Updated: June 29, 2021
By Charlie Sasscer

Implanting Pre-weaned Calves

Everyone loves a good return on their investment, though some old farmers might crack that you shouldn’t be in the cattle business for that. But for those of us cow/calf producers who are just too hooked on raising nature’s most perfect bioreactors, there are countless technologies available for ensuring that our four legged friends are at the very least paying their own maintenance bills. Steroidal calf implants are one such technology that have been proven to provide a return on investment that exceeds even the most lucrative of business endeavors.

Calf implants work in several ways, depending on which active ingredients are present. Estradiol, estradiol benzoate, and zeranol implants all have similar function in growing calves, which is to promote the hypertrophy, or growth in size, of muscle cells. This leads to increased muscle deposition. Implants containing progesterone promote the consumption of more feed which provides more nutrients for growth and development. Both modes of action are very similar to the hormones naturally produced in the bodies of calves, especially in bull calves, as estradiol is the precursor hormone which testosterone is made out of. When used in combination with castration at 60 days of age, similar or greater weaning weights can be achieved in implanted calves verses non-castrated bull calves. Additionally, this removes the stress that comes with waiting until weaning to castrate bulls. While known replacement heifers should not be implanted, heifer calves can also be implanted while on the cow to achieve increased weaning weights while also not compromising their reproductive efficiency later in life.

The price of calf implants starts at around $1.30/implant, and each calf only needs one. Implants have been proven to increase calf average daily gain (ADG) by 5% or more over the 120 days from implantation to weaning. That equates to 0.1 lbs. /d, or an extra 12 lbs. of growth. Using a rough estimate for sale price of $1.50/ lbs., this can result in an additional $18.00 of calf value, all from a little more than a dollar investment. Furthermore, returns from implants can be even more significant based on genetics, nutrition, and calf prices.

Many producers and organizations oppose the use of growth promoting implants in cattle, due to their beliefs that utilizing estrogenic implants results in beef with much higher levels of hormones. However, this is untrue. Beef from implanted animals contains an average of 11 nanograms of estrogen per 500 grams of food. This is a non-significant increase compared to beef from a non-implanted animal which contains 8 nanograms of estrogen per 500 grams of food. In comparison, cabbage contains 12,000 nanograms of estrogen per 500 grams of food. If you were to slice 1 grain of rice into 25 million parts, one of the 25 million parts would weigh one nanogram. That is how safe beef from implanted cattle is.

Several considerations should be made for cow/calf producers that wish to implant their suckling calves. First off, calves must be restrained in a headgate or roped and stretched out to safely immobilize them. Second, not all types of implants are available in quantities feasible for small producers. While, Synovex C implants by Zoetis are a great choice, they are generally only available in packs of 100 doses. This issue can be solved by several producers working together to split a package, as implants come with an expiration date. For independent, small producers Component E-C implants may be a great option as they come in 20 dose cartridges, or the more traditional Ralgro implants may work well as they come in 24 dose cartridges. Each brand of implant has their own specific implant gun needed to apply the implants and these run about $20. Finally, most implants need to be refrigerated, so they will be shipped in a Styrofoam container and will then need to be refrigerated.

Implants are administered into the backside of the ear of calves, and it is best to watch tutorial videos online, or to ask your veterinarian or local livestock extension educator for a demonstration. It is important to utilize antiseptic techniques such as cleaning the implant needle between calves and cleaning the calf ear before puncture. Utilizing calf implants is a cost effective and easy way to increase protein deposition, growth rate, and improve feed efficiency. Overall, this can result in a seven percent decrease in the cost to produce beef.

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This article appears in May 2021 (Edition 1), Cattles Tales Livestock newsletter.

Cattle Tales Livestock Newsletter, May 2021, Edition 1

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