Is the temperature in Lanzhou suitable for grass carp farming?

The temperature in Lanzhou is suitable for breeding grass carp. Grass carp has a simple feeding habit, a wide range of food sources, rapid growth and high yield, so it is often used as the main stocking target for pond culture and lakes, reservoirs and rivers. Since the success of artificial induction of labor and fertilization and hatching technology in 1958, fry and fingerlings have become easy to source and have become the main targets of intensive breeding in my country.

Pond requirements: The pond area is preferably 10 to 20 acres, the water depth is 2 to 2.5 meters, and the silt thickness does not exceed 20 cm. Each 10 acres of pond is equipped with one aerator and one automatic feeding machine each with a power of 3 kilowatts;

Pond cleaning: drain the pond water in winter and freeze and dry it for more than 20 days. Fifteen days before the fish fingerlings are released, 10 to 20 centimeters of water should be introduced into the pond, and 150 kilograms of quicklime per acre should be used to clear the pond for disinfection; 300 grass carp species, 300 crucian carp species with a size of 15-20/kg, 50 silver carp species with a size of 5-6/kg, and 10 bighead carp species. Before stocking the fish, soak and disinfect them in 5% salt water for 5 to 10 minutes;

Feeding: mainly feed pellet feed, with a protein content of 28-32%, supplemented by green feed. Feeding follows the principles of "coarse first and fine second" and "four determinations and four observations". It is generally fed twice a day. It is advisable to eat it within 2 hours and make the grass carp 80% full. After continuously feeding pellet feed for a period of time, the pellet feed should be stopped for 1 week, and raw grain feed should be fed during the interval. Pay attention to adding an appropriate amount of vitamins and other medicines to the feed to prevent grass carp from suffering from diseases such as hepatobiliary syndrome and causing a large number of deaths;

Water quality management: use the aerator correctly, on sunny and windless days from June to October, every day Turn on the machine and add oxygen for 2 hours from 1 to 3 pm, and add oxygen at the right time in the early morning; on consecutive cloudy days, add oxygen in advance. Add new water to the pond in a timely manner, and adopt the method of "small discharge, small inlet, and multiple water changes" to gradually control the water quality. From June to September, add new water every 3 to 5 days, about 10 centimeters each time. Every 15 to 20 days, use 10 to 20 kilograms of quicklime to slurry the entire pool at a depth of 1 meter per mu of water surface. ;

Disease prevention and control: adopt the feeding method of "combination of roughness at the beginning and fineness at the end, fineness and greenness at the end" to control the occurrence of grass carp hepatobiliary syndrome. Common diseases of grass carp include red skin disease, gill rot, and enteritis. Treatment methods generally adopt a combination of oral administration and external application. The external application mainly uses disinfectants such as bleaching powder and chlorine dioxide for 3 days; oral administration uses "three yellow powder". "The effect of medicinal bait is better. For every 50 kilograms of fish weight, use 0.3 kilograms of three yellow powders (50% rhubarb, 30% cork, and 20% skullcap, crushed into powder and stirred). Mix it with flour paste and mix it into the feed. , used continuously for 3 to 5 days;

Timely fishing: Timely catching and listing large-sized adult fish is an important measure for high-yield grass carp breeding. The main purpose is to reduce the fish load of the pond water body and promote the rapid growth of pond fish in the later period. grow. Catching is usually done once at the end of July, in the early morning when the water temperature is low.