Black herring, known as the first of the four major fish, is one of the main species of pond culture in China. Black carp culture is mainly distributed in the plain areas south of the Yangtze River, such as Anhui, Hubei, Huzhou, Zhejiang and Wuxi, Jiangsu, with less culture in the north of the Yangtze River. In Anhui, herring is commonly known as snail mixed, black mixed and black mixed. In Zhejiang, commonly known as black pomfret and snail green, they are named after their black bodies and their love for snails. Because herring has thick back meat, tender meat, short fiber and few thorns, a large number of herring are listed in Jiangsu, Zhejiang and Shanghai after the winter solstice every year, which requires a large specification of 8 kg. The bigger the specification, the higher the price. Large-scale herring is generally processed into pickled fish, which is a necessary dish for Chinese New Year gifts and high-grade banquets.

Herring is the only species of the genus Herring, which is slightly cylindrical and large in size. Black herring mostly inhabits the middle and lower reaches of the water, belonging to a mild carnivorous fish. Under natural culture conditions, snails and bivalve mollusks, small fish, shrimps and aquatic insects are the main species. At present, artificial breeding is the main method, and herring special compound feed is the main method. When the length of herring reaches 15cm, the crushing function of pharyngeal teeth will be enhanced, and the feeding habits will also change. The growth rate of herring is fast, and the fish of 2-3 winter age can generally reach 7- 10 kg. The largest herring ever recorded was caught in Jinniu Lake, Liuhe District, Nanjing. It weighs 265438 08 Jin and is 65438 0.86 m long. It was identified as about forty years old.

First, herring culture mode

Black carp culture is mainly based on main culture and large-scale polyculture, among which Huzhou, Jiaxing and Xiantao are the representatives of main culture mode.

The main feeding methods of herring are herring and crucian carp. Among them, the black herring is generally put in at 300-350 fish/mu 0. 1 kg, which can reach about 3 kg at the end of the year, and can be used as the breeding seed of the big black herring in the next year; Carassius auratus is mainly used as bottom adjustment fish, and silver carp is mainly used as water adjustment fish.

The polyculture model of herring is complex, and the polyculture varieties are mainly grass, crucian carp and bream, but there is no obvious regularity. Generally, the farming mode is adjusted according to local farming habits and the trend of fish prices in that year.

Second, the choice of herring feed

2. 1 Selection of herring feed varieties

(1) Earlier, herring culture was mainly based on granular compound feed. After the promotion of puffed materials in recent years, farmers in Huzhou, Wuxi Ganlu, Hubei Xiantao and other markets have realized the benefits of puffed materials, and basically used puffed materials special for herring.

(2) At the beginning of March-April and in the low temperature period after 10 every year, herring does not feed on the water surface, and farmers mainly use granular materials, but the consumption ratio is low throughout the year; When the water temperature reaches above 18℃ (from late April to early October), farmers automatically switch to herring puffed material.

(3) Enteritis is the most harmful to herring in the early stage of culture (March-June). Because the intestines of herring after the "hunger strike" in winter are thin and brittle, Huzhou farmers generally choose low-grade herring feed in the early stage and control the feed at the same time to prevent the spread of herring enteritis. After entering July, high-grade puffed herring was fed in large quantities, and the specifications of herring were quickly raised. But as a formulator, this feeding method is not desirable. It is more reasonable to keep the reasonable feeding rate of herring, prevent enteritis, and carry out health care work such as intestinal nursing in the early stage. At the same time, the formula of herring feed in the early stage will also be adjusted in a targeted manner, such as adding prebiotics to maintain the balance of intestinal colonies and using digestible raw materials to reduce the pressure of intestinal digestion and absorption.

2.2? Suggest a reasonable feeding rate

The feeding rate of herring is adjusted according to the change of water temperature and different specifications.

2.3 Black herring's choice of swelling material particle size

In the process of culture, according to the nutritional requirements of herring in different growth stages and the changes of herring specifications, combined with the adjustment of production technology (crushing fineness), the puffed materials with different particle sizes are reasonably selected. According to the suggestion of Tongwei Fisheries Research Institute,

Third, herring feed grade.

The protein content of puffed compound feed for herring from most manufacturers in the market is between 30% and 34%. It was found that as long as the protein was above 30%, the optimum growth demand of herring could be met, and excessive protein had no obvious effect on the growth of herring. What matters is the digestibility of protein and amino acids. Shaoxing Tongwei 8 153#, Shaoxing Tongwei 8 155# and Hefei Tongwei 155# puffing materials are designed to meet the nutritional needs of herring and are special puffed compound feeds for herring. Their main nutritional indicators are

Fourthly, the performance of herring feed effect

In Huzhou and other areas, in the intensive culture mode of herring, the net yield of herring per mu is more than 2000 kg, and the feed consumption per mu is generally about 2 tons. There are many herring feeds on the market, and the breeding coefficient recognized by farmers is 4.5. The feed length is 1 (the feed coefficient is about 1.8).