Increasing hereditary health problems in the breeding of pedigree dogs on the example of Dobermans in Germany, in Europe and in the USA a comparative overview”
by Dr. Reinhard Haberzettl
Dr. Reinhard Haberzettl, born in 1952
1975 – graduation in biology study in the field of genetics
5 years in the pharmacological industry as a geneticist and toxicological scientist
from 1980 to 1990 – in the field of animal breeding research for agricultural animals
from 1991 again in the pharmacological industry
from 1970 (member of German association of Doberman breeders and occasional breeding attendant)
since 1994 additionally member of sport association and ardent breeder of German shepherd dogs
Short history about the health of the Doberman
The Doberman has been bred from different mixtures of various breeds and half-breeds at the end of the 19th century (Goller 1912, Dom 1957). This genetic variety (heterozygosity) was a great advantage for the health of the breed because up to approximately 1950, worldwide, there was practically no hereditary conditioned problems. The Doberman was vigorous and long-lived; these were qualities that still remained in the populations of East Germany and East Europe up to the nineties.
Between 1970 and 1990 the Doberman turned into a vogue breed in the USA which caused mass breeding. The causes of the Doberman’s boom were the growing need for security and the successful advertisement of the image of the breed in movies as a protector dog. This role was taken over by Rottweiler and German Shepherd dog in the nineties in the USA. As a result of the mass breeding of Dobermans, with a strikingly strong inbreeding factor and with insufficient attention to the breed’s hereditary health, the North American Doberman population has become extremely burdened with 6 hereditary defects (Table 1). Therefore we have to speak of a strong breed degeneration that might be almost irreparable with any means of animal breeding. The population of German and European dogs is similarly burdened with 2 hereditary defects in many breeding patterns in the USA. The other 4 hereditary defects are even scarcer but an increase is recognizable! For friends of dogs and genetic scientists it is a completely incomprehensible fact that until today, neither restriction of inbreeding nor a consistent breeding exclusion in genotype and in phenotype of burdened dogs, has taken place by breeding authorities in almost all European countries (in Germany as well) and on other continents.
Breeding of pedigree dogs and good health – utopia or a reachable goal?
Let me elaborate on some short, critical, constructive thoughts of mine about an essentially higher health rate in the whole breeding of pedigree dogs for the future because it concerns almost all breeds. Well-known veterinarians, genetic scientists, breeders and experts in animal protection increasingly criticize the quality of breeding control on the part of pedigreed dog organizations where health is not respected. One insistently demands that health as a breeding goal must be regarded just as highly as beauty and character. This demand should be implicit for all breeds in the future! The criticism of insufficient health care I summarize as follows:
- The beauty breeding may not burden the health as a result of too extreme an interpretation of the standard on the exhibitors part and in the practice breeding, but the breed standard must benefit the health (1998).
- Hereditary defects may be no more tolerated by beauty breeding but they must be quickly antagonized. Veterinary medical and animal breeding genetic institutes of universities therefore offer competent assistance. Breeding authorities, breeding judges, breeding attendants and breeders are not only responsible for beauty and characteristics of their pedigree dogs, but every one of them must take responsible-minded countermeasures against health dysgenesis regardless of temporary financial and prestige losses.
- Many breeding authorities (not all of them) used the offers of universities for assistance toantagonize hereditary defects insufficiently or made no use of them ast all in the past (Eichelberg 1998). This cooperation is logistically expensive and it requires higher demands on the responsible persons. It also requires honesty, a sense of responsibility and a readiness to educate oneself constantly!
Table 1 Estimated spread of seven degenerative hereditary diseases as well as their heredity (estimated value of genetic variance in the total variance) and their hereditary symptoms in different Doberman populations. The estimation of East European populations is also partly queried because an increasing extrusion of an indigenous gene pool takes place due to imports from Western Europe and from the USA and because there are barely sources.
|Spread of hereditary defects in:|
|Disease Symptoms||Heredity||Hereditary Symptom||USA||Western Europe||Eastern Europe|
|1. Sudden death by heart||middle||polygenetic?||very||high in some||little?|
|failure (cardiomyopathy)||until high||autosomally||high||lines|
|3. Thyroid glands||very high||several genes?||very||little?||little?|
|4. Hemophilia (Von-||very high||autosomally||high||little?||little|
|Willebrand disease = VWD||incompletely dominant|
|5. Wobbler syndrome||very high||monogene?||high||little?||little|
|6. Impaired visions until||high||autosomally||high||little?||little|
|7. Hip joint dysplasia (HD)||middle||polygene||little||little||little|
- The role of an uncontrolled inbreedinq should be restricted strongly in all breeds because it has led to an accumulation of defective genes. In breeding patterns burdened by hereditary defects we must either completely waive inbreeding or all breeding animals with external and hereditary degeneration should be excluded from breeding.
