Intensive quick-raising technology in special pond of giant salamander

Dazhu, commonly known as baby fish, also known as salamander, pike and quadruped fish, is a large-scale amphibian unique to China. Its meat is tender and delicious, and it is very rich in nutrition. it is a tonic for banquet delicacies and parturients, the old and young and the weak. its meat and skin are used as medicine to treat anemia, neurasthenia, liver and stomach pain, joint pain, dysentery, diarrhea, burns and other diseases.

Under natural conditions, due to the late sexual maturity of giant salamander, low reproduction rate, and many changes in geology and geomorphology in history, the ecological environment of giant salamander has been seriously damaged, and its wild resources have been increasingly exhausted. The Chinese government listed giant salamander as a second-class protected animal in 1989. Therefore, artificial breeding of giant salamander can not only protect and proliferate giant salamander resources, but also meet the needs of domestic consumers and export foreign exchange earnings.

In recent years, the results of domestication experiments show that giant salamander can quickly adapt to the artificial ecological environment and grow rapidly under the condition of sufficient food. In this paper, the intensive quick-raising technology of giant salamander is introduced as follows:

Pond construction

The giant salamander breeding pond should be built in a quiet, cool environment with abundant water resources and good water quality, and the water temperature should be in the range of 10 ℃ ~ 25 ℃ all the year round. If there are conditions, it is best to be equipped with facilities for heating in winter and cooling in summer, which is helpful to improve the feeding effect.

The main contents are as follows: 1. The juvenile pond is mostly made of cement, with an area of 8 square meters to 10 square meters, a height of 50 centimeters to 60 centimeters and a water depth of about 20 centimeters. The bottom of the pool should be covered with a layer of sediment, the wall of the pool should be smooth, and there are stone piles, rockery, islands and anti-escape boards on the edge of the pool for young salamanders to climb onto land to prevent escape.

2. Chengyi Pool: the cement structure is mostly adopted, the area of each pool is 50 ~ 70 square meters, the height of the pool wall is 1.2 ~ 1.3 meters, the shape of the pool is rectangular, and the water inlet and outlet is set up, and the water depth is kept at about 30 cm. A hole is built around or in the middle of the pool bottom, and bricks and cement boards can be used as materials. The cave is rectangular box-shaped, with a height of 15 cm ~ 20 cm, a depth of about 50 cm and a width of 30 cm ~ 40 cm. Under the condition of artificial feeding, giant salamander often live in one hole, so the hole width can be seen and the feeding scale is expanded accordingly. The inner wall of the cave should be flattened with cement mortar to make it smooth to avoid bruising the giant salamander. A habitat platform can be set up in the middle of the pool for giant salamander to move on it. The surface of the pool should build a shed or plant trees and melon beans on the pond bank to protect the giant salamander from the scorching sun.

Seedling stocking

The suitable stocking density is beneficial to the growth of giant salamander and reduce the feed coefficient. The production practice has proved that 25 ~ 30 young salamanders and 10 ~ 15 adult salamanders with specifications of 500g / tail ~ 1000 g / tail can be released per square meter of water. Stocking specifications should be neat, so as not to cause the law of the jungle due to differences in individual size. The newly built cement pool must be soaked in water for 15 ~ 20 days, and only when the pH value of the pool water is stable below 8 can the seedlings be released. One week before stocking, both new and old ponds should be disinfected with bleach or other drugs to kill enemy organisms. Soak the seedlings with 0.2 grams of furan or 0.5 grams of pentamethyl blue in water for 5 minutes before the seedlings are planted in the pond.

Bait feeding

During the feeding period, young salamanders are mainly fed with live baits such as chironomid larvae and water earthworms. After 15 days of feeding, you can properly feed some shrimp, earthworms, minced meat, etc., and bait at night. Feeding for about 8 months, when the young salamander weighs more than 20 grams, the bait can be fed with minced fish or chopped beef, mutton, etc., or can be fed with artificial food. The growth rate of young salamander was 33.3% faster than that of fresh diet when fish meal and α-starch were used as main raw materials and the content of crude protein was 42.3%-45.6%.

Adult salamanders can be fed with fresh low-value fish or artificial bait (reference formula: fish meal 55%, withered cake 8%, wheat bran 5%, silkworm pupa 5%, bone meal 1.2%, α-starch 17.3%, premix 8.5%). If live fish are used, the bait fish should be cut into pieces and fed. Artificial formula feed is generally powdered and can be adjusted into a soft ball with water before use. Fresh animal offal can also be used as bait for salamander after being cooked in boiling water, but its nutritional value is not as good as that of fresh fish and artificial bait. Generally, the daily feeding rate of fresh bait is 10%-15%, and the artificial compound feed is about 10%. Bait is generally placed in the water, usually around dark in the evening. In the range of suitable temperature, the adult salamander has the most food intake within 3 hours after dark, and when the weather is muggy, the food intake decreases significantly, or even stops eating. Therefore, the specific feeding time and amount should be flexibly controlled according to the weather, water temperature, water quality and the activity of adult salamander.

Daily management

The intensive fast culture in the special pond of giant salamander has high stocking density and the water quality is difficult to balance naturally. Therefore, the young salamander pond should change the new water once a day, and clean up the residual bait in the pool, so that the transparency of the pool water can see the bottom at a glance, and the pH value is kept between 6.5 and 8.5. In general, the water is changed once every 2 to 3 days and once a week in winter. The specific times of changing water should be determined according to the air temperature and water quality, so as to keep the water quality fresh. Always check the feeding pond to prevent the giant salamander from escaping. No matter young salamanders and adult salamanders, after entering the pool, they should record the air temperature, water temperature, bait species, feeding amount, eating, growth and activities every day, in order to sum up and accumulate experience and further raise giant salamanders.

Disease prevention and treatment

Giant salamander has strong stress resistance and is generally disease-free. However, the disease prevention and treatment of giant salamander should be strengthened because of its high density, more bait and fast growth. In the process of feeding, the mixture of copper sulfate and ferrous sulfate (5 ∶ 2) was sprinkled once a month to kill bacteria and parasites in the pond. If the giant salamander has skin ulcers or bites, it should be caught immediately for isolation, feeding and treatment. Penicillin can be injected 50,000 international units / kg, once a day for 4 consecutive days, and then once every 4 days. 2 ~ 3 times in a row can be cured.