Dale Parker

Professor Marx

English 134

22 November 2004

There is Nothing Wrong with Bst

As the sun lit the blue sky, my petite hand was engulfed by a long, coarse cow tongue: the Holstein cow enjoyed its morning meal of carrots and celery. The next thing I knew, my alarm clock beeped loudly. My childhood memories of the “petting farm” were interrupted by the reminder of another hike with my English class. This time we were going to the Dairy Unit. After meeting Professor Marx at the classroom, we headed down Mt. Bishop Road, a dirt pathway on the north side of campus. When we reached the barns we were greeted by Leanne Berning, a dairy science professor at Cal Poly. She acted as our tour guide, showing us the baby calves and milking cows. Professor Berning also provided us with insight about the technology Cal Poly uses to produce a sufficient amount of milk.

The black and white Holstein and light brown Jersey calves were the first stop on our tour. Rows of little hutches, each of which provided shelter to one calf, were lined up, forming a square on the dirt ground. Professor Berning explained that these separated hutches are necessary to monitor the development of each calf, as well as their nutritional intake. The dairy workers personally hand-feed each calf colostrum, nutrient rich, premilk fluid secreted from the mammary glands of cows, that helps the calves grow into healthy milking cows. After learning about the calves’ daily diet, we were able to pet their sheer hair and damp pink noses. I liked the Jersey calves better; they were gentle and looked like young deer, brown with white speckles. In contrast, the Holstein calves looked like the “normal” cows I had seen in my childhood; they attracted flies and ate the grain-based feed in front of them.

After leaving the calves, we approached a long walkway of dairy cows. The smell of cow manure filled the air, making my stomach churn. In the corridor, Professor Berning explained that each cow requires an intake of approximately fifty thousand calories a day, eighty percent of which is solely for the production of milk. During the cow’s ten month lactation period, they produce between eighty-six and one hundred and thirty pounds of milk per day. The Cal Poly Dairy uses advanced technology, like rBst and artificial insemination, to increase the efficiency of milk production. I found these technological methods to enhance milk production disturbing: I was concerned about the danger of this milk for the human population and for the cows, whose dangerously full udders look poised to explode.

Back at my dorm, I immediately searched “Google” and found that Bst was an extremely controversial issue in the Dairy Industry. Many dairy consumers appear to have similar concerns about the health effects of Bst (www.nal.usda.gov/bic/BST/US_DAIRY_INDUST_AT_A_Crossroad_PartI_OF_5.htm). However, the majority of web sites that I found were written in scientific terminology beyond my comprehension level.

One week later, I found myself sitting across from Professor Berning in her office asking about Bst and its effects on human population. I wanted to know why it is controversial. She told me that Bst is a natural hormone made by the pituitary gland in cows. Unlike most hormones, Bovine Growth Hormone, another name for Bst, is not a steroid hormone. Instead, it is protein based. Because of the protein makeup of the hormone, the cow is able to clear Bst from the body two minutes after it is released from the pituitary gland. In these two minutes the hormone successfully enables important nutrients in the body to circulate, allowing the cow to grow. Once a cow is fully grown, Bst becomes an important factor in lactation, the period of time that the cow produces milk: Bst affects the mammary gland, causing the cow to produce milk.

Professor Berning explained that Bst produced in the pituitary gland does not cause controversy; controversy lies in the technology developed to produce supplementary rBst. Professor Berning explained that in the early days of milk production the only way to receive additional Bst was through the pituitary glands of deceased cows. This method was not only costly, but a difficult task to complete. However, recent technology has been developed to produce Bst using recombinant DNA technology. Through recombinant DNA technology, scientists are able to extract cow DNA that contains the Bst hormone. They then insert this DNA sample into a microorganism. The microorganism acts as a protein manufacturing plant for the Bst hormone, reproducing the original structure of the hormone. Scientists then harvest the hormone, separate it from the microorganism and insert the additional Bst into the cow. On average a cow that is injected with additional rBst has an increased milk production of ten to fifteen percent.