Fig. I Pedigree for heredity of heart muscle disease (cardiomyopathy, type B) from an American breeding pattern according to Calvert and Pickus (1989) over four generations. Grandfather, son and grandson fell ill and each of them was mated with healthy bitches. The grandson begot a litter of 5 whelps, 4 (3,1) of those fell ill.
In this article I am going to confine myself to the points of criticism No. 2 and 3 on the example of the Doberman. The insufficient attention to all 4 points of criticism in many breeds caused an unnecessary image decrease on the whole of pedigreed dog breeding in the public’s eyes in the last years. More self-criticism and more sense of responsibility towards the breed as well as towards the puppy buyers is necessary here, both on the breeder’s level and on the level of chosen breeding authorities. If the persons responsible for the health burdened breeds do not quickly succeed to reach the limitation of damage then we will have a similar development in Germany and in Europe as has been observed in the USA for approximately 10 years (Gunter 1996). The figures in the records of almost all breeds drop here continuously – it is extremely stark for the Doberman – because more and more dog fans prefer to pick up a dog from the SPCA or to purchase a healthier crossbred dog. The same situation occured in Germany in 2002.
The individual breeds and part populations of a breed can be heavily burdened with hereditary defects nationally and internationally in very different ways. On the example of hip joint dysplasia (HD) it should be briefly illustrated. There are very heavy burdened breeds e.g. St. Bernard, Leonberger, German Shepherd Dog and others. However, the success in the fight against it is very different in regards to the commitment and consequences of breeders. The Hovawart represents a very special, positive example. Concerning the German shepherd dog, the success in the fight against HD is very different specifically from country to country (Willis 1994, Haberzettl 1998). In the countries where the negative HD inherited dogs can be identified in spite of an external impeccable hip (phenotype good, gene type bad) as a result of consequent descendant registration; they can be isolated from breeding and the resultant achievement is that the frequency of HD strongly decreases. But, at the SV they were unsuccessful. For example the Airedale Terrier and the Doberman have a very low HD burden. Almost 100 percent of greyhound breeds and all wild dogs (e.g. the wolf) are HD free. In the worldwide view the Doberman has a relatively healthy hip. Since the beginning of X-Ray examinations 30 years ago in Germany the number of normal hips has lain almost constantly at over 90 percent. The breeding influence caused neither the deterioration nor the improvement. However, Table 1 shows where the hereditary conditional breed health problems lay and it illustrates 6 further deceasing characteristics that will be briefly presented in comparison to other breeds in the following text.
1st feature : Sudden death by heart failure (cardiomyopathy)
Many dog breeds are affected at various frequencies but in the death-rate statistics of all breeds the Doberman by far takes the sad first place in both the USA and in Germany. Mr. Kraft (1989), from the University of Munich, presents heart death statistics from dissection materials of different pathological institutes where frequently the Doberman stands before the Great Dane, the St. Bernard and the German Shepherd Dog. Beyond it Mr. Kraft presents the result of a regional survey of the Doberman Club (VDH) from South Germany. From 92 cases of deaths, 24 died of death by heart failure. The extensive statistics of death by heart failure in pedigreed dogs, by Calvert and Pickus (1982, 1989) from the USA, look like the situation in Germany. The Doberman by far leads the Great Dane, the Irish Wolf hound and the St. Bernard.
