Texelplus delivers trait improvements

Texelplus delivers commercially valuable gains

Texelplus is the Society’s genetic improvement service, providing members with an objective way to assess the genetic potential of animals selected for breeding.

Performance recording in Texel flocks forms the backbone of improving genetic progress in the UK sheep industry, explains Society data and technical services manager, Ed Smith. “With 29% of sires used in the UK being Texels and Texel genetics present within more than 12% of the national maternal flock, the impact of improvements within the breed is vast across the wider industry.”

In 2020, 145 flocks recorded performance data on more than 7500 lambs, these were sired by 418 males out of more than 4000 genetic dams. The texelplus flocks bred 782 (30.7%) of the 2548 sires used to produce birthnotified lambs in 2020 and these animals sired 17,651 (33.9%) of the 52,048 lambs, he says

“Over the past 10 years, breeding values for early measures of growth: eight-week weights and scan weights have steadily increased in the recorded population. For animals born in 2020 that had data recorded, the average eight-week weight breeding value was 2.45 compared to 0.66 in 2011.

“This means that the average animal weighed 1.8kg more at eight weeks in 2020 compared to 2011 and would pass on half of this potential to its offspring. The figures for scan weights are similarly increased with 2020-born animals predicted to weigh almost 4.5 kg more at scanning compared to those born in 2011 (Fig. 1).”

For commercial lamb producers this genetic progress means that lambs by texelplus sires now have the potential to be 2.25kg heavier at 20 weeks old. “This extra gain is commercially valuable in a number of ways. Firstly, lambs are ready for slaughter quicker. This saves costs on-farm and often means lambs are sold when prices are better, meaning they are worth more too.

“In addition, lambs which are sold sooner help reduce a farm’s carbon footprint and give farmers the chance to better manage grass for ewes later in the year.”

Crossbred lambs sired by texelplus sires born in 2020 have the potential to be 2.25kg heavier at 20 weeks old than lambs by texelplus sires born in 2011.

Fig. 1. Trend in numbers of animals with a recorded scan weight and average scan weight EBV over ten years.

Average muscle depth breeding values have fluctuated over the last 10 years, but have been steadily increasing since 2013, says Dr Smith. “On average, animals that were scanned last year had a muscle depth EBV of 0.31, compared to 0.05 in 2011, indicating that animals born in 2020 had 0.25mm more muscle than those born 10 years earlier.

“Over the same period, the average breeding values [in scanned animals] for fat depth have decreased by the same margin: from -0.18 to -0.43, indicating that animals born in 2020 have 0.25mm less fat than those born in 2011.

“Collectively these changes in breeding values of recorded animals suggest that Texels born in 2020 grew faster and produced more muscle and less fat than the animals born a Individual texelplus member flocks can see the corresponding genetic trends figures for their own flocks through the reports page on iTexel, under the links for ‘Texelplus - My Flock Genetic Trends’.

“Here members will also find reports on individual male and female animals, with all their current breeding values listed; and whole breed reports including the top stock males and ram lambs reports,” he adds.

What is the Society’s Phenotype Farm initiative?

A proportion of texelplus members also form the Society’s Phenotype Farm Initiative that underpins the only genomic reference population in the UK sheep industry.

This initiative comprises 27 flocks that have their female population genotyped and phenotyped for the hard-tomeasure traits of footrot and mastitis. Each year between 500 – 1000 new animals are genotyped and their scores are added to the research data. To date more than 4000 pedigree ewes have been genotyped and phenotyped.

When coupled with the Society-funded ram registration genotypes, the Society now has access to genotypic data on more than 12,000 individual animals. While this is an excellent research resource, the Society’s aim is to publish genomic information on health traits, further supporting texelplus and the breed’s genetic progress. Further information on the Society breed development strategy can be found at https://texel.uk/breeddevelopment-15/

Commercial flocks

texelplus flocks also provide sires for the Society’s commercial phenotyping activity and for ongoing research activities. Each year a small number of sires are provided by the Society to commercial lamb producers, these are mated in single-sire groups to produce lambs of known sire. The lambs are reared and selected for slaughter onfarm with no input from the Society.

All lambs are sent to ABP for slaughter and the collection of VIA (video image analysis) data on their carcasses, continuing the data collection that was started in the Society’s VIA project completed in collaboration with ABP and SRUC. These data are stored by the Society to grow its VIA database.

The ultimate aim is to produce robust breeding values for Texel animals that will predict slaughter traits in commercial crossbred offspring. The VIA project developed the genetic parameters required to produce EBVs and demonstrated that Texel-sired lambs perform extremely well in the abattoir with 86.0% of more than 3000 lambs sired by 80 sires over two years classed as inspec. The VIA scanner is also able to accurately estimate levels of muscle, fat and bone in each carcass.