The Humane Society of the United States has increased its reward in the case from $2,500 to $5,000 in the killings, the Houston Chronicle reported.
Since the start of July, 21 of Wayne and Karen Daggs' Barbado sheep have been found dead. The most recent killing happened in early October.
"The mutilation and torture of so many defenseless sheep is a real life horror story and a shocking act of violence within this community," said Katie Jarl, the HSUS state director in a press release. "We are hopeful that this reward will bring forward anyone with information about this heinous crime."