Ducks often eat mollusks such as fresh fish and small snails. These animals contain a substance called thiamine that can destroy vitamin B1, so ducks are prone to vitamin B1 deficiency. The disease occurs mostly in young ducklings and often occurs within 2 weeks of age. Therefore, in the case of ducks able to eat aquatic animals, it is necessary to increase the vitamin B1 content in the diet, especially in ducklings. Laying ducks often experience vitamin D deficiency, which is caused by insufficient supply of vitamin D in the diet or insufficient exposure of the birds to sunlight. Diseased waterfowl showed poor growth and development, feathers were unkempt and dull, egg production decreased, shells and soft shell eggs were produced, and eggshells were easily broken. Therefore, it is often necessary to additionally add cod liver oil or vitamin A, D3, E, etc. to the duck feed. Ducks generally lay eggs in the early morning. Therefore, ducks must maintain a high blood calcium concentration in the early morning, otherwise they will produce sand shell eggs, misshapen eggs, and even cause decreased egg production. When preparing egg-laying duck feeds, it is necessary to have a fast-absorbing calcium source and a slowly-absorbing calcium source. Stone powder and shell powder are usually used as calcium sources at the same time. Wearable Breast Pump,Breast Pump,Latex Free Breast Pump,Deep Expression Breast Pump NINGBO YOUHE MOTHER&BABY PRODUCTS CO.,LTD , https://www.oembreastpump.com