As a breed association, you can use a ZooEasy database to store all information about your breed in one place. This includes details on pedigrees, health, show and working results, as well as inbreeding and kinship, for example.
Inbreeding coefficient
It has recently become possible for breed clubs to obtain these COIs at the DNA level. Van Haeringen Laboratory (VHL) tests the DNA of all Dutch pedigree dogs on behalf of the Raad van Beheer. The aim of this is to establish the parentage of newborn puppies. As part of this DNA testing, the COIs of these dogs are also determined. Breed clubs that are members of the Raad van Beheer can enter into an agreement with the Raad and VHL to receive these figures. And, of course, this data can then be recorded in the club’s ZooEasy database.
Using ZooEasy, you can easily calculate the inbreeding coefficient (COI) of a dog or future puppy. These calculations are performed based on the pedigree data available in the database. However, it is now also possible to have a COI determined based on DNA testing. This gives you an even clearer picture.
DNA COIs of the NSDTRCN
The Nova Scotia Duck Tolling Retriever Club Nederland (NSDTRCN) has taken advantage of the above opportunity. Barbara and Esther from the NSDTRCN explain how this process went for them:
“In December 2024, we paid a visit to CombiBreed/VHL (CombiBreed is a brand of Van Haeringen Laboratorium, ed.). Prior to that visit, we had already heard from a board member of a friendly breed association that CombiBreed can calculate the COIs and heterozygosity (genetic diversity, ed.) of dogs. They do this using the DNA samples they receive for the DNA parentage verification they carry out for the Raad van Beheer.
During our visit to VHL, we enquired about this and received an explanation. As a board, we subsequently decided that we would like to receive this data. We wish to use this to provide our members with a clear and transparent picture of the state of our population.
Inbreeding and diversity
A healthy population is based on maintaining sufficient genetic diversity. That is why we aim for high heterozygosity, whilst at the same time seeking to control and keep the COI of offspring low. A low COI is important for minimising the negative effects of inbreeding as much as possible. A higher level of genetic diversity ensures, for example, that a dog has a well-functioning immune system. COI and heterozygosity are interrelated; the higher the COI, the lower the heterozygosity. And the lower the heterozygosity, the higher the COI.
Dogs that themselves have a high COI can still produce offspring with a low COI and high diversity. Inbreeding itself is not hereditary; what matters is how closely related the male and female are. If both the male and female have a low COI but are related to each other, the puppies will have a higher COI. Conversely, if the male and/or female have a high COI, they can still produce puppies with a low COI when bred together. Provided, of course, that the male and female are not related to each other. By using COI and heterozygosity values, we can gain a better understanding of how our breeding policy works in practice. This allows us to see whether we are indeed seeing the COI decrease and heterozygosity increase.
To be received before Christmas
Once we had decided that we would like to have the data, we set the process in motion. This went extremely well and very smoothly. Following our visit to VHL, we sent an email to the Raad van Beheer. Within three days of our visit to VHL, we had received the agreement from the Raad, signed it, and sent it back. We received the invoice for the data via VHL, and we had already received the COIs and heterozygosity values before Christmas.
We received the information as a large Excel file containing the values for over 1,500 dogs. To process the data properly, we wanted to import it into our ZooEasy database. To do this, following the example of a breed association we know, we created two additional fields in our ZooEasy database. We then contacted ZooEasy to ask if they could enter the data for us. That was no problem. We sent them the data, and for a small fee, our file was converted and imported into our database. By mid-March, all the data was in place.
A better understanding of the population
We hope this data will provide us with greater insight. High genetic diversity is beneficial for the breed as a whole. Low inbreeding is also beneficial. The relationship between the two is complex, and it is important to strike a balance between genetic diversity and inbreeding. As a breed association, we believe it is important to understand this for the sake of our population.
For now, our ZooEasy database is only accessible to our volunteers. However, once we go live with ZooEasy and our breeding members have an account, they will also be able to view the COIs from VHL. This is useful for breeders as it allows them to gain a better understanding of their breeding programme. They can thus get an idea of how their bred puppies score in terms of inbreeding and diversity.
Unfortunately, the COIs from VHL and Embark are not comparable. This is because these two laboratories both use a slightly different DNA profile and a different method of calculation. However, as VHL obtains the DNA profiles for parentage verification via the Raad van Beheer, this COI will become visible for an increasing number of Tollers in the future.
A valuable collection of all Tollers
We found the whole process to be a positive experience. From consulting with fellow breed associations to visiting CombiBreed/VHL, handling the administrative aspects via the Raad van Beheer, and finally obtaining the COI and heterozygosity calculations and importing them into ZooEasy. The process went smoothly and we were able to enter all the data clearly in one place.
We have now received the data for all Dutch Tollers, from November 2021 up to and including approximately October 2024. However, we would also like to continue receiving data on Tollers born since then and keep adding them to ZooEasy. Apart from their usefulness to breeders, these COIs provide an overview of the entire population, of the total number of NSDTRs bred in the Netherlands for which a pedigree has been requested. That is extremely valuable to us as a breed association.”