The breed knowledge of silkworm
Silkworm varieties are generally divided into three categories:
1. Univoline silkworm varieties
Silkworm because breed is different, produce one generation to lay diapause egg inside a year only call a sex silkworm breed. This variety develops slowly, after a number of days, larval mulberry eating a large amount, silkworm body and cocoon shape is also large, silk most, but weak constitution, high temperature and humid climatic conditions are not adapted, suitable for breeding in temperate regions.
2. Divoltine silkworm varieties
The second generation occurs in one year, that is, the first generation produces non-diapause eggs, and the second generation produces diapause eggs. This variety has shorter larval period than univoline variety, stronger constitution and regular development, only cocoon layer is slightly inferior to univoline variety. Most of the current varieties are improved by introducing excellent cocoon silk properties of univoline varieties, which are suitable for raising silkworm in warm zone and summer and autumn.
3. Polychromatic silkworm varieties
The silkworm varieties with more than three generations in a year are called polychromatic silkworm varieties, while some of the last generation produce diapause eggs and some still produce non-diapause eggs. The former are called polychromatic silkworm varieties with diapause period, and the latter are called polychromatic silkworm varieties without diapause period. This variety develops quickly and the larval stage lasts for a very short time. Body is very strong, cocoon shape is small, silk quantity is small, cocoon silk fineness is fine, separated fine fiber is small, silk quality is slightly poor.
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Biyang donkey
Produced in Henan Province, the central producing area is in Biyang County, so it is called Biyang donkey. Biyang donkey is a medium-sized donkey with a strong physique, square shape and symmetrical development. it is similar to Guanzhong donkey in appearance, but more meticulous than Guanzhong donkey. He is about 1.25 meters tall and weighs 220-250 centimeters. The coat color is mainly pink and black. It is estimated that there are about 25000 horses in existence. Biyang donkey maximum pull 203.3 kg, load 100-150kg, daily travel 40-50 km, 3 donkeys pull load 1500 kg rubber-wheeled cart, daily travel 35-40 km. Slave, meat and meat at the same time
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Breeding and processing of snakes
Snake is a precious biological resource. Snake edible, pharmaceutical, piano and so on, the whole body is covered with treasures, known as "Shanzhen". Snakes sell well and sell at a high price. The domestic purchase price per kilogram of live snake and snake meat is 40,000 yuan, the purchase price of five-step snake is 250,000 yuan per kilogram, the price of one gram of bungarotoxin is 1000 yuan, and the price of raw snake bile is as high as 2000 yuan per kilogram. The price of 5 grams of snake venom in the international market is as much as 1000 US dollars, which is 20 times more expensive than gold. The period of artificial breeding snake is short and the benefit is high, so that farmers can shake off poverty and become rich.
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