Are milk and cheese okay for birds?
Birds are not mammals and do not possess the enzyme necessary to break down lactose that is in milk and its diary byproducts, such as cheese. Therefore birds will get some degree of indigestion when being fed dairy products!
Bird embryos are enclosed in an egg during incubation. This means that when the egg is laid, it does contain all the nutrients and fluids necessary to sustain the bird until it hatches. Once it hatches, the parent birds regurgitate foods that they have eaten to feed the chicks, as birds are unable to produce milk. It makes sense then that milk and products containing milk would be totally foreign food items to a bird. Nowhere in its natural environment would a bird ever be exposed to milk, cheese, yogurt or other products containing milk. It should also make sense that birds would not have developed the enzymes necessary to digest milk sugar.
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