In recent years, those of us who hunt and train primarily in the Mid-West are seeing a significant increase in problems related to grass seeds, or “awns,” which, until the last few years, were only thought of as problems common in the Western states.
Yet, here in Iowa, we dealt with a very serious infection in one dog when an awn was identified in a lump outside her rib cage last summer. Then another case where one of our GSPs came very close to losing an eye, only saved when our veterinarian found a Canadian wild rye awn under her eyelid, working its way behind the eyeball.
With experiences like this, and what I’m hearing of unusual increases in the number of grass awn related problems, we felt it was time to give our GUN DOG readers a heads up on these potential hazards. Especially as we prepare for the spring and summer months when these grass seeds pose the greatest threat.
To help with the message, I’ve enlisted a good friend, Cathy Lewis. Cathy acquired her first field bred English springer spaniel in 1995. She and her husband, Dean Reinke (who got his start with springers much earlier), train, field trial, and occasionally breed their springers. Both are active with the ESSFTA, the springer field trial parent club. When one of Cathy’s trial springers, Tai, had recurring bouts of unexplained illness culminating in a pyothorax in 2005, Cathy was determined to find some answers about the cause. She’s become that much more involved as they have dealt with four more grass seed infection cases with their own dogs as well as learning of fellow trialers’ experiences. The ESSFTA established a committee to investigate the grass seed issue in 2007. Cathy was an initial member.
How Grass Seeds (Awns) Cause Infections Pieces of plant material, typically the seed (awn), penetrate the skin, or are inhaled or ingested as the dog runs through cover. The awns of the most problematic grasses are barbed, which allows the awn to ratchet itself along through the tissue. The awn may carry bacteria as it enters the dog’s body, and/or it may carry bacteria that are normal inhabitants of one part of the body, usually the mouth, into other parts of the body where it is abnormal, and establishes an infection, typically in the form of an abscess.
Foxtail barley, one known hazard, occurs most commonly in the western states but is now found throughout the United States. In the past few years, in the Midwest and Mideastern regions, Canada Wild Rye has been implicated in several canine infections. Some conservation groups and state agencies have favored Canada Wild Rye as a low cost “cover crop” for new conservation plantings that provides nesting habitat and feed for game birds. Virginia Wild Rye is a similar plant, but with a somewhat less aggressive awn.
This Foxtail Barley was pulled from the corner of a ‘fast food’ parking lot. You’ll find it growing all across the country. Foxtail awns are more commonly acquired through the skin, generally in the feet, ears, or nose, thus a careful inspection of the dog after leaving the field may allow removal and avert any illness. With awns that more likely have been inhaled or ingested, while a good going over after a workout never hurts, odds are that the damage has already been done by the time you and your dog leave the field.
What Are the Symptoms of a Grass Seed (Awn) Infection? One of the major dangers of a grass-awn infection is that symptoms can be very subtle until the dog is gravely ill. Knowing your dog and recognizing when he or she is “just a little off” is one of the best protections you can offer. Routinely check your dog for swellings, particularly at the lower rear sections of the rib cage, a prime site for abscess development. The dog may cough, show a loss of stamina, and in a more advanced case involving an infection in the chest and/or lungs, may show difficulty breathing. As we have experienced these infections in our dogs, I have learned to be very concerned about a temperature of around 104 degrees. This isn’t necessarily high enough to alarm your veterinarian, but it’s been a telltale sign in all of our cases.
Mature Canada Rye as it looks during hunting season. The highest value action you can take if your dog is “off” without other explanation is to get a chest x-ray/radiograph taken and closely monitor his/her temperature.
While all dogs can be at risk, grass-awn infections more typically affect working dogs. Unfortunately for many of us, our veterinarians are not necessarily up to speed on this sort of problem to where this is high up on their possibility list for differential diagnosis. Time may be of the essence when you realize that your dog may be affected, so your dog’s best chance may be you raising this as a possibility with your vet early. I suggest printing out some material now and asking your vet to put it in your file so that it is readily available if it’s needed.
How to Treat Infections from Grass Seeds (Awns) The best piece of advice on this issue that I’ve received to date comes from Dr. James Mills of Searcy, AR: “If you have even a remote suspicion that your dog has been exposed to hazardous plant material and your dog has symptoms with no other immediate cause, start treating the dog as though it has a grass awn infection until you can definitely determine another diagnosis.”
“The bacteria that cause these infections are typically anaerobic, which grow in an environment without air. This complicates specimen collection and culture growth, since exposure to oxygen may prevent or slow reproduction of the bacteria in the sample. Consequently, culture results are often nonspecific or incomplete. Commencement of treatment should not be delayed waiting for culture reports.”
In some cases, ultrasounds may be used in locating an awn, or at least identifying the tract the awn creates as it travels. A chest x-ray will likely be helpful, and blood work a matter of course to check for indications of infection.
An awn that migrates to the outside of the body and sets up an abscess may be a best-case scenario, though our experiences with this manifestation have both involved surgery. These abscesses commonly erupt towards the rear and to the lower edge of the rib cage. We’ve had two dogs with this type of symptom, and one lost the bottom few inches of the last few ribs because the abscess was both external and internal to the ribs. The second dog had two ribs removed entirely to remove her abscess, and also lost a 1- to 3-inch piece of her back muscle, which is where the offending awn was located and removed. Apparently, migration to the spinal region is also common.
An abscess or infection in the chest (pyothorax) or lung can be life threatening. Typically, these cases cannot be treated with antibiotics alone, the fluid and pus in the chest cavity will need to be drained.
How to Protect Your Dog Grass Infections Learn to recognize hazardous plants, and be watchful of where you are hunting, training, or even just exercising your dog. These plants are especially hazardous in late summer through fall as they dry out and the awns loosen and become more prone to drop. If you are in an area that may support foxtails, inspect your dog after he or she runs, to remove awns before they have the chance to penetrate the skin or lodge in the ear and begin to migrate.
Always take time for a tailgate check at the end of training drills and hunting to check your dog over, nose to tail. (Photo courtesy of Brian Grossenbacher) If you are an event organizer, be aware of the problem and avoid hazardous fields. Express your concerns to your local conservation groups. Seed mixes are available without rye grass, so be careful how you select your mix.
If you have rye grasses in your own fields, Nancy Pals, a conservation resource officer in Illinois recommends burning to weaken the stands and has also seen some success in reducing the amount of rye grass with overseeding with big and/or little bluestem.
