The run up to mating is a good time to critically assess ewe body condition score (BCS).
The measurement is important in terms of ewe reproductive performance, with flocks that achieve target BCS at mating (BCS of 3.5 for lowland ewes and 3.0 for hill ewes) recording a higher litter size, lower barren rates and a more compact lambing spread.
Numerous weather-related challenges over the last year to 18 months has affected ewe performance (see pages 34-35), with a higher percentage of ewes requiring preferential treatment. However, there are often scenarios on farms where a significant percentage of ewes are under-performing despite adequate nutrition.
Thin ewe study
Teagasc and the Department of Agriculture Regional Veterinary Laboratories are currently undertaking a Thin Ewe Study, which aims to get to the root of the cause of ill thrift/poor BCS in ewes.
Of particular interest is investigating if iceberg diseases are linked to poor performance, or if more common issues, such as broken mouths/poor teeth or parasite burdens, are the major contributors to the lack of thrive.
So-called iceberg diseases are diseases (or sub-clinical diseases) which result in sick sheep without any apparent cause – with the only visible sign being poor performance and ill thrift.
There are five main iceberg diseases, including Maedi-Visna (MVV), Caseous Lymphadenitis (CLA), Border Disease (BD), Ovine Pulmonary Adenocarcinoma/Jaagsiekte (OPA) and Johne’s Disease (JD).
It is believed that the impact of these diseases is low, but unfortunately there appears to be anecdotal evidence suggesting they are increasing in frequency and this is what the study aims to establish.
In addition to ill thrift, these diseases can manifest in numerous ways, including pneumonia, chronic mastitis, progressive weight loss and infertility, abortion, higher mortality, etc. Establishing the cause of the problem is the first step in putting a control programme in place.
The Thin Ewe Study allows flock owners to send up to three live, thin ewes to their local Regional Veterinary Laboratory (RVL) for euthanasia and examination, with a view to reaching a possible diagnosis.
There will be no charge/cost for the flock owners submitting ewes for the study.
A report will be sent to a nominated vet, who in turn will share it with the flockowner, and this can be made available to your Teagasc adviser.
Ewes must be pre-booked and this can take place via your Teagasc adviser, or by contacting your local RVL.