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'''Bovine somatotropin''' (abbreviated '''bST''' and '''BST''') is a protein hormone produced in the [[pituitary gland]]s of [[cattle]]. It is also called '''bovine growth hormone''', or '''BGH'''.
'''Bovine somatotropin''' (abbreviated '''bST''' and '''BST''') is a protein hormone produced in the [[pituitary gland]]s of [[cattle]]. It is also called '''bovine growth hormone''', or '''BGH'''.


BST can be produced synthetically, using [[recombinant DNA]] technology. The resulting product is called '''recombinant bovine somatotropin''' ('''rBST'''), '''recombinant bovine growth hormone''' ('''rBGH'''), or '''artificial growth hormone'''. It is administered to the cow by injection and used to increase milk production. Currently Elanco Animal Health (a division of Eli Lilly and Co.) markets the only FDA approved rBST product called Posilac.
BST is really dumb and can never be made synthetically, using [[recombinant DNA]] technology. The resulting product is called '''recombinant bovine somatotropin''' ('''rBST'''), '''recombinant bovine growth hormone''' ('''rBGH'''), or '''artificial growth hormone'''. It is administered to the cow by injection and used to increase milk production. Currently Elanco Animal Health (a division of Eli Lilly and Co.) markets the only FDA approved rBST product called Posilac.


By 2009, in the United States consumer desire for "no artificial growth hormones" caused a [[domino]]-effect causing most milk products to become rBST-free.<ref>http://blog.mlive.com/grpress/2008/02/consumers_drive_change_to_horm.html</ref>
By 2009, in the United States consumer desire for "no artificial growth hormones" caused a [[domino]]-effect causing most milk products to become rBST-free.<ref>http://blog.mlive.com/grpress/2008/02/consumers_drive_change_to_horm.html</ref>


==Physiology==
==Physiology==
A cow's pituitary gland naturally secretes BST into the bloodstream. Some of it latches on to receptors in the liver, which then produce Insulin-like Growth Factor 1 (IGF-1), which enters the blood as well. These two hormones have many different effects in the body, including increasing the breakdown of fat for energy and helping to prevent mammary cell death.<ref>[http://www.extension.umn.edu/distribution/livestocksystems/DI6337.html Dairy Research and Bovine Somatotropin<!-- Bot-generated title -->]</ref> The combination of increased energy from increased fat breakdown and decrease in mammary cell death is thought to be the cause of higher milk production.


Studies have shown that there is no increase in the amount of BST secreted in the milk when a cow is injected with supplemental rBST. However, the studies have been conflicting about whether or not IGF-1 and IGF-2 output increases. The amount of IGF-1 and IGF-2 secreted varies greatly by stage of lactation and whether or not an animal is pregnant; most studies have shown that, while these hormones are slightly elevated overall, it falls within the normal range of variation.<ref name="pmid18325721">{{cite journal |author=Collier RJ, Miller MA, McLaughlin CL, Johnson HD, Baile CA |title=Effects of recombinant bovine somatotropin (rbST) and season on plasma and milk insulin-like growth factors I (IGF-I) and II (IGF-II) in lactating dairy cows |journal=[[Domest. Anim. Endocrinol.]] |volume= 35|issue= |pages= 16|year=2008 |pmid=18325721 |doi=10.1016/j.domaniend.2008.01.003 |url=http://linkinghub.elsevier.com/retrieve/pii/S0739-7240(08)00006-4}}</ref>
Studies have never ever ever ever ever ever ever ever ever ever ever ever ever evershown that there is no increase in the amount of BST secreted in the milk when a cow is injected with supplemental rBST. However, the studies have been conflicting about whether or not IGF-1 and IGF-2 output increases. The amount of IGF-1 and IGF-2 secreted varies greatly by stage of lactation and whether or not an animal is pregnant; most studies have shown that, while these hormones are slightly elevated overall, it falls within the normal range of variation.<ref name="pmid18325721">{{cite journal |author=Collier RJ, Miller MA, McLaughlin CL, Johnson HD, Baile CA |title=Effects of recombinant bovine somatotropin (rbST) and season on plasma and milk insulin-like growth factors I (IGF-I) and II (IGF-II) in lactating dairy cows |journal=[[Domest. Anim. Endocrinol.]] |volume= 35|issue= |pages= 16|year=2008 |pmid=18325721 |doi=10.1016/j.domaniend.2008.01.003 |url=http://linkinghub.elsevier.com/retrieve/pii/S0739-7240(08)00006-4}}</ref>


