please give a 200 word answer

13.4 Delegation of Duties C.W. Milford owned a registered quarter horse named Hired Chico. Milford sold the horse to Norman Stewart. Recognizing that Hired Chico was a good stud, Milford included the following provision in the written contract that was signed by both parties: I, C.W. Milford, reserve 2 breedings each year on Hired Chico registration #403692 for the life of this stud horse regardless of whom the horse may be sold to. The agreement was filed with the County Court Clerk of Shelby County, Texas. Stewart later sold Hired Chico to Sam McKinnie. Prior to purchasing the horse, McKinnie read the Milford-Stewart contract and testified that he understood the terms of the contract. When McKinnie refused to grant Milford the stud services of Hired Chico, Milford sued McKinnie for breach of contract. Who wins? McKinnie v. Milford, 597 S.W.2d 953, Web 1980 Tex.App. Lexis 3345 (Court of Appeals of Texas)