A rare white buffalo calf born in Texas and believed to have been skinned and mutilated actually died from a bacterial infection, authorities say.

The buffalo belonged to the Little Soldier family–a Native American tribe–and was revered by locals because of lore related to the goddess of peace appearing as a white buffalo. The calf, named Lightning Medicine Cloud, was found dead in May; her mother, Buffalo Woman, was found dead the next day. There have been two more deaths on the ranch since then, and investigators believe they’re due to a bacterial infection caused by something called blackleg, whose spores lay dormant on the land and are eventually either eaten by livestock or are introduced to their systems through wounds. Although there is a vaccine for blackleg, it is generally used for cattle and isn’t known to be effective in buffalo.

“Normally they’re healthy one day and the rancher finds them dead the next,” Terry Hensley, a Texas veterinarian, said.

Arby Little Soldier, owner of the ranch, says he believes the calf and her mother were poisoned and is offering a $45,000 reward for information.