|The brown Doberman bitch Freya Vom Kohnstein SchHI WZ 6/44 biting while stopping the helper from fleeing in 1975 in two fleeing phases. The rapid quickness and the temperament of good skilled Dobermans must be considered at the helper activities.|
The majority of affected Dobermans die at the age 3 to 5 (van der Zwan 1987). Both in North America and in Europe there is an increasing reduction of the death age (Kollenberg 1998). In general, two progressive forms can be distinguished in the Doberman, dependant on the quickness of death and o
n other features (van der Zwan 1987, Schuler 1997). Type A: arrhythmia. With this most frequent type of death by heart failure the death occurs allegedly without (2?) external warning. All of a sudden the dog collapses and dies. There were few publications about the diagnosis of the dog’s arrhythmia but in the long-term ECG it should be similar to that of a human being. Type B: heart muscle weakness. With this less frequent type of death by heart failure a lingering development for a prolonged period is diagnosed. The dog often coughs in the morning as a result of water accumulation in the lungs. Diagnostically, heart enlargements and vessel changes can be located long before the death occurs.
An elegant black male dog, strongly inbred from oversized German breedings, death by heart failure. (Father: Jason von Nymphenburg)
A partly X-chromosome polygenetic hereditary transmission can be assumed because, according to the statistics, approximately 3/4 of all Dobermans that died of heart failure, are males. The noticeable frequency of death cases over several generations (Fig. 1) can be identified in the German and American Dobermans’ pedigrees. The heredity of sudden death by heart failure must be assessed as average to high. A complicated polygenetic hereditary process could exist because the symptom of death by heart failure is based on different heart defects and proceeding on the assumption that these defects were affected by certain environmental impacts. The cooperation between breeding clubs and genetic scientists is necessary for a better understanding of genetics. Calvert and Pickus recommend that the clubs utilize as many breeding animals as possible, along with their descendants, to take a standardized heart examination. A combination of several methods is useful, like for example, a long term ECG for diagnosis of function changes and fan ultrasound test for size recognition identification and x-ray.
2nd feature: Volvulus
Volvulus appears in many of the bigger breeds with different frequency. It is a life threatening disease and it has to be urgently veterinary treated if the dog should survive. According to Willis (1994) the German Shepherd Dog, the Berner Sennen Dog and the Doberman are among the most frequently affected in Europe. In the USA, according to death case statistics over 26 breeds (Schuler 1997), the German Dog, the St. Bernard and the Weimaraner are especially heavy affected. In breed comparisons the Doberman is only in the 8th place here but with a strongly increasing tendency. From 1964 until 1994 the clinical admissions of this breed dramatically increased by 1500% ! Of all 92 registered death cases of Dobermans in South Germany, 15 (16%) died at volvulus. In Germany many Dobermans were even successfully operated on twice during their lifetime and then they were used for breeding. An increase of volvulus within definite breeding patterns is noticeable – the genetic basic is clear, but environmental factors play a role as well. The hereditary symptom is not yet exactly known. Because of the fact that volvulus was affected by certain environmental impacts (e.g. filling quantity in stomach, movement or rest after the meals, anatomical special features of the form of rib cage and rib width and others), a polygenetic hereditary symptom can be assumed. At the moment the heredity can be judged as a method.
3rd feature : hypofunction of thyroid gland (hypothyroidism)
Besides the Doberman, the Husky, Malamute, Labrador and Beagle are also burdened with this hereditary defect (Willis 1994). After Jean Dodds study (1988), over 60% of Dobermans in the USA had hypofunction of the thyroid gland. It is similar to that a human being in that if it is untreated it can also lead to various and partly unspecific disease symptoms in dogs; for example, hair and skin illnesses, muscle and nervous diseases, loss of weight, digestive troubles, infections and other symptoms. Quality of life and life expectancy have been reduced heavily without hormone treatment. It is comparatively easy to diagnose and easy to treat by daily giving hormones in the form of pills therefore there are pleasant benefits for diseased Dobermans. However, if breeding is being pursued with these hereditary diseased dogs, as it is normal in the USA, then the breed is existentially endangered. Hypothyroidism can strengthen the symptoms of other diseases once more: cardiomyopathy, VWD and Wobbler’s syndrome. The high heredity of thyroid gland hypofunction is estimated at 90% (Jean Dodds 1988). Therefore the environmental impact is only small (with the exception of hormone substitution!). A mutation of one or only few genes can be assumed.
