ABSTRACT
Natural bovine growth hormone (BGH) is a protein hormone that controls bovine growth and lactation. Synthetic bovine growth hormones (rBGH) are manufactured by recombinant DNA biotechnology by the Agriculture Chemicals Division of Eli Lilly and Company in conjunction with the Dow Chemical Company, the Upjohn Company, American Cyanamid, and Monsanto. The increased incidence of infectious disease in cows hyperstimulated by daily injections of rBGH, apart from other toxic effects such as heat intolerance, is highly suggestive of stress reactions. There are significant chemical and molecular differences between rBGH and natural BGH. rBGH contains up to eight additional amino acid groups at one end of the molecule; the FDA has admitted that there are some 3 percent structural differences between these hormones. rBGH administration is likely to reduce normal production of BGH, so that most BGH in milk of treated cows is likely to be rBGH rather than natural BGH.
