What historical factor primarily contributed to the modern Italian Greyhound's fragile gene pool and susceptibility to breakage?

Answer

Deliberate sheltering and later 19th-century breeding focused on making them even smaller

The history of being pampered pets, combined with later 19th-century breeding efforts specifically aimed at achieving smaller size, led to a fragile gene pool and a known propensity for fractures.

What historical factor primarily contributed to the modern Italian Greyhound's fragile gene pool and susceptibility to breakage?
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