The juvenile and juvenile stages are artificially divided. At room temperature, due to the hibernation habits of turtles, juvenile turtles generally refer to the first two months of the hatching year and the summer of the following year, and most of the young turtle stages begin from the third year. Under warmed conditions, the rearing of juvenile and juvenile turtles is from hatching out of the shell to April to May of the following year, and the two stages are continuous and there is no interval. The ecological habits of juvenile and juvenile turtles are very similar to the requirements for breeding and management conditions, so they are comprehensively described to avoid repetition.
<h1 class = "pgc-h-arrow-right" > (i) the temporary rearing of juvenile turtles</h1>
Newly hatched shelled juvenile turtles are susceptible to diseases, especially water mold and waterphilic aeromonas. therefore. Newly hatched juvenile turtles need to be washed and disinfected with 1%o potassium permanganate solution for 15 min. In view of the long spawning period of brooding turtles, there are early and late, early laying eggs, in July to August can hatch juvenile turtles, at this time the outdoor temperature is higher; late eggs, until around September can hatch juvenile turtles, morning and evening temperatures are lower. It can be seen that the hatched juvenile turtles should not be directly placed in the outdoor juvenile turtle pond to be raised.
Even if the temperature is suitable, because the juvenile turtle is delicate, do not directly put it into the juvenile turtle pond to be raised, it needs to be temporarily raised for a period of time, and after the yolk sac is absorbed and the fetal membrane is shed, then transfer to the temporary pond or enter the juvenile turtle pond. A pot with a diameter of 40 cm can temporarily raise about 20 juvenile turtles. The part that enters the nursery pond is usually juvenile turtles ready to be sold or transported. There is no unified regulation on the temporary pond, it is best to repair it indoors, generally less than 0.5m deep, no more than 1m wide, self-determined, the pool is slightly inclined, there is an inlet and drainage outlet, and it is a long tank that can adjust the water depth arbitrarily. Some aquatic plants are stocked on the surface of the water for the juvenile turtles to conceal and purify the water quality; and some wooden planks are placed as bait tables and for the juvenile turtles to rest. The water depth in the shallow water area is 2 to 5 cm in the initial stage of the temporary pond or the juvenile turtle pond, and the deep water area is 10 cm or so, and it is stocked according to about 100 animals/m2.
Before the baby turtle is temporarily raised, the utensils and the temporary pond should be disinfected. The newly built cement temporary pond should be soaked in water for two weeks, during which the water should be changed several times to make its pH meet the requirements. The tools that have been used are disinfected with quicklime water, bleach powder and other drugs before use, and the juvenile turtles are soaked with antibiotics, salt, furacillin and other solutions.
Juvenile turtles that have opened their mouths to feed should be baited in time. There are two types of bait: artificially matched bait and fresh bait. Fresh bait is best for water fleas (red worms), which can be fished from ponds or artificially cultured with idle water surfaces, and then collected and fed with nets. It can also be fed mosquito larvae, mealworms, silk earthworms and so on. The utilization rate of live fresh bait is high, the residual bait is small, the water quality is easy to control, and the turtle grows fast. At the beginning, the fresh water fleas are scattered into the water, fed for 3 to 5 days, filtered out the water, and placed in a ball on the board of the water surface of the temporary pond to bait and rest, and later can be fed surimi, shelled shrimp and mashed snail meat, pork liver, etc. The amount of live fresh bait is 10% to 20% of the weight of the juvenile turtle, which is fed twice a day, and then gradually changed to artificial bait.
The full-price artificial combination bait is used as a juvenile turtle opening bait, which has the advantages of comprehensive nutrition and easy to use. It can be used as a special bait for baby eels or juvenile turtles, with a protein content of more than 50%. Processed into 2mm granules. Or knead the vegetable juice into a paste and feed it. Using combined bait, the daily amount of bait is 4% to 6% of the weight of the juvenile turtle. After 1 to 2 weeks of careful temporary rearing, the juvenile turtle completely enters the normal feeding state, and the body color also becomes a shiny black brown, and then turns into a formal rearing stage or transportation of the juvenile turtle.
