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by Kaffirdog on 16 February 2010 - 14:02
I'm not slaughtering any test Simon and can't see where you think I am. Highly reliable is not 100%, but clearly better than nothing and I'm surprised it has not been publicised before if it is so freely available and reliable.
Margaret N-J
Margaret N-J
by 1doggie2 on 16 February 2010 - 17:02
I find the health of the GSD by breeders is more like the "underground papers" you learn about the defects of the dogs thru rumors and then watch the litters to learn if the rumors have any teeth. I did a lot of research on the dwarfs, because I received 2 of them from the same sire and different dams. Common sense tells you to breed away from health/faults and breed into strengths of the dogs. There are some dogs that just do not produce well to most bitchs or the correct one is not being used, he is what I call a needle in a haystack stud and should be taken out of the gene pool, not just because they produce soft ears, you can breed around that. However, to breed around the issues, you need to know what they are and who is a carrier. If you are willing to breed into the health problems then as a breeder you should be willing to keep those pups which have the issues and foot the medical bills yourself.
by Superdog on 16 February 2010 - 17:02
There is someone present in this country who was working with Utrek who studied Dwarfs and who had collected much info on this.
John Walker.
The other person with vast knowledge on the subject is A lady whom Kaffidog knows. Like Katrina her knwledge is vast.
John Walker.
The other person with vast knowledge on the subject is A lady whom Kaffidog knows. Like Katrina her knwledge is vast.
by Mark3 on 16 February 2010 - 22:02
Some info here on John Walker's website www.accdata.co.uk/dwarfism/index.html There are some Dwarf pedigrees on here for those that haven’t seen them.
This is an extract of an article written by John Walker in 1992; obviously things have moved on since then and a test is now available but it is food for thought. www.accdata.co.uk/dwarfism/article1.html
The Genetics and Possible Health Issues
'Assuming that the autosomal recessive theory with a possible gene dosage effect is correct, then this means that the normal state is dominant and that two affected animals must be mated in order to produce a dwarf puppy. It also means that heterozygotes (carriers of the defective gene) appear to be perfectly normal, fully grown animals. Herein lies part of the problem.
It is therefore possible to mate a carrier dog or bitch to a normal partner ad infinitum without producing a dwarf puppy or seeing any other problem which one might associate immediately with 'dwarfism'. Many breeders will be doing this unwittingly as I have done. This in turn produces a further 50% of carriers and only 50% normal animals. In this way a pool of defective genotypes with apparently normal phenotypes is being created unseen.
When two carriers are mated the situation gets worse. In theory (remember these figures only apply to large populations and not necessarily to individual litters of puppies) then the ratio of carriers produced remains the same at 50% but the ratio of normal animals produced falls to only 25% with the other 25% being 'scrap' as dwarfs and dead puppies. This is the normal Mendelian 1:2:1 ratio and the Danish, Australian, and my own ratios agree fairly well with the prediction. In this case 2/3 (67%) of the survivors are defective genotypes; but they all look normal.
The other side of the problem lies in the evidence that the apparently normal looking carriers may, in fact, have abnormal hormone balances. They may not be normal fully functioning animals but animals which function under physiological/biochemical stress. In consequence these animals be less viable than truly normal animals and will show tendencies arising from physiological stress; typically a predisposition for infection, deficiency diseases, and reduced fertility and libido as well as possible character and temperament problems, which we can all do without. In other words, they may well be costing more than average in veterinary services'.
This is an extract of an article written by John Walker in 1992; obviously things have moved on since then and a test is now available but it is food for thought. www.accdata.co.uk/dwarfism/article1.html
The Genetics and Possible Health Issues
'Assuming that the autosomal recessive theory with a possible gene dosage effect is correct, then this means that the normal state is dominant and that two affected animals must be mated in order to produce a dwarf puppy. It also means that heterozygotes (carriers of the defective gene) appear to be perfectly normal, fully grown animals. Herein lies part of the problem.
It is therefore possible to mate a carrier dog or bitch to a normal partner ad infinitum without producing a dwarf puppy or seeing any other problem which one might associate immediately with 'dwarfism'. Many breeders will be doing this unwittingly as I have done. This in turn produces a further 50% of carriers and only 50% normal animals. In this way a pool of defective genotypes with apparently normal phenotypes is being created unseen.
