What variable, introduced by the diet of urban detritus, is eliminated when consuming birds fed formulated feed like squab?

Answer

Uncontrolled variables in nutritional intake and potential accumulation of environmental contaminants

A major disparity between consuming a wild bird and consuming squab lies in the predictability of what the animal has ingested. Wild pigeons forage among urban detritus, consuming discarded food scraps and other uncontrolled sources, introducing numerous variables regarding potential internal contaminants. Birds raised for squab consumption are fed formulated feed in controlled environments. This managed diet eliminates the uncertainty associated with the wild bird's foraging history, thereby reducing the inherent microbiological load derived from its ingestion sources.

What variable, introduced by the diet of urban detritus, is eliminated when consuming birds fed formulated feed like squab?
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