The Boxer's most notable characteristic is his desire for human affection. Through his spirited attitude, square jaw, and cleanly muscled body suggest the well-conditioned middleweight athlete of dogdom, the Boxer is happiest when he is with people--especially children. His short smooth coat, handsome chiselled head, and striking silhouette never fail to excite comments from passersby as he trots jauntily by your side with neck arched and tail held erect. Yet the Boxer's greatest wish is to be with children, watching protectively over their play. He is truly a "dog for all seasons," suiting the need for household guardian, attractive companion, and children's playmate and loyal friend.
The Boxer's official classification in the "Working Group" of dogs is a natural. His keenest sense, that of hearing, is enhanced by the cropped, erect ears and makes him an instinctive guard dog, always alert. He has also been used as a courier during war time, and as a seeing-eye dog for the blind. Although always vigilant, the Boxer is not a nervous breed, and will not bark without cause. He has judgment, and an uncanny sense of distinguishing between friend and intruder. One of the delightful qualities that sets the Boxer apart is the unique mobility of his expressive face. The skin furrowing of the forehead, the dark, "soulful" eyes, and at times almost human attempts to "converse," make his replacement by another breed difficult for one who has owned a Boxer. He mimics the mood of his master and can spend hours quietly lying at his feet.
Unfortunately, the Boxer is susceptible to several potential health problems, below is a short list of those conditions most common in the boxer breed.
- Major concerns: cardiomyopathy, SAS, CHD
- Minor concerns: gastric torsion, tumors, intervertebral disc degeneration, corneal erosion, colitis
- Life span: 8 - 10 years
- Note: sensitive to heat and anesthesia. See info below on Acepromazine
Hip dysplasia is the number one cause of hind limb lameness in dogs and results in an arthritic condition of the hip joint which is initially caused by a laxity (looseness) in the hip joint itself. This joint is a ball and socket joint in which the head of the thigh bone (femur) fits into a cup-like depression (acetabulum) in the pelvis. The laxity is associated with the tissues which surround and hold the joint in place, that is, the tendons, ligaments, connective tissue, and muscle, and this laxity leads to bony abnormalities of the ball and socket. While the laxity of the joint is not thought to change much with time, the presence of joint instability causes abnomal wear and tear on the cartilage lining of the joint with subsequent development of arthritis as the dog ages.
Indeed, the Orthopedic Foundation for Animals (OFA) believes that there is little change in the test for dysplasia after 4 months of age; however, they require testing at two years of age or older for certification purposes, to err on the side of caution.Clinical signs can be extremely variable -- from no symptoms to severe lameness. Severity of arthritic changes on radiographs (X-rays) does not necessarily correlate with degree of lameness.
Diagnosis is made from radiographs of the hip joint (from the pelvis to the kneecap) and does require sedation or anesthesia. Positioning of the dog is critical for proper evaluation. The radiographs are evaluated by veterinary radiologists specially trained for this task. The dogs are graded as excellent, good, fair, borderline, or mildly, moderately, or severely dysplastic.
A newer method of evaluating hip joint laxity called PennHIP has been developed at the University of Pennsylvania School of Veterinary Medicine. This involves a different method of positioning the dog and uses a distraction device that is fitted to the dog during the procedure. Three views are taken, including a compression view, a distraction view and the standard (OFA) extended view. From the radiographs, the dog is assigned a DI or distraction index from 0-1.0, with values of 0.3 or below considered NOT at high risk for developing dysplasia. The dog is also ranked with other members of its breed in a percentile. (A dog ranking in the 80th percentile has 20% of its breed showing tighter hips.) This test can be performed at 16 weeks of age, but the originators of the method admit greater reliability if the test is performed later (at one year).
Hip dysplasia is thought to be genetically determined in part, but the mode of inheritance has not been established, since multiple genes and environmental factors such as nutrition and rapid growth may play a role in its development.
While some have questioned the frequency and severity of hip dysplasia in the boxer, many owners are now testing their dogs. The OFA currently reports the boxer as 67th in incidence of dysplasia (among breeds where over 100 dogs have been tested) with 2.9% of boxers testing excellent and 11.3% dysplasitic. The OFA Web Site at www.offa.org, or the PennHip website at www.vet.upenn.edu.html are sources of additional information. This and other information is best discussed with your own veterinarian.
