Prepare Cattle for a Winter Without Parasites

Deworming cattle in fall helps maintain health and condition

Whether marketing calves or caring for bred cows this fall, every cattle producer has to make the most of each pound of feed. So why feed parasites too?

“There is no reason to feed the cow, calf and the parasites,” says Gary Sides, Ph.D., Cattle Nutritionist, Pfizer Animal Health Veterinary Operations. “If you deworm, you’re making sure you’re feeding the growing animal and not the parasites. And, if cattle have been grazing on grass, they almost certainly have parasites.”

Producers could be losing as much as $3 billion annually in lost weight gains, poor feed conversion and increased disease due to parasites, Dr. Sides says.1 When cattle are infected with parasites, it can suppress their appetites, limiting the intake and absorption of nutrients.2 Plus, infections can mean cattle can’t fight off other diseases as easily.1

For cows, it’s important to maximize the gains made while on pasture and keep them in good body condition through winter. For calves, every deworming offers the opportunity for significant improvement in productivity.3

Dr. Sides recommends producers deworm cattle in the fall to help protect against Ostertagia ostertagi — or the brown stomach worm, and the most damaging internal parasite — and other parasites that can potentially rob cattle of performance and producers of profits.

For Dr. Sides, a broad-spectrum dewormer, such as DECTOMAX® 1% Injectable (doramectin) is the best option to help control Ostertagia and other internal and external parasites. In fact, DECTOMAX Injectable treats and controls Ostertagia for up to 21 days and is safe for pregnant cows, newborn calves and bulls.4

Come fall, producers in areas where biting lice are of concern may consider using a pour-on product, although
Dr. Sides cautions that injectable products offer more precision in dosing and administration, which helps products be as effective as possible.

“With the producers I talk to, I tend not to be as concerned with the external parasites,” Dr. Sides says. “I’d rather control the internal parasites that can do the most to slow down growth and feed efficiency.”

Important Safety Information: DECTOMAX Injectable has a 35-day pre-slaughter withdrawal period. Do not use in dairy cows 20 months of age or older. DECTOMAX has been developed specifically for cattle and swine. Use in dogs may result in fatalities.

For more information, contact:

Becky Lambert
Pfizer Animal Health

Jennifer Ryan
Bader Rutter

1Bagley C, Healey MC, Hansen D. Beef Cattle Handbook: Internal parasites in cattle. Iowa Beef Center. 1999.
2Corwin RM, Randle RF. Common internal parasites of cattle. University of Missouri Extension. October 1993.
3Smith RA, Rogers KC, Huse S, et al. Pasture deworming and (or) subsequent feedlot deworming with fenbendazole. I. Effects on grazing performance, feedlot performance and carcass traits of yearling steers. The Bovine Practitioner. May 2000; 2(34): 104-114.
4 DECTOMAX Product Label.



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