Milk Money?

How can dairy farmers increase milk production without increasing the size of their herds? With genetic engineering. A genetically engineered hormone called rBGH (recombinant Bovine Growth Hormone) can increase a cow's milk production by 10-15%. RBGH is a genetically engineered copy of a hormone that occurs naturally in cows. The genetically engineered hormone must be injected into the cow daily to boost production.

How Does It Work?

The hormone is mass-produced by bacteria. The gene that controls production of the hormone is engineered into the bacteria's genetic code, turning the bacteria into a mini-hormone factory. The FDA approved the use of rBGH back in 1993, and an estimated 10% of the nation's dairy herd is injected with rBGH.

Why Shouldn't We Use It?

Critics of the hormone say that there is a downside to increased milk production. The hormone increases the "wear and tear" on the cow, and can have serious physical side effects on the animals. (Cow udders may develop painful sores and ulcers.) In addition, critics say there's already too much milk produced in the U.S. , and rBGH is simply boosting the bottom line for the companies that produce it.


Explore More: Genetic Engineering
Copyright 2004, Iowa Public Television
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