Actinomycosis, Nocardia, Grass Awn Infections

Grass Awn, Spear Grass, Actinomycosis, and Nocardia infections are dreaded by those that are aware of the migration of grass awns through the body of the dog, and resultant infections. Actinomycosis and Nocariosis are infections caused by the injection, inhalation, or entry through the skin, of grass awns that over time develop into serious, difficult to diagnose infections in the dog. Sporting dogs are most at risk for this, as the upland bird habitat is nearly always dominated by grass. The symptoms are complex, and your awareness, and that of your veterinarian’s is important to the success of diagnosis and treatment. The best explanation of this disease for the general dog owner is Dr. Pat McInteer and Dr. Jim Mills & Others, Nocardia Infections in Bird Dogs (see attached). Please read it. It is important that you inform your veterinarian that your dog has been worked in the field. Grass awns are most abundant during the late summer or early fall; however, they can persist through the winter and spring, given the right conditions. If your dog is exhibiting symptoms (see McInteer) you must discuss the potential for grass awn infection with your veterinarian. Bacterial culture for these is more difficult than the routine test run in the lab, because these may take 10 days to grow, as opposed to the more common 3 days . Reliable veterinary sources agree that the incidence of these infections has been on the rise for the last two decades. There is a theory that the increase is associated with the higher populations of spearhead grasses in Crop Reduction Programs (CRP), and there is an ongoing study looking at this, funded by AKC Canine Health Foundation. The importance of awareness of grass awn disease cannot be overemphasized. Your veterinarian may not be aware of the potential, particularly due to the often non-specific symptoms, and also because this has often been an overlooked, uncommon illness, that has only recently increased significantly in incidence. You should always examine your dog thoroughly after you have worked with it. Check for lesions in the skin, face, mouth, ears and on the foot pads as well as between the toes. You must not assume this will detect all the grass awns that could make your dog sick, but this routine will also find ticks, cuts, or seed passengers. The coarse hair of the Griff precludes a thorough visual exam for the most part.

Be sure to read Dr. McInteer’s paper: Nocardia Infections in Bird Dogs

Links: Thomovsky, Elizabeth, Kerl, Marie. Actinomycosis and Nocardiosis. Vetlearn.com, april 2008 Volume 10.3. http://cp.vetlearn.com/Media/PublicationsArticle/SOC_10_03_4.pdf See also the Recommended Reading at the end of that paper.

AKC Canine Health Foundation funded research: Assessment of grass awn disease in dogs & CRP plants of grasses with barbed awns. http://www.akcchf.org/research/funded-research/1521.html