Barbs, which have the advantages of wide appetite, rapid growth, delicious meat taste, less disease, and high adult fish prices, are popular among the people and are an excellent new breeding breed. At present, some units organize scientific and technical personnel to conduct artificial propagation tests. In recent years, the author explored the broodstock culture of Barbodes (Spinibarbus) caldwelli and Barbodes (Spinibarbus) denticulatus donticulatus (hereinafter collectively referred to as barbs) and tentatively explored some experiences. ,for reference.
First, the significance of broodstock cultivation Broodstock breeding is a very important part of artificial reproduction. The development of broodstock has a direct impact on the maturity of the gonads, the productivity of the gonads, the fertilization rate and the hatching rate of the eggs, and therefore must be taken seriously. The pros and cons of gonad development are directly related to feeding and management. Feeding and management methods can obtain broodstock with well-developed gonads; conversely, feeding and management are not allowed, and gonad development is not good. The entire broodstock breeding process is a process of creating conditions that transform the gonad gonads into maturity. Therefore, the method of broodstock cultivation must be in accordance with the basic rules of the gonadal development of fish, and a large number of high quality broodstock with high maturity rate should be cultivated.
Second, the broodstock cultivation pool conditions and clearing broodstock cultivation pool is the environment of broodstock life, pond conditions such as location, area, bottom quality, depth, etc., will directly or indirectly affect the growth and development of broodstock. Therefore, serious choices must be made. 1. The condition of the broodstock pond: The location of the broodstock should be close to the water source, sufficient water supply, convenient irrigation and drainage, fresh water, no pollution, transparency above 50cm, pH 7-8.5, dissolved oxygen above 5mg/L, better water flowing pond , an area of ​​3-5 acres, the water depth of 1.5-2 meters above, to the east and west to the long, north-south width of the rectangular pool is better for easy feeding and management and fishing. The bottom of the pool is flat, free of silt or less silt. 2. Clearance of broodstock culture ponds: The clearing of broodstock ponds is a non-negligible task in broodstock breeding. It must be carried out once a year, and it must be completed after artificial breeding is completed. The contents of the clean-up work include excavation of excessive silt at the bottom of the pool, maintenance and reinforcement of ponds, removal of weeds, removal of wild fish, etc., to create a good environmental condition for broodstock, which is conducive to the growth of broodstock and development of gonads.
Third, broodstock breeding
1. Stocking density and male-female ratio: 40-50 tails of broodstock with 2-4 kg of broodstock per acre, and another tail broodstock with 3-4 broodstock and grass carp. The average stocking weight per mu is about 150 kg. The ratio of male to female is 1:1.5-2, and the minimum is not less than 1:1.
2. Breeding method: “Fine material, green material combined with feeding, regular flushing†is an effective way to cultivate barbs and pro-fish. Concentrates are mainly formulated feeds; greens are vegetables, lettuce leaves, perennial ryegrass, black leaf algae and so on. Postpartum cultivating: During this period, the water temperature is relatively high, broodstock ingests food vigorously, and the daily feed of concentrate feed is about 2% of the fish's body weight. The feed is also fed with green feed. Feeding is carried out in accordance with the "four determinants" and regular removal of sloping rot.
Autumn and Winter Breeding: As the water temperature decreases, the broodstock ingestion intensity gradually decreases, so all the fine material is used during this time. Feeding amount is about 1.2-1.5% of fish weight. When the water temperature is low, the feed can be stopped, and when the water temperature is high, feeding can be performed every other day. Feeding time is from 9-10 am, feeding at the next 2-3 points. Put the feed on the food table. The food table sinks to the bottom of the water from the shore and cleans the food table regularly. Spring Breeding: After the spring, the “old water†of the pond should be replaced by about half, and new water should be added to keep the water depth at about 1 meter to improve the water quality, increase the water temperature, and facilitate the barb feeding. After the water temperature rises, the fish eats increasingly and the gonads are in a large growth period. During this time, feed must be given. If the feeding is insufficient, the gonadal development is not good and production cannot be induced. After March, try to feed young feed such as wheat seedlings, lettuce leaves, and perennial ryegrass as early as possible. At this time, mainly green feed should be used, supplemented by concentrated feed, to avoid excessive accumulation of fat in the fish body, affecting gonad development and spawning. At the time of oxytocin production, the amount of barb trophozoites was significantly reduced or stopped feeding, indicating that the gonad gonads are mature and can be artificially elicited. Care of post-partum broodstock: Nursing care after spawning by broodstock is a work that requires attention in production. Because broodstock is often injured during oxytocin production, broodstock will die if not properly cared for. After nursing the broodstock after spawning, first of all, the over-fatigue broodstock should be placed in a fresh water pond to allow them to fully rest and feed finely, so that they can quickly restore their physique and increase their resistance to the bacteria. In order to prevent the infection of broodstock wounds, postpartum broodstock may be strengthened for disease prevention measures, wound dressings and antibacterial drugs. Adding fresh water to keep fresh water is one of the important technical measures to promote the development and maturation of gonads in broodstock. Barb, broodstock due to long-term artificial feeding, a lot of feed residue and feces is very easy to make the water become fat, will make barb broodstock food intake decreased; and due to residual baits, feces and other decomposition of oxygen, can easily cause pan pool, Cause broodstock death. Therefore, in the process of barb bred bred fish, it is necessary to pay attention to frequent flushing, especially flushing water before spawning, in order to maintain the water quality is relatively fresh. Flushing should be based on the season, water quality, and broodstock feeding. Generally, the water temperature in winter is low, and the number of flushing can be less, flushing once every two weeks or one month; flushing every three to five days when hot, flushing water for 3-5 hours each time, so that the water level rises by 20 Centimeters or so. About half a month before labor, the number of flushes must be increased. It is best to flush once every 1-2 days. A few days before spawning, it is best to flush water every day. Conditioned ponds provide better water stimulation. Flowing water is extremely important for the development of gonads in certain fishes. The four stages of development of the gonadal gonads require different ecological conditions. Phase II, III nutrition, water quality and other conditions are the main flow of water stimulation does not seem to be the main factor. However, when it develops to stage IV, it is important for the water flow stimulation to further develop and mature the gonads. For example, during the spawning season, during the spawning season, the brooding fish completes the transition from stage IV ovary to stage V during the spawning season when heavy rains approach, flash floods, and water levels skyrocket, causing turbulent water flow. Spawn immediately. Some reservoirs upstream, the rapid flow of water, the fish can also lay eggs. This may be a change in ecological conditions, in particular the stimulation of flowing water, which promotes the synthesis and release of large amounts of hypothalamic LRH, triggers the secretion of gonadotropins by the pituitary gland, and subsequently induces their estrous spawning. Barbed broth broodstock due to long-term artificial feeding, a large number of residual baits, feces and other decomposition, consumption of large amounts of oxygen in the water, coupled with broodstock large amount of eggs, oxygen consumption increased, in the warmer weather, temperature rise, the water temperature rises faster, in In the sweltering morning, pans often occur, causing broodstock deaths (especially for females with well-developed gonads that are more likely to die). Therefore, from March-April onwards, special management is needed to start the patrol pond and discover the pan-pool omens (the weather is boring, the pressure is low, the transparency is reduced, and shrimp fish swim to the shore), and new water should be flushed to prevent flooding. Pool. Post-harvest summer and autumn seasons, when thunderstorms and sweltering depressions occur, flooding pools must also be prevented.
Zhang Shuibo, Fishery Technology Promotion Station, Zhangzhou City, Fujian Province