Manganese. Adding 20% to 25% of manganese to the chicken feed can make the hen produce hard-shelled eggs without increasing eggshell thickness. The broken rate of this egg is greatly reduced for storage and transportation.
Baking soda. Add about 0.5% of baking soda in the layer of chicken feed, laying eggs significantly increased egg production, eggshell thickness also increased, the utilization of protein in the feed layer increased utilization. This is because the addition of baking soda to the feed can ensure the level of sodium in the chicken's blood, which is beneficial to the formation of eggs.