ABSTRACT

This chapter discusses the factors that influence the rate at which a population can be genetically improved, and identifies bull selection and progeny testing as the major source of progress. Data are presented to demonstrate that the New Zealand dairy cattle can match the genetic merit of other populations around the world. The chapter discusses the potential use of induced multiple ovulations and embryo transfer to increase the rate of genetic improvement in dairy cattle. The New Zealand Dairy Board, a farmer cooperative, acts not only to provide dairy farmers with essential services but also acts as marketing cooperative for all dairy products. The method of sire evaluation used in New Zealand has been developing over a long period of time. Several studies have concluded that embryo transfer would contribute little to the rate of genetic improvement in dairy cattle in traditional progeny testing schemes.