Berning stated that rBst is necessary to accommodate increased population. Every day farmland is sold for real estate, decreasing the amount of irrigable land in the United States. The lack of farm space has caused the number of cows in the US to greatly diminish. However, consumers still expect to drink milk and eat dairy products daily. Therefore, added rBst is necessary to supply an adequate milk supply.

I later discovered on “google” that because rBst implementation requires expensive technology, many small farm owners oppose Berning’s position. For example, Stephan A. Baker, Ph D., a small farm advocate, stated that “milk output per cow has been increasing (particularly on large farms” primarily as a result of rBst use. This surplus milk production has significantly hurt the small farm industry. Because of the increased production levels of milk and other dairy products, large farms are able to afford the costs of new technology, such as rBst. However, small farms, which make less profit, are crippled by the huge costs connected to rBst.

(www.buckeyeinstitute.org/perspect/1999_6.htm)

Human health poses another controversy for the use of rBst. Even though studies thus far have shown that rBst does not harm humans, many people claim that rBst may in fact cause cancer. Anti-rBst advocates argue that the added Bst increases the level of IGF-1 in the blood. IGF-1 is a leading risk factor for breast cancer; therefore, rBst opponents view rBst as a negative part of the dairy industry. Other studies involving female primates have shown that IGF-1 causes “breast enlargement and proliferation of breast tissue” (http://www.preventcancer.com/press/releases/July8_98.htm).

According to Professor Berning, technology based rBst production does not actually threaten human health. Numerous experiments have shown that the increased Bst in cows does not produce any foreign substances in drinking milk. These studies have also shown that the amount of Bst in milk produced from cows with the DNA injection is equivalent to the amount of Bst in milk without additional Bst. Also, humans consume milk by mouth instead of by injection; therefore, Bst does not go into the blood stream. The protein based hormone can not survive the intense process of the human digestive system. Bst is broken into amino acids, just as if it were any other protein; therefore, the extra Bst in cows is not an issue for humans.

Unlike humans, cows injected with additional Bst are subject to health problems if they are not properly cared for. Berning told me that the increase in milk production as a result of rBst can cause mammary infections in cows. These infections can be prevented if the cow receives sufficient food and water. However, the dairy industry has no official way to regulate the correct nutritional intake of cows; therefore, it is possible that rBst is irresponsibly used, causing harm to the cows.

Although there are no proven health risks involving the use of rBst, many people are fearful about the use of technology. Professor Berning stated that many people feel threatened by the use of technology in general because they do not understand how rBst works. As she put it, “People have a gut reaction: NO” to the hormone without bothering to research the issue. She added that Samuel Epstein, an anti-rBst advocate, raised a huge scare through his published articles in early 1990. Because people did not know the true facts behind rBst, they believed his faulty statements. She concluded by saying that “People need to base their opinion on knowledge” rather than on what they hear. If individuals would look at scientific documents, they would find that rBst does not pose any threat to the human population.

After I finished my interview with Professor Berning and researched rBst, I realized that I no longer questioned use of recombinant DNA for the production of Bst. Prior to educating myself on the issue, I did not understand the degree of controversy that rBst poses. However, after gaining knowledge, I support the use of additional Bst to increase milk production. I think that rBst is a safe way to satisfy the dairy needs of the growing population. I challenge people to research controversial issues before taking a side.

Works Cited

Author Unknown. “Milk: America’s Health Problems.”

http://www.preventcancer.com/press/releases/July8_98.htm.

Author Unknown. “Posilac: Bovine Somotropin by Monsanto.”

http://www.monsantodairy.com

Author Unknown. “US Dairy Industry at a Crossroad: Biotech And Pol…Part I of V.”

www.nal.usda.gov/bic/BST/nad/US_DAIRY_INDUST_AT_A_Crossroad_Part_1_OF_5.htm.

Baker, Stephen A. Ph.D. “Milk Cows, not Consumers.”

http://www.buckeyinstitute.org/perspect/1999_6.htm.

Interview with Leanne Berning. 19 November 2004.