Scanning of mid season lambing ewes a priority
AS we move into the second week of January the last thing you might be thinking about is scanning the ewe flock. Some farmers may even still have some of last year’s lambs still on the farm!
However, for mid-season lambing ewes, that is ewes lambing from the 10th -15th March onwards, getting these ewes scanned and fed according to the results should be a priority from now on.
After such a dry summer and autumn with plenty of grass ewes would have been in good condition at the time of ram turnout and hopefully they are still in good condition and we would be hoping for good results from the scanning.
While scanning may have started on some farms already, the majority of farmers operating mid-season lambing flocks will begin scanning in the coming weeks between now and the end of the month with hill flocks starting to scan from the end of January to mid-February.
In addition, as part of the sheep welfare scheme, scanning ewes is a requirement for those farmers who chose the option of management of pregnant ewes. While it may be an option you chose as part of the scheme, scanning should really be used as one of your management tools on the farm to allow you to plan your feeding programme for the flock between now and the beginning of lambing with an overall objective of maximising the number of live lambs born on the farm which will ultimately increase farm output.
For best results scanning ewes should take place between 70 and 90 days in lamb. Scanning ewes that are greater than 90 days in lamb will make it more difficult for the scanner to identify how many lambs the ewe is carrying.
On the other hand, scanning ewes less than 40 days in lamb (40 days since the ram was removed from the flock) should be avoided, as pregnant ewes may be undetectable by the scanner and therefore may be considered empty.
Identifying empty ewes will allow for them to be culled or grouped separately keeping valuable feed supplies for pregnant ewes only. Knowing how many lambs each ewe is carrying is the real benefit. This will allow you to make important management decisions on ewe nutrition.
Ewe nutrition in late pregnancy underpins her milking performance and the growth rates of her lamb(s) post lambing. Ewes can also be batched according to litter size for ease of management and feeding.
Scanning can also be financially beneficial as, during late-pregnancy on most sheep farms, expensive concentrates are fed to ewes. Typically, concentrates are fed as a supplement to grass silage and in some cases grass.
If the quality of the grass silage – or grass – is very good then, feeding a single bearing ewe the same amount of concentrates as a twin bearing ewe is economically unjustifiable given the return.
Furthermore – by knowing the litter size of each ewe – problems at lambing time associated with under or overfeeding can be avoided and lambing losses incurred may be minimised.
As I mentioned already, for farmers who selected the scanning task as part of the Sheep Welfare Scheme, this must be conducted between 70 and 100 days post ram turnout. Using the scanning results ewes should be divided on the basis of predicted litter size and fed accordingly. A receipt from the scanner with the number of ewes specified must be retained in your records. Details of the scanning results will need to be recorded in the record book along with details of the supplementation regime.
In summary, to ensure ewes are scanned at the optimal dates you should contact your scanner in time and book early for the most accurate results. Plan your feeding strategy based the scanning results and the expected litter size and ewe requirements and ensure all records are up to date if scanning is one of the options chosen as part of the Sheep Welfare Scheme.
If you have never scanned your flock in previous years then maybe 2019 might be the year to start!