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Deworming Crucial To Maximizing Performance

published: October 6th 2008
source: Pfizer Animal Health

STERLING, Colo. - Pat Owens couldn't figure out what was
wrong with his calves. He used a pour-on deworming product at receiving,
but the calves weren't performing. Rough hair coats, droopy ears and
little weight gain were all symptoms that something wasn't right.
    Owens, a cow/calf producer and stocker operator in Sylvania, Ga., pulled
fecal samples and sent them to his veterinarian. The results showed the
calves were carrying a high parasite load.
    "In our area there has been ongoing discussion about which products are
better, and which method is more effective," says Ray Hicks, Screven
County extension coordinator with University of Georgia. "I was called
in to help and conducted a small comparison at Owens Farms with 25
head."   

Consistent with other studies, Hicks found that using Dectomax(r)
resulted in better weight gains compared to a generic ivermectin
product. However, no matter which product you use, including deworming
in your animal health practices is an important step.

 Importance of deworming
    Parasites are found in almost all forage situations, and your cattle are
ingesting parasites if they are grazing pastures.  Parasites cause
numerous problems, including depressed immune systems in cattle, making
cattle more susceptible to disease challenges.
    According to Gary Sides, PhD, cattle nutritionist for Pfizer Animal
Health, Sterling, Colo., parasites require cattle to complete their
lifecycle. "The purpose of strategic deworming is to treat cattle in a
timely manner to reduce the total parasite load on pasture," he says.
    "This reduces total exposure of parasites to all cattle on that
pasture."
    John Lawrence, director of the Iowa Beef Center, conducted an economic
analysis of pharmaceutical technologies, and found that parasite control
in the cow herd has a significant impact on calf production and cost to
the beef system. In fact, parasite infestation in a cow herd can cost
more than $200 per cow/calf pair through production and reproductive
losses.
    "Those internal parasites also suppress appetites, which limits nutrient
intake and absorption," Sides adds. "Reduced nutrition impacts animal
performance including gain, feed efficiency, immune response, and
reproduction."
    These losses can be minimized by using a dewormer before pasture turnout
in the spring, and again in the fall. Rodger Schroeder, manager of
Schroeder Operations in Chugwater, Wyo., says deworming in the spring
helps clean up external parasites. "In the fall, when we preg-test our
cows, we deworm them again. We've found that they just do better through
the winter when we use Dectomax in the fall."
    But, the decision on what dewormer to use can be as important as
deciding to implement a deworming program.

Choosing the right dewormer
    According to Sides, a recent trial comparing Durvet, which is a generic
ivermectin pour-on, to Dectomax Pour-On was conducted on steers
purchased from a single pasture in California. Cattle were fed for 162
days and harvested at a local packing facility.
    The study found that at days 14 and 30, fecal egg counts were
significantly lower in the cattle treated with Dectomax vs. Durvet. The
parasite data also showed Durvet wasn't as effective at eliminating
Osteragia adults (brown stomach worm), killing only 63 percent, while
Dectomax killed 94 percent of the adult worms.
    At the end of the study, researchers also found an average of a 22 pound
per head increase in live weight in steers treated with Dectomax
Pour-On, which in today's market is worth about $20 per head.3 "The
results show that Durvet just wasn't as effective as Dectomax," Sides
concludes.
    Dectomax can produce positive impacts in any type of operation, not just
feedyards. "We've seen anywhere between a 20- and 50-pound increase in
the weaning weights of our calves when we use Dectomax," notes
Schroeder.
    "Dectomax may be more expensive than other dewormers. But, at the end of
the day if the ivermectin product doesn't perform, you could be losing
$20 per head at the feedyard level," Sides stresses. "In this instance,
price shouldn't be the deciding factor. It is the performance that
matters."  And if parasites are not controlled on pasture cattle,
reproductive and weaning weight losses may be even greater.