Weed Mat,Plastic Rope & Net,Other Horticulture & Gardening Products Plant Support Net,PE Tarpaulin Co., Ltd. , http://www.nbmetalnet.com
Feeding technology for fish with compound feed
With the increase of aquaculture level, the compound feed for fish is generally accepted, and the feed amount per unit of aquaculture area is increasing year by year. At present, the cost of feed in many ponds accounts for 70% of the total culture cost. 80% It is very important to improve the feeding technology of fish feed, improve feed utilization, and reduce waste. 1 Factors affecting fish feeding and digestion Factors affecting fish feeding include: environmental factors (such as water temperature, dissolved oxygen, water quality), physical factors (such as the exchange rate of water, culture methods), and management factors (such as feeding rate and feeding frequency). 1.1 Dissolved oxygen The amount of dissolved oxygen in water has a great influence on fish intake, feed digestion and absorption and fish growth. The amount of dissolved oxygen in the water is low, the appetite of the fish is poor, or the anorexia is poor. The digestion and absorption rate of the feed after eating is low, the growth rate is slow, and the feed coefficient is high. Some data show that when the fish grows at the optimal temperature, the dissolved oxygen in the water is less than 3.5mg/L, and the feed coefficient above 3.5mg/L is increased by 1 time. Yu Qingming test pointed out that grass carp oxygen dissolved in water 2.5. 3.4mR/L than 7.0.9.0mg/L feed coefficient to increase 1.34 times, 35.9% reduction in food intake. When the water temperature of the carp is 20-30Y, it is necessary to ensure normal feeding and growth. The oxygen content in the water should not be lower than 4.0-6.0 mR/L. When the amount of oxygen in the water is 2.0, 0.5 mg, the diet of salmon will be reduced by half. Long-term exposure to such low oxygen conditions can cause growth to stop and even reduce weight. When the amount of dissolved oxygen in the water reaches 4 mg or more, the appetite of the fish increases and the feed digestibility increases. Therefore, when feeding, attention should be paid to the amount of dissolved oxygen in the water and changes in the weather. The amount of dissolved oxygen in the water is low, the fish floats its head, and it is generally not fed. After the dissolved oxygen in the water is improved, it is fed. Normal weather in pond culture is normal. After about 2 hours of sun exposure (at 9.1 o'clock), the dissolved oxygen in the pond water can reach 4 mg/L or more. At this time, the feeding effect is better. 1.2 Water temperature Fishes are hypothermic animals. Water temperature has an important influence on the fish's feeding intensity. Within the appropriate temperature range, the increase of water temperature has a significant effect on the ingestion intensity of farmed fish. As the water temperature decreases, the fish's metabolic levels also decrease, leading to loss of appetite and growth. The main fish cultured in China, such as green, grass, chain, system, pupa, threshing, and other fish, are wide-temperature fish, and have a wide range of adaptation to water temperature, and can survive in 1.38Y water temperature, but suitable The growth temperature is 20-32Y. The squid grows fastest when the water temperature is 25-30 Y g. When the water temperature drops to 15 Y, the growth is inhibited. If the water temperature falls below 13Y, the activity of foraging is greatly reduced. Above 13Y, when the temperature is increased by 10Y, its food intake increases 2-3 times. Grass carp had the highest level of metabolism at 27.30Y and the highest ingestion intensity. When the water temperature drops to 20Y, its growth rate decreases significantly. At the water temperature of 17Y, the intestinal filling index of grass carp decreased by 10% compared to 21Y. 2 Feeding Technology The correct and reasonable feeding method is conducive to improving the feed utilization, reducing waste, reducing the feed coefficient, and improving the efficiency of aquaculture. Feeding techniques include determining the optimum amount of feed, number of feedings, time of feeding, and feeding method. 