When two carriers are mated the situation gets worse. In theory (remember these figures only apply to large populations and not necessarily to individual litters of puppies) then the ratio of carriers produced remains the same at 50% but the ratio of normal animals produced falls to only 25% with the other 25% being 'scrap' as dwarfs and dead puppies. This is the normal Mendelian 1:2:1 ratio and the Danish, Australian, and my own ratios agree fairly well with the prediction. In this case 2/3 (67%) of the survivors are defective genotypes; but they all look normal.
The other side of the problem lies in the evidence that the apparently normal looking carriers may, in fact, have abnormal hormone balances. They may not be normal fully functioning animals but animals which function under physiological/biochemical stress. In consequence these animals be less viable than truly normal animals and will show tendencies arising from physiological stress; typically a predisposition for infection, deficiency diseases, and reduced fertility and libido as well as possible character and temperament problems, which we can all do without. In other words, they may well be costing more than average in veterinary services'.
by Sue B on 16 February 2010 - 22:02
Excellent post Mark3. Thank You.
Regards
Sue b
Regards
Sue b
by hodie on 16 February 2010 - 23:02
I am posting the entire article here rather than on my web site. If you wish a copy of it, please email me at:
schwarzenberggsd@earthlink.net
The research has now been submitted to a very prestigious journal for publication consideration. In case you do not know how such a process works, it can take some time to gain approval from peers. I do not know how long this will take, but when the full study is published, I will have a copy of it and make that available to anyone who would like it. In the meantime, I also have the form for submission of blood samples for the test. If you would like to get a copy of that form, please also feel free to request it from me. I will post both the article and the form on my web site as soon as I have time.
Pituitary dwarfism in German shepherd dogs
-Availability of a genetic test-
Annemarie Voorbij and Hans Kooistra
Department of Clinical Sciences of Companion Animals
Faculty of Veterinary Medicine, Utrecht University
Utrecht, The Netherlands
The pituitary is a hormone producing gland at the base of the brain. This pea-sized gland is composed of three parts: the anterior pituitary, the intermediate lobe and the posterior pituitary. The anterior pituitary synthesizes and secretes six hormones, which are essential for numerous body functions, such as growth, reproduction, lactation, metabolism and handling stress. These 6 hormones are:
· Growth hormone (GH), which is essential for growth
· Thyroid stimulating hormone (TSH), which regulates thyroid function
· Prolactin (PRL), which is essential for lactation
· Follicle stimulating hormone (FSH) and Luteinizing hormone (LH), which are essential for ovulation in female animals and sperm production in male animals
· Adrenocorticotroph hormone (ACTH), which stimulates the adrenal cortex
schwarzenberggsd@earthlink.net
The research has now been submitted to a very prestigious journal for publication consideration. In case you do not know how such a process works, it can take some time to gain approval from peers. I do not know how long this will take, but when the full study is published, I will have a copy of it and make that available to anyone who would like it. In the meantime, I also have the form for submission of blood samples for the test. If you would like to get a copy of that form, please also feel free to request it from me. I will post both the article and the form on my web site as soon as I have time.
Pituitary dwarfism in German shepherd dogs
-Availability of a genetic test-
Annemarie Voorbij and Hans Kooistra
Department of Clinical Sciences of Companion Animals
Faculty of Veterinary Medicine, Utrecht University
Utrecht, The Netherlands
The pituitary is a hormone producing gland at the base of the brain. This pea-sized gland is composed of three parts: the anterior pituitary, the intermediate lobe and the posterior pituitary. The anterior pituitary synthesizes and secretes six hormones, which are essential for numerous body functions, such as growth, reproduction, lactation, metabolism and handling stress. These 6 hormones are:
· Growth hormone (GH), which is essential for growth
· Thyroid stimulating hormone (TSH), which regulates thyroid function
· Prolactin (PRL), which is essential for lactation
· Follicle stimulating hormone (FSH) and Luteinizing hormone (LH), which are essential for ovulation in female animals and sperm production in male animals
· Adrenocorticotroph hormone (ACTH), which stimulates the adrenal cortex
by hodie on 16 February 2010 - 23:02
Continued:
Any defect in the development of the pituitary gland may result in a form of isolated or combined pituitary hormone deficiency. In dogs, congenital GH deficiency or pituitary dwarfism is the most striking example of pituitary hormone deficiency. This recessive inherited disorder is encountered most often in German shepherd dogs, but it has, for example, also been reported in Saarloos wolfhounds. The genetic defect causing congenital GH deficiency in German shepherd dogs is also the cause of pituitary dwarfism in Saarloos wolfhounds, because the disorder in the latter breeds was first recognized after German shepherd dogs had been used in the breeding of Saarloos wolfhounds.
German shepherd dwarfs have a combined deficiency of GH, TSH, PRL, and the gonadotropins.
