Benjamin and Nicholas Conley are charged with animal killing — a 4-year felony.
At least five cats have been beaten, tortured or killed since March in a small, West Michigan village.
A small dog found skinned and stabbed is now in the care of veterinarians in Ann Arbor.
The plan requires the use of lethal injections when unwanted dogs and cats are killed.
The Labrador retriever-mix was found just before 10 p.m. in the Rouge River with a brick tied to his leg.
Dearborn Heights Police say someone tied a brick to the leg of a dog and dumped it in the Rouge River this week.
Police called to a barn in Macomb County found the remains of several dead animals and removed 19 other malnourished animals from the property.
Authorities removed dozens of animals from a West Michigan home where they found at least 10 dead kittens and a fawn in a freezer.
Michigan Humane Society cruelty investigators say no humans were involved in the killing of more than a dozen animals at an urban farm operated by students at a Detroit alternative high school.
The school’s principal said it looked as if “some crazy person had gone crazy on the animals.”