(Photo illustration by Cheng Xin/Getty Images)Getty ImagesZoetis (ZTS) the world’s largest animal-health company, develops and manufactures medicines, vaccines, and diagnostics for both pets and livestock. The stock has come under pressure in recent months as softer clinic traffic, uneven companion-animal demand, and a narrowed full-year outlook weighed on sentiment. Yet the pullback has also driven valuations toward multi-year lows—an unusual reset for a business known for high margins, steady cash generat ...