Why the Confusion?
Some of the confusion and misunderstanding may stem from the fact that the poultry and beef cattle industries operate under different regulations. While growth hormone use is banned in poultry production, it is a perfectly legal and accepted practice in the beef cattle industry.
The Food and Drug Administration (FDA) first approved growth hormones to increase growth, feed efficiency and carcass leanness of beef cattle in 1956. Currently, there are five hormones (progesterone, testosterone, oestrogen, zeranol and trenbolone acetate) approved as growth implants for cattle (Archibeque et al., 2007). Trenbolone acetate and zeranol are synthetic hormones, and the USDA Food Safety Inspection Service routinely monitors for residues of these products to ensure the safety of the beef supply.
Progesterone, testosterone and oestrogen are naturally occurring hormones in both humans and animals. These hormones are necessary for normal development, growth and reproduction. Additionally, humans may ingest steroid hormones as part of hormone replacement therapy and in birth control pills. Of these hormones, oestrogen currently tends to receive the most attention. Oestrogen occurs naturally in both males and females and plays a role in sexual development, reproduction and behaviour (Swyers, 2011). Federal regulatory monitoring of oestrogen, progesterone and testosterone is not possible because it is not possible to tell the difference between hormones used for treatment and those produced naturally by the body.
Unlike poultry (which receive no added growth hormones), most beef cattle fed in the United States do receive a growth-promoting hormone implant, usually when they enter a feedlot. These implants generally are given to beef cattle in the form of a pellet that is surgically implanted under the skin on the back of the animal’s ear. (The ear is used because ears do not enter the food supply.) Over the course of a 100- to 120-day period, the implant slowly dissolves and releases the hormone.
These implants are important in the beef cattle industry because animals spend 100 to 200 days in the feedlot. Recognised benefits of the implants include decreasing the number of days on feed, improving carcass yields, increasing efficiency of the cattle feeding process and keeping beef prices low for the consuming public. However, growth implants can only be used in beef cattle. There are no steroid hormones approved for growth purposes in poultry, dairy cattle, veal calves or pigs.
Some of the confusion and misunderstanding may stem from the fact that the poultry and beef cattle industries operate under different regulations. While growth hormone use is banned in poultry production, it is a perfectly legal and accepted practice in the beef cattle industry.
The Food and Drug Administration (FDA) first approved growth hormones to increase growth, feed efficiency and carcass leanness of beef cattle in 1956. Currently, there are five hormones (progesterone, testosterone, oestrogen, zeranol and trenbolone acetate) approved as growth implants for cattle (Archibeque et al., 2007). Trenbolone acetate and zeranol are synthetic hormones, and the USDA Food Safety Inspection Service routinely monitors for residues of these products to ensure the safety of the beef supply.
Progesterone, testosterone and oestrogen are naturally occurring hormones in both humans and animals. These hormones are necessary for normal development, growth and reproduction. Additionally, humans may ingest steroid hormones as part of hormone replacement therapy and in birth control pills. Of these hormones, oestrogen currently tends to receive the most attention. Oestrogen occurs naturally in both males and females and plays a role in sexual development, reproduction and behaviour (Swyers, 2011). Federal regulatory monitoring of oestrogen, progesterone and testosterone is not possible because it is not possible to tell the difference between hormones used for treatment and those produced naturally by the body.
Unlike poultry (which receive no added growth hormones), most beef cattle fed in the United States do receive a growth-promoting hormone implant, usually when they enter a feedlot. These implants generally are given to beef cattle in the form of a pellet that is surgically implanted under the skin on the back of the animal’s ear. (The ear is used because ears do not enter the food supply.) Over the course of a 100- to 120-day period, the implant slowly dissolves and releases the hormone.
These implants are important in the beef cattle industry because animals spend 100 to 200 days in the feedlot. Recognised benefits of the implants include decreasing the number of days on feed, improving carcass yields, increasing efficiency of the cattle feeding process and keeping beef prices low for the consuming public. However, growth implants can only be used in beef cattle. There are no steroid hormones approved for growth purposes in poultry, dairy cattle, veal calves or pigs.
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