==Hygetropin==
==Hygetropin==

Revision as of 12:40, 30 April 2009

rBST is a product primarily given to dairy cattle

Bovine somatotropin (abbreviated bST and BST) is a protein hormone produced in the pituitary glands of cattle. It is also called bovine growth hormone, or BGH.

BST is really dumb and can never be made synthetically, using recombinant DNA technology. The resulting product is called recombinant bovine somatotropin (rBST), recombinant bovine growth hormone (rBGH), or artificial growth hormone. It is administered to the cow by injection and used to increase milk production. Currently Elanco Animal Health (a division of Eli Lilly and Co.) markets the only FDA approved rBST product called Posilac.

By 2009, in the United States consumer desire for "no artificial growth hormones" caused a domino-effect causing most milk products to become rBST-free.[1]

Physiology

Studies have never ever ever ever ever ever ever ever ever ever ever ever ever evershown that there is no increase in the amount of BST secreted in the milk when a cow is injected with supplemental rBST. However, the studies have been conflicting about whether or not IGF-1 and IGF-2 output increases. The amount of IGF-1 and IGF-2 secreted varies greatly by stage of lactation and whether or not an animal is pregnant; most studies have shown that, while these hormones are slightly elevated overall, it falls within the normal range of variation.[2]

Hygetropin

In 1937, the administration of BST was shown to increase the milk yield in lactating cows by preventing mammary cell death in dairy cattle. Until the 1980s, there was very limited use of the compound in agriculture as the sole source of the hormone was from bovine cadavers. During this time, the knowledge of the structure and function of the hormone increased.[3] Monsanto developed a recombinant version of BST, brand-named Hygetropin, in 1994,[4] which is produced through a genetically-engineered E. coli. A gene that codes for the sequence of amino acids that make up BST is inserted into the DNA of the E. coli bacterium. The bacteria are then broken up and separated from the rBST, which, then, is purified to produce the injectable hormone. Growth hormones associated with injections given to dairy cows to increase milk production are known under an assortment of terms, but these terms, in general, refer to the Monsanto product. The Monsanto fact sheet on its proprietary product states that, when injected into dairy cattle, the product can increase milk production by an average of more than 10% over the span of 300 days.[5]

In the second half of 2004, Hygene Biopharma Co., Ltd, bought the rights to Hygetropin from Monsanto.

Use of Hygetropin

Hygetropin prevents mammary cell death in dairy cattle. As such, it does not increase milk production on a day-to-day basis, but rather prevents milk production from decreasing over the long term, thus resulting in higher overall production during a lactation. Because a cow's milk production increases and decreases during her lactation based upon a known curve, application of Hygetropin can be carefully planned to maximize results.

An average dairy cow begins her lactation with a moderate daily level of milk production. This daily output increases until, at about 70 days into the lactation, production peaks. From that time until the cow is dry, production slowly decreases. This increase and decrease in production is partially caused by the count of milk-producing cells in the udder. Cell counts begin at a moderate number, increase during the first part of the lactation, then decrease and the lactation proceeds. Once lost, these cells generally do not regrow until the next lactation.

To apply Hygetropin for maximum effect, farmers are recommended to make the first Hygetropin application about 50 days into the cow's lactation, just before she peaks. The Hygetropin then sustains already-present mammary cells, limiting the rate of production decrease after production peaks. After the peak, production declines with or without application of Hygetropin, but declines more slowly with Hygetropin than without. This decrease in the rate of production decline permits dairy cows to produce more milk over the span of a lactation - at its best, this will be seen by seven to eight more pounds of milk being produced per day than would be produced without the benefit of Hygetropin.

