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Releasing fish fry in early spring requires care; keep these precautions in mind
Fish fry quality For fish fry of the same species and same age, the specifications should be uniform, with little difference in body length and body weight, thick back muscles, bright color, intact scales and fin rays, normal activity, and strong upstream-swimming ability. After being taken out of the water and placed in a basin, the gill covers should not open, the tail should not bend, and the fish should keep jumping, with no wounds or parasites on the body surface. Fish fry disinfection Some farmers do not disinfect fish fry at all when releasing them, resulting in a high disease rate, and drug treatment is not ideal. In fact, as long as fish fry disinfection is done well, disease prevention can often achieve twice the result with half the effort
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Yellow Catfish Polyculture Technology: Efficient Micro-net Cage Farming Method
Setting up micro-net cages in ponds used for farming other aquatic species to raise yellow catfish is a high-yield farming method that increases water surface utilization, featuring simple operation, low investment, easy rearing, fast growth and high returns. 1 Net cage setup The net cage is sewn from polyethylene netting, 2 m long, 2 m wide and 1.2 m high, with a mesh size of 0.5-1 cm. The cage uses a closed stretcher floating-fixed type, with a 9-mesh net cloth as a cushion layer at the bottom, the cushion layer edge being 20 cm high, to reduce feed loss; the upper part of the cage rises 30 cm above the water surface
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Guidelines for Fishery Reconstruction Measures After Rain, Snow and Freezing Disasters in Southern China
Since early January 2008, rain, snow and freezing weather has severely affected fishery production in multiple provinces and municipalities in southern China. According to incomplete statistics, losses from fish and shrimp killed by freezing in southern provinces and regions exceeded 10 billion yuan. In response, the following measures and suggestions for freshwater fishery reconstruction after rain, snow and freezing disasters in southern regions are proposed for reference. In terms of aquaculture species and regions, the current damage is mainly divided into the following types: 1. Tilapia aquaculture: The tilapia aquaculture industry suffered the most severe losses during this winter's cold wave.
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Detailed Explanation of the Preparation Method and Technical Key Points of Fish Scale Glue
1. Process flow: fish scales → washing → alkali soaking → acid soaking → lime soaking → rinsing → glue boiling → filtration → coagulation → glue scraping → drying → finished product. 2. Process steps. After washing, the fish scales are soaked in a 5% caustic soda solution for about 5 minutes to remove grease and fatty skin and to make the scales swell. The alkali-soaked fish scales are immediately rinsed with water, then soaked in clean water to remove alkalinity until phenolphthalein no longer turns red. Next, the cleaned fish scales are soaked in hydrochloric acid, with the amount used starting at 12% (hydrochloric acid volume concentration 31%), then gradually decreasing, 8%, 3%,
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Nine precautions for using fishery drugs in summer
Summer is a period of high incidence of fish diseases, and also a peak period for the use of fishery drugs. The following points should draw everyone's attention: 1. When two drugs are mixed for use, they should first be dissolved separately in water before mixing. Copper sulfate, ferrous sulfate, potassium permanganate, etc. should all be dissolved in water in a wooden bucket or wooden basin. Powdered drugs such as bleaching powder and trichlorfon should first be mixed with a small amount of water into a paste, then diluted with water, so as to prevent caking that may be mistakenly eaten by fish. The following drugs cannot be mixed: bleaching powder and quicklime, copper sulfate and quicklime, trichlorfon and quicklime. 2. Appli
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How to treat anchor worm disease in fish? A detailed explanation of nine treatment methods
Anchor worms are parasitic copepods that are very harmful to fish. The common anchor worms include four species: Lernaea polymorpha, Lernaea cyprinacea (carp anchor worm), Lernaea ctenopharyngodontis (grass carp anchor worm), and Lernaea quadrispina. Anchor worms can parasitize both young fish of the year and adult fish; they bore their heads into the host's muscles or under the scales, while the thorax and abdomen remain exposed outside the host's body. At the sites where anchor worms parasitize, needle-shaped pathogens are visible to the naked eye. If anchor worms parasitize a fish for a long time, the surface of the worm body often has protozoa and algae growing on it, appearing to the naked eye like a bundle of gray
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What kind of fish is the East Asian plateau loach? Characteristics and habits
Common name: Jiuerbang. Origin and season: Widely distributed in Qinghai, Tibet, Gansu, ** and western Sichuan. Description: Mouth inferior, relatively wide. Lips thick, upper lip wrinkled, lower lip with papillae and deep wrinkles, lower jaw spoon-shaped. Tips of pelvic fins extending backward to or beyond the anus. Caudal peduncle relatively high. Body surface smooth and scaleless. A bottom-dwelling fish, living in slow-flowing streams or shallow water with abundant gravel and aquatic plants, feeding on animal food. Individuals are relatively large; a specimen with a body length of 142 mm has been observed; numbers are abundant and can form regional
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What are the reasons fish frequently get sick?
In aquaculture practice, a phenomenon is often observed: species with strong disease resistance in the wild become prone to disease after living in aquaculture environments for a long time. The strength of a fish's disease resistance is mainly determined by its genetic factors, but whether it ultimately becomes ill is determined by the environment. Various stimuli from the environment to fish are called environmental stress factors. In aquaculture ecosystems, the stress that fish experience is often caused by environmental factors such as non-ionized ammonia, dissolved oxygen, pH, and water temperature. Generally speaking, aquac
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Methods and Techniques for Processing Silver Carp and Bighead Carp into Fish Balls
Silver carp and bighead carp, two of the "Four Major Chinese Carps," have many intermuscular bones and a flavor slightly inferior to other fish, so they often sell poorly, making the problem of processing and utilizing silver carp and bighead carp urgent to solve. Below is an introduction to the method of using silver carp and bighead carp to process and make fish balls. Auxiliary ingredient formula: based on 50 kg of fish meat, 1 kg of salt, 3 kg of starch, 0.5 kg of granulated sugar, 0.075 kg of monosodium glutamate, an appropriate amount of ginger juice, and a water content generally 50% to 60% of the fish meat weight. Key operating points: select
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What are the methods for identifying the quality of fish fry?
Buying high-quality fish fry is the key to improving the survival rate. The quality of the fry can be judged by indicators such as body color, activity, and sampling inspection. Body color: high-quality fry have the same body color as a group, with clean bodies and no mud clinging to them; poor-quality fry vary in body color as a group, commonly known as mixed-color fry, and their bodies carry mud. Activity: stir the water holding the fry into a whirlpool; most high-quality fry swim against the current at the edge of the whirlpool; most poor-quality fry are drawn into the whirlpool. Sampling inspection: blow on the water surface; if they can move against the wind and current, and after the water is poured off
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