis.
Author's point of view
A review of propagation and culture techniques of Protochoena cruzi shows that understanding and mastering the reproductive characteristics of Protochoena cruzi and appropriate culture techniques are the keys to successful farming.
Through reasonable water quality management, feeding management and disease prevention and control measures, the growth rate and production efficiency of Protochocera cruzi can be improved, and contribute to the sustainable development of the aquaculture industry. However, further research and practice are still needed to improve the propagation and culture technology of Protochovita cruzi to meet the market demand and the requirements of sustainable development.
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