Lamb losses are detrimental to farm profits. Most occur during pregnancy, or in the first week of life and there are common culprits. The reasons for loss should be monitored and recorded, to target reductions up to the point of sale.
For future lambing success, all lamb losses must be recorded, including ‘invisible’ losses; meaning reabsorption of the pregnancy or aborted lambs. This accounts for about a third of all losses, this is too significant a number not to be included.
Farmers should make a note of six key records throughout pregnancy and up to rearing:
1) Total number of ewes tupped.
2) Number of lambs scanned during pregnancy.
3) Number of lambs born alive. Compare this to figure 2 to determine how many lambs are lost due to reabsorption or abortion.
4) Number of lambs born dead. This could indicate infectious abortion or nutritional deficiency.
5) Record the number of lambs turned out. Compare this with figure 3. If lambs are born alive but don’t survive, hygiene issues or problems with colostrum may be an issue.
6) Record the number of lambs weaned/sold. Compare this with figure 5. High mortality in the first few months can often be attributed to inadequate control of worms or other disease.
Be sure to compare your own records year on year and then against the national average:
Source: Sheep BRP Manual 14
Prevention and protection
The records you keep may highlight repeat problems at lambing time. First, get to know what the most common problems are and how to handle them.
Infectious abortion is responsible for 86% of all sheep abortions. Within this statistic the two most common offenders are:
- Enzootic abortion (52%): A bacterial infection, so do not keep infected sheep or their lambs for replacements.
- Toxoplasmosis (25%): Parasitic infection transmitted by cats, so keep them away from feed.
To protect ewes from these common causes of abortion, vaccinate them at least four weeks before tupping.
Observe ewes closely for any signs of peri-natal problems. The more you know about the types of conditions you might have to deal with, the better.
Three of the most common complaints are:
- Twin Lamb Disease
Most ewes should lamb within four hours of the onset of labour and without difficulty. You should try not to intervene, but quietly look out for signs of a problem. This could be:
- Mixed up twins and triplets
- Dead lambs
- Deformed lambs
The weather plays an important part in lamb losses, so where you rear lambs is key:
- Protection from poor weather
- Easier to tag and collect data
- Fostering easier if required
- Pasture is given a chance to recover and grow
- Reduced feed and labour costs
- Less interference can mean reduced stress in the sheep
- Reduced stocking density can lead to reduced risk of infectious disease
Your sheep farming system and condition of ewes will determine which methods are most likely to bring you reduced losses. Certainly, a robust health plan for ewes, good nutrition and a vaccination programme will reinforce your efforts.
POM-VPS For further information please see the product’s SPC or contact Zoetis UK Limited, Walton Oaks, Dorking Road, Tadworth, Surrey KT20 7NS. www.zoetis.co.uk. Customer Support: 0845 300 8034. Use medicines responsibly (www.noah.co.uk/responsible). Date of preparation: December 2016.