A complete look at the egg-shaped egg shows that the duck has enough food and feeds, and the feeding and management are better. If the big end of the egg is small, it will be early food; if the small end is sharp, it will ow in the food. Second, look at the eggshell shell thin, trachoma or very rough, soft shell, indicating calcium deficiency, to timely supplement calcium powder, bone meal, shell powder and other mineral feed, to ensure complete nutrition. Three see the egg heavy water, material is sufficient, egg-shaped and full, generally 14 eggs weighs about 1 kilogram; material, water shortage, it takes 16-18 only 1 kilogram. In production, duck feeding and management should be appropriately adjusted according to the weight of eggs. After watching the ducks lay eggs for a period of time, the weight of the ducks still maintains the original level, indicating that the materials used are reasonable; if the weight is reduced, it indicates that the ducks are undernourished. Objective To study the application of spiral fixation for central venous catheter in clinical nursing. Central Venous Catheter(CVC) Cvc Catheter,Medical Cvc Catheter,Single Lumen Central Venous Catheter,Triple Lumen Central Venous Catheter Zhejiang Hisern Medical Device Co., Ltd , https://www.hisernmedical.com