Genotyping Case Study: The Benefits Of Sheep Parentage Testing

Genotyping Case Study: The Benefits Of Sheep Parentage Testing

Livestock Genotyping and DNA Analysis

As their flock began to grow, New South Wales farmers Stacy and Gary Cullinan needed a more reliable way to assign parentage to their sheep.

Client background

Stacey and Gary took over the Carstairs station in the Pooncarie area of western New South Wales from Gary’s father in 1997. The property has been in the family for 100 years. The farmers have 250 head of mixed cattle on their station and, since 2000, have run dorpers under the banner of Dust’n Rain Dorper and White Dorper Stud. They run around 750 white ewes and 250 black ewes and also have approximately 4,000 breeding ewes in a commercial flock. They breed around 450 rams per year and, later in 2024, will host their 5th on-farm ram sale.

Having never used genetic testing before, Stacey approached XytoVet last year to begin the process of allocating parentage for their lambs using parentage testing based on genomic DNA data.

The problem

The impetus for Stacey and Gary deciding to explore genetic testing was the growing size of their flock, which was making it increasingly difficult to catch the ewes lambing and then match them to their progeny. Although they had used an AI program for one mob of ewes in the year prior, they tended to prefer using traditional breeding methods.

The solution

Sheep parentage testing uses multiple genetic markers to accurately determine whether a specific dam or sire is the true biological parent of a given animal. Other methods of parentage assignment, such as visual assessment, are often prone to error, and incorrect parentage assignments can have a year-on-year cumulative negative impact on your flock.

With the use of genetic data to determine pedigree, Gary and Stacey have been able to add more stud rams to their breeding program, which works more effectively in paddocks as large as theirs. With the assistance of the BreedELITE software, it’s also easier to identify the ewes that are not having lambs and subsequently remove them from the stud.


Already, Stacy and Gary are recognising the benefits that DNA information can bring to their farming system.

Dust’n Rain will be sending us 1,000-1,300 samples from this year’s lambing drop. XytoVet returns data for 99.9% of samples received at no additional cost. Having tested their entire flock, Stacey says that she believes they are getting 100% parentage matches from their testing, which has made both Gary and Stacey feel more confident about the business decisions they’re making.

They encourage anyone breeding stud sheep to use genetic data to make more informed breeding decisions.

XytoVet and the role of genomic testing

Sheep parentage testing is an invaluable tool that provides farmers with greater visibility over the genetic diversity within their flock, helping drive productivity and profitability.

XytoVet is a leading provider of genotyping services for sheep in Australia. Contact us today to find out how we can help your flock.

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