Breast neoplasia is considered the second most common neoplasm. Affects domestic animals, with the main diagnosis being in female dog, which can affect females aged between approximately 7 and 12 years, however it can also be seen in young animals, and then even related to the sexual and hormonal integrity of the bitch. Breast tumors can manifest in different ways and stages, which varies according to the type of tumor (neoplastic or not), affected cell and degree of aggressiveness, where generally 68.4% of breast tumors diagnosed in dogs are malignant. The aim of this work is to review the effects of ovariohysterectomy performed in domestic females in what is said respect to the development of breast neoplasms, aiming to bridge the processes pathophysiological 1 involved, such as particularities of the estrous cycle in bitches, administration of contraceptives, environmental and endogenous factors of the animal itself, corresponding age and predisposed breeds, clarifying the importance of procedure for both the prevention of breast cancer in bitches, as well as other illnesses.