The season of ripgut and painful vet bills is here. Foxtails, a longtime scourge in the West, can now be a problem in every state. And climate change may add a twist. Studies find that weeds grow faster under elevated atmospheric carbon dioxide; will migrate northward and are less sensitive to herbicides. A botanist who researched their effects on dogs also warns about a deadly disease.
Sporting dog owners may know it best since field dogs routinely charge into thick brush, where they easily inhale or swallow foxtails, and spend hours in grassy hotspots. But dogs playing in the park or yard, hiking, at a roadside stop; any dog, wherever foxtails live, can develop grass awn migration disease.
It begins with a jagged seed. Of the many kinds of foxtails, both native and non-native, only some have harmful barbs. Among them: foxtail barley, found nationwide except in the South Atlantic and Gulf Coast states, according to the U.S. Forest Service; cheatgrass; giant foxtail, and ripgut brome, named for its effects on livestock. The spring through fall season often starts in May, when the green, bushy awns turn brown and seeds disperse. Their spikes help them burrow into soil or be spread by animals. They can also dig down in fur and puncture skin. The foxtail, which carries bacteria, may then keep tunneling into tissue, carving the dangerous path of infection that marks grass awn disease.
The disease is very difficult to diagnose, says University of Wyoming botanist William K. Lauenroth, who studied its occurrence in ten Midwestern states, where field dog owners believe there’s been a sharp rise in cases. One reason it’s hard to pinpoint is that the infection occurs behind the migrating seed.
Many infections show up as an acute illness, according to the findings of Wisconsin resident Cathy Lewis, whose website meanseeds.com provides case histories and information about foxtails and grass awn disease. In 2013, her Springer Spaniel “XL” developed a mysterious respiratory ailment that required draining fluid from his lungs. It began during an outing in January; not the time of year when foxtails come to mind. But the website of Atascadero Pet Hospital in California says they’ve seen pets with “a recurrent abscess that is ongoing for 2 years and once the foxtail is removed the abscess goes away.”
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In fact, no plant material was found to confirm XL’s condition. But Lewis has had several other dogs with grass awn infections and recognized the signs, however vague. Today XL is “doing fine,” Lewis says. “He’s back to running field trials, and placing.” That may be due to how quickly she acted on his symptoms: labored breathing, high temperature and lethargy.
Vets say the dog’s body can’t break down the plant material. Sometimes, a foxtail lodges and causes a localized infection. But when it migrates, its barbs keep it moving on a one-way journey to almost anywhere, even the brain. Organs can be pierced, fungal infection can arise, and bacteria pack an extra punch deep inside the body. Head shaking or muscle movement propels it onward. Breathing can draw it further into nasal passages. Inhaled foxtails can travel from the nasal cavity to the lungs; a common site in working field dogs.
But what about the urban hound or beach bum pup? One study of grass awn migration found the most common site in all dogs was the external ear canal. Others were feet, eyes, nose, lumbar area, and thoracic cavity. Warning signs, if any, include extreme sneezing, head-shaking; coughing; excessive licking of a skin puncture, and a high temperature.
According to Dr. Jeffrey Horn’s veterinary blog, “foxtails are very hard to find due to their small size and because they’re covered with infection and scar tissue, and are completely invisible on X-Rays.”
Sporting dog owners hope to make it easier to diagnose and treat grass awn. Lauenroth, who trains retrievers, pursued the matter with a grant from the AKC and sporting dog groups. They suspect barbed grasses, especially Canada wild rye, planted in the U.S. Department of Agriculture’s Conservation Reserve Program have caused more cases. The grasses occur on lands where field dogs train and trial. The program pays farmers to let idle cropland provide ecological services, such as erosion control and wildlife habitat. The farmers plant approved native grasses and comply with mowing restrictions.
Lauenroth found that plenty of Canada wild rye has been planted in the Midwest, and its sharp awn makes it dangerous for dogs. Canada wild rye is also common along the east coast, he says. But the study dried up due to a dearth of definitive diagnoses to draw on. For vets, finding a foxtail seed in a dog is like searching for a needle in a haystack. Lauenroth says he was unable to extract numbers of cases over the past 20 years from the records of veterinary hospitals.
What he found were many “foreign body” cases without resolution. Many of those may have been grass awn disease. A study in 1983 found that grass awn migration in dogs and cats accounted for 61 percent of all foreign body-related cases. Most involved dogs.
To make foxtails more visible, vets often suggest giving dogs a close shave called a foxtail haircut. Others swear by headgear that is truly a pup tent: foxtail hoodies, designed to keep mean seeds out of eyes, ears and mouths.
Lauenroth’s advice is to thoroughly brush and comb after outings. The seeds don’t instantly disappear into the body. Also, get to know the few dangerous grass plants in your area.
In foxtail zones like California, it can also mean getting to know other dog owners: many outings at park and beach end with a festive foxtail-pulling party.