Important terms in genetics and breeding
Animal biotechnologies are tools used in genetic selection. Scientists and animal breeders use biotechnology to produce healthier animals, make breeding easier and to produce more food for people. Animal breeders can improve the breeding process through techniques like artificial insemination, cloning and genetic engineering.
Artificial insemination (AI) is when animal breeders place semen from a male animal into a female animal. The sperm from the semen meets with the female’s egg and a baby animal begins to develop. Artificial insemination makes it possible for breeders throughout the world to introduce the best traits into their herds, even though males with those traits might not live nearby.
Producers have accomplished a lot by using AI. Although AI is now common place in animal breeding, it was initially viewed with skepticism. Some people feared that AI was unnatural and would lead to problems in baby animals, but later research showed that AI was safe and useful. Seventy percent of all dairy cows in the United States are bred using AI, as are virtually all turkeys and chickens. Artificial insemination has been used to improve environmental sustainability and food production. Over the last 100 years, advances in the genetics, nutrition and management of U.S. dairy cows have resulted in a greater than four-fold increase in milk production per cow and a three-fold improvement in production efficiency. Production efficiency in dairy cows is the amount of milk produce for each pound of feed a cow eats. About half of this increase in production efficiency came from the use of AI to improve genetics.
As a result, a much smaller population of dairy cows is currently providing milk for U.S. consumers. This means dairy cows have less of an impact on the environment because fewer cows need less land, food and water.
Cloning is another form of biotechnology used in animal production. Identical twins are an example of naturally occurring cloning. In recent years, scientists have figured out how to make clones in the lab.
The first mammal to be intentionally cloned from an adult cell was a sheep called Dolly in 1996. Dolly was created using the technique of somatic cell nuclear transfer. In animal cells, the nucleus is the part of the cell that stores genetic material. To make Dolly, scientists transferred the nucleus from one cell into an unfertilized egg that had had its own nucleus removed. That egg was then implanted into the womb of a surrogate mother sheep where it grew into Dolly. The production of Dolly showed for the first time that genes in the nucleus of a mature animal cell can change back into genes for growing a baby animal.
In the United States, the consumption of meat and other products from cloned animals was approved by the Food and Drug Administration (FDA) in 2006, and no special labeling is required. Food from clones is no different to food from non-cloned animals.
Genetic engineering is another useful tool in animal production. Genetic engineering introduces new genes to the food animal population. Animal breeders are interested in using this technology to increase animal productivity, improve resistance to diseases and parasites, and make food more nutritious. Genetically engineered animals are regulated by the FDA under the Food, Drug and Cosmetics Act.
Currently, there are no genetically engineered food animals approved for sale in the United States, but there are some animals awaiting approval. A company called AquaBounty has requested FDA approval to market a growth-enhanced Atlantic salmon that is capable of growing faster (but not larger) than standard salmon. As of June 2012, a decision regarding this request to approve the “AquAdvantage” salmon is still pending.