Breed Enhancement

The WHSS Signet Recording Scheme is now well established and for those members who are interested in joining the scheme or buying recorded stock here is a report on progress so far and details on how to join the scheme.

Wiltshire Horn Performance Recording Update

Introduction

This report provides an overview of the achievements in performance recording Wiltshire Horn sheep to date. The Signet Breeding Services Wiltshire Horn dataset now includes detail from 14 flocks and a total of 432 ewes and 8 - 900 lambs per season.

The following Wiltshire Horn flocks are currently involved in performance recording:

If you wish to know more about buying recorded stock or start recording your flock, give any one of us a call; contact Sam Boon at Signet Breeding Services Tel: 0247 647 8829 or see http://www.eblex.org.uk/returns/

Performance recording provides an independant method to assess the breeding merit of animals in your flock.  This is evaluated using Estimated Breeding Values (EBVs) which indicate the genetic superiority or inferiority for a specific trait. EBVs provide important information to make informed breeding decisions and act as a valuable marketing tool. Importantly, they provide a way to add value to your rams at sales, at home and on-line. It is now possible to research details of any individual Wiltshire Horn Sheep included in the Signet Recording programme on the Basco website.  http://www.egenes.co.uk/bascosearchsheep/search/quick  Recording will quickly identify genetic strengths and weaknesses within any flock relative to all other recorded animals within the breed.  It will also identify elite ewes with potential to produce a future stock sire.

When a new flock starts to record, EBVs of sheep brought in from a recorded flock are transferred to the new flock. Sheep with a recorded sire, dam or grandparents receive initial EBVs based on their relatives’ performance. Sheep with no known records receive initial EBVs based on average genetic merit of other animals with unrecorded sire and dam of similar age and sex. Once progeny have been produced these starting EBVs are likely to change rapidly.
 

The Wiltshire Horn Breeding Index has been designed to enhance the productivity and  profitability of Wiltshire Horn sheep by increasing the weight of lean tissue in the carcase, whilst minimising any associated rise in carcase fatness and enhancing the maternal ability and prolificacy of ewes retained for breeding purposes. The Breeding Index is calculated by combining EBVs, using appropriate economic weightings, into a single figure that highlights an animal’s breeding potential for a specific breeding objective. EBVs indicate the superiority or inferiority of genes an animal possesses for a specific trait compared with other animals in the same evaluation. The EBVs for an animal are influenced by measurements relating to the trait, related traits and information collected on relatives. The Wiltshire Horn Breeding Index provides EBVs for:

• Litter size (lambs born live or dead/ewe)
• 8-Week weight (kg) (selection on high 8-week weight EBVs result in faster growing lambs to weaning)
• Maternal ability (kg) (component of 8-week weight measure;  high figures indicate females performing well as mothers – maternal care and milking ability)
• Scan weight (kg) (selection on this trait will increase growth rate to scanning at 21 weeks of age)
• Muscle depth (mm) (selection for high muscle depth will increase lean meat content of carcase)
• Fat depth (mm) (selection for low or negative measures will reduce fat levels or enable lambs to be taken to higher weights without becoming overfat)
• Mature size (kg) (gives breeders chance to influence the mature size of their flock) 

Wiltshire Horn National Breeding Evaluation Report Signet Breeding Services provides a copy of the annual Breeding Evaluation Report to each recorded flock. The Report includes a listing of the top recorded stock sires and top ram lambs within the breed. The report also includes a Breed Benchmark for the breed for the year, illustrating the difference in breeding potential for each EBV between the top and bottom 1%, 5%, 10% and 25%. The Benchmark also gives the breed average for each EBV assessed. Lists of top recorded stock sires and top recorded ram lambs in index order are followed by results specific to one’s own flock. All ram and ewe lambs produced by ewes in your flock in the current season are listed in identity order together with their individual EBVs and Index. The report goes on to list and provide up to date data on shearling rams, shearling ewes, stock ewes and stock rams in your flock. Finally lamb genetic trends and ram progeny numbers for the flock, for each year recorded are tabulated for quick reference.
 

