According to provisions of the standard feed, the content of layer feed per kilogram of zinc 40-80mg, shall not exceed 150mg.
Laying hens at low zinc condition is generally not the disease, but hatched chicks will be placed in a low environmental performance of zinc deficiency symptoms. Some scholars have observed deficiency hen soft-shell eggs or egg hatchability. Lucheng Wu et al (1996) reported that zinc deficiency breeder plumage, brittle texture, joint swelling, egg hatching rate. Kienholz et al. (1961) observed that zinc deficiency hen egg production decreased hatchability is extremely low, even hatched chicks also presents a series of zinc deficiency symptoms.
A water content of zinc in zinc sulfate is 34.5%, which added in the form of zinc sulfate monohydrate to broiler feed, zinc sulfate monohydrate added in an amount 115-985mg, for a specific amount of the full price of feed formulation based on zinc the content to be.

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