Long-acting veterinary polypeptides and methods of producing and administering same

A method of producing a non-human growth hormone with an improved biological half life in an isolated cell, comprising the step of transfecting said cell with an expression vector comprising a polynucleotide consisting of a nucleic acid encoding a polypeptide, said polypeptide consisting of a non-human growth hormone, one chorionic gonadotrophin carboxy terminal peptide (CTP) attached to the amino terminus of said non-human growth hormone, and two chorionic gonadotrophin CTPs attached to the carboxy terminus of said non-human growth hormone, wherein said polypeptide optionally comprises a signal peptide attached to the amino terminus of said one CTP, and wherein at least one CTP is optionally attached to said non-human growth hormone via a linker, thereby producing a non-human growth hormone with an improved biological half life in an isolated cell.