The living habits and nutritional value of silver crucian carp (the daughter country among fish)

Silver crucian carp (Carassius auratus gibelio) is a closely related subspecies of crucian carp. Commonly known as: crucian carp melon seeds (Northeast), red crucian carp (Xinjiang Altay). English name: Silver prussian carp.

The body shape and color of silver crucian carp are very similar to that of ordinary crucian carp, but its body is significantly taller and wider than ordinary crucian carp, with its body length being 1.9-2.4 times its height; its body color is darker; its growth rate is faster than that of crucian carp, and its individual size is also larger. The largest individual can reach 3 kg.

The living habits of silver crucian carp are similar to those of crucian carp. It likes to live in shallow water, overgrown with aquatic plants, and places with muddy bottom. Overwinter in deep water. It is an omnivorous fish. The spawning period is generally from the end of May to the beginning of July. The age of first sexual maturity is mostly 3 years old, and a few are 2 years old.

Silver crucian carp is widely distributed in the temperate waters of Europe and Asia. my country is rich in the Heilongjiang-Liaohe River Basin in Northeast China and the Irtysh River Basin in Xinjiang.

Usually in the natural environment, the sex ratio of a fish is about 1:1. The ratio of ordinary crucian carp is 4:1, while that of silver crucian carp is 9:1. The reproduction method of silver crucian carp is also unique. They do not require a male mate, so how do their eggs fertilize and develop after they are laid? First, let’s explore it from a genetic perspective. Most fish have dozens to 100 dominant genetic chromosomes in each somatic cell, and are called diploid fish. The number of chromosomes in the eggs and sperm produced by these fish is reduced by half. This kind of sperm has , egg cells are called haploid. During fertilization, after the sperm enters the egg, a diploid fertilized egg containing 100 chromosomes is formed. The fertilized egg divides and develops, and its offspring are both male and female.

The somatic cells of silver crucian carp contain 162 chromosomes and are called triploid fish. The number of chromosomes in the eggs they produce remains unchanged at 162. The fertilization process of eggs during the reproduction of silver crucian carp is very special, which is different from the general fusion of the two sexes. The eggs produced by silver crucian carp are not stimulated by sperm produced by male fish of other species, but these sperm do not participate in the actual fertilization process and thus develop into female offspring. This special process of fertilization and development is called gynogenesis. Therefore, the offspring of silver crucian carp are exactly the same as their mother from external characteristics to internal structure, forming a unique "daughter country" of fish.

Scientists took advantage of the unique genetic characteristics of silver crucian carp and selected the sperm of Xingyuan red carp to inactivate the eggs of silver crucian carp. Their offspring are still all females, which not only maintains the mother's excellent genetic characteristics, but also exhibits " The advantageous traits of the "parent strip" are that the offspring will not separate, degenerate, and grow quickly. Its growth rate is 2-3 times that of ordinary crucian carp, and it has the advantages of wide feeding habits, easy raising, easy reproduction, strong vitality, few diseases, good meat taste, rich nutrition and high economic value. This kind of silver crucian carp is named Xieyu Silver crucian carp.

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