Thyroid Disease in Boxers
Thyroid disease in the boxer occurs primarily as hypothyroidism, or impaired thyroid gland function with low thyroid hormone levels. It often develops slowly over several months or years. The animal's body, for as yet unknown reasons, forms antibodies against its own thyroid gland resulting in partial or complete destruction of the gland and the subsequent inability to produce adequate thyroid hormone.
Many breeds, including the boxer, seem to be genetically predisposed to hypothyroidism. Affected animals may be listless, develop coarse haircoats, have significant hair loss, gain weight, experience infertility and/or fetal resorption or show neurologic problems. In some cases, abnormal test results may preceed the clinically apparent stage of the disease. A simple thyroid test (T4) obtained from your veterinarian is often inaccurate and can give falsely low readings in normal dogs with concurrent non-thyroid illness and normal values when thyroid disease is in the early stages.
More definitive testing may be obtained by performing a panel of tests which include Total T4, TGAA (thyroglobulin autoantibodies), cTSH (canine thyroid stimulating hormone), so-called "free T4 by equilibrium dialysis," and sometimes T3 and free T3. This panel is currently not available from all diagnostic laboratories and must be sent to one of several reference laboratories by your veterinarian. Repeat testing may be recommended at regular intervals, because the disease can be slow to develop and current test results may not predict future abnormalities. Your veterinarian may not feel the need for these additional tests if the dog has no clinical signs of hypothyroidism, but owners who suspect their animals of being hypothyroid despite normal values on simple T4 tests and/or those who suspect an hereditary condition due to knowledge of affected relatives may wish to pursue more definitive testing as a screening mechanism in consultation with their veterinarian.
One of the most common causes of sudden/unexpected death in boxers, both young and old, is a condition thought to be inherited and characterized by abnormal heart rhythms involving the ventricles (the main blood pumping chambers) of the heart. This condition can cause varying degrees of disability and occasionally results in congestive heart failure. Current research has determined that the disease is the result of an electrical conduction disturbance which causes the heart to contract too early, thus producing an extra, ineffective beat, the so called Premature Ventricular Contraction (PVC). While many dog breeds may have a few of these PVC's, the boxer seems to be prone to having more of these premature beats. When large numbers of these PVC's occur together, the heart muscle cannot produce a normal, effective contraction, which results in a lack of blood flow to vital organs including the brain and the heart itself. This can cause the animal to experience a seizure-like or fainting episode (syncope). A prolonged sequence of PVC's can lead to complete cardiac arrest unless the heart resumes a normal pattern of contractions. Less commonly, the lack of adequate contractions may cause the heart to fail and the dog's heart may dilate, causing congestive heart failure with symptoms such as shortness of breath, exercise intolerance, abdominal swelling, coughing and symptoms similar to those occurring in humans with heart failure. This is known as dilated cardiomyopathy —a less frequent condition in the boxer than the more commonly seen electrical conduction defect.
The definitive test for this disease would be a DNA test for the abnormal gene. This research is currently underway at Ohio State University, but research of this type can take a considerable amount of time and funding. Since affected dogs are often asymptomatic until a seizure or sudden death occurs, current attempts in screening for the disease are directed at the healthy appearing animal. The most sensitive tool has been determined to be a Holter Monitor examination (24-hour EKG), which records the dog's electrocardiographic activity over at least 24 hours. The monitor is strapped to the dog and electrodes are placed on the chest while the dog goes about its normal activities. The total number of beats, including the abnormal PVC's, are recorded. The electrodes must be correctly placed and the results must be interpreted by trained personnel. While current research at Ohio State University by Dr. Kate Meurs, funded by the American Boxer Charitable Foundation and the AKC Canine Health Foundation, has suggested certain thresholds of PVC's or other abnormalities for diagnosis of the condition, she has also discovered that an individual dog's numbers may vary from day to day or week to week. Her ongoing research, and that of others, will hopefully determine with greater certainty the value of this screening tool in the future until a definitive genetic test is available. While it is true that a symptomatic dog usually has thousands of beats in a 24 hour period and in severe cases may be diagnosed by simple auscultation of the heart or by a brief EKG, the Holter monitor is still probably the best screening tool for early detection, due to the often intermittant occurrance of the PVCs in the asymptomatic dog.
