February 2015

So far this winter does not look too bad. Following on from a good grass growing autumn, the ewes are in excellent condition. To protect the spring grass, all ewes were housed mid January, fluked and scanned. I had been anticipating some fertility knock on from the wet weather we have had over the last couple of years, and as a result have drenched with a trace element product from JG Animal Health prior to tupping for the last 3 years. Analysis of some of our fields in the summer indicated increasingly low Selenium (Se) levels in particular. The January scanning confirmed my concern. Over the last 3 years we have averaged c.190%. This year 180%. Not bad in itself, but a substantial rise in singles and a similar drop in 3’s. For some this looks like lots of big early lambs for market, but for us as breeders of replacements, not so good. Now to be fair we added an abnormal number of shearlings this year, which might well have had an influence. Indeed over 75% of the breeding ewes have had 3 lactations or less. This has been a deliberate policy to take advantage of some impressive new rams brought in over the last couple of years. I would expect the average age of the flock to increase (normalise) over the next couple of years.

Another effect of reduced levels of Se is that it can have an impact on an animal’s natural immunity. Under particularly adverse conditions even vaccinated sheep can still become susceptible to pathogens. We need to see how long it will take for these trace elements to naturally rebuild in the soil. In the mean time boluses look like the answer.

Back in September, with other members of the Performance Recorded Lleyn Group (PRLG), (http://performancerecordedlleynbreedersgroup.wordpress.com/) and working with EBLEX and Glasgow University, we participated in a really interesting new trail analysing the heritability and genetic connectivity of roundworms in sheep. The traditional approach has been to do this via FEC analysis. This new study looks to ascertain whether a more robust metric might be found by analysis of a lamb’s saliva. This year’s trial among members of the PRLG covered a total of well over 2500 ewe lambs, which should produce some meaningful hard data. As the trail continues, it is hoped that increasingly it will be possible to remove the theoretical 10-15% of sheep that are primarily responsible for spreading worms on the grassland. Existing Signet FEC EBVs data already have obvious commercial implications. (see the link below to a pdf for an interview in Octobers 31st Farmer’s Guardian).

Improving the totality of the flock through performance recording and EBVs | Features | Farmers Guardian

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