Provided are various embodiments relating to anti-IL31 antibodies having enhanced binding to canine IL31 and feline IL31. Such antibodies can be used in methods to treat IL31-induced conditions in companion animals, such as canines and felines. Antibodies with enhanced binding to canine IL31 and feline IL31 are provided Antibody heavy chains and light chains that are capable of forming antibodies that bind canine and feline IL31 are also provided.