At Kentish Downs we believe genetics play a significant role in productivity and profitability. Research has shown many carcase traits are moderately to highly heritable and provide good opportunities to improve breeding programs.
Our focus is on increasing the potential of Kentish Downs Poll Dorsets to generate more profit for our clients. We are achieving this goal through targeted inclusions of stud sires and we have an extensive breeding and performance program, which combines a selection of the best quality sheep using both visual and Lambplan data to produce rams of the highest quality.
Sheep Breeding Values Explained
Australian Sheep Breeding Values (ASBV's) are an estimate of an animal’s true breeding value based on pedigree and performance recorded information. They are essentially a projection of how that animals progeny will perform for a range of traits. This is more effective than raw data as it accounts for environmental (i.e. feed, management, seasonal) effects.
Australian Sheep Breeding Values (ASBV) are an estimate of an animal’s true breeding value based on pedigree, genomic and performance-recorded information for a range of traits.
ASBVs allow for selection of traits that cannot be visually selected in a live animal. They can be used in a breeding program to improve the performance of future generations, or to purchase stock that are likely to be more productive and have better eating quality, lean meat yield and colour.
We select with both ASBVs and visually, as both are equally as important. We make sure to collect all this data in the most accurate way possible, ensuring the ASBVs generated from this data are of high accuracy.
Growth Breeding Values
Weaning Weight (kg) WWT
Estimates the genetic difference between animals in live-weight at 100 days of age. The higher the better.
Post Weaning Weight (kg) PWT
Estimates the genetic difference between animals in live-weight at 225 days of age. The higher the better.
Yearling Weight (kg) YWT
Estimates the genetic difference between animals in live-weight at 360 days of age.
Post Weaning Fat Depth (mm) PFAT
Estimates the genetic difference in GR fat depth at 45kg live-weight Desired level depends on breeding aims. Should not be extreme either way.
Post Weaning Eye Muscle Depth (mm) PEMD
Estimates the genetic difference in eye muscle depth at the C site in a live-weight animal. The higher the better.
Yearling Eye Muscle Depth (mm) YEMD
Estimates the genetic difference in EMD at the C site at 60kg live-weight Level depends on breeding aims.
Yearling Fat Depth (mm) YFAT
Estimates the genetic difference in GR fat depth at 60kg live-weight Level depends on breeding aims. Should not be extreme either way.
Eating Quality and Meat Yield
Lean Meat Yield (%) LMY
Rams with more positive LMY ASBVs produce lambs that have a higher Lean Meat Yield percentage at slaughter.
Intramuscular Fat (%) IMF
Rams with more positive IMF ASBVs produce progeny with higher levels of intramuscular fat. (IMF is a measure of the chemical fat percentage in the loin muscle of a lamb and is often referred to as marbling. IMF has been shown to have a significant impact on the flavor, juiciness, tenderness and overall likeability of lamb).
Shear Force (kg) SF5
Rams with more negative SF ASBVs produce lambs with more tender meat. (Shear Force is a measure of the force or energy required to cut through the loin muscle of lamb after 5 days of ageing, the ASBV is reported in deviations of kilograms of force.
Birth Weight (kg) BWT
Estimates the genetic difference between animals in weight at birth. In terminal (White Suffolk) sires, the lower the better, as this decreases the chance of having lambing issues. But extremely low can also be a problem (more so in non-terminal breeds).
Maternal Weaning Weight (kg) MWWT
Estimates the genetic difference between the animals daughters weaning weights and their potential to provide milk and a better maternal environment. The higher the better.
Artificial insemination and using Matesell allows single mating of one sire to selected ewes allowing Craig to fine-tune the breeding of rams which will then be offered for sale. All sheep have been DNA tested to allow the accuracy of data and pedigree. The sires used in the 2021 mating average in the top 2% of the Lambplan database for the Terminal Carcass Production Index.
In the near future, Kentish Downs plans to expand, increasing from joining 600 Poll Dorset ewes this year to 800 next year and potentially 1000 the year after.
“Applying the data to achieve genetic gain is very rewarding experience and one that others will benefit from as well,” Craig said.
Large scale solutions, communication, and quality genetics, we believe we can offer our clients the full package.
To breed Poll Dorset sheep that have the right balance of structural integrity and industry leading genetics to maximise profit right through the entire Prime Lamb supply chain.
To use Lambplan to benchmark across the Terminal Lamb Industry and use the most up to date technology to achieve our genetic gain objectives with maximum consideration of environmental and animal welfare outcomes.