Sheep Ireland has been in existence now since 2009. So what has been delivered in this time? The objective of Sheep Ireland is to increase the profitability of Irish sheep farmers through genetic improvement. So has this been achieved?

Before we answer this question, it is necessary to paint the background to what is required to achieve genetic improvement. The first thing is data – sheep performance data – and lots of it. A database is required to host this data and facilitate the capture of future data.

Since 2009, Sheep Ireland has developed one of the best database and data recording web-screen systems in the world. This infrastructure forms the solid foundation upon which Irish sheep genetic improvement can be built into the future.

An excellent database is one thing; filling it with sound performance data is the next step. Sheep Ireland construct the €uro-Star indices using performance data collected from pedigree ram breeders and from commercial farms.

The vast majority of commercial data is collected from the Sheep Ireland Central Progeny test flocks (2,500 ewes across five flocks) and from Teagasc flocks involved in research and the Teagasc BETTER farm sheep programme. There are also a small number of independent commercial flocks involved in performance recording.

The data being captured from pedigree ram breeders is largely being recorded by each individual breeder themselves with annual visits to the majority of flocks from Sheep Ireland personnel to carry out ultrasound scanning of muscle and backfat.

Data integrity

The question is often asked – is data submitted by breeders trustworthy? To answer this question, we should assess if the current €uro-Star indices, which are formulated using this data, are capable of predicting sheep that will perform better in the future.

The answer to this question is yes. This is evident from the commercial farm data being collected by Sheep Ireland across the Central Progeny Test flocks over the past number of years, where significant differences are being seen between high €uro-Star index and low €uro-Star groups of animals (see Table 1).

It is also the evidence being found in the INZAC (Irish and New Zealand Across Country Comparison) research flock based in Athenry, where the high index groups of Suffolk and Texel ewes are significantly outperforming their low-index counterparts. These differences are currently being predicted by the €uro-Star indices based on the current data available to Sheep Ireland, and this illustrates that there is significant value to the data being collected from Irish pedigree ram breeders.

Is sheep genetic improvement being maximised in Ireland?

The answer to this question is unfortunately no. Based on the latest DAFM sheep census, there are just over 83,500 breeding rams in Ireland. Somewhere between 25% and 33% of these rams will need to be replaced annually (requiring between 21,000 and 28,000 replacement rams annually).

At present, 12,500 pedigree ram lambs are being performance-recorded annually through the LambPlus programme (this number is growing annually). This number of performance-recorded rams falls well short of meeting the annual ram demand for Ireland. Combine this with the fact that a large number of these 12,500 ram lambs will not make it as breeding rams due to physical faults, poor €uroStar indices, etc.

Genetic progress in hill sheep

The vast majority (95%) of these performance-recorded ram lambs are from lowland sheep breeds. Unfortunately, the uptake of performance recording among ram breeders in our hill areas is not where Sheep Ireland would like it to be.

The absence of formal flockbook structures, where the parentage of purebred lambs born annually is captured and recorded on to a database, is the major first hurdle that must be overcome in order to facilitate performance-recording of hill sheep.

Practical difficulties associated with recording data in hill areas (lambing outdoors, etc) is one of the main issues that has prevented this from happening.

This, coupled with the marginal returns from this system of sheep farming in recent decades, has dissuaded many hill ram breeders from engaging in performance recording of their sheep.

The reality is that in Ireland many rams are purchased annually with no background information recorded on them. Compare this situation with the Irish suckler industry, where almost 90% of bulls in use on farms are pedigree registered bulls with known back ancestry. This high level of usage of pedigree bulls and the ancestry information that it provides helps to track the top-performing bloodlines, protect against inbreeding and allows genetic indices to be produced. Without animal ancestry information, genetic indices are not possible.

Where next?

In order to increase the rate of sheep genetic gain in Ireland, we need to increase the volume of performance records being collected annually. More performance data will help to make the €uro-Star indices more accurate for Irish farmers and will increase the rate of gain we make as an industry.

Our sheep breed societies need to continue to support sheep breed improvement. The CPT programme has invested heavily in the generation of performance data for our main sheep breeds and the high-index progeny test rams that come out of the CPT annually need to be promoted within each breed society for the benefit of Irish commercial sheep farmers.

Irish ram breeders will provide what Irish sheep farmers demand, so it is critical that greater numbers of Irish sheep farmers look for more than a physically correct “good-looking” ram – this should be the minimum requirement of any ram purchase. Good looks simply do not tell us anything about the potential future performance of a ram.

However, if we have data on that ram’s siblings and ancestors, then it is very possible to predict how a ram is likely to perform and this is how the €uro-Star indices are constructed.

How genetic indices work

Indexes can be made sound very complicated, and the construction of them is. However, the way to use and understand indexes is really simple. The €uro-Star indices are a prediction of future performance based on past performance. If a particular bloodline has very high average growth rates, it is likely that future generations of this bloodline will have high growth rates. The same applies for all traits.

There will be exceptions to this rule. Individual animals may not live up to the potential of their genetic index. More data may be recorded on a bloodline, which changes the initial predictions made. This can result in movement in an animals €uro-Star index, something which can be very frustrating for ram breeders and buyers alike.

It is important that users of the indices realise that this can and will happen on occasion, especially given the fact the level of performance data available is building from such a low base. As more data is generated going forward, this will lead to more stable genetic evaluations for the industry.

Using a team of high-index breeding sires is a well-accepted and used concept among Irish dairy farmers. These teams are used when there is not a lot of data available on particular bulls and their bloodlines. This approach spreads the risk associated with one bull’s index dropping. Even though one or two bulls may drop, the herd will still make genetic progress as the team average index remains high.

Most Irish sheep farmers use a number of rams annually, so this team’s concept is very applicable.

Summary

Genetic evaluations work. This has been shown in other sheep industries and in other animal sectors in Ireland.

The Irish €uro-Star sheep indices are working. This is being shown by the Sheep Ireland Central Progeny Test and the INZAC flock in Teagasc.

€uro-Star indices for individual rams may move, but by consistently purchasing high-index breeding rams, a flock will make genetic progress, leading to higher flock performance at farmer and national level.

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Special focus: sheep breeding and sales season

For the upcoming 2017 ram sale season, we urge farmers to include the €uro-Star indices as one of the selection criteria to improve the genetic makeup of the flock and overall farm performance.