Terminal Genetics at The Willows
Terminal genetics have historically made up the bulk of our stud flock at The Willows.
The purpose of a terminal ram is to produce lambs that are suited to slaughter - The exact traits that are desirable differ slightly between different enterprises and production systems - But the average terminal ram will have a focus on fast, early growth and deep eye muscle, with enough fat to ensure high eating quality and finishing ability in lambs but not so much that lean meat yield is affected. The balances of these traits within a ram vary depending on your own system. If you are turning your lambs off as suckers then you want a ram that has high early growth (WWT) and aren't so worried about later growth (PWT). If you want a ram to join to Merino ewes to produce a first cross lamb then you would look for a ram who has a low birth weight (BWT), good growth and muscle figures (PWT/PEMD), and a higher level of genetic fat (PFAT). If you are joining to first cross or crossbred ewes for a prime lamb then you will focus mostly on high growth and high muscle, while making sure the ram isn't so lean that you sacrifice eating quality or can't finish the lamb.
In comparison to the average across all terminal sheep in the Sheep Genetics Database, our flock is
1. Below average for birth weight.
2. Above average for growth
3. Above average for muscle
4. Above average for fat
There is a trend to breed for leaner animals to increase lean meat yield (LMY) as seen in the terminal average for PFAT which is very lean. However this has its own issues - genetic fat has a strong link to the ewes resilience and ability to do well in difficult environmental conditions, the survivability and weaning percentages of her lambs, and the IMF (intramuscular fat) and eating quality of the lamb once it hits the table; Hence we have chosen to select for genetically fatter animals who are still lean enough to produce acceptable LMY. We are always striving to produce low birth weight sires that grow fast, have excellent muscle but have enough fat that their progeny finish easily.
Our only link to eating quality data currently is through DNA testing and linkage with the CRC nucleus flock. We will pursue this more as more practical mechanisms to measure eating quality become available.
We believe eating quality will have to be seed stock driven as the reality of getting feedback from the processors is a long way off - dentition, weight and fat are still the only feedback we receive from 90% of processors when we sell prime lambs. Through the sale yards we receive no feedback.
Interestingly, through the saleyards our own prime lambs are marketed by our agents as Poll Dorsets and when I asked Landmark and Elders why this is the case, the comment was "All second cross lambs are called Poll Dorset because we can't tell the difference between a White Suffolk and a Dorset out of a Crossbred ewe - but all the first cross lambs out of Merino ewes are called White Suffolks, as this is the dominant cross and again we can't tell the difference either way."
We actually have Poll Dorset ram clients and a well known livestock buyer who calls our sheep clean faced Poll Dorsets.
All of our terminal rams are weighed and tagged at birth which ensures accuracy in their growth figures and pedigree. They are weighed at weaning and again at post weaning, and muscle and fat scanned at post weaning. All of our stud sheep are run under commercial conditions to ensure they have the resilience and toughness to perform under pressure. We use our own ram lambs over our commercial ewes to test their performance and also use ram lambs over a large percentage of our stud ewes to accelerate genetic gain. We join our ewe lambs at 7-8 months of age which again increases the rate of genetic gain and is also a good measure of fertility and early growth.
Our stud flock are predominantly White Suffolk genetics which carries advantages, one of which is clean points. This reduces any seed infestation around the head of the lamb. White Suffolks are also known for their ease of lambing which combined with our own flocks well below average birth weight ASBVs, results in huge reductions in Dystocia and lambing issues. Within our stud flock of 800 ewes last year, we pulled lambs from two ewes, both of which were multiples with misrepresentation. We didn't pull any single lambs. We cull heavily on conformation and this is assessed a number of times throughout the growth of the rams. We favour rams with a triangle shaped barrel from neck to tail when viewed from above, as this promotes ease of lambing (narrow shoulders), and ensures the bulk of the meat on the carcass is concentrated over the higher value cuts - loin, sirloin, leg etc. It also takes some weight off the front legs which are more prone to breaking down compared to the stronger rear end. We have clients and lamb buyers who are wedded to the concept of breed being more important than the designed genetic package of DNA and call our rams clean faced Dorsets - which is fine by us. We have used Poll Dorset genetics at times - Interestingly the industry leading Poll Dorset ram Pollambi 451-11, who may well be the greatest game changer ram for the Poll Dorset breed in history, actually had a White Suffolk mother. Here I rest my case! It is the genetics a ram can offer that are important – not the breed.
We also run an AI program each year to greatly accelerate genetic gain and introduce new blood into the stud. This is detailed more on the AI Program page.