Animal Gummy Candy, Sweet Gummy Candy,Sour And Sweet Gummy Candy,Chewy Gummy Candy Montreal Shantou Food Co., Ltd , https://www.montrealsnack.com
Umbellaria is a highly valuable freshwater fish, known for its significant economic and nutritional benefits, making it a popular choice among consumers. In recent years, the breeding and large-scale cultivation of Umbellaria have seen rapid development, with particular emphasis on the production of high-quality seedlings. This article provides an overview of the key techniques involved in the breeding and cultivation of Umbellaria seedlings.
**I. Selection and Cultivation of Broodstock**
The best time to collect broodstock is during September, though selection can also be carried out in late March or early April. It is recommended to choose wild or farmed black buckwheat that is at least two winters old, with a weight range of 0.75–1.25 kg. The selected fish should be healthy, free from disease, and without any injuries. They are then placed in a dedicated pond, with one pair per 10 square meters. Before introducing the broodstock, the pond must be thoroughly cleaned and disinfected, and the fish themselves should be treated with a disinfectant solution. A 1:1 male-to-female ratio is ideal.
As spring approaches, water temperatures gradually rise to around 15°C, and feeding begins. Initially, feed should be limited to about 1–2% of the fish’s body weight, with gradual increases as conditions improve. Once the fish are acclimated, they enter a more intensive care phase. To stimulate gonad development, a regular water flushing technique is used, combined with daily feeding at 6–8% of their body weight. By May, when the temperature exceeds 20°C, spawning typically begins.
**II. Artificial Breeding of Broodstock**
Artificial spawning of Umbellaria is commonly conducted between May and June. Female fish should exhibit a swollen, soft abdomen, with visible ovarian outlines and a noticeable central groove, along with a protruding genital opening. Males should display a deep purple-red body color, with dorsal fins featuring neatly arranged white spots from bottom to top—more spots indicate better quality.
A common method involves a single thoracic injection. The dosage is 6 mg DOM + 15 mg LRH-A per kg of female body weight, while males receive half that amount. Spawning can occur in hatching tanks, concrete pools, or earthen ponds, with hatching cylinders offering the best results. After cleaning and disinfecting the incubator, fresh water is added, and the fish are treated with 1 ppm malachite green. A small amount of water peanuts is placed in the nest. Once injected, the broodstock is introduced into the incubator in pairs, covered with a fine mesh to prevent escape. Water flow can be controlled using a waterstop or microfluidic system. At 22–23°C, spawning takes 27–35 hours, while at 24–25°C, it lasts 24–30 hours. Spawning occurs in quiet, low-light conditions; disturbances can cause the fish to stop spawning. Eggs are typically collected 12–14 hours after spawning starts, with unfertilized eggs removed and the remaining eggs transferred to an incubator.
**III. Artificial Hatching**
Fish eggs can be hatched in hatching cages (40 cm × 100 cm × 50 cm) using a microfluidic method, with approximately 10,000 fertilized eggs per cage. Alternatively, they can be hatched in hatchery pools (3 m × 4 m × 0.8 m), holding 40,000–50,000 eggs per pool. The hatching rate depends on the fertilization rate and water quality. Key considerations include preventing water mold, maintaining clean water, handling eggs gently, and avoiding sudden temperature changes.
**IV. Seedling Cultivation**
While egg production and hatching are relatively straightforward, raising fry is challenging, labor-intensive, and has a low survival rate. Even minor mistakes can lead to losses.
**Larval Rearing**
After 4–5 days, larvae begin feeding on zooplankton smaller than 200 μm. Small, frequent meals are used initially, increasing in number over 3–4 days before reducing to twice daily. During this period, clustering and “red worm†infestations may occur, so gentle water agitation helps improve survival. Unfertilized eggs and remnants should be removed regularly, and water should be changed daily. Aquatic fungi and protozoan parasites must be controlled. By day 5–6 (or 9–10 days post-hatching), fry grow to 1–1.4 cm, developing a more complete respiratory system and increased activity, indicating they can eat normally. As they grow, rearing density should be reduced, and they are moved to summer fish species cultivation.
**Summer Fish Species Cultivation**
Summer fish species can be raised in concrete tanks, typically measuring 4 m × 3 m × 0.8 m, equipped with intake and drainage systems, aeration, and feeding tables. A plastic greenhouse above the tank helps maintain stable environmental conditions, protecting against direct sunlight and rain. Stocking density ranges from 400–500 fish per square meter in ponds, and up to 1000 fish per square meter in microfluidic systems. Newly hatched fry are fed live zooplankton, and once they reach 2 cm, they can also consume dead zooplankton. If needed, yeast protein, fishmeal, or wheat flour can be mixed into stagnant water. Feeding should be done in small portions to maximize survival. Regular water quality monitoring and oxygenation are essential.
When fry reach 3–4 cm, they can be transferred to larger pools or cages for further growth.