4th feature: hemophilia (von Willebrand’s disease (= VWD-bleeder)
“Von Willebrand’s disease” is a very special blood coagulation disorder that can be transmitted autosomally and is incompletely dominant (Schuler 1997). The homozygote (pure hereditary) bleeders are lethal, the heterozygote (mixed hereditary) bleeders are viable. External and internal bleedings, that could last very long with this hemophiliac type, can occur any time and must be treated by a veterinarian! No other breed of dog is so strongly affected by this hemophiliac disease in the USA like the Doberman. Occasionally cases were described for Corgis, Shelties, German Shepherd Dogs and Golden Retrievers (Willis 1994). The Doberman breeders in the USA reacted far to slowly to this disease that has a very high heredity. That shows in the speed that it spread: in 1977 55% of Dobermans were hemophiliacs, in 1984 61% percent were, in 1987 70% percent were and in 1990 the hemophiliac number had increased to 75%. Further increase can be expected because the breed authorities have taken extremely low action against limiting the damage. Probably the European Doberman is still the lowest burdened with hemophiliac defects at the moment but exact figures do not exist. Since 1970 the US hemophiliac breeding animals have been interbred slowly but increasingly in the Netherlands, Italy, Norway, Hungary and in Germany – its almost inconspicuous, even for insider breeders – the European population must be checked most urgently. The extensive North American experiences can be very helpful here.
A robust brown male dog from Russian breeding, a very powerful type without inbreeding and without West European ancestors
5th feature: Wobbler’s syndrome (paralysis)
Wobbler’s syndrome is a hereditary, degenerative disease of the neck spinal column, mostly in middle age. Deformed intervertebral discs and spine bodies press so strongly on the parts of nerve tissues in the spinal cord that pain, movement disorders and paralysis occur. Therapy without surgery holds little promise of success. Besides the Doberman, such cases took place in the German Dog, Basset and Borzoi. In comparison with Europe the Doberman should be more burdened in the USA, according to Schuler (1997). However, exact figures are neither known for North America nor for Europe. The exact heredity is not clear because the cooperation of the breed clubs with the Universities is far too small. Van der Zwan (1987) supposes a probable high polygenetic heredity.
Two Doberman bitches during the attack (on left – Anka Von der Domstadt, SchHI wz 6/34 and on right Tendy von Schrotturm, SchH III)
6th feature: Deqenerative eve diseases (PHTVL, PHPV)
Impaired visions up to the full loss of sight as a result of a genetic conditioned degeneration in the eye occur in many breeds differently and frequently. According to Willis (1994) the Staffordshire Bull Terrier, Basenji and the Doberman are affected most strongly. A disorder of the fetal development of the eye results in little and big spots as well as turbidity on the eye; the spots are caused by persistent (they do not disappear) embryonic membranes and blood vessels.
It is assumed to be an autosomal incompletely dominant heredity symptom (Schuler 1997) and a high heredity should be expected. Over 40% of the examined Dobermans in the USA have been affected by the disease and their eye sight was restricted; only 3% of the dogs however were badly affected. It is assumed that this disease spreads rarely in Europe in the Doberman but further details are not known. The abbreviated feature of PHTVL means: persistent hyper-plastic Tunica vascularis lentis and of PHPV means: persistent hyper-plastic primary Vitreum.
Conclusions for all breeds
Through the negative example of the Doberman in the USA and partly in Germany, the reader can understand that in less than 20 years the Doberman developed from a very healthy, vital and long-lived breed to a breed that is susceptible to disease with an average life-expectancy of under 7 years. The genetic degeneration of the whole population in the USA has progressed so far as a result of the breeding with ill animals (phenotype and genotype) as well as due to inbreeding so that the middle life-expectancy of over 5 years can be reached for every individual dog with great financial and veterinarian expenditures only (e.g. – 1 pill of thyroid gland hormone daily, heart drugs, blood coagulation compounds and others)! In general the following rule applies to all breeds with frequent health problems: veterinarian medical measures (diagnostics and therapy) are not enough for breeding animals. The gene pool of the whole breeding population must be improved by means of intelligent animal breeding and genetic breeding strategies; i.e. by special selection. The following veterinarian and animal breeding measures should be achieved together:
- Specifically to a breed, all breeding animals could provide a certificate of standardized examination of University clinics concerning all problem features of the breed (e.g. – 6 features for the Doberman in Table 1) in the future, in order to enable breeders to select and identify diseased breeding animals (phenotype) and hereditarily burdened animals (genotype). This certificate could also be used for the close connection between breeding, health and exhibition.
