Genetic engineering and cloning may improve milk, livestock production

In the past, procedures such as artificial insemination and embryo transfer have been used in the genetic manipulation of livestock. Advances in gene and quantitative-trait mapping will enhance these traditional animal-breeding approaches to improve farm animals. By genetically engineering livestock, scientists hope to produce animals with altered traits such as disease resistance, wool growth, body growth and milk composition. Laboratories world wide have produced transgenic pigs, sheep, goats and cattle, but currently the efficiency of producing the animals remains low and the procedure is expensive. Within the next few decades, however, genetically engineered dairy cows could become available. Cloning may also be used to duplicate animals with traits that are difficult to capture through traditional breeding practices. By 2025, cloning and breeding of elite animals could be carried out by companies comparable to those that now comprise the artificial insemination industry, which selects and breeds top dairy stock. The acceptance of genetically engineered animals by industry will depend on its economic benefits and whether consumers are prepared to buy the resulting products.