How much do black-spotted frog seedlings cost? Detailed guide to breeding methods
The black-spotted frog is an amphibian of the genus Pelophylax in the family Ranidae. It lives an amphibious life on land and in water, emerging after dusk and at night to move about and hunt. During the tadpole stage it is omnivorous, and as an adult it feeds on insects. It weighs 50-60 grams, with the largest individuals weighing around 100 grams. In China it is distributed across all provinces and regions except Hainan, Yunnan, and Taiwan, China. Let's take a look below at the prices of black-spotted frog seedlings and the breeding methods!
How much does one black-spotted frog seedling cost?
The price of black-spotted frog seedlings is about 0.03-0.05 yuan each, but prices vary greatly depending on the size, quality, place of origin, and market of the seedlings. The reproductive season of the black-spotted frog is from April to July, with the peak of egg-laying in April. Eggs are mostly laid in seedling fields, early rice fields, or other still-water areas, and occasionally in slow-flowing water. Each egg mass contains 2-3.5 thousand eggs, mostly floating on the water surface, and the tadpoles complete metamorphosis in about 2 months.
Breeding conditions for the black-spotted frog
1. Temperature: The suitable growth temperature for the black-spotted frog is 20-30°C. When the temperature drops below 10°C, feeding and activity gradually weaken; when it drops below 5°C, hibernation begins; when the water temperature exceeds 32°C, activity clearly weakens; and when the temperature exceeds 35°C, the black-spotted frogs will die one after another.
2. Humidity: The skin of the black-spotted frog has no tissue structure to protect against evaporation of body moisture, and relying only on mucus secreted by skin glands to maintain skin surface humidity is clearly insufficient. Therefore, the habitat must have both ponds with water and a warm, humid environment overgrown with weeds.
3. Light: The black-spotted frog hides by day and comes out at night, fearing direct sunlight but tending toward weak light. Light promotes metabolism, growth, and reproduction in frogs. If kept in darkness for a long time, their gonads struggle to mature, and they may even stop laying eggs and releasing sperm.
4. Water quality: Black-spotted frog tadpoles require relatively high dissolved oxygen in the pond water, generally meeting fishery water quality standards. Although adult and young frogs breathe with lungs, high dissolved oxygen in the water still has a good effect on them. A pH of 7-8 is suitable, and salinity generally should not exceed 2.
Breeding methods for the black-spotted frog
1. Pond construction: Black-spotted frog breeding ponds are divided into spawning ponds, tadpole ponds, and adult frog ponds. Generally, a humid, warm, and shaded location should be chosen, with a long cement pond or earthen pond being suitable. A shade board must be installed over the pond surface, and floating aquatic plants should be placed in the pond water.
2. Selection of breeding frogs: For black-spotted frog breeding stock, choose frogs that have gone through a second spawning. Second-spawning breeding frogs have a relatively high fertilization rate. Although female frogs in their third and fourth years lay a large number of eggs, the fertilization rate is poorer, and first-year frogs also have a relatively low egg hatching rate.
3. Spawning time: Black-spotted frogs lay eggs every year from March to July. Spawning is later in the north, while in the south egg-laying begins in March, with April being the peak spawning period. However, amplexus, mating, and spawning of breeding frogs are greatly affected by air temperature, the water temperature of the breeding pond, and water depth.
4. Collection of egg masses: After the fertilized eggs of the black-spotted frog are collected, place them in the disinfected ring ditch of the breeding pond to hatch. The darker side of the egg mass is the animal pole and must face upward, while the whiter side is the vegetal pole and must face downward.
5. Hatching management: During the hatching period of the black-spotted frog, the water temperature must be kept between 20-25°C. If the water temperature suddenly rises or falls by more than 5°C or there is strong disturbance, the frogs may die. Two days after hatching begins, the frog eggs can shake slightly; in 3-4 days they take on tadpole form; and in about 5 days small tadpoles hatch.
6. Tadpole rearing: After black-spotted frog tadpoles hatch, they are raised in the original hatching pond or in net cages, with 600-800 tails per square meter of water surface. For the first 4-5 days they generally do not eat anything and mainly rely on their own yolk sac for nutrition. After the yolk sac disappears on the 4th day, artificial feeding begins.
7. Young frog rearing: Black-spotted frog young frogs are kept at 100-150 per square meter. A feeding platform is set on the water surface without land, forcing the young frogs to come onto the platform to feed and rest. First feed them live bait for 1-2 days, then increase the proportion day by day, and finally transition to completely artificial feed.
8. Adult frog rearing: After young black-spotted frogs are transferred to the adult frog pond, their food intake is large and their growth speed accelerates, so animal-based feed needs to be increased. After 1 month of rearing, when they reach 100 grams, keep 30 per square meter; after 2 months, keep 10-15 per square meter; after a further short period of rearing, they become commercial frogs.