Complex sentence: An animal control officer in the United States may be an employee of or a contractor to a municipality and is charged with responding to requests for help with wild animals, dangerous animals or animals in distress.
Split into simpler sentences: An animal control officer in the United States may be an employee of or a contractor to a municipality and is charged with responding to calls for service from the general public. Calls may include requests for help with wild animals, dangerous animals or animals in distress.