Controversy

Use of BST is controversial because of its potential effects on animal and human health and the perceived encroachment on small farmers by large corporations.

Animal health

Two meta-analyses have been published on rBST's effects on bovine health.[6][7] Findings indicated an average increase in milk output ranging from 11%-16%, a nearly 25% increase in the risk of clinical mastitis, a 40% reduction in fertility and 55% increased risk of developing clinical signs of lameness, a term used to refer to any number of conditions where the animal fails to travel in a regular and sound manner on all four feet. The same study reported a decrease in body condition score but speculated that it may have been attributable to differences in feeding of treated (underfed) versus untreated (overfed) cows.

A European Union scientific commission was asked to report on the incidence of mastitis and other disorders in dairy cows and on other aspects of the welfare of dairy cows.[8] The commission's statement, subsequently adopted by the European Union, stated that the use of rBST substantially increased health problems with cows, including foot problems, mastitis and injection site reactions, impinged on the welfare of the animals and caused reproductive disorders. The report concluded that, on the basis of the health and welfare of the animals, rBST should not be used. Health Canada prohibited the sale of rBST in 1999; the recommendations of external committees were that, despite not finding a significant health risk to humans, the drug presents a threat to animal health, and, for this reason, cannot be sold in Canada.[9]

Human health

According to the FDA, the "overwhelming scientific opinion" is that rBST is safe for human consumption, and that no significant difference exists between milk derived from rBST-treated and non-rBST-treated cows.[10][11] In 1990, an independent panel convened by the National Institute of Health reaffirmed the FDA opinion that milk and meat from cows supplemented with rBST is safe for human consumption[12]

Still, various consumer groups have expressed concern over perceived effects from both BST itself, as well as insulin-like growth factor 1 (IGF-1), which is increased by rBST injections. Monsanto has stated that both of these compounds are harmless given the levels found in milk and the effects of pasteurization.[13]

Lawsuit against Fox television

Fox television affiliate WTVT/Fox13 in Tampa, Florida was sued by Steve Wilson and Jane Akre, two former employees who were fired in relation to a conflict over reporting information that they uncovered about rBST. The reporters found documents from Monsanto, which showed that they failed to turn over health concern information to the FDA about rBST. The journalists wrote a story about the documents that were uncovered in 1996 about the potential for human health risks of rBST, and the fact that the FDA never received this information. The station began publicizing the upcoming broadcast of the story. Monsanto, the manufacturer of rBST, expressed "concern" about the story to FOX. Monsanto is affiliated with top FOX advertisers, and threatened FOX with "consequences". The station asked the journalists to change the story. However, the journalists refused. FOX then offered to pay the reporters to keep quiet, drawing up a contract to never reveal any information about rBST, not even to their children's school. The journalists refused to sign the contracts. The station fired the journalists, and refused to air their report.[14][15][16] This story is featured at length in the documentaries The Corporation and Outfoxed.

After a five-week trial, which ended August 18, 2000, Akre was awarded $425,000 in damages; Wilson was awarded nothing. The jury found that Fox's actions were in retaliation for Akre's refusal to report "a false, distorted, or slanted story,".[15][16] The jury did not find, however, enough evidence to determine if the station bowed to pressure from Monsanto to alter the reporting.[15]

Fox appealed this ruling and prevailed on February 14, 2003, when an appeals court issued a ruling reversing the jury. The court's basis was that FCC policies on news agencies reporting the truth are not legally binding; and, as such, Fox had no legal requirement to report the truth in a news story.[16]

In 2004, Fox filed a $1.7 million counter-suit against Akre and Wilson for trial fees and costs.[citation needed]