- The carrying out of these examinations requires dedicated, logistical preparations and arrangements between breeding authorities and universities, but the first step must always come from the breeding authorities.
- Inbreedinq and pattern breeding (wide inbreeding) with breeding animals from the patterns with increased health risk (e. g. – death by heart failure and volvulus in the Doberman) are to stop in the future. Instead, the breeding authorities could develop intelligent, external breeding strategies for their members, where health tested breeding animals would be the first consideration.
The VDH should nationally and the FCI should internationally write health as the 1st breeding goal of the pedigreed dog on their flags as they did before. For instance, by the reform of exhibitioning (Herzog 1998), the holding organizations of pedigreed dog breeding could, in a certain way ‘from above’, favor exhibition dogs and breeding dogs with health certificates during the awarding of winner’s titles and during placing of the dogs. In this manner health, as a breeding goal, could be considerably promoted. Innovative, combatative strategies against hereditary diseases, specifically breed – promoted, required and controlled by VDH and FCI, could improve the shaken reputation of pedigreed dog breeding to the public, first and foremost being the benefit of our dogs.
Mr. Bernd Przadka with the Doberman bitch Tendy vom Schrottumi during the subordination
- Caivert, C.A. and. Pickus, C.W. (1982), “Cardiomyopathy in the Doberman Pinscher Dog”, Doberman World.
- Caivert, C.A. and. Pickus, C.W. (1982), “Cardiomyopathy in the Doberman”, Our Doberman 11/1989
- Dodds, J. (1988) in Solan, P., “Hereditary health problems”, Doberman Quar
terly, Fall 1988.
- Dorn, K. (1957), “Dog and environment”, Berlin.
- Eichelberg, H. (1998), “Support of science to breeding societies”, Our pedigree dog, 1/1998
- Goller, O. (1912), ,The Doberman pinscher in word and picture”, Apolda.
- Gunter, B. (1996), “Dog Shows in den USA”, The dog 4/1996.
- Haberzett., R. (1990) in Schiller, G., ,The Doberman”, Urania and Kynos 1990.
- Herzog, A. (1998) “Current problems in the pedigree dog breeding”, The dog 7/98
- Kollenberg, A. and J. (1998), Personal message.
- Kraft, H. (1989), University Munich, “Heart disease and volvulus at the Doberman”, Our Doberman 10/1989
- Schuler, G. (1997) ,The great Doberman book”, Kynos
- Schuler, G. (1997) “Causes of dog volvulus”, Our Doberman 12/1997.
- Sretzky u. Trautvetter (1993), FU Berlin, Personal message
- Our Doberman, Age groups 1921 till 1998
- van der Zwan, M. (1987), “A hundred Doberman dogs”
- van der Zwan, M. (1988), “A hundred Doberman bitches”
- Willis, M.B. (1984) “Breeding of dog”, Ulmer.
- Willis, M.B. (1992), “Genetics of dog breeding”, Kynos
Conclusions to the breeding of a healthy Doberman in Europe as well as word
wide for the purpose of rescuing the breed from extinction as a result of
threatening degeneration (strategy with 4 breeding measures)
While in North America the great hereditary health problems were analyzed and corrected in 6 features, inoffensively and honestly. Most breeding authorities in Europe take the helpless view, with their breeders and in public, that there should be few or no health problems at all. There is an irresponsible attitude, for instance, towards uninformed purchasers of puppies, who are very disappointed if their still young dog falls ill with or dies of cardiomyopathy or volvulus. The other 4 hereditary diseases described appear in Europe more often because of the high inbreeding and unsatisfactory health tests of most breeding animals and they cause highly increasing costs at the veterinarian and for medication. Due to this fact the life quality of the dogs (and owners!!!) deteriorates and thereby shortens the life expectance of many dogs by years!
Immediate inbreeding interdiction for the Doberman in Europe, North America and worldwide.
