Ackman bets big on cows, chickens, cats

Jin Lee | Bloomberg | Getty Images

Fresh off a big win from investing in medicine for humans, Bill Ackman is now focused on pharmaceuticals for animals.

Pershing Square Capital management recently disclosed an 8.5 percent stake in Zoetis, which makes animal medicine and vaccines that are bought by veterinarians, livestock farmers and other animal owners.

Ackman praised Zoetis in a Nov. 25 letter to Pershing Square clients. "Zoetis' business model passes Pershing Square's high bar for business quality," he wrote.

The letter also said that Zoetis' product portfolio is "highly durable" and that competition from rival generic-drug makers was "minimal." Animal health products, Ackman noted, are produced at a relatively low volume with smaller profit margins, benefiting established brands like Zoetis.