With proximity to several confined animal facilities, internal parasites could easily threaten Steve Olson’s commercial and registered Angus operation. But through a detailed deworming program, he keeps the mini-menaces from thwarting animal appetites and preventing top performance.
Olson’s ranch and farm are just south of Hereford, Texas. Steve; his father, George; his wife, Ginger; and their family have been in the Angus business since the 1980s. Half the operation is a registered seedstock program and half is a commercial cow-calf operation.
“Being in the Hereford area, we’re located in the middle of cattle feeding country and near an influx of dairies,” Steve says. “Pressure from diseases and other health problems is greater than some other ranches. Needless to say, we take numerous precautions to maintain strong animal health in all ends of our cattle program.”
Cows and heifers for breeding are vaccinated against bovine viral diarrhea (BVD), bovine respiratory disease (BRD) and other diseases that can cause stress, reduce their production of colostrum and hurt their overall reproduction. Just after birth, calves are placed on a scour-prevention protocol. At branding, they receive a modified live vaccine to further protect them against disease.
“We give another round of vaccines at preweaning,” Olson says. “To help assure that the calves can take full advantage of the vaccines, we also start our parasite control program at preweaning or weaning.”
In the past, Olson has used a pour-on dewormer to handle internal parasites. “But the pour-on stopped working as efficiently as we needed,” he says, noting problems seen by other producers who have experienced possible parasite resistance to dewormers. “So we started using an injectable wormer the past year.”
Olson says potential parasite problems are easily noticed in cows and calves. “The immune system is impacted negatively,” he says. “For females, if they are experiencing internal parasites, they may not be in bloom and won’t breed well. Your conception rate would be hurt. Milk production will suffer, which will impact how well the calves do.
“Performance of calves will also suffer. If they’re not given every opportunity to achieve their genetic potential, their weaning weight will likely be lower and their quality may suffer,” he says.
Parasites typically thrive more in warm, wet conditions. But even though Olson’s ranch is in a semi-arid climate of the Texas Panhandle, they can still attack a herd. Parasite eggs deposited in manure can easily infiltrate a pasture.
Different parasites are found in different climates and even neighboring pastures. The nastiest include lungworm, nodular worm, brown stomach worm, stomach hairworm and small intestinal worm.
Lee Jones, a veterinarian, associate professor and veterinary field investigator at the University Of Georgia College of Veterinary Medicine, says a parasitic relationship exists when one organism (the parasite) benefits at the expense of another organism (the host). “The parasite may cause harm to the host, enough to kill it if not properly controlled,” he says.
“Parasites can damage and irritate stomach and intestinal linings or mucosae, resulting in reduced digestion and absorption of nutrients from the intestine, as well as bleeding and protein loss from the gut,” Jones says.
In many cases, the brown stomach worm, Ostertagia, is possibly the most damaging. It can penetrate the true stomach lining after being dormant. Cooperia, the small intestinal worm, is also considered a major parasite problem for the U.S. beef industry. Consult with your veterinarian to determine which worms are most common in your area.
Dale Schueler, a veterinarian practicing near Friona, Texas, is Olson’s consulting DVM. His testing indicates both the brown stomach worm and Cooperia are among the most common parasites found in the Southern High Plains. The region’s drier climate and cold winters help hold down numbers, as does grazing pastures that are not often used, such as Conservation Reserve Program land that can be grazed every three years.
“We’ve had success in using a wormer in the fall,” Schueler says, “unlike areas back East, where they see more treatments during the spring due to wetter summers.”
He advises producers not to skimp on parasite control. “With continued low cattle prices, we’ll probably see more use of generic wormers. That’s not a good way to obtain the control needed,” Schueler says. “It’s not as good of a product. We’re seeing better results with injectables.”
Schueler adds that a greater use of a “white wormer,” a fenbendazole, may be needed this year to handle a wider spectrum of parasites and reduce the chance of resistance. “The fenbendazole wormer is a totally different family of wormer, and its use is to lower possibilities of developing resistance to ivermectins, which have been our wormer of choice,” he says.
“We rotate using ivermectin wormers with wormers from the benzimidazole family, which includes fenbendazole, but there are others just as effective. Alternating with a white wormer every three years is a useful way to reduce resistance,” says Schueler.
He adds it is more efficient to make parasitic and other animal health treatments simultaneously when handling calves. “The whole package comes together more effectively, and cattle usually respond and perform better,” he says.
Olson points out that the pour-on was more convenient in its application. “All you had to do was treat cattle as they were moving,” he says. “With the injectable, now they are treated as they’re going through the chute. It takes more time, but the injectable is working well. We haven’t noticed any problems in the breeding program or with calves.”
Olson normally feeds the steers from his commercial herd to gauge their performance. “Just looking at the cattle, you know he has a good parasite control program. But it’s not just parasite control, it’s everything,” says Scott Keeling of Keeling Cattle Feeders in Hereford.
“They have good quality, and the cattle are calm. That makes them easy to work in the yard. They perform in the top 15% of the cattle we feed,” Keeling says.
Olson believes a good parasite program is nearly as important as a good vaccination program. “It’s part of a total animal health approach,” he says. “It seems like it takes more time to vaccinate and make other treatments than it used to. But I have less sickness at weaning than before. A good worming program, along with booster vaccinations at weaning, helps calves perform better.”
Stalcup writes from Amarillo, Texas.