History of Scientific Agriculture: Animals

Abstract

Abstract Domestication of agricultural animals began 10 000 years ago. From a wide array of wild animals, only a small number were and, for specifiable reasons, could be domesticated. Trait selection and breeding has been the principal mechanism of animal improvement until the late twentieth century. As with much of early science, enhancing beneficial traits was a trial and error process. An understanding of the genetic mechanisms and environmental factors in that process was a twentieth‐century triumph. Drawing on physiological, behavioural, genetic, evolutionary and ecological knowledge significantly enhanced selection and breeding efforts. In the twentieth century, scientific advancements were numerous. Of special significance were the introduction of artificial insemination, and the nature, prevention and treatment of pathogenic diseases. Late twentieth‐century agricultural biology began to employ techniques of molecular genetic manipulation (transgenic animals), initially using farm animals as bioreactors. Improvements in cloning, pronuclear injection and use of stem cells can be expected to dominate research and development in twenty‐first‐century animal agriculture. Key Concepts The early evolution of animal domestication was trial and error. Human and agricultural animals coevolved. The mechanisms of speciation were important processes in the early period but only well understood in the twentieth century. The quantitative genetics of farm animal makes trait improvement challenging. Critical variables in the trait farm animals are understood but difficult to manipulate. The importance of multiple trait selection is now well understood. Artificial insemination and cryopreservation of sperm have significantly improved trait manipulation and preservation. Knowledge of pathogens has allowed antibiotics and sanitation to be effectively employed. Animals as pharmaceutical and material bioreactors has been recent and expanded the genetic modification of animals. There are challenges and promises of cloning, pronuclear injection and stem cell use in animal agriculture emerging in the twenty‐first century.