Contents
1. Living habits
2. Morphological characteristics
3. Distribution range
4. Breeding technology
5. Processing and production
6. Nutritional value
Living habits
Bullfrog is a kind of temperature-changing animal, which lays eggs all its life, hatches them into tadpoles and lives in. Cattle like to live by the ditch and pond. If there are floating plants on the water, they will lie on the water, put their heads out of the water, and dive into the water when disturbed. Bullfrogs often live in groups of several or dozens, and generally do not migrate after adapting to the environment. From April to September every year, bullfrogs begin to lay eggs in pairs. The fertilized eggs hatch into tadpoles in 3-4 days, live in water and breathe through their gills. After becoming a young frog, he lived an amphibious life. When the water temperature drops below 1℃ in winter, bullfrogs hide in caves or mud and go into hibernation. When the temperature rises above 1℃, come out for food again.
bullfrog is a temperature-changing animal, and its body temperature changes with the change of external temperature. Under natural conditions, the survival temperature of tadpoles is 2-35℃; The most suitable water temperature for growth and development is 23-25℃; When the water temperature exceeds 35℃, tadpoles will die one after another. When the temperature is below 15℃, tadpoles will not eat. When the water temperature is lower than 9℃, it goes into hibernation. The suitable temperature for adult frogs to feed and grow is 2-3℃, and the optimum temperature is 25-3℃. When the water temperature drops below 18℃ in autumn, appetite and activity are weakened; Stop eating below 15℃; Hibernation began at 9-1℃. When the water temperature exceeds 32℃, the activity and feeding are obviously weakened, and when the water temperature exceeds 35℃, bullfrogs die one after another.
bullfrog skin has no protective tissue to prevent water evaporation, so it can't leave water for a long time, and it can die in dry air or in the sun for too long. The skin temperature directly affects the reproduction and ovulation of bullfrog, and the growth and development of tadpoles need to be carried out in water, so water is an indispensable ecological need for bullfrog. Bullfrogs are generally photophobic, nocturnal, and like to live in a sunny environment conducive to growth, development and reproduction. But avoid direct sunlight, prefer weak light to blue light.
tadpoles of bullfrogs feed on organic scraps and zooplankton, while young frogs and adult frogs feed on some aquatic and terrestrial animals. When hunting, choose a safe, secluded and bait-rich shallow water or land, wait patiently, and when the prey is found alive, jump and catch it by pouncing. When you are far away from the frog, you gently climb to the target and wait for an opportunity to catch it. In the absence of bait, bullfrogs eat too much and eat too little.
Morphological characteristics
The body shape is the same as that of the general frog, but the individual is larger, with the female frog being 2 cm long and the male frog being 18 cm long, and the largest individual can reach more than 2 kg. The head is wide and flat. Mouth-end position, nose-end sharp and round. The exophthalmos of eyeball is divided into two parts: upper and lower parts, and there is a crumpled instantaneous membrane on the lower eyelid to close the eye. The back is slightly rough and has fine skin edges. The limbs are stout, the forelimbs are short and webbed. The male individual has an obvious gray tumor-like process on the inside of the first toe. The hind limbs are long and big, with webbed toes. The skin color changes with the living environment, usually the back and limbs are green-brown, with dark brown stripes on the back; The head and mouth are bright green; The ventral surface is white; The color below the throat varies from male to female, and females are mostly white, gray or dark gray, while males are golden yellow. The singing is very loud, and it is named after Niu Jiao.
distribution range
It is native to North America. In 1959, it was introduced into China's inland from Cuba and Japan. At present, China mainly relies on aquaculture production, which is produced all over the country, mainly in Hunan, Jiangxi, Xinjiang, Sichuan and Hubei. HDPE geomembrane can be selected for seepage control of farm land. Commercial frogs are mainly in autumn and winter, and the supply sources are mainly from Guangdong and Fujian.
aquaculture technology
The pond selection requires sufficient water source, convenient irrigation and drainage, pollution-free water quality, quiet environment, convenient transportation and sufficient power supply. The frog pond is built as a big pond every 1 square meters, and each big pond is divided into four small ponds on average. The edge of the pond is surrounded by 4-mesh screen silk, the screen silk is about 1 meter higher than the bottom of the pond, the bottom of the screen silk is 2-3 cm buried in the soil, the ridge of the pond is 4 cm high, the slope ratio of the pond is 1: 3, the water level is 3-4 cm, and the water depth is not less than 2 cm.
The water inlet and outlet are set at the opposite corners of the big pond. Four 8cm and 4cm foam plastic plates are placed in each pond as the rest platform for bullfrogs, and the black sunshade net is used for shading.
stocking seedlings
Before releasing seedlings, disinfect each mu with 5-75 kg of quicklime or 1-15 kg of bleaching powder. Seedlings can be released 1 days after disinfection in the pond, and the young frogs are soaked with 2 mg/L potassium permanganate solution for 1~2 minutes before stocking. Stocking density: 6~8 frogs/m2 in the juvenile stage and 3~4 frogs/m2 in the adult stage.
feeding management
(1) patrol the pond for inspection. Patrol the pond once a day in the morning, at noon and at night to prevent bullfrogs from escaping. The running water is guaranteed to be uninterrupted for 24 hours, and the water change rate reaches 3% every day. The water level can be controlled by the rise and fall of plastic intubation at the drain outlet. Generally, the water depth of the pond is 3~4 cm. Take timely measures when finding abnormal feeding and activity of bullfrog.
