The artificial breeding of river crabs in Rudong County, Nantong, Jiangsu Province is well-developed. However, in the early stage of cultivation of early crabs, the fertilized eggs showed a phenomenon of “climbing.†The specific performance is as follows: When the water temperature rises to 15°C, it can be observed through a microscope. It was found that the development of the surface egg and the inner layer of the crab was not synchronized, but this time it was not obvious. When the temperature was raised to 18°C, the development of the surface layer and the inner layer of the fertilized egg was extremely out of synch and the internal egg development lags behind. The surface eggs differ from the internal eggs by more than 7 days, and there are even a large number of dead eggs. It also shows that when the eggs are discharged, the color of the eggs is purple, rather than normal gray. When the larvae are released, they have a large number of unabsorbed yolks. This kind of larvae is difficult to cultivate, the elimination rate is high, and the whole Disease during the nursery is more. I. Cause Analysis 1. The crabs do not have proper mating water temperature Nantong area. Natural temperatures in winter have been high in recent years. The natural water temperature in mid-November is still above 12°C. Nursery planters grow at more than 12°C for early emergence. The mating of crabs under the condition of water temperature will increase the chance of repeated mating and reduce the quality of fertilized eggs. 2. The holding crabs do not undergo low temperature stimulation. The holding time of the eggs is short and the water temperature is not enough. The crabs will be mated in mid-late November and pick up eggs and crabs by early December. The incubation time before warming is very short, only about 20 days. At this time, the natural water temperature is also around 5°C to 9°C. The fertilized eggs do not pass through. The low temperature below 3°C stimulates and there is no sleep time, resulting in inconsistent temperature in the inner and outer layers of the egg, which results in the development of the egg not being synchronized. Second, the basic strategy 1. Select the appropriate mating crab water temperature, with 9 °C ~ 11 °C as well, species of crabs mating about 7 days, timely pick out the holding crabs and some crabs, improve egg quality and mating rate. 2. According to the actual temperature and water temperature conditions in Nantong, it is better to extend the cultivation time of the crabs in the natural water temperature, and it is better to be more than 40 days, so as to avoid rushing to warm up and produce for early emergence. 3. The conditional farmer can place the species of crabs on the coastal areas of northern Jiangsu or Hebei. The water temperature in these places has dropped to about 15°C in late October. The temperature of normal mating water can be reached in early November, and in late December. The water temperature in the early January to the following year can reach around 0°C. This will provide enough cold stimulation and incubation time to ensure that the accumulated temperature required for egg development will ensure the developmental synchronization of the fertilized eggs.