2.1 Determination of the amount of bait to grasp the most appropriate amount This is the key and core of feeding technology. Overfeeding causes waste and can pollute the water and cause illness. The lack of feeding can not meet the energy and nutritional needs of fish, so that fish can not maintain weight and reduce production, also caused a waste of food. Using the best food, the best growth rate and population yield is the optimum amount of feed. The amount of feed per year can be calculated based on the feed's feed coefficient and the expected output: Feeding amount = feed ratio throughout the year) (Predicted net production monthly feed amount = annual feed amount monthly allocation ratio after calculation of annual feed amount According to the distribution ratio of each month, the daily feeding amount is determined according to the weight, size, and water temperature of the pond fish. Every 10 days, adjust the amount according to the weight gain of the fish. Daily reference feeding amount = total body weight of the fish (Respective water temperature and specifications) Reference feeding rate Feeding rate is the number of feeds (kg) per 100 kg of fish per d. Factors affecting the rate of feeding are colored specifications, water temperature, dissolved oxygen in water and feeding management, etc. The rate rises with the increase of water temperature at the appropriate temperature, and decreases with the increase of the fish size.The reference feeding rate of the fingerling stage is approximately 4% of the fish's body weight. 6%, the coloring stage daily reference feeding The rate is about 1.5% of the eating fish weight, and 3% of the weight of the feeding fish.2.2 The amount of daily feeding is adjusted according to the season, weather, water color, and fish feeding conditions.(1) Feeding conditions of the fish The amount of fish is generally eaten to 70% or 80% full (most of the fish eat and walk, only a small amount In the surface layer, bait tests have proved that whether the individual or the group controls the “eight-point fullness†of the feeding amount is more conducive to keeping the fish’s strong appetite and improving the feed utilization rate than the “full-saturation†of the feed-in and bait. 2) The weather is fine. The dissolved oxygen in the water is high. The fish should eat well. It should be suitable for many shots. On the contrary, the weather is hot, continuous rain, the water has low dissolved oxygen, and the fishes have poor appetite. If the water quality is deteriorated, less or no investment should be made.(3) Water quality in the pond The fish is a respiratory animal in pupa and oxygen is a limiting factor in aquaculture. The level of dissolved oxygen directly affects the growth and feed efficiency of the fish. Refreshing, fish ingestion is strong, should be more vote; water quality is not good, too fat, too strong, fish loss of appetite, and residual baits are easy to make water worse, should be less investment; water quality is bad, the fish has been floating head, should be prohibited (4) Water temperature in ponds The food intake of fish is significantly affected by changes in water temperature. Within the range of moderate temperature, the increase of water temperature has a significant effect on the feeding intensity of farmed fish; the water temperature decreases, and the fish’s metabolism declines. ,resulting in If the water temperature exceeds 8Y, it begins to ingest.When the water temperature exceeds 8Y, it begins to ingest.Begins to grow above 10Y, and before and after the beginning of spring, it starts to ingest food. Before and after Qingming, the food intake increases with the increase of water temperature, but the food intake decreases when the temperature exceeds the suitable temperature. Reduce the amount of feeding (5) The feeding season during the breeding season should grasp the feeding rules of “early open food, catch the middle, and bring two endsâ€, and concentrate the feed for the whole year mainly on the 6. September fish ingestion. The most prosperous and fastest-growing season investment is to advance as early as possible before April, and after October, it is necessary to prolong the feeding and stop the food before harvest so as to ensure that the fish does not fall out. Local feed resources, such as cultivating grasses, mothers, and spinning fish, are rich when grass is rich, and part of grass is fed, while some species of snails and warships can be fed, but they cannot be fed at the same time as full-priced feeds. The success or failure of ingestion and domestication is related to the utilization rate of feedstuffs and the economic benefit of breeding. When other conditions are basically the same, three different feeding methods are adopted: throwing mud from people, setting up water in the water, and feeding on the surface. Coefficients were 2,1.7,1.5. This group of figures shows that for every 1,000g of grass carp weight added, 2000g of feed is required for withdrawal into the mud method, and only 1500g of feed is required for surface domestication, and 1.8 yuan per 1000g of feed. The latter is more economical than the former. 