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Health

Weimaraners are relatively fit gundogs and most suffer from few illnesses during their lives. However, the incidence of bloat or gastric torsion is on the increase.

Bloat / Gastric torsion

This condition is the most common cause of mortality in young weimaraners. Gastric torsion (also known as bloat / gastric dialtation volvulus (GDV))   is caused by the rapid build up of  air in the stomach causing it to  become distended.  The  stomach twists, cutting off nerves and blood vessels, and puts pressure on other organs. The internal build up of pressure and the related shock causes death. Bloat can come on suddenly and without warning. It is a medical emergency and veterinary help should be sought immediately. Despite aggressive medical and surgical therapy, fifteen to 25 percent of affected dogs die. 

What to look for : restlessness, attempting to vomit without any success, distended abdomen, obvious pain.

Prevention
There are ways of reducing the chance of gastric torsion.     

  • give food in two small meals rather than one meal
  • soak dry food
  • never exercise a dog  within an hour or so of feeding
  • never feed late at night as bloat tends occur a few hours after eating
  • slow down a greedy eater by placing large stone in bowl
  • don't allow a dog to drink large amounts of water at once

Some people recommend the use of stands to lift the bowl from the ground as a means of slowly down the rate a which the  dog eats - however, research has found that raising the bowl seems to be a contributary factor. 

Research also indicates that the dogs most a risk are  males, over the age of three, with a tendency to be under-weight and/or living in a stressful environment.

Research notes

(these notes are based on the information that can be found on the Bloat Notes  webpages of Purdue University - more detailed information can be found at http://www.vet.purdue.edu/depts/vad/cae/research.htm )

Large and giant breeds of dogs in the US are experiencing an epidemic of gastric torsion. As a result, Purdue University is conducting a five year study into the incidence of gastric torsion in 2000 show dogs. Their aim is to identify breed and individual dog-related risk factors. Included were the following breeds: Akita, Bloodhound, Collie, Great Dane, Irish Setter, Irish Wolfhound, Newfoundland, Rottweiler, Saint Bernard, Standard Poodle, and Weimaraner. The deep and width of the chest of these dogs was measured at AKC shows and their owners completed a detailed questionnaire concerning their dog's medical history, genetic background, husbandry and feeding practices, personality, and diet. After five years of telephone follow-up, the incidence of gastric torsion was calculated for each dog breed. Risk factors for gastric torsion were identified by comparing the body measurements and questionnaire responses between dogs that developed gastric torsion with those that did not. 

The incidence of gastric torsion for the seven large (23-45kg) and four giant (greater than 45 kg) dog breeds was 23 versus 26 per 1,000 dog years at risk, respectively. Of the 105 dogs that developed gastric torsion, 30 (28.6 percent) died. The incidence of gastric torsion increased with increasing age. The cumulative incidence of gastric torsion was 5.7 percent overall, but was higher for the Great Dane (15.7 percent) and Bloodhound (8.7 percent) breeds. The only breed-related characteristic significantly  associated with a decreased risk of gastric torsion was a higher score for being happy, as reported by the owners. Non-dietary risk factors associated with an increased risk of gastric torsion in individual dogs included having a larger abdomen depth/width ratio, being underweight, and having a sibling or offspring with a history of gastric torsion. Additional potential risk factors for gastric torsion including those related to diet are currently being explored. 

The six breeds with the highest incidence of gastric torsion decreasing order were the Great Dane, Akita, Bloodhound, Weimaraner, Standard Poodle, and Irish Setter. For the 216 Great Danes that had an average follow-up time of only 2.5 years, nearly 12% developed gastric torsion. Assuming that these Great Danes live to be 10 years of age, the research team  conservatively estimated that more than 50% will eventually suffer an episode of gastric torsion!! This is quite alarming given that nearly 25% of dogs can be expected to die during or shortly after an episode of gastric torsion and it is consistent with previous findings that gastric torsion is one of the leading causes of death in many giant and large breeds of dogs.

The table  below  the number of dogs in some of the breeds enrolled as of November 14, 1996. This table also shows the bloat risk of each breed relative to the risk in mixed-breed dogs, who are arbitrarily assigned a risk of 1.0. Thus the breed risk of 41.4 for the Great Dane implies that Danes are 41 times more likely to bloat as mixed-breed dogs. The breed risk comparisons are based on retrospectively collected data from an earlier Morris Animal Foundation-sponsored study of 1,934 dogs with bloat and 3,868 without bloat (LT Glickman et al.: J. Amer. Vet. Med. Assoc. 104:1465-1471, 1994). Earlier comparisons based on these data included only the more common breeds. 

Breed  Number Enrolled Breed Risk of Bloat*
Great Dane 220 41.4
Irish Wolfhound 182
38.4
Bloodhound
128
25.6
Saint Bernard 127
21.8
Weimaraner 84
19.3


* Breed risk of bloat relative to risk in mixed-breed dogs, who are arbitrarily assigned a risk of 1.0. For example, weimaraners have 19 times the risk of bloat than mixed-breed dogs. 

There are no reliable population-based estimates of the incidence of gastric torsion in dogs. However, a large computerized multi-hospital record system, the Veterinary Medical Data Base (VMDB), indicates that the frequency of gastric torsion in dogs seen at veterinary teaching hospitals in the US has increased dramatically from 0.036% of all hospital admissions of dogs in 1964 to a peak of 0.57% in 1994, an increase of approximately 1500% (see Figure 1 below). This increase is unlikely to reflect changing diagnostic criteria or disease recognition. The increasing frequency of gastric torsion starting about 1969 affected most of the large and giant dog breeds. Therefore, it is also unlikely to be caused by genetic factors. However, this apparent epidemic of gastric torsion could be explained by introduction of one or more novel environmental factors such as a new ingredient in dry dog foods or a change in the manufacturing processes. It might also be related to changes in canine vaccines or their pattern of use, e.g. multivalent vaccines. Epidemiologic studies will be required to identify the causes of this bloat epidemic in the US and to monitor future trends. Keep in mind that despite appropriate veterinary medical care, approximately 25% of all dogs with gastric torsion will die of the disease.