From this story on cbssports.com:
"...On Wednesday came another report of a hunting accident. Padres right-hander Andrew Cashner had surgery to repair a lacerated tendon in his right thumb after a friend stabbed him in the thumb after he "slipped" while dressing meat, general manager Josh Byrnes told reporters. Earlier on Wednesday, manager Bud Black said the 26-year-old right-hander had been involved in a "minor" hunting accident but didn't have many details. Byrnes filled in the blanks, noting the recovery for Cashner would be three months. He's likely to start the season on the disabled list.