Having your ewes in the correct BCS is the key to a successful mating and lambing performance. It is important to remember that it is not something that can be changed overnight. The target BCS for a lowland ewe is 3-3.5 at mating, but I would be pushing for 3.5.
Hill ewes will be anywhere between 0.5 to 1 full condition score less than this.
Getting this wrong will reduce the number of live lambs born, increase the number of barren ewes and increase the length of the lambing period.
Having ewes over or under-conditioned at mating can cause problems, but generally it is under-conditioned ewes that are the main concern.
Data from Britain suggests that one in five ewes will have a BCS of less than 2, while only one in 25 will have a BCS of 4.5 or 5 at mating.
An excessive number of thin ewes in the flock usually results from delayed weaning, poor quality and/or quantity of grass or underlying health problems.
Results from Dr Tim Keady in Athenry show the importance of BCS at mating. His research found that a one-unit increase in BCS led to an increase in weaning rate of 0.1 lambs per ewe.
With good grass a ewe will gain one condition score in approximately six weeks, but with poorer quality grass it may take 10 weeks. Addressing this now will eliminate a lot of problems later in the year.
In addition to having ewes in the correct BCS, it is also important to have them increasing in condition coming to mating.
This is achieved by increasing the plane of nutrition or flushing the ewes.
Flushing is a long established management practice but results can be variable. Flushing ewes generally gives better response with mature ewes than hoggets, prolific breeds tend to be less responsive, thin ewes respond better than over-fleshed animals, and the greatest response occurs at the beginning and end of the breeding season.
The main reasons for culling include, broken mouths, mastitis, prolapses, persistently thin ewes, persistent lameness and infertility. Culling for mastitis is a no-brainer and there are quite often a few cases of this after weaning so be vigilant and ensure these ewes are removed from the flock.
There will be enough issues at lambing time without lambing down ewes that can't milk. Ewes which prolapsed should be culled and that is our policy at Lyons. Previously, any ewe which prolapsed was ear notched immediately, making it very easy to identify her when it came to selecting breeding stock.
Now, with the use of EID and the handheld reader, this identification is done electronically, removing the need for ear notching, but the end result is the same. You can't depend on spray markers or remembering tag numbers to do this job.
Persistently lame sheep should also be culled. They increase the workload, lead to reduced performance and this is not something you want to retain within the flock.
If there is a large percentage of lame sheep in the flock then it would point to a management issue, and there is no point in penalising the sheep for this.
Persistently thin animals should also be removed from the flock as this may be indicative of underlying health issues. You should not select thin ewes for culling at weaning, as the thinnest ewes at weaning generally result from rearing large litters. Give them at least four weeks and then look at them again.
What ewe type should we select?
Again, there is not a single correct answer to this question. At Lyons we are positive towards the Belclare cross and it is the breed I use on my own small-scale enterprise, mainly because of the increased litter size it offers.
Is it the only breed that offers this? In a word, no.
Data from Seamus Hanrahan's research (formerly of Teagasc, Athenry) shows a range of other breeds such as Lleyn, Mule, Charollais and Vendeen also offer alternatives.
Indeed, even without changing breed type, the current make-up of the Irish flock is capable of weaning a much higher lamb crop than what is currently achieved.
A charge that is often levelled against the Belclare is the slower growth rates of their progeny. Teagasc data quoted at the recent open day on John Kelly's farm in Baltinglass would suggest that progeny of Belclares are 1kg to 1.5kg lighter at weaning.
The Hanrahan data indicates a weaning rate of 1.7 lambs per ewe. This is approximately 0.4 lambs above the national average (NFS data, 2009). If you take an average weaning weight of 32kg, then, even given the marginally lower growth rate of the Belclare cross ewes, they still wean an extra 11.2kg of lamb or deliver a 28pc increase in the weight of lamb weaned per ewe.
Even obtaining one third of this difference would provide significant gains on the average Irish sheep farm.