Beattie and his team finished the race on Thursday. The organization says that while carrying out post-race checkups, Iditarod Trail Committee veterinarians examining Oshi noticed signs of pneumonia.
The dog was transported by emergency charter flight to Anchorage on Friday. The dog died the next day.
The Iditarod says a necropsy will be conducted by a board-certified veterinary pathologist to determine the official cause of death.
The 2019 race came during a bruising two-year stretch for the Iditarod that included a dog doping scandal and the loss of national sponsors amid protests by animal rights activists.
On Sunday, a leader of People for the Ethical Treatment of Animals denounced the Iditarod. Tracy Reiman said the race is responsible for the death of Oshi.
“PETA is demanding a full veterinary evaluation of every single dog who was used in the 2019 Iditarod,” Reiman said in a statement, “including the 232 who were pulled from the race, so that the public can see how mushers’ pursuit of the prize purse under the pretense of loving these dogs shows a complete lack of concern in pushing them to and beyond their limits. If this had happened to human athletes, people would be in jail.”
The 1,000-mile race started on March 2 in Anchorage with 52 mushers. Peter Kaiser won with a time of nine days, 23 hours and 39 minutes. The final results showed that 13 mushers, including Beattie, had dropped out.