90 yuan, female D fruit 666.7 into a net 600kg of grass carp fish, male p what 666.7IJ (mu) surface can save feed costs 540 yuan. Domesticated fish populations can increase their feed intake according to the fish's diet. Therefore, domesticated fish should be fed upstream to catch food. Feeding points are convenient for transporting feed, water depth is about 2m, and it is easy to prevent theft at night. Feed the feed at a fixed position every day and use a wooden board to extend the springboard about 3m into the pool for people to sit or place a feeding machine to prevent the fish from destroying the fish pond and avoiding the fish crowding, so that the fish can feed on a wide range evenly. In the upwelling sunny side of the middle of the fish pond, a simple bait station was set up, and a domesticated fish colony was used to snare in a fixed position upstream for 1 week. A few days before the normal feeding, use half-starvation. Before domestication began to feed, first use water splashing or knocking on the barrel to make a sound to stimulate the fish, then withdraw a small amount of pellet feed and repeat every 10 to 10 seconds. Each training should be 20. 30 min. Domestication work must be patient and meticulous. Whether or not the fish eats food, insist on it. After 1 week of domestication, the fish can easily cause conditioned reflexes and gradually develop habits of fixed-point floating colonies. The use of expanded material can save the domestication of fish, save labor and reduce waste. Specialized aquatic products (yellowhead, yellow mullet, black mullet) expanded feed domestication method: the first extrudate is soaked with fish slurry (after washing with fresh bait and washed with gauze) and then gradually reducing the amount of fresh bait fish slurry until Domestication is successful. This process takes about one week. After successful domestication, it is forbidden to feed fresh bait. The extruded material can be soaked with fresh water first, so as to avoid ingestion of filthy water when the feed is directly fed, causing gastrointestinal inflammation. 2.4 The feeding method must be patient and careful when feeding. When feeding the feed, it should be done as soon as possible that feed into the water can be quickly eaten by the fish. Do not feed the feed once to the pond. This will cause the feed to be lost without being fed by the fish, resulting in low feed utilization. One by one, the feed should be withdrawn into the water. The fish quickly gather together and concentrate on the surface of the water to catch food. The water splashes and then disperses the water to feed. Water patterns appear on the water. The big fish first compete for food and small fish compete for food. From intense to slow, when the fish is full, they will walk away. Feeding should be based on the principles of “invading, fast, slow†and “less, more, and lessâ€. When feeding is started, feed slowly with a small amount of feed, and increase the amount of feed when the fish are trapped together to catch food. , speed up the frequency of feeding, so that most of the fish have eaten slowly walk, and then reduce the amount of feeding, slow feeding frequency, and finally stop feeding. The feed should be withdrawn by hand one by one and the radius of the cloth removed should be more than 1m. The feeding speed should be coordinated with the feeding speed of the fish, and each feeding should continue for 20.30m:n. With the development of intensive fish farming and the popularity of pellet feed, bait feeders can be used in places where conditions permit, so that the fish can feed evenly, but they still need to be guarded by people, so that they can keep abreast of the situation of fish feeding and adjust the speed of feeding. How many. The puffed fish feed method adopts fixed-point feeding and is fixed into squares or triangles with bamboo, and the puffed feed is put into it. For the stormy waves, the reservoir can be used to enclose a bait. The mesh is 50cm high, 25cm above the water surface, and 25cm below the water. It is fixed with bamboo. 2.5 Feeding frequency The fish breeding stage is divided into 4.5 feedings and the adult fishing stage is divided into 2-3 feedings. The smaller the fish size, the more feeding times. Each time interval 3. 4h, the interval should be uniform. Adult fish ponds are generally bred at 9:10 a.m. and at 16.17 a.m. each time, and on rainy days no more than 18 o'clock. Baiting should be performed at a suitable daylight temperature (20.32Y). When the temperature of water is 32Y, the feeding time should be postponed. In the morning, if the floating head should be normal, it should be baited after 1. 2h. The breeding of foot fish needs to increase the number of feedings, which generally takes 5.6 times or more times per day.