The purchase of high-quality crab seedlings is an important guarantee for the success of breeding. Practice has shown that the same quality of crab seedlings in different culture conditions, the difference is not obvious, and the decisive factor that really affects the survival rate of the first phase of juvenile crab is the quality of crab seedlings, good Seedlings are crucial prerequisites for successful crab farming. High-quality crab seedlings have the following main characteristics, we should strive to grasp: The "three-see-one sampling" method can be used to judge the quality of crab seedlings. (1) See if the specifications are the same. The size and size of the same batch of crabs must be neat and consistent, generally requiring 80-90% of the same, otherwise it will be more likely to cause fratricide in crabs or juvenile crabs in the 3-5 period when the rearing age is low. . (2) See if the body color is the same. High-quality crab seedlings have the same shades of light greenish-yellow color with a little radiance. Inferior Crab seedlings have different shades, and tender seedlings and old seedlings are uneven. (3) Look at the strength of activities. It is advisable for the crab seedlings to drain the water naturally. Do not dry it on the nylon net to avoid injury. Grab a hand, gently pinch, and then put it into the crab seedling box to see its activity. When the palm is grasped, the palm of the hand feels rough, and it is put into the crab seedling box. The crab crawls quickly and can quickly spread to the surrounding area. It is a high quality seedling. The palm of the hand does not have a rough feeling, and it is still a group when it is slowly dispersed in the seedling box. It is a poor quality seedling. (4) If possible, a sampling check is made, which refers to 1 to 2 grams of crab seedlings counted as the number of crabs per kilogram, generally 141-16 thousand high quality larvae per kilogram of macrolarvae, and 16-18 million as medium Seedlings, more than 180,000 were inferior seedlings. Surgical Face Mask Online,Surgical 3D Mask Online,Surgical Face Mask,Non-Woven N95 Face Mask Dongguan City Risen Medical Products Co., Ltd. , https://www.risenppe.com