I am a poultry farmer and I normally face this problem of pecking among my layers. I give them the required quantity of feed and medicate them when the need arises. They normally peck and or lick the eggs after laying.
This happens as a result of stress in any form i.e. Type of breed, Heat, Poor ventilation, Lack of certain ingredients in the feed, orientation of the housing etc. The immediate measure to take is to get some leaves like waterleaf, cabbage, and spinach etc. and run to consult a specialist.
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