(2) The feed is mainly floating compound feed. Soak the compound feed with water half an hour before feeding to promote softening and swelling. The daily feeding amount is 7%~15% of the total amount of frogs in the pond, and it should be adjusted according to the climate, water quality and residual bait, and the feeding amount should be eaten within half an hour.
(3) Graded breeding, i.e., individuals with larger specifications are screened in time at regular intervals, and bullfrogs with similar specifications are adjusted to the same pond for breeding.
disease prevention
Before stocking the fry, clean the pond with quicklime or bleaching powder to kill harmful organisms and pathogens, and regularly spray the whole pond with bleaching powder or strong chlorine essence for disinfection, and then disinfect the frog body with 2mg/L potassium permanganate solution after dividing the pond to prevent mechanical damage. Found that sick frogs and dead frogs were picked out in time and kept in isolation, and disinfected with high concentration bleaching powder or potassium permanganate solution in time.
processing and making
dry pot bullfrog
Ingredients: one catty of bullfrog, potato, lettuce, coriander, dried pepper, onion ginger, garlic, dried starch, salt, white pepper, Sichuan spicy sauce, pepper, soy sauce, cooking wine and sugar
Practice:
1. Wash bullfrog and cut into pieces.
2. Peel potatoes and lettuce and cut them into strips respectively, and cut parsley and onion into sections; Remove the coat from the garlic, peel off the garlic and slice the ginger.
3. Put the bullfrog into a bowl, add a little salt and pepper and marinate for 15 minutes.
4. put enough oil in the hot pot, fry the potato chips with low fire until the heat reaches 6%, and then take them out for later use.
5. pat some dried starch on the pickled bullfrog, fry it in an oil pan until it is slightly yellow, and take it out for later use
6. pour the excess oil out of the pan, leaving a little base oil, and add onion, ginger, dried pepper, pepper and garlic to saute.
7. Stir-fry a tablespoon of Sichuan beef hot sauce or other hot sauces, add lettuce and potatoes, stir-fry slightly, add appropriate amount of cooking wine, soy sauce and sugar to taste, add the fried bullfrog, stir-fry quickly and evenly, and sprinkle with parsley.
pickled bullfrog
ingredients:
5g of bullfrog, 15g of scallion, 2g of salad oil, 1g of cooking wine, 1g of pickled ginger, 1g of refined salt, 15g of scallion, 2g of monosodium glutamate, 15g of pickled red pepper, 1g of pepper and 2g of dried bean powder.
Production method:
1. Slaughter bullfrog, remove its head, skin and viscera, wash it, cut it into pieces, and size it with salt, pepper, dried bean powder and cooking wine. Soak red peppers, remove pedicels, remove seeds and cut into sections, wash green onions and cut into sections, soak ginger and cut into ginger rice.
2. Heat the oil in the wok to 7% heat, and take the bullfrog out of the wok. Heat a little oil in the wok, add ginger rice and pickled pepper to stir-fry for fragrance, add bullfrog, cook cooking wine, add monosodium glutamate and scallion, turn the wok and put it on the plate.
raw fried bullfrog
first prepare a bullfrog, bamboo shoots and green peppers. Kill the bullfrog and cut it into pieces. Boil it first, then swing it out (to get rid of blood) and then pour a little oil into the pot. Add ginger slices and bullfrogs. Stir-fry Add green pepper and bamboo shoots. Stir-fry less Just add a little yellow wine and half a spoonful of water. Then add salt, monosodium glutamate, a little sugar, and pepper. When the water is halfway down. Just add some starch, pour sesame oil out of the pot, and it's ready.
nutritional value
bullfrog is rich in nutritional value and delicious. Every 1 grams of frog meat contains 19.9 grams of protein and .3 grams of fat. It is a nutritious food with high protein, low fat and low cholesterol, and is loved by people.
Bullfrog also has nourishing and detoxicating effects. People with poor digestive function or hyperacidity and people with weak constitution can be used to nourish the body. Bullfrog can promote human vitality, energy, nourishing yin and strengthening yang, and has the effects of nourishing heart, calming nerves and invigorating qi, which is beneficial to the rehabilitation of patients.
The viscera and offal of bullfrog are rich in protein, which is hydrolyzed to produce compound amino acid. Among them, the contents of arginine and lysine are high, which is a good food additive and tonic. Hydrolyzed compound amino acid, separated and purified, is used in medicine and cosmetic industry. The endocrine system of bullfrog secretes various hormones, which can be used in medicine, industrial production and scientific research after extraction. For example, pituitary hormones are used as artificial oxytocin for fish and amphibians, which is beneficial to artificial reproduction. The stomach gland, intestinal gland and pancreas of bullfrog are rich in digestive enzymes, especially those that hydrolyze protein, which can be extracted and utilized. The bile of bullfrog is extracted and processed for medicinal purposes. Frog skin can be used as an excellent raw material for making surgical lines. Frog oil can be used to make high-grade lubricating oil.