February 2023

Dear fellow Schapendoes breed clubs and breeding committees,

Recently, the Vereniging de Nederlandse Schapendoes was approached by professor Giorgia Santarelli, cardiologist at Utrecht University (the only vet school in the Netherlands) about starting a study in Schapendoezen concerning heart disease and especially PDA, Patent Ductus Arteriosus.

“Patent ductus arteriosus (PDA) is the most common congenital heart disease in dogs. It is due to the failure of the ductus arteriosus muscle to constrict, leaving a passageway for blood flow and resulting in eventual left-sided heart disease and/or generalized heart failure. It is hereditary in several breeds.”
In the past years we occasionally had cases of PDA, recently one which was discovered very late (at 1.5 years, the dog did not survive unfortunately). Breeders have the option to have surgery for affected puppies or to euthanise them. Early-age surgery is usually very effective but also quite costly.

Utrecht University is interested in improving the standard puppy/litter check of veterinarians, creating new protocols on how heart ultrasound scans have to be performed and training the new vet students better. They are also interested in DNA research and possibly develop a DNA test for Schapendoezen regarding PDA.

The basis of Utrecht’s question is: where does it go wrong? Why do vets sometimes pick up a PDA too late. Why is the choice possibly made to ‘wait’ and see if the dog grows over a heart murmur? Is there something wrong in the training of our vets? Is the diagnosis or equipment not good enough? A heart murmur can normally be easily heard and a PDA sounds very distinctive: loud and specific. As soon as a heart murmur is detected that is (possibly) a PDA, an ultrasound should always follow as far as professor Santarelli is concerned.

-Utrecht has new state of the art scanning equipment that needs to be properly calibrated for Schapendoezen.
-Based on this new equipment, a new protocol for vet education (incl. refresher training of existing vets) will be developed by Utrecht University and implemented in vet education. How should a vet perform an ultrasound and interpret results of a heart examination.
Utrecht University already obtains data (blood/DNA and ultrasound data, possibly surgery reports) of 11 PDA sufferers that were treated at the University in recent years, Dutch dogs. But of course other hospitals in the Netherlands perform heart surgery too. More blood/DNA is needed from all living PDA affected dogs. Utrecht would like to keep track of PDA affected dogs for a number of years, to study the development of disease and treatment results.
We would like to ask you to provide us with details on PDA cases you may have had in recent years. We have been able to find written data in Doesdata obviously, but it’s not always clear what the exact issue was or who owns a dog. We may also miss some relevant information still. Would it be possible to provide us with contact details of breeders and/or owners you are aware of that had PDA in their litters? If it’s not possible to provide it to us but you do have records, would you be willing to inform the people concerned about this new study and ask them to contact us? Of course if you have no knowledge of PDA in your country, we would also like to hear that.

We would require medical records and if possible, blood samples. Obviously, if people are willing to participate in study days in Utrecht for ultra sounds, they would be very welcome but we are aware that logistically this might be a big challenge and not feasible. But we want to try to conduct a thorough study including data of the whole population and not make this a national or VNS-only project, if possible. Eleven cases currently are still too few to start a study to heredity: the more DNA we could collect the quicker developments in the study can go. If a DNA test can be developed in the future, we can avoid occasionally breeding PDA affected dogs, which would mean a lot to breeders and in some cases also to pup owners. We will hopefully improve the health of our breed.

For Dutch dogs, we will soon start a collaboration with the Utrecht University:
-Litters from 6 weeks old can be examined in Utrecht by the professor and her team, instead of at a regular vet.
-We will collect all data of affected Dutch Schapendoezen that is missing in Utrecht and supply it. Those affected in the past and are still alive but have no data in Utrecht, will be invited for an ultrasound scan and blood sampling. Ms Santarelli is discussing with geneticists whether blood is only needed from affected individuals or possibly also from parents and littermates.
-Prof. Tosso Leeb of Bern University in Switzerland has done heart studies on Schapendoezen in the past. Utrecht is in touch with him for exchange of data.
-In addition, we need to build a reference group of healthy Schapendoezen. What are the standard ultrasound findings/values/results in healthy dogs aged 1-6 years. Utrecht offers them a free ultrasound in their study. They also need to donate blood to further build up a DNA bank for comparison and research. To arrange this we will preferably organise special days in 2023 for people willing to participate in this. Possibly a gPRA test for breeders or stud-dog owners could be combined with blood donation, for example.
-We are currently investigation all options for sponsoring to make sure we keep costs to a minimum for participants. We have funds for research at the VNS and we also have Stichting Schapendoes 1947 which is dedicated to funding scientific research. It is in the interest of our breed to get as much DNA information as possible, not only for this but in general, and not only of breeding dogs but all dogs. We can certainly discuss how to handle costs for blood sampling and shipping it to Utrecht, in case breeders/owners from your country are interested in contributing to this study.
For now, our main question is: do you have recent cases of PDA in your country/club and would it be possible to provide us with contact details of breeders/owners, or are you willing to reach out to them for us? We would love to hear from you so we can have a clear view on what can possibly be provided to the professor for her study.

If you have any questions, please do not hesitate to contact us. We are currently working with the professor on an article that can be published in our magazine and on the website, to explain everything to breeders and owners. We will make sure it gets translated and send to you as well. As soon as we have more information on procedures, costs etc. we will inform you. But for now, thanks in advance for letting us know if you can assist us with collecting contact information.

Best regards,

Committee for Population Management – Vereniging de Nederlandse Schapendoes
Carlian Brauckmann, Miranda Nijland, Marjolein Flobbe

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