In contrast, ACTH secretion is preserved in these animals.
Dogs that are carriers of the mutated gene that causes pituitary dwarfism do not have any symptoms and look exactly the same as their fellow German shepherd dogs that aren’t carriers. Since pituitary dwarfism is a recessive disorder of a single gene, the birth of a dwarf indicates that both parents are carriers of the mutation.
Any defect in the development of the pituitary gland may result in a form of isolated or combined pituitary hormone deficiency. In dogs, congenital GH deficiency or pituitary dwarfism is the most striking example of pituitary hormone deficiency. This recessive inherited disorder is encountered most often in German shepherd dogs, but it has, for example, also been reported in Saarloos wolfhounds. The genetic defect causing congenital GH deficiency in German shepherd dogs is also the cause of pituitary dwarfism in Saarloos wolfhounds, because the disorder in the latter breeds was first recognized after German shepherd dogs had been used in the breeding of Saarloos wolfhounds.
German shepherd dwarfs have a combined deficiency of GH, TSH, PRL, and the gonadotropins.
In contrast, ACTH secretion is preserved in these animals.
Dogs that are carriers of the mutated gene that causes pituitary dwarfism do not have any symptoms and look exactly the same as their fellow German shepherd dogs that aren’t carriers. Since pituitary dwarfism is a recessive disorder of a single gene, the birth of a dwarf indicates that both parents are carriers of the mutation.
by hodie on 16 February 2010 - 23:02
Continued:
Pituitary dwarfs are significantly smaller than their healthy littermate, but the dwarfs are in proportion. Another clinical manifestation of pituitary dwarfism is that the dwarfs have retained their puppy hair coat. In time, the hair coat will be largely lost and the animal will become alopecic (bald) (Figure 1).
The growth retardation and the abnormal hair coat are mostly noticed by 2 to 3 months of age. The hairs are easily epilated, and when the animal loses its hair coat, the skin can become squameous and hyperpigmented, making the skin darker in color. Furthermore, due to a lowered local immunity of the skin, dwarfs are prone to bacterial skin infections.
However, the clinical signs are not limited to exterior appearances. The dwarfs suffer from a whole range of clinical manifestations far worse than skin and hair coat problems. For instance, GH deficiency also leads to underdevelopment of the kidneys, causing chronic renal failure. The deficiency of TSH will result in an underactive thyroid gland, causing the animals to be slow and dull. Furthermore, the insufficiency of the gonadotropins will result in failure of one or both testis to move, or "descend" into the scrotum (cryptorchidism) in male dwarfs. Female dwarfs do go into heat, but they do not ovulate. It can be concluded that pituitary dwarfism is a serious disorder.
Pituitary dwarfs are significantly smaller than their healthy littermate, but the dwarfs are in proportion. Another clinical manifestation of pituitary dwarfism is that the dwarfs have retained their puppy hair coat. In time, the hair coat will be largely lost and the animal will become alopecic (bald) (Figure 1).
The growth retardation and the abnormal hair coat are mostly noticed by 2 to 3 months of age. The hairs are easily epilated, and when the animal loses its hair coat, the skin can become squameous and hyperpigmented, making the skin darker in color. Furthermore, due to a lowered local immunity of the skin, dwarfs are prone to bacterial skin infections.
However, the clinical signs are not limited to exterior appearances. The dwarfs suffer from a whole range of clinical manifestations far worse than skin and hair coat problems. For instance, GH deficiency also leads to underdevelopment of the kidneys, causing chronic renal failure. The deficiency of TSH will result in an underactive thyroid gland, causing the animals to be slow and dull. Furthermore, the insufficiency of the gonadotropins will result in failure of one or both testis to move, or "descend" into the scrotum (cryptorchidism) in male dwarfs. Female dwarfs do go into heat, but they do not ovulate. It can be concluded that pituitary dwarfism is a serious disorder.
by hodie on 16 February 2010 - 23:02
Continued:
Although the physical features of pituitary dwarfism may seem obvious, the final diagnosis should be based on 'pituitary stimulation tests'. These tests can detect a deficiency of GH, TSH, prolactin, LH and FSH.
The most logical therapeutic option would be to treat the dwarfs with canine GH and thyroid hormone. Treating the animal with thyroid hormone is simple, but it is not possible to treat the dwarfs with canine GH, since it is not available for therapeutic use. However, research has demonstrated that porcine GH is identical to canine GH, making it a good alternative for treatment.