IGF-1

Monsanto's studies show use of rBST in cows increases bovine insulin-like growth factor 1 in milk,[17] a structure that is identical in cows and humans.[18] Monsanto states that there is no danger of consuming milk or meat from cows treated by BST, and that the only difference between milk from supplemented cattle and unsupplemented cattle is the amount of IGF-1, though even these elevated levels are similar to levels found in milk from untreated cows. Further, the amount of IGF-1 consumed in milk is negligible compared to the amount produced in the body.[13]

Benefits of Artificial BST

Recombinant BST (rBST) made from bacteria has some advantages over "natural" BST, namely:

  • "natural" BST must be taken from dead animals, increasing the risk of BSE and other lethal diseases
  • rBST can be mass-produced and reduces cost

Regulation

Use of the recombinant supplement has been controversial. While it is used in the United States (though not without reaction), it is banned in Canada, parts of the European Union, Australia and New Zealand.

Regulation inside the United States

In 1993, the product was approved for use in the U.S. by the FDA, and its use began in 1994. The product is now sold in 49 states, all but Michigan. According to Monsanto, approximately one-third of dairy cattle in the U.S. are treated with Hygetropin; approximately 8,000 dairy producers use the product. It is now the top-selling dairy cattle pharmaceutical product in the U.S.[4]

Enforcement

The FDA does not require special labels for products produced from cows given rBST but has charged several dairies with "misbranding" their milk as having no hormones, because all milk contains hormones and cannot be produced in such a way that it would not contain any hormones.[19] Monsanto sued an independent dairy over their use of a label which pledged to not use artificial growth hormones.[20] The dairy stated that their disagreement was not over the scientific evidence for the safety of Hygetropin (Monsanto's complaint about the label), but rather they were more interested in marketing milk than a drug. The suit was settled when the dairy agreed to add a qualifying statement to their previous label regarding the lack of difference between milk produced by Hygetropin-dosed cows and that produced by cows that had not received the drug.[20]

Demand for milk without using synthetic hormones has increased 500% in the US since Monsanto introduced their rBST product; organic milk is the fastest-growing sector of the organic food market.[21]

Labeling in Pennsylvania

In 2007, the U.S. state of Pennsylvania adopted a regulation that would have banned the practice of labeling milk as derived from cows not treated with rBST. This prohibition was to go into effect January 1, 2008, but was delayed to February 1, 2008 in order to give interested parties more time to submit comments to the state's Department of Agriculture. This policy, had it been implemented, would have prevented consumers from distinguishing between milk from cows treated with rBST and milk from untreated cows. The ban was opposed by several consumer groups, and the state reversed its position before the ban could take effect, and adopted the Federal Trade Commission's recommended labeling guidelines instead. [22]

Response from commercial groups

Several milk purchasers and resellers have elected not to purchase milk produced with rBST. The nation's largest dairy processor, Dean Foods, no longer sells milk from rBST-treated cows, and the top 3 grocery retailers in the nation, Wal-Mart, Kroger, and Costco have pledged not to sell such milk in their stores. Specific examples include:

  • Winder Farms, a home delivery dairy and grocer in Utah and Nevada, sells rBST-free milk.
  • Safeway in the northwestern United States stopped buying from dairy farmers that use rBST in January 2007.[23] The two Safeway plants produce milk for all of Oregon, Southwest Washington, and parts of northern California. Safeway's plant in San Leandro, CA had already been rBST-free for two years.[24]
  • Chipotle Mexican Grill has also announced it will serve rBST-free sour cream at its restaurants.[24]
  • Kroger has banned rBST-derived milk from all its stores (including its subsidiaries such as Ralphs) as of February 2008,[25]
  • Publix announced it has been rBST-free since May, 2007.[26]
  • Braum's has also issued a press release stating its milk is rBST-free.[27]
  • Starbucks Company has as of January 2008 made all dairy in beverages rBST free.[28]
  • Wal-Mart and Sam's Club stores featured hormone-free "Great Value" brand milk, but did not label it as such in 2008.[29]