Of recent interest to boxer cardiology researchers is a somewhat similar condition found to occur in human families, the so-called arrhythmogenic right ventricular dysplasia (ARVD), in which young and old persons, previously in good health, experience sudden death. To our knowledge, attempts to find a precise DNA marker have not been successful so far, but if this occurs, it may help veterinary cardiologists find the canine genetic defect sooner. BCM appears to be unique to boxers, so far, in the dog world, and is dissimilar in many respects to cardiomyopathy occurring in other breeds, such as the Doberman and Great Dane. Continuing research and follow-up of dogs already under study will hopefully provide better insight and understanding of this unique condition in the boxer, as well as more widespread availability of screening.
Aortic / Subaortic Valvular Stenosis: AS/SAS
One of the most common heart defects occurring in dogs, boxers in particular, is aortic or subaortic stenosis. In most cases the stenosis, or narrowing, is produced by a fibrous ring of tissue below the aortic valve, hence the term "subaortic." The disease is inherited but its mode of transmission is not known at this time.
Oxygen-rich blood flows from the left ventricle of the heart, through the aortic valve and into the aorta, which transports the oxygenated blood to all organs and tissues in the body except the lungs. Narrowing of the aortic valve requires the left ventricle to work harder to pump the necessary amount of blood. This increased workload can result in hypertrophy (thickening) of the left heart muscle. Since the blood is being forced through a smaller-than-normal opening, there is also increased pressure generated by the pumping action of the heart. This increase in pressure can cause dilation (ballooning) of the aorta. Reduced flow can produce symptoms of fainting (syncope) and even sudden death, although abnormal heart rhythms (arrhythmias) may also contribute to these symptoms.
The stenosis creates a change in the flow of blood through the valve causing turbulence which results in swishing sound called a heart murmur. Often the stenosis can be seen on echocardiography. Murmurs are graded from one to six, but a weak murmur may not always be detectable, even by a trained cardiologist. Exercising the dog during the cardiac exam may increase detection of murmurs in some cases. Not all murmurs are the result of aortic stenosis/subaortic stenosis, but may be so-called "innocent," or physiologic murmurs, particularly when they occur in young animals.
The diagnosis of AS/SAS is best made by a veterinary cardiologist, or one with equivalent experience and training. When a murmur is identified and not presumed to be physiologic, further investigation is warranted. The least invasive and most available testing consists of Echo/Doppler.This testing is best performed when the animal is full grown or at least one year of age, unless the dog is experiencing symptoms of heart disease, in which case testing should be pursued promptly.
As in many instances in medicine, these tests have limitations and are not perfect. False positive and false negative diagnoses may occur. In some cases this is simply because the abnormality is too subtle to be diagnosed with currently available knowledge and/or technology. Echo-Doppler flow rates can vary considerably in the same animal depending on the proficiency of the operator and the amount of stress to which the animal is subjected. These limitations may be minimized in part by examiners with advanced training using the appropriate ultrasound equipment, techniques, and standards established by the American College of Veterinary Internal Medicine, Specialty of Cardiology.
There is one drug used in anesthetic protocols that should not be used on the Boxer. That drug is Acepromazine, a tranquilizer that is often used as a preanesthetic agent. In the Boxer, it tends to cause a problem called first degree heart block, a potentially serious arrhythmia of the heart. It also causes a profound hypotension (severe lowering of the blood pressure) in many Boxers that are given the drug. Recently on the Veterinary Information Network, a computer network for practicing veterinarians, an announcement was placed in the cardiology section entitled "Acepromazine and Boxers". This described several adverse reactions to the drug in a very short time span at a Veterinary Teaching Hospital. All the adverse reactions were in Boxers. The reactions included collapse, respiratory arrest, and profound bradycardia (slow heart rate, less than 60 beats per minute). The announcement suggested that acepromazine should not be used in dogs of the Boxer breed because of a breed related sensitivity to the drug.
Further warning from a boxer breeder and veterinarian:
This drug is the most commonly prescribed tranquilizer in veterinary medicine. It is also used orally and is prescribed for owners who want to tranquilize their dogs for air travel. I would strongly recommend that Boxer owners avoid the use of this drug, especially when the dog will be unattended and/or unable to receive emergency medical care if it is needed. Wendy Wallner, DVM December, 1995
When you first take your boxer to a vet (or to a new vet), for any kind of treatment have them write in red on the outside of the patient record "NO ACE". Be firm! If they refuse to do this then I would immediately remove my dog and find another vet.
Don't be fooled by an uninformed vet...this is a matter of LIFE AND DEATH!