Bovine somatotropin

filed under | medical | science | food

Share/Bookmark

Bovine somatotropin (abbreviated bST and BST), or BGH, is a chain of amino acids produced by the cow's pituitary gland. Like other hormones, it is produced in small quantities and is used in regulating metabolic processes. Since 1994 it has been possible to synthesize the hormone using recombinant DNA technology to create recombinant bovine somatotropin (rBST), recombinant bovine growth hormone (rBGH), or artificial growth hormone. Monsanto was the first to develop the technology and marketed it as "Posilac" - a brand now owned by Elanco Animal Health, a division of Eli Lilly and Company. A 2007 USDA Dairy Survey estimated rBGH use at 15.2% of operations and 17.2% of cows. 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 as the lactation proceeds. Once lost, these cells generally do not regrow until the next lactation. To apply Posilac for maximum effect, farmers are recommended to make the first Posilac application about 50 days into the cow's lactation, just before she peaks. The Posilac 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 Posilac, but declines more slowly with Posilac 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 Posilac. The United States is the only developed nation to permit humans to drink milk from cows given artificial growth hormone. In Japan, Australia, New Zealand, and Canada, rBST is not approved for use. In 1990, The European Union placed a moratorium on its sale by all member nations. It was turned into a permanent ban starting from January 1, 2000. Canada's health board, Health Canada, refused to approve rBST for use on Canadian dairies, citing concerns over animal health. The Codex Alimentarius Commission, a United Nations body that sets international food standards, has to date refused to approve rBST as safe. In the United States, public opinion has caused a number of products and retailers to become rBST-free. [READ THE REST OF THIS ARTICLE]







wikisnap.com is not affiliated with or endorsed by wikipedia. wikipedia and the wikipedia globe are registered trademarks of wikipedia.org.
article content reproduced in compliance with wikipedia's copyright policy and gnu free documentation license
view our privacy policy and terms of service here