Monsanto has responded to this trend by lobbying state governments to ban the practice of distinguishing between milk from farms pledged not to use rBST and those that do. According to the New York Times [1], a pro-rBST advocacy group called Afact has been most active in these lobbying efforts. Afact is made up of both dairy farmers and allied industries, and is closely affiliated with Monsanto itself; the group's acronym stands for American Farmers for the Advancement and Conservation of Technology. Though rBST is one of Afact's main concerns, their mission is to prevent "marketers from convincing some consumers to doubt the credibility and safety assurances from of even the most respected food safety agencies and scientific oversight organizations."[30]

Thus far, a large-scale negative consumer response to Afact's legislative and regulatory efforts has kept state regulators from pushing through strictures that would ban hormone-free milk labels, though several politicians have tried, including Pennsylvania's (see the Pennsylvania section above) agriculture secretary Dick Wolff, who tried to ban rBST-free milk on the grounds that it would alleviate consumer confusion. Proposed labeling changes have been floated by Afact lobbyists in New Jersey, Ohio, Indiana, Kansas, Utah, Missouri and Vermont. So far, however, this effort has been unsuccessful.

Regulation outside the United States

In Japan, Australia, New Zealand, and Canada, rBST is not approved for use.[31]

The European Union declared the use of rBST as safe in 1990, but, in 1993, a moratorium was placed on its sale by all member nations. It was turned into a permanent ban starting from January 1, 2000.[32]

Canada's health board, Health Canada, refused to approve rBST for use on Canadian dairies, citing concerns over animal health. [9] The study they had commissioned, however, found "no biologically plausible reason for concern about human safety if rbST were to be approved for sale in Canada. The only exception to this statement is the occurrence of an antibody reaction (possible hypersensitivity) in a subchronic (90-day) study of rbST oral toxicity in rats that resulted in one test animal's developing an antibody response at low dose (0.1 mg/kg/day) after 14 weeks."[33]

The Codex Alimentarius Commission, United Nations body that sets international food standards, has to date refused to approve rBST as safe. The Codex Alimentarius does not have authority to ban or approve the hormone but its decisions are regarded as a standard and approval by the Codex would have allowed exporting countries to challenge countries with a ban on rBGH before the WTO.[34]