‘High Five’ Wiltshire Horn Ram Lamb Report For the second year running Signet produced a special ‘’High Five’ Wiltshire Horn Ram Lamb Report’ listing the top five ram lambs from the 2010 lamb crop in each recorded Wiltshire Horn flock in the country as a guide to both commercial and pedigree breeders that are interested in purchasing a recorded Wiltshire Horn ram. This report has provided a useful way to promote recording in other breeds and it is hoped the same will be true for Wiltshire Horns.

Breeders meet annually with Signet consultant Sam Boon to discuss the Reports and their interpretation, progress to date, plans for future recording and continued co-operation between flocks. Following discussion at the 2009 meeting the Wiltshire Horn Breeding Index was updated ahead of the 2010 recording year, placing slightly less emphasis on prolificacy in order to reduce the incidence of triplets in favour of twins. In addition increased emphasis was placed on other important traits such as carcass quality, lamb growth rate and maternal ability.
 

Shedding Data Recorded flocks regularly submit data on shedding characteristics of shearling ewes when shedding takes place at approximately 12 months of age with the aim of evaluating this trait in individual animals and developing a shedding EBV.  Signet is working with Wiltshire Horn breeders to investigate the genetics associated with shedding, identify the optimum time and way to score the trait and over time identify whether or not high scoring animals produce the highest percentage of shedding progeny in pure and cross breeding programmes.  A group of Wiltshire Horn recorded flocks won a Genesis Faraday Spark award to investigate the genetic influence on wool shedding.  These data on shedding will represent an important contribution to progress with this study.

2013 Update on Wilts performance recording group

Since the group got together in 2005 we have made remarkable progress, we have gained and lost a few members on the way but now have a stable and established breeding database, producing animals with reliable EBV’s. It’s reassuring to hear Sam Boon of Signet say of the Wiltshire Horn recording group---- ‘Rates of genetic gain are really good for a breed at this stage in their breeding programme’.

It’s very easy to confuse ourselves with quotes about rising EBV’s and percentage gains so I will try to sum up our modest achievements in terms that we should all be able to appreciate

In the 8 years since we started our lambs are now, on average;

0.6kg heavier at 8 weeks old
1.32kg at 20 weeks old
Have 0.68mm more eye muscle depth & 0.31mm fat depth at 20 weeks old

That may not sound like much gain for 8 years of work but if that is translated into meat yields over a flock then it starts to look like an appreciable gain. For instance on a UK average flock size of 368 ewes (EBLEX stats) with 1.59 lambs reared /ewe it makes a big difference

368 ewes X 1.59 lambs raised X 1.32kg = 772 kg extra meat at 20 weeks old---if these animals are being sold dead weight at £3.60/kg (assuming 50% kill out) that’s £3.60 x 772 kg /2= £1389.60 extra income in a flock

So we are moderately pleased with our success and are working together to improve the accuracy of our data by using ‘link’ rams across all flocks. This use of common genetics allows a better comparison of sheep across the recorded breed rather than just within a single flock.  

We are also encouraging extended use of ultrasound scanning of muscle and fat depth in lambs to again increase accuracies of EBVs (estimated Breeding Values)

Farmers are just beginning to realise that there is a high cost to wool production that is not nearly covered by their income from wool, this coupled with a better understanding of performance recording means that there is a steady increase in the use of performance recorded wool shedding sires. This demand is led by commercial farmers who want to breed the wool off their stock with a high index Wiltshire tup but also includes many pure bred Wiltshire flock masters with a desire to improve their flock
 

Future plans

• Continue flock recording including scanning at 21 weeks of age
• Continue to improve linkages across all recorded flocks by exchanging or sharing rams
• Improve genetics of top ram lambs by putting the top 20% of ewes to higher EBV sires
• Provide a wider spread of shedding data by scoring earlier when only 20% of shearling ewes have fully shed
• Encourage more breeders to start recording their flocks
• Explore opportunities to increase the number of flocks collecting faecal egg count data with the aim of producing a worm resistance EBV some time in the future 

The Wiltshire Horn Recording Group hold regular open days, please contact any of the breeders for details.

To view the Wiltshire Horn Genetic graphs plese refer to the DOWNLOADS page where you can download them.