What caused the most severe population losses for the Berger Picard in the mid-20th century?

Answer

World War II

World War II is explicitly mentioned as having more severely impacted the already small population of Picards than World War I, leading to catastrophic losses.

What caused the most severe population losses for the Berger Picard in the mid-20th century?
raceOriginDogbreedingBerger Picard