Single sire mating delivers the advantage of matching ewes and rams with desirable traits and being able to track progeny easily back to the sire. However it does come with a risk of fertility issues, so practices should be put in place to limit the potential effect.
Raddling rams will identify higher than normal repeat rates and sound alarm bells. But this practice alone can delay breeding for two cycles in some sheep.
Therefore the preferred option for many is to switch rams between groups after the first cycle so that if there are ram fertility issues ewes will have been bred with another ram and issues can still be identified through raddling, highlighting high repeat rates.
Raddling rams regularly should be high on the agenda this year given the high cost of concentrates. Changing the raddle colour on a weekly basis allows you to implement precise feeding programmes and avoid unnecessary supplementation.
For those a few weeks away from breeding, offering rams a small volume of concentrates and preferably getting them accustomed to eating in a temporary pen constructed from sheep hurdles may save a lot of work.
This does not always work where ewes are in heat, but it can be very worthwhile where handling facilities are poor.
Issues can still occur where rams are being run in a group with ewes. The usual issue is a dominant ram experiencing fertility issues preventing other rams from mating with ewes.
Care should also be taken with ram lambs to actually monitor rams serving ewes and to be on guard for false mounts.
This is sometimes linked to overfed or overweight rams suffering with feet issues such as bad back pasterns. In such cases rams may mount and raddle ewes but not actually serve ewes due to pain associated with the process.
The Department of Agriculture Regional Veterinary lab reports indicate that worm burdens, septicaemia / bacteraemia, pneumonia and enteritis (linked to clostridial disease) are the most prevalent causes of mortality in flocks in September and October.
Worm burdens are often underestimated at this stage of the year due to a perceived lower threat, when in reality the sward burden is often at its highest level across the year.
Clostridial disease vaccination will reduce the risk. In flocks where pasteurellosis is deemed a risk then the choice of vaccine should take this into account.
Predisposing factors include any stressor that puts the animal’s immune system under pressure such as concurrent health issues, exposure to inclement weather, handling and transportation including overcrowding.
Sheep welfare scheme tasks
A number of measures are due to conclude before the end of September. Two Dag scores must be carried out as part of the flystrike control option from 1 June to 30 September.
Two faecal egg counts must also be carried out as part of the parasite control option before 30 September in lowland flocks and one in hill flocks.
The common measure of mineral supplementation for at least 60 days post-breeding is also timely. Post-breeding is classed as when rams are joined to ewes, but supplementation can start before this.
One or a combination of products can be used as long as minerals are administered in line with product guidelines.