A heading dog being sampled for the project. Photo / Pam Stephen Photography
A heading dog being sampled for the project. Photo / Pam Stephen Photography
Early research in Massey University’s three-year project to better understand the genetic make-up of working farm dogs has yielded some surprising results.
The Right Dog for the Job project is working to understand better the genetics of New Zealand’s working farm dogs.
Led by Te Kunenga ki Pūrehuroa MasseyUniversity and supported by industry partners and the Ministry for Primary Industries (MPI) through the Sustainable Food and Fibre Futures fund (SFF Futures), the project aims to improve the health and performance of the country’s iconic working dog breeds, particularly huntaways and heading dogs.
The research team, led by Professor Matt Littlejohn from the School of Agriculture and Environment, has just completed a major milestone in the project by conducting whole-genome sequencing on 249 dogs.
This analysis uncovered 19 million DNA variations across the dogs sampled, which included 130 huntaways, 104 heading dogs and 15 crossbreeds.
Researchers said the goal was that the information would support future breeding decisions, helping farmers and breeders improve the genetic health of their dogs.
Identifying genetic risks
The main purpose of the research was to identify genetic variants (differences in DNA sequences) that could impact the health or performance of working dogs.
Many of these variants had been previously found in other dog breeds worldwide, but until now, little genetic research had focused on New Zealand’s working dog populations.
“Of all the variants linked to health traits in other breeds, we didn’t have much of an idea about what might also be carried by farm dogs,” Littlejohn said.
“Given the influence of breeds like the border collie on working dogs, we could guess, but using genome sequencing, we could know for sure, and there were a few surprises.”
Of the nearly 400 variants known to affect health or physical traits in other breeds, the study identified 27 variants present in the 249 dogs tested.
Among these, five health-related variants were found at a high enough frequency to warrant future testing.
An unexpected finding was the frequency of two of these variants, located in the CUBN and CLN8 genes.
While the number of carrier animals identified was not extreme (2 to 8% of dogs tested), the frequencies in New Zealand farm dogs are still higher than other international breeds.
The five key genetic variants identified are:
1. CUBN variant – causes cobalamin (vitamin B12) malabsorption, leading to serious health issues if untreated. Treatment is available, so proactive testing could help identify affected dogs and improve breeding decisions. Six carriers were identified.
2. CLN8 variant – leads to a neurodegenerative disorder causing loss of motor functions, seizures and blindness. Affected dogs usually need to be euthanised early. The frequency of this variant was quite high, with 21 carriers identified (mostly heading dogs).
3. SGSH variant – causes a neurodegenerative disease known as mucopolysaccharidosis IIIA, which has already been linked to Huntaways. Five carriers were identified, and routine testing for this variant is recommended due to the severity of the disease.
4. SOD1 variant – linked to degenerative myelopathy (DM), a disease that affects the spinal cord and leads to mobility loss. This variant has “variable penetrance”, meaning not all dogs with two copies of the variant will show symptoms, but the risk should still be monitored, particularly in huntaways. Forty-six carriers were identified.
5. VWF variant – causes Von Willebrand disease I (VWF1), which leads to excessive bleeding after injury or surgery. Nine carriers and one affected dog were found in the study. This variant also shows variable penetrance, but testing could still help prevent health complications.
Preventing genetic diseases
Huntaways, heading dogs and crossbreeds were sampled for the Right Dog for The Job project. Photo / Pam Stephen Photography
These genetic variants are recessive - a type of gene variant that only shows its effects when an individual has two copies of the mutation.
Dogs that carry a single copy are called carriers and do not show symptoms, though if two carriers mate, their puppies could inherit two copies of the variant, leading to health problems.
The study said farmers and breeders could minimise the chance of producing puppies that would develop these diseases by testing dogs for these variants and avoiding breeding between carriers.
The project’s findings were a step towards offering farmers and breeders tools for more informed and proactive breeding decisions, ultimately leading to healthier, more reliable working dogs.
During the next stage of the project, the research team will collect large numbers of DNA samples from additional dogs, as well as work with farmers and vets to measure health and working performance traits.
While the results above were based on known variants in other breeds, collecting trait data should enable the identification of new effects that may be unique to New Zealand farm dogs.
This information could be used to provide selection options for dog owners, not just to avoid genetic disease but potentially to improve desirable traits.
Support from industry partners
This research project received valuable support from MPI, as well as several industry partners, including Focus Genetics, Pāmu farmers and the New Zealand Sheep Dog Trials Association, who helped collect DNA samples from dogs across the country.
The study also received assistance from veterinary groups such as Vetlife, as well as genotyping services provided by Ancestry and The Helical Company.