Inbreeding of diseased hereditary defected breeding animals magnifies the frequency and the severity code of all diseases – it is a truism. A genetic, suggestive boarder of maximal kinship between 2 parents must be determined,because there are flowing transitions between external breeding and breeding. Suggestion : maximal 3-3, i.e. – for example both parents have a common grandfather. The puppies then have an inbreeding coefficient F (= inbreeding degree) of 3,125 – i.e. – 3,125 percent of all genes are homozygous by inbreeding. According to Wright (1922) this mathematical and statistical standard method is used in the whole animal breeding for calculating the increase of homozygosity by common ancestry (Willis 1984) and it can quickly be calculated per pocket calculator or computer. According to the definition of Haberzettl (1990), the coefficient F of external breeding is under 3 percent in dog breeding, over 10 percent in close inbreeding (incest) and in the field of 3 to 10 percent where we speak about wide inbreeding (= pattern breeding). The dogs whose parents are half siblings, have the coefficient F of 12,5 percent, i.e. – 12,5 percent of all genes are homozygous. This method is described in all good books about dog and animal breeding. If breeders and breeding authorities of the Doberman continue to pursue inbreeding using ill, hereditarily defected and not health tested (without certificate for being free of 6 hereditary defects) breeding animals (F over 3 percent or also external breeding (F under 3 percent), then they must put up with the reproachable “distress breeding” of diseased animals. Besides, unpleasant legal consequences caused by puppy purchasers, the breed would have no medium-term survival chance because, for a short-period, only foolish purchasers would want to buy a Doberman whose life expectancy was shortened and whose life support is possible only with extremely high veterinarian and medication expenditures.
The gene reserve breeding (according to the model of rescuing the extinction of endangered wild animals and the old valuable domestic animal breeds) with healthy (i.e. – health tested for 6 hereditarily detected features) breeding animals from Eastern Europe, which have no western European or North American ancestors. The close relatives (parents and siblings) should be very long-lived and they should show the diseases as little as possible in the middle and higher age (low morbidity)! These gene reserve Dobermans could be later combined with strictly health tested animals from normal breedings and they could form a new healthy basis for the breed.
As after 1990 most Russian and East German breeders immediately exchanged their healthy, but not so elegant breeding material for western European breeding animals in order to be able to compete in the exhibitions, the valuable gene pool of old robust long-lived and very healthy breeding pattern fell almost to 0 in 2002.
Worldwide cooperation of the Doberman Clubs while fighting against the degeneration due to hereditary diseases.
In close cooperation between the European and the North American Clubs (as until 1939) as well as with university clinics of both continents, joint data banks encompassing health tests of all breeding animals should be set up as well as international genetic and veterinarian-medical studies should be carried out for example with the following questions:
- with which frequency have the 6 (and possibly even others) hereditary defects in the populations existed?
- which hereditary symptoms do exist?
The more thorough and honest the analysis and diagnosis are, the more effective further breeding measures can be for rescuing the breed.
Crossbreeding of other healthy breeds as a method for selection and as the last emergency measure against the final degeneration of the Doberman.
Insofar as the measures 1 to 3 should not be realized for different reasons (irresponsibility, indifference, egotism and others), only crossbreeding remains. Therefore measure No. 2 could also be cancelled because the last healthy Dobermans of the old patterns became extinct as a result of the prestige-pregnant extrusion breeding between West European and US-blood European Dobermans. For example, in the seventies the breeding has been re-bred in Hungary with a number of US-blood “Doberhill” – Dobermans from Norway. The Hungarian breeders, as good businessmen, have sold
their dogs to all eastern European countries. Keegan v. Ferrolheim from Holland with his US-father “Pinemead’s Independence” has been a very popular breeding male dog in the eighties in the Italian kennels “del Littorio” and this dog has scattered a great number of descendants all over Europe. In the nineties the Dutch “Franckenhorst” kennels have interbred their former pure European top dogs with the US-line “Marienburg”. These US-blood “Frankenhorst Dobermans were strongly used all over Europe as breeding dogs. These are only some few examples.
The crossbreeding of another breeds as a breeding method may be less popular among dog breeders but it represents a frequently used standard method for most domestic animal breeds; e.g. – in horse breeding. In almost all warm blooded animals the performance and health tested elite studs of the breeds “English or Arabian Thoroughbred” are permanently interbred in dependence on this breeding strategy. For the Doberman it is thinkable to use the Beauceron, the German Shepherd Dog or other Shepherd Dog breeds, the Weimaraner or other Short-haired Pointers.