Efficient Technical Methods for Breeding Toads in Rice Paddies

The toad is a highly valuable amphibian and reptile used for both food and medicine. The toad skin (chan yi) that it naturally sheds and the milky secretion (chan su) collected and processed from its post-auricular glands are precious traditional Chinese medicinal materials. With the depletion of wild resources, artificial breeding is imperative. Using rice paddies to raise toads offers complementary advantages and can form a well-functioning cycle of a natural food chain. The relevant technical points are briefly described as follows.

Field and pond setup: Choose a relatively quiet field plot with convenient drainage and irrigation. Surround the rice paddy with 0.8 m high dense nylon netting, with an inner width of 1.5 m along the embankment to allow the toads to come ashore and move about, and install netting at the water inlet and outlet to prevent the toads from escaping. On one side of the rice paddy, right against the embankment, dig an additional small pond for raising tadpoles; the pond area should be no less than 1/6 of the total area. If the breeding rice paddy is too large, it can be divided into several small ponds. The pond water depth should be 40 cm, and a water injection pipe with a diameter of 1 cm should be set up above the pond. Set a water outlet on any side of the embankment and surround it with polypropylene netting. A mesh of 60 openings per square cm is suitable.

Tadpole stocking: First use 15 kg of quicklime for dry pond clearing of the small pond. After 7 days, fill with water. Add 100 kg of fermented organic fertilizer to the pond. After 5 days, put the tadpoles into the pond. When stocking, choose uninjured, robust tadpoles of uniform size. After disinfection in 1.5% salt water, stock them at 6000 to 8000 tails per mu of rice paddy. The air temperature at stocking should not be lower than 20%.

Toad pond management: While ensuring a slight flow of water in the small pond, simply keep the water quality from deteriorating under the effect of leftover bait. When feeding, it is best to feed small amounts many times, using floating powdered self-mixed feed, until metamorphosis. After the young toads complete metamorphosis, set up a circular feeding platform with a steel wire mesh bottom in the center of the small pond, and feed live bait (earthworms, fly maggots, etc.) as well as floating pellet feed every day. At the same time, when feeding, add water through the injection pipe to set the floating pellet feed in motion, so as to train the young toads to feed. At the beginning, the proportion of live bait is relatively large, then gradually decreases. After the young toads have developed the habit of feeding at fixed points, the net enclosure of the small pond can be opened and the young toads released into the rice paddy to forage freely.

Field management: After the young toads enter the rice paddy, keep the field water relatively clear in the early stage. In hot summer, the field should be frequently irrigated with "horse-running water" to regulate water temperature and water quality. In addition, if disease occurs in the rice, pesticide spraying should be done on sunny days, with the nozzle facing upward and the mist fine, so as to avoid the pesticide sinking as much as possible. Once pesticide deposition in the field becomes too concentrated, immediately add water to regulate it. Under normal circumstances, no pesticide needs to be applied, because toads have the ability to catch pests. In the field, young toads must be protected from natural enemies such as snakes and hawks. Toads generally do not become ill under natural conditions, but attention should be paid to mechanical bruises that cause external wound infection. Therefore, special care must be taken when catching them, and only cloth bags may be used to catch them. Two months after the young toads are released into the rice paddy, screen them once a month thereafter, catching the large ones and leaving the small ones. After catching, place them in dedicated breeding ponds so as to collect toad skin and toad secretion, or to sell them.