<h1 class = "pgc-h-arrow-right" > (2) the breeding methods and production levels of juvenile and young turtles</h1>
1. Heated aquaculture
The heating culture of turtles is mainly in the stage of juvenile and juvenile turtles. Although heating aquaculture consumes a certain amount of energy, the overall benefit is high. First of all, the warming culture breaks the law of turtle hibernation, and the entire breeding time is shortened by about 2/3; secondly, the heated culture can make the juvenile turtles weighing less than 50g safely survive the wintering danger period, thereby greatly improving their survival rate; According to the growth law of turtles, the growth is slow within 50g, and 200~500g is the growth advantage stage, such as the cultivation of about 200g of turtle species in April and May of the following year through heating, and rapid breeding is possible. At present, 80% of the juvenile and juvenile turtle culture in Japan is heated, from hatching out of the shell to April of the following year, most of the individual weight reaches 150 to 200g, and these turtle species can fully reach the commercial specifications after more than half a year of feeding. Therefore, if China wants to develop the breeding industry of turtles, the stage of juvenile and young turtles should be heated as much as possible to provide enough large-scale turtle species.
2. "Warming at both ends" culture
"Two-end heating" means heating in the early and late wintering of juvenile and juvenile turtles to shorten the overwintering period. The breeding method is heated before and after the severe winter with higher temperature, and when the temperature is extremely low, the juvenile and young turtles hibernate overwinter, which not only prolongs the growth period of the juvenile and juvenile turtles, increases the weight of the juvenile and young turtles, but also satisfies the habit of hibernating, and also greatly improves the survival rate relative to the normal temperature overwintering, saving the cost of heating, and is a breeding mode worth promoting.
3. Culture at room temperature
Under normal temperature conditions, before wintering, the weight of the hatchling turtles in the early stage is only 10 to 20 g, while the late hatching is only 3 to 5 g, which is less adaptable to adverse environments. Overwintering outdoors for several more months often has serious consequences: weight loss of 10% to 15%, mortality rate of up to 70% to 80%. After the recovery of surviving juvenile turtles, it is difficult to return to normal, which directly affects the next stage of breeding. Therefore, the overwintering of juvenile turtles at room temperature should be carefully managed, and where there are conditions, it is best not to use room temperature for wintering.
<h1 class = "pgc-h-arrow-right" > (3) the rearing management of juvenile and juvenile turtles</h1>
The three months after hatching are critical periods for survival. Therefore, its breeding management is the most important stage in the whole process of turtle rearing.
1. Bait and feeding
Entering the formal rearing stage of juvenile and juvenile turtles, under the conditions of suitable water temperature (30 °C), the growth speed and survival rate depend to a large extent on the bait. The bait of juvenile and juvenile turtles is required to be thin, soft, refined and tender, easy to digest and comprehensive in nutrition. The bait of juvenile and juvenile turtles is divided into fresh bait and artificially matched bait. Fresh bait should be adapted to local conditions, according to the conditions of the times, both subject to various conditions, such as autumn biological bait (water fleas, etc.) can not be guaranteed, but also has the defect of insufficient nutrition. Large-scale production should be mainly based on matching bait, supplemented by fresh bait.
There are commercially available juvenile and juvenile turtle special baits, requiring a protein content of more than 50%. Because the combination of bait in the production process of more use of defatted fishmeal, so in the feeding must add 3% to 5% of vegetable oil, and the combination of bait and fresh minced fish meat in a 1:4 ratio, and then add 1% to 2% of vegetables, rolled into a lump or made into soft particles of bait, put on the bait table. For juvenile and juvenile turtles, fresh food with high fat or indigestible, such as pig intestine, silkworm pupae, meat powder, etc., should not be fed as much as possible.
The feeding requirements for juvenile and juvenile turtle bait are required to achieve "four certainties": the bait must be placed on the bait table and rest platform near the water level; the morning and afternoon feeding twice; the quality is adjusted according to the above requirements; the daily bait volume of juvenile and juvenile turtles is generally 3% to 5% of their body weight (dry matter), usually two hours after feeding.
