Mark Exelby

Recorded rams pay dividends for organic farm

Mark Exelby Hutts Farm – Case Study 2020 - Soil Association Organic Farmer

The use of high genetic merit rams was easily worth an extra £4/lamb for this May lambing, organic enterprise – but different rams generated this benefit in different ways. For some rams, progeny were finished faster or at heavier weights and for others premiums were earned through superior carcase conformation. In each case, improvements in performance could be explained through the EBVs (Estimated Breeding Values) used to aid ram selection decisions; breeding values that are available to any commercial ram producer.

Introduction

Mark Exelby, of Hutts Farm near Ripon, was enthusiastic to join the RamCompare project wanting to improve the overall production of his organic sheep enterprise.

His objectives were to:

• Sell all progeny deadweight from August to February
• Sell 170-180% lambs per ewe
• Grade lambs at R3L or better

Lambing outdoors in May, Hutts farm has recorded 1,160 lambs over the last two years from 17 rams, using six different breeds.

Achieving performance targets

After two challenging summers, lambs were drawn in large batches from September onwards having been finished from red clover leys. Lambs grade consistently with over 86% being R2-3L or better and a killed within a five month slaughter period. Managed as one group, these large batches provide a highly accurate analysis; with over 40 lambs slaughtered per sire.

The table below shows this dataset has achieved goals set for the farm and from the project with targets of 15-22kg deadweight with a conformation target of R2 or better.

• Over 86% of project lambs slaughtered achieved market specification
• Note that the average carcase weight for each sire is also variable, varying by about 1kg

Amongst these sires, it is worth highlighting the performance of Lowereye Stallone, 17ZVY03456  bred by Neil Oughton. This ram is currently in the Top 1% of the Charollais breed for Muscle Depth, CT Lean Weight and CT Gigot Muscularity – a true muscle machine – and this is exactly what this independent assessment of carcase conformation showed. He is the top ram used to date at Hutts farm for carcase conformation, achieving 62% U and 38% R grade carcases in comparison to a Charollais farm stock ram with average EBVs for muscling, that achieved only 10% U grade carcases.

Using Scan Weight EBVs to reduce days to slaughter

A ram’s genetic potential for growth rate has a big impact on the speed with which his progeny reach slaughter weight. This can be observed in the chart below, showing the relationship between a ram’s Scan Weight EBV (an indicator of his genetic potential for growth rate) and the time taken for his progeny to reach slaughter weight.

In the example above, the Meatlinc HRF:09012, provided by George Fell, gave almost a two month advantage over some of the lower performing sires. A cluster of Suffolk sires, led by HRH:14:00334, Sampfordel Hero bred by Kathleen Hill, also produced very fast finishing progeny.

Using carcase weight breeding values to increase carcase yield

At Hutt’s farm it was observed that rams with high breeding values for carcase weight had heavier progeny. There was over a 1kg difference in carcase weight between sire groups and much of this could be explained by their genetic merit.

Again the top ram tested to date is the Meatlinc ram HRF:09012. He currently sits in the top 5% of his breed for growth rate and as we have seen already, he has one of the best breeding values for days to slaughter.  A number of Charollais sires from the Rainbow, Rutland, Elmwick and Lowerye flocks have also performed well for this trait.

Placing a value on improved performance

Within the project, the overall genetic merit of rams is assessed using the “Carcase Merit Index” a breeding index that takes into account a ram’s genetic  potential for carcase weight, conformation and fat classification. As seen here, this breeding index explains much of the variation observed in the value of lambs by different sires, with a cluster of the top rams being those already highly rated for carcase weight.

This data shows that using a ram with a high Carcase Merit Index will increase lamb values, with a potential gain of £4/lamb seen each year from using the best sires.

Blending lamb enterprise objectives

We know rams have different characteristics. This can be clearly seen on the chart below, which plots the breeding merit of each ram for carcase value (using the Carcase Merit Index) versus days to slaughter.

There tends to be a trade off in these characteristics. Some rams will have progeny with faster growth rates, but less valuable carcases; some will produce higher quality carcases over a longer finishing period.

From the graph below the Meatlinc ram HRF:09012 stands out as a nice example of a ram that achieved both. With a combination of high breeding values for scan weight and carcase attributes his progeny not only had high quality carcases, but also finish quickly - two weeks in advance of the rest of the flock. This is a ram who is clearly multi-tasking.

A commerical perspective

Commercial Farmer Mark Exelby comments, “Over the last two years we have enjoyed being part of the RamCompare project. It has been interesting working alongside the other commercial farmers who are part of this project and seeing how the different systems from across the UK have all seen the benefits of using superior performance recorded sires. We have been impressed by the integrity and professionalism of all involved in the RamCompare programme.”

“From Hutts farm we have seen an improvement in carcase conformation and carcase weight, this has been coupled with a reduction in days to slaughter. A triple whammy! We have some fantastic lambs on the ground now and are excited to see how they do this year.”

“The sheep industry in this country needs to up its game - we used to be leaders in this field. Any serious lamb producer needs to be buying rams with a high genetic potential, this cannot be done by looks alone. RamCompare has proven and continues to prove that EBV’s provide an accurate guide to rams genetic potential and therefore are a valuable and useful tool when buying a sire.” He concludes.

Key messages:

• There are large genetic differences between rams of the same breed. Exploit these differences to increase flock profitability.
• At Hutt’s farm the progeny by the highest genetic merit sires were easily worth an extra £4/lamb, this could be worth an extra £800 over a ram’s lifetime.
• Before selecting a ram, review the performance of your lamb crop and consider which aspects of performance you wish to improve in the future.
• Use EBVs to select sires with superior genetic merit. Information is readily available at signetdata.com and www.itexel.uk (for Texels).
  • To reduce days to slaughter select rams with High Scan Weight EBVs
  • To increase carcase weight and overall carcase value, select rams with high Scan Weight EBVs and superior breeding values for muscling traits like Muscle Depth and CT Lean Weight.
• As always, ensure that rams are structurally sound and healthy. Avoid bringing disease onto the farm. This will ensure your investment in superior genetics will be repaid for many years to come.