To increase the reproductive potential of a genetically superior cow, Tufts Ambulatory Service offers embryo transfer services. Cows are super-ovulated and inseminated, then embryos are collected non-surgically. Embryos can be transferred to recipient cows or frozen to be transferred at a later date. This process greatly increases the number of offspring that one cow can produce, and so is useful to help reproduce genetically superior offspring. Cows that are genetically inferior can serve as surrogate mothers and still contribute to the improvement of the herd.