Our house has continually rising levels of Estrogen. I like to tease my husband that he “always wanted to be surrounded by women, and now he is”. As the only male in a house of four women (four opinionated women…), he does at times feel a little bit overwhelmed…We have three male (neutered) cats, and two male (gelded) horses but that falls significantly short of balancing the circulating estrogen (and resulting drama) produced by the two legged girls in his house!
All jokes aside, I would like to take a couple of posts to try and demystify the topic of growth hormone use in my beef cattle. What are they? How do I use them? At what level do I use them? Why do I feel confident that using them is a good decision?
As a college graduate with a major in physiological psychology, I have a basic understanding of the role that hormones play in the lives of both humans and animals.
As a cattle caregiver, I have a vested interest in understanding the role that growth promoting hormones play in the welfare of my cattle and the efficient use of natural resources to produce beef.
As a mother of three developing girls, I have a vested interest in understanding how the use of hormones in beef cattle affects the beef that I feed to my children every day.
- What are they? Hormone implants are small doses of hormones that act on the pituitary gland (in cattle) and cause it to produce more somatotropin which is the animal’s own natural growth promoting agent. This allows the calf to gain more weight with an improved dry matter feed conversion (which means that it takes fewer pounds of feed to create more pounds of beef).
- How do I use them? Calf #718 received a “calf” implant at branding time (the same time that he was castrated). He then received another low dose implant when he arrived at the feed yard eight months later. He received his final implant approximately 80 days prior to harvest. These hormone “implants” are administered according to FDA (Food and Drug Administration) and Beef Quality Assurance guidelines, and are placed in the calf’s ear.
I work with both my nutritionist and veterinarians (you “met” them all in the last couple of weeks), to select appropriate hormone implants and the timing in which they are administered.
- At what level do I use them? The first implant that Calf #718 received immediately following castration contained 10mg (milligrams) of Estradiol and 100mg of Progesterone. The hormone implant given to Calf #718 eight months later, upon arrival at the feed yard, was 36mg of zeranol. The final hormone implant that the calf received contained 24mg of Estradiol and 120mg of Trenbolone Acetate approximately 80 days prior to harvest.
He received these implants in order to replace some of the circulating hormones that were lost due to castration. You might ask, “Why did you castrate the animal and then give him a hormone implant? Why didn’t you just leave the animal “sexually intact” and use the hormones that his body produced?”
The short answer is that I can do a better job managing the hormone levels and their effect on both the animal and his meat by castrating the animal at a young age, and then putting a portion of the hormones lost due to castration back into the animal at timely intervals.
A more moderate level of circulating hormone (which occurs with the correctly timed and administered hormone implant) allows the animal to gain weight efficiently (using fewer natural resources), and produce what I believe is a more tender beef product. It also makes the animal less aggressive than his “intact” herd mate which is a “handling safety” benefit.
Perhaps the most important question of all is: Why do I feel confident that using them is the right thing to do? Click here to see a follow up post answering this questions in addition to providing you will some statistics about the different levels of hormones in beef and other foods that we eat. https://feedyardfoodie.wordpress.com/2011/08/30/unfamiliarity-with-technology-breeds-distrust-and-misunderstanding%E2%80%A6/
I hope that you will join me in feeling good about sharing a great tasting and healthy beef meal with your family!