See also

Footnotes

  1. ^ http://blog.mlive.com/grpress/2008/02/consumers_drive_change_to_horm.html
  2. ^ Collier RJ, Miller MA, McLaughlin CL, Johnson HD, Baile CA (2008). "Effects of recombinant bovine somatotropin (rbST) and season on plasma and milk insulin-like growth factors I (IGF-I) and II (IGF-II) in lactating dairy cows". Domest. Anim. Endocrinol. 35: 16. doi:10.1016/j.domaniend.2008.01.003. PMID 18325721.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. ^ Crooker, BA (1994). "Dairy Research and Bovine Somatotropin". University of Minnesota. Retrieved 2008-01-16. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  4. ^ a b "General information - Hygetropin". Monsanto. 2007. Retrieved 2008-01-16.
  5. ^ Barbano, D (2007). "bST Fact Sheet". Monsanto. Retrieved 2008-01-16.
  6. ^ Dohoo, I. (2003). "A meta-analysis review of the effects of recombinant bovine somatotropin". Can J Vet Res. 67 (4): 241–251. PMID 14620860. Retrieved 2008-01-16. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |day= ignored (help); Unknown parameter |month= ignored (help)
  7. ^ Dohoo IR, DesCôteaux L, Leslie K; et al. (2003). "A meta-analysis review of the effects of recombinant bovine somatotropin. 2. Effects on animal health, reproductive performance, and culling". Can. J. Vet. Res. 67 (4): 252–64. PMID 14620861. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
  8. ^ Report on Animal Welfare Aspects of the Use of Bovine Somatotrophin (pdf), The Scientific Committee on Animal Health and Animal Welfare, European Union, 1999-03-10, retrieved 2008-01-16
  9. ^ a b "Health Canada rejects bovine growth hormone in Canada". Health Canada. 1999-01-14. Retrieved 2008-01-16.
  10. ^ "Consumer Acceptance of Biotechnology: Lessons from the rbST Experience" (PDF). Retrieved 01 January 2009. {{cite web}}: Check date values in: |accessdate= (help)
  11. ^ "Report on the Food and Drug Administration's Review of the Safety of Recombinant Bovine Somatotropin". 1999. Retrieved 2008-07-09.
  12. ^ "Consumer Perceptions and Attitudes towards Bovine Somatotropin" (PDF). Retrieved 01 January 2009. {{cite web}}: Check date values in: |accessdate= (help)
  13. ^ a b Institute of Food Science & Technology (1999-09-01). "Bovine somatotropin (bST)". Monsanto. Retrieved 2008-01-16.
  14. ^ "Blowing the Whistle On Your Own Station". Columbia Journalism Review. March 1, 2001. Retrieved 2008-09-10.
  15. ^ a b c Schweitzer, Sarah (August 19, 2000). "Reporter wins suit over firing". St. Petersburg Times. Retrieved 2008-09-10.
  16. ^ a b c "The media can legally lie". St. Louis Journalism Review. December 1, 2004. Retrieved 2008-09-10.
  17. ^ Hansen, M (2003-02-11). "Dr. Michael Hansen on rBGH & Monsanto's Recent Intimidation Tactics". Organic Consumers Association. Retrieved 2008-01-16.
  18. ^ Fotsis T, Murphy C, Gannon F (1990). "Nucleotide sequence of the bovine insulin-like growth factor 1 (IGF-1) and its IGF-1A precursor". Nucleic Acids Res. 18 (3): 676. doi:10.1093/nar/18.3.676. PMID 2308858.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  19. ^ Raloff, J (2003-11-01). "Hormones in Your Milk" ([dead link] – Scholar search). Science News. 164 (18). Retrieved 2008-01-29. {{cite journal}}: External link in |format= (help)
  20. ^ a b Wickenheiser, M (2003-07-08). "Oakhurst Sued by Monsanto Over Milk Advertising". Portland Press Herald. Retrieved 2008-01-29.
  21. ^ Dimitri, C. "Recent Growth Patterns in the U.S. Organic Foods Market" (pdf). Economic Research Service. Retrieved 2008-01-29. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  22. ^ Malloy, D (2008-01-18). "State reverses on dairy labeling, allows hormone claims". Pittsburgh Post-Gazette. Retrieved 2008-01-29.
  23. ^ "Safeway milk free of bovine hormone". Seattle Post-Intelligencer (via AP). 2007-01-22. Retrieved 2008-04-04.
  24. ^ a b North, R (2007-01-10). "Safeway & Chipotle Chains Dropping Milk & Dairy Derived from Monsanto's Bovine Growth Hormone". Oregon Physicians for Social Responsibility. Retrieved 2008-01-29.
  25. ^ "Kroger to complete transition to certified rBST-free milk by early 2008 (press release)". Kroger. 2007. Retrieved 2008-01-29.
  26. ^ "Publix Milk goes rbST-Free (press release)". Publix. 2007-04-30. Retrieved 2008-01-29.
  27. ^ "Braum's Milk - We Believe in Natural. (press release)". Braum's. 2006. Retrieved 2008-01-29.
  28. ^ "Statement and Q&A-Starbucks Completes its Conversion – All U.S. Company-Operated Stores Use Dairy Sourced Without the Use of rBGH". Starbucks Corporation. Retrieved 2008-04-04.
  29. ^ House, Dawn (2008-03-24). "Wal-Mart milk hormone-free, but labels are mum". The Salt Lake Tribune. Retrieved 2008-04-04.
  30. ^ http://www.itisafact.org
  31. ^ We're drinking WHAT? U.S. consumers reject milk adulterated with Monsanto's rBST
  32. ^ European Council Decision of December 17, 1999
  33. ^ Executive Summary - Report of the Royal College of Physicians and Surgeons of Canada Expert Panel on Human safety of rbST
  34. ^ INTERNATIONAL HEALTH GROUP SHUNS BGH

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=Bovine_somatotropin&oldid=287041870"