On this page, we’ll discuss the most commonly-seen disorders specifically in the ISSA Shiloh Shepherd. Keep in mind that the most common disorder on this page, Canine Hip Dysplasia(CHD), still has an incidence rate of only 5.4%. We hope to see a further drop in many of these disorders as we progress with our outcrossing program. In addition, we would like to note that 10 out of 11 of the genetic factors listed for our breed by Embark in their DNA profiles are not present in the ISSA Shiloh Shepherd. The only one of those that is present is Degenerative Myelopathy (DM).
MOST COMMON
Canine Hip Dysplasia (CHD) – Hip Dysplasia is one of the most common disorders across all dog breeds. It comes in grades from borderline through severe, with marginal and mildly-affected dogs often not showing clinical signs until they are advanced in age. Despite this being our most common disorder, Shilohs have fairly good hips. The Shiloh Shepherd (all registries) is currently showing an incidence rate of 15% in the OFA database (from the last complete data period, 2016-2020), and roughly two-thirds of those dogs were only mildly affected.
The ISSA has its own records. As of the current day (Oct 16, 2024), we have 167 results entered into the ISSA registry. Of those dogs, we have only 9 affected results (3 borderline, 4 mild, 2 moderate, 0 severe). That makes the ISSA’s incidence rate only 5.4%! This is utilizing data from 2016, when we were established, through today (the ISSA’s 8-year anniversary), and includes both OFA and PennHIP.
For comparison, the Belgian Tervuren (a breed we recently outcrossed to) has an amazingly low incidence rate of only 2.6%! In outcrossing to breeds with better hips, we are following in the steps of what our breed founder originally sought to do with the outcrossing that created the Shiloh.
German Shepherd Dog Inherited Ventricular Arrhythmia (GSDIVA) – Shilohs originally came from a modified German Shepherd breeding program, and unfortunately this disorder came with it. This disorder is due to a misfiring of the nervous system rather than any structural problem—a GSDIVA heart looks perfectly normal, physically. This disorder causes irregular heartbeats which, in extreme cases, lead to cardiac arrest in young dogs (typically 5-12 months). After two years of age, affected dogs outgrow the disease and are no longer at risk. Holter monitoring is the only way to detect GSDIVA, and we have found that it is most likely to detect the disorder if we holter between 5.5 and 8 months of age.
This disorder is particular to German Shepherds and breeds derived from them, and is one reason we choose to outcross to other breeds. Death from GSDIVA is rare, but the ISSA strives to holter every pup from every litter in the hopes of rooting out all instances of this disease so that we might never see another death again. The ISSA also pioneered the recent study with NCSU seeking to find the genes that cause GSDIVA, though the study has been so far Inconclusive.
Exocrine Pancreatic Insufficiency (EPI) – A disorder where the pancreas stops producing the hormones needed to digest food. Affected dogs lose weight even as they eat more and more. Diarrhea is a common symptom, but a TLI test is needed to confirm the disorder. Treatment involves adding hormones to the food so that it can be digested. Once treatment is managed and a dog becomes stable, most have a good quality of life and normal life expectancy. EPI is a disorder we are specifically combating with outcrossing, and we are hoping to see much less of it as we integrate the Poodle/Wetterhoun, Tervuren, and Samoyed.
Sub-Aortic Stenosis (SAS) – The main structural heart disorder in Shilohs, SAS is due to malformation rather than a nervous system issue. SAS is present in many dog breeds, especially large dog breeds. Not all heart murmurs in puppies are a sign of SAS; some are innocent murmurs that disappear with age. However, if a murmur doesn’t disappear, a cardiologist can usually confirm the cause after six to eight months of age utilizing technology such as an echocardiogram.
The ISSA is making a special effort to get away from SAS when choosing dogs for its outcross program. SAS is present in most larger dog breeds, so we have made an effort to work with breeders who have decades of experience in their breeds and who can assist us in finding clear lines to work with.
LESS COMMON
These disorders still occur in the breed, but are less common than those above.
Gastric Torsion (Bloat) – A disorder in which the stomach twists, eventually killing the organ. Risk generally increases with age. Most large, deep-chested breeds are prone to bloat. Much research has been done, but the causes of bloat—other than a correlation with affected close relatives increasing a dog’s risk—are still a mystery. We see a few cases per year of this Disorder.
Cancer (various kinds) – There is no one type of cancer that predominates in the ISSA Shiloh at this time. We have seen hemangiosarcoma, anal sac cancer, bone cancer, and tumors of the reproductive system. Most cancers seem to affect our dogs in old age (10-12 years). We are tracking the incidences of early-aggressive cancer to hopefully lessen the occurrences. We specifically chose the Samoyed for our most-recent outcross because of the lower incidence of cancer and long lifespan of this breed (12-15 years).
Chronic Superficial Keratitus (Pannus) – An eye condition which onsets later in life (usually between the ages of four and six) and which can cause slow blindness if untreated. Treatment involves daily eye drops and dogs in which the condition is caught and treated live normal lives. We see a couple of cases per year.
Spondylosis and other lower back issues – As they get older, many Shilohs are prone to back issues and weakness in the rear. The ISSA has recently focused on breeding back toward a 9:10 body ratio of height to length to attempt to help this, as dogs who are very long in the body may be at higher risk. Many of our outcrosses should help with this.
Elbow Dysplasia (ED) – Elbow dysplasia is uncommon in the Shiloh—the OFA records give the incidence as only 5.8% for the 2016-2020 testing window, and, as with hips, most dogs are only mildly affected.
EXTREMELY RARE
There are a number of much more rare disorders that we see every once in a while. Of those below, DM seems to have been eliminated thanks to the DNA test. The ISSA has not seen a case of confirmed DM in over 15 years.
Degenerative Myelopathy (DM) – The only disorder in Shilohs for which a DNA test is available. We have only a handful of DM carriers left in our gene pool currently, most in frozen semen. DM leads to a loss of strength and then control in the hindquarters of the dog, progressing eventually to complete paralysis, and is caused by lesions in the spinal cord. Several disorders produce DM-like symptoms, and DM is often misdiagnosed when a different condition is the culprit. Only a spinal cross-section after death can truly confirm the disease, as the DNA test is considered reliable but not 100% so.
Mega Esophagus (Mega-E) – A condition where an enlarged esophagus causes food to be retained and sometimes aspirated into the lungs. Not all mega-e is genetic, but the genetic form has appeared in Shiloh Shepherds of the past. We haven’t seen a confirmed case of this for about ten years now.
Epilepsy – A seizure disorder that often manifests later in life (4-6 years of age). Epilepsy can be of various grades of severity, and anti-seizure medications can be prescribed to combat it. This disease is quite rare in our breed; it disappears, often for up to a decade, only to pop up again.
Demodectic Mange (Demodex) – An autoimmune disorder causing hair loss, inflammation, and scabby skin due to mites. All dogs have the mites, but a weakened immune system gives them the more extreme reaction. Many dogs who manifest the disorder as puppies outgrow the condition, but not all do. We are hoping that outcrossing will strengthen our dogs’ immune systems, and result in the elimination of this disorder.