You've reached the Virginia Cooperative Extension Newsletter Archive. These files cover more than ten years of newsletters posted on our old website (through April/May 2009), and are provided for historical purposes only. As such, they may contain out-of-date references and broken links.

To see our latest newsletters and current information, visit our website at

Newsletter Archive index:

Virginia Cooperative Extension -
 Knowledge for the CommonWealth

The Cow-Calf Manager
Implanting -- A tool you shouldn't forget!

Livestock Update, April 1999

John Hall, Extension Animal Scientist, Beef, Animal and Poultry Sciences, Virginia Tech

Calving season will soon be over for spring calving herds, and both spring and fall calving herds as well as stockers are looking forward to turnout. It is important not to overlook the value of implanting. For some reason in recent years, we have seen a decline in the amount of cow-calf and stocker operations that are using implants. Implanting is one of the practices that give the greatest return per dollar invested. Recently, several county agents and I conducted some on-farm research and demonstration projects on implanting. Producers could either compare implant to implant or implant vs. no implant. We are still analyzing the implant vs implant data, but lets talk about the results from the implanting vs no implant studies. Over 300 calves from 5 different counties representing 9 different contemporary groups were used. Implanted calves gained 0.16 pound per day more than un-implanted calves. That may not sound like much, but Table 1 illustrates what that can mean at weaning time in terms of pounds and dollars. Basically, it means $12 to $20 more per calf! And this was in a dry year. For implants to work best, plenty of good quality grass is needed. Other studies indicate increases in weaning weight of 30-50 pounds per calf for 2 implants.

Table 1. Expected increase in calf weight and value of calves as a result of implanting, based on results from 1998 Virginia Implant Demonstrations

 Implanted for
205 days
Implanted for
130 days
Extra pounds gained32.820.8
Increased value per calf19.6812.48

We can also look at the increase in returns to different sized operations. Table 2 shows increases in pounds marketed, increased value, and total returns. Table 2 also shows the difference between using 1 implant and 2 implants. In both Table 1 and Table 2, the average price per calf is $80/cwt, but the extra pounds are valued $ 60/cwt. The $60 figure is used because increases in weight due to implanting may throw calves into the next higher weight bracket. For example, an un-implanted calf that would weigh 580 lbs at weaning will weigh over 600 lbs if implanted and therefore bring less per cwt than the 580 calf. However, the total value of the heavier calf will still be greater.

The cost of implanting is estimated at $1.50 per calf. Implants cost between 60 cents and 1 dollar each. We estimate the labor cost of implanting calves at 50 cents per calf. Based on the estimates from these demonstrations, implanting calves on an operation that sells 30 calves can increase returns to the operation from $300 to $500 (Table 2).

Table 2. Increase in pounds sold and returns to different sized operations for implanting once or twice before weaning.

 30 calves50 calves100 calves
Increase in pounds sold (Implanted for 205 days; Implanted twice) 98416403280
Total increased value of calves sold $590.40$984.00$1968.00
Total return (value - cost)$500.40$834.00$1668.00
Increase in pounds sold (Implanted for 130 days; Implanted once) 62410402080
Total increased value of calves sold $374.40$624.00$1248.00
Total return (value - cost)$329.40$546.00$1098.00

Implanting is easy to do and can be learned in only one session with your extension agent or an experienced producer. Newborn calves can be implanted when you tag them. For older calves, a head gate will be needed to implant successfully. Don't forget to clean implant needles between each animal.

For cow-calf producers, there are basically three implants to choose from -- Ralgro, Synovex-C and Component-C. All of these can be used on calves still nursing their dams. Ralgro can be given at birth whereas you need to wait until calves are at least 45 days old to use Synovex-C or Component-C. These implants last about 90 days so calves implanted at birth to 45 days should be re-implanted at mid-summer deworming for maximum results. I encourage commercial producers to castrate and implant all male calves at birth.

Producers often ask if heifers should be implanted. A large volume of research reveals that 1) heifers should not be implanted before 2 months of age, 2) heifers should only receive one implant. Implanting heifers before they are 2 months old can result in severe reproductive problems. My recommendations on heifers are:

  1. If replacement heifers can be identified at birth do not implant.
  2. If the heifer may be used as a replacement, but might be sold as a feeder, give her one implant after she is 2 months old.
  3. If she will only be sold as a feeder, implant her at birth and 100 days later.

Steers vs. bulls. Years of research have demonstrated that implanted steers will gain just as fast as bulls. In fact at one of our locations last year, implanted steers out gained the bulls. But I would normally I would not expect any difference. Bulls will gain faster than un-implanted steers.

Finally, implants do not significantly raise the hormone levels in the final product. Research from several institutions, including the University of Minnesota, indicates little difference between hormone levels in implanted steers and "organically" raised beef. In fact, hormone levels in meat from bulls (the primary meat animal in Europe) and cows is higher than meat from implanted steers. Eggs have much higher estrogen levels than meat from implanted animals.

Implants are economical, safe and easy to use. They can add considerable income to the cow-calf operation. Let's not forget to use these tools this spring.

Visit Virginia Cooperative Extension