2. Timely grading feeding
Turtle spawning period is very long, successive batches of eggs produced, hatched hatched turtles individual size is also uneven, stocking density is higher, individuals are easy to interfere with each other, plus even if homologous, homogeneous individuals, after a period of time of feeding will soon appear size differentiation, some individuals difference of 10 to 20 times. Therefore, in order to prevent mutual biting, the juvenile and juvenile turtle stages must be implemented from the beginning. Medium and small are graded according to specifications and raised in separate ponds.
Under the conditions of heated breeding, the hatching of juvenile turtles needs to be continuously fed according to individual growth and individual differences, with the purpose of continuously adjusting the density of juvenile and juvenile turtles, so that the unit water body always maintains a more suitable load, and individuals with more consistent weight are raised in the same pool, which can accelerate their growth. At this stage, more than three feedings are required, and a variety of preparations are required before feeding. Such as ponds, tools and turtles with disinfectant drugs, feeding plans, etc. The feeding needs to dry the pond to release water, wash away the sludge, turn the pond sand, and manually capture. The operation should be fine, the action should be fast, and the turtle should not be injured. The caught turtles are quickly placed in a container filled with water, then disinfected and transferred to a prepared pool in different sizes.
3. Temperature control
For heated aquaculture, no matter which stage of breeding, it is necessary to maintain a water temperature of 30C soil (1 ~ 2) C, and a temperature of 33 ~ 35 C. Hot water and steam can be used for pool water heating, and heat dissipation devices are used for indoor air heating. Before each use of the greenhouse, various heating equipment, temperature control devices, etc. should be completely overhauled to ensure that there is no failure during use. In the process of breeding, temperature changes are monitored at any time and adjusted in a timely manner.
The growth of juvenile and juvenile turtles is positively correlated with the average daily water temperature. According to the domestic study on the growth of juvenile turtles (Cui Xiqun et al., 1991), when the water temperature is 30 °C, the fastest growth, the daily weight gain of individuals is 0.226g, when the water temperature drops to 21C, there is almost no weight gain in feeding for 35 days, and the temperature difference is only 3'C when the water temperature drops from 30C to 27C, while the daily weight increase drops by 50%. This shows the importance of water temperature regulation. In practice, both heating and cooling should be gradual, so that turtles have a process of adaptation; sudden heating or cooling will cause metabolic disorders, resulting in death.
4. Water level and water exchange
The water depth of the juvenile turtle pond is generally 30 to 50 cm, and the water level gradually deepens as the young turtle grows up, and the water depth range is usually 50 to 80 cm. Regular water changes are the main measures to improve water quality. The factors that affect the water quality of turtle ponds are the deposition of residual bait and excreta to produce methane. Toxic substances such as hydrogen sulfide and ammonia nitrogen. Especially in the late stage of wintering and heating, it is necessary to strictly prevent the deterioration of water quality, considering the heat loss and cost, the water should be changed 3 to 4 times a week. And pay attention to increase light and ventilation. If you think that the whole animal is breathing with lungs, it is wrong to think that the water quality is good or bad; the pond water as the habitat of the turtle, the quality of the water will directly affect the survival and growth of the turtle.
5. Water quality regulation
The ponds are small, shallow in water storage and have a large stocking density. In particular, warming breeding, while creating a superior breeding condition for turtles, also deepens the vicious circle of the environment: insufficient sunlight→ high temperature→ high density → strengthened bait → residual bait and excreta deposition - + deterioration of water quality. Even if the water is constantly changed, as the feeding time is extended, the effect of each water change will be reduced more and more each time. Proper lighting is essential to regulate water quality. Light allows algae in the water to multiply, replenish oxygen in the water, decompose organic matter, and maintain relatively stable water quality. Light is indispensable for the whole sunbathing habit, and a greenhouse without sufficient light is not an ideal greenhouse.
In order to regulate water quality, the use of circulating filtration devices and mechanical oxygenation are also important measures. The regular (10 ~ 15d) alternating use of lime and bleach powder, disinfection of pool water and improvement of water quality, is a recommended, economical and simple method at home and abroad. It can not only improve water quality, but also prevent disease. In addition, aquatic plants such as water lotuses and duckweeds are stocked in juvenile and juvenile turtle ponds, which also have the functions of improving water quality and providing a hidden place for juvenile and juvenile turtles.
The above is the artificial rearing technology of juvenile and juvenile turtles, and it is recommended to collect them.