Without proper treatment, the long term prognosis is poor. Many dwarfs will not live more than 4 to 5 years. However, some dogs do live longer, probably because in some cases the pituitary still produces a small amount of hormones. Although the prognosis improves significantly when dwarfs are properly treated, their prognosis still remains guarded.
It should be clear that the birth of dogs with this serious illness should be prevented. In order to do so, two carriers of this mutation should not be bred. The problem is that, as mentioned earlier, one cannot distinguish a carrier from a non carrier judged on its appearance. This would require a genetic test. After 15 years of intensive research at the Department of Clinical Sciences of Companion Animals of Utrecht University, this test is now available! If this test would be used for all breeding animals, pituitary dwarfism could be completely eradicated in German shepherd dogs.
Although the physical features of pituitary dwarfism may seem obvious, the final diagnosis should be based on 'pituitary stimulation tests'. These tests can detect a deficiency of GH, TSH, prolactin, LH and FSH.
The most logical therapeutic option would be to treat the dwarfs with canine GH and thyroid hormone. Treating the animal with thyroid hormone is simple, but it is not possible to treat the dwarfs with canine GH, since it is not available for therapeutic use. However, research has demonstrated that porcine GH is identical to canine GH, making it a good alternative for treatment.
Without proper treatment, the long term prognosis is poor. Many dwarfs will not live more than 4 to 5 years. However, some dogs do live longer, probably because in some cases the pituitary still produces a small amount of hormones. Although the prognosis improves significantly when dwarfs are properly treated, their prognosis still remains guarded.
It should be clear that the birth of dogs with this serious illness should be prevented. In order to do so, two carriers of this mutation should not be bred. The problem is that, as mentioned earlier, one cannot distinguish a carrier from a non carrier judged on its appearance. This would require a genetic test. After 15 years of intensive research at the Department of Clinical Sciences of Companion Animals of Utrecht University, this test is now available! If this test would be used for all breeding animals, pituitary dwarfism could be completely eradicated in German shepherd dogs.
by hodie on 16 February 2010 - 23:02
Continued:
A genetic test may not seem to be of big importance to German shepherd dogs, since the disorder seems to occur only occasionally. However, one should keep in mind that many dwarfs die in the uterus or shortly after birth. One should also be aware of the fact that if just 1 percent of the German shepherd dog populations are dwarfs, then 18 percent of the population will be carriers of the mutation. This means that the number of carriers will be much higher than might be expected. When 2 of these carriers are mated, on average 25 percent of their offspring will be dwarfs and half of the siblings will be carriers of the mutation.
For the genetic test, 4 ml. of blood (collected in an EDTA containing tube) is needed. The blood sample has to be shipped to:
Dr. H.S. Kooistra (H.S.Kooistra@uu.nl)
Department of Clinical Sciences of Companion Animals
Faculty of Veterinary Medicine, Utrecht University
Yalelaan 108
3584 CM Utrecht
The Netherlands
The costs of the genetic screening for the mutation that causes pituitary dwarfism in German shepherd dogs are Euro 100 (excl. VAT).
In short, pituitary dwarfism is a serious, incurable illness of which the occurrence is highly underestimated! The good news is that there is now a genetic test with which carriers of the mutation can be identified. If all breeding animals were tested (only once), and a correct breeding policy would be implemented, this severe illness could be completely eradicated.
A genetic test may not seem to be of big importance to German shepherd dogs, since the disorder seems to occur only occasionally. However, one should keep in mind that many dwarfs die in the uterus or shortly after birth. One should also be aware of the fact that if just 1 percent of the German shepherd dog populations are dwarfs, then 18 percent of the population will be carriers of the mutation. This means that the number of carriers will be much higher than might be expected. When 2 of these carriers are mated, on average 25 percent of their offspring will be dwarfs and half of the siblings will be carriers of the mutation.
For the genetic test, 4 ml. of blood (collected in an EDTA containing tube) is needed. The blood sample has to be shipped to:
Dr. H.S. Kooistra (H.S.Kooistra@uu.nl)
Department of Clinical Sciences of Companion Animals
Faculty of Veterinary Medicine, Utrecht University
Yalelaan 108
3584 CM Utrecht
The Netherlands
The costs of the genetic screening for the mutation that causes pituitary dwarfism in German shepherd dogs are Euro 100 (excl. VAT).
In short, pituitary dwarfism is a serious, incurable illness of which the occurrence is highly underestimated! The good news is that there is now a genetic test with which carriers of the mutation can be identified. If all breeding animals were tested (only once), and a correct breeding policy would be implemented, this severe illness could be completely eradicated.
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