The aim of lambing is to have a healthy ewe give birth to live lambs that are up and sucking as soon as possible, ideally without much assistance.
The biggest risk period to a lamb is the first 48 hours, closely followed by the next two weeks. If you can manage to keep your lambs alive up to 15 days their survival prospects increase significantly. It is important to prepare for this well in advance, making sure the ewe is healthy and in good body condition for giving birth.
Correct ewe nutrition is perhaps the single most influential factor behind periparturient losses – in terms of both lambs and adult sheep. Correct feeding optimises ewe health, resulting in higher lamb numbers and weights, and improving colostrum quality and yield. This in turn will optimise lambs’ growth and performance.
The best way to keep track of your feeding and whether it is suitable is by monitoring the ewe’s body condition score (BCS). This should be done regularly to keep track of any changes and adjust feeding as necessary.
Forage should be the largest proportion of the diet, either fresh grass or conserved forages such as hay, silage or straw. If you can have it analysed this gives you a guide to how much should be fed and whether any concentrates are required.
Pregnant ewes require increased energy levels in late pregnancy (50% more if carrying twins). In late pregnancy a ewe’s feed intake can drop so concentrates may be required as these have a high energy density. It is important to avoid giving more than 0.5kg per feed as the resultant acidosis would disrupt digestion, if necessary it should be fed twice daily.
Protein content is also essential. A good concentrate will contain 18-20% crude protein (CP). Whilst not individually listed, it is the quality, or DUP component (dietary undegradable protein) of this protein which is key. This can be inferred by looking at the ingredients: look for high levels (10%) of soya, rapeseed etc. Do not be fooled by the inclusion of soya hulls – these are a fibre source and are low in protein!
Don’t forget that getting the diet right will only succeed if ALL the ewes are able to eat it, so allow enough space: 6” per ewe for ad lib feeding, 18” for restricted concentrate feeding. This should also help reduce the incidence of prolapses.
Scanning ewes enables grouping and feeding of ewes according to the number of lambs carried, and therefore their likely requirements. Close monitoring of (and response to) condition score is also essential, whether scanning or not.
Ewes can be blood-sampled 3-4 weeks before lambing in order to monitor the diet: if deficiencies are detected, the appropriate dietary changes can be calculated.
It is now too late to vaccinate, but it isn’t too late to protect the rest of your flock should abortions occur, and to harvest information for action next year if appropriate. Isolate any aborting ewes and disinfect the area. If >2% abort, investigation is indicated: ideally submit fresh lambs and placenta for laboratory analysis, but if this is not possible, aborting ewes should be retained, as they can be blood-sampled at a later date. Make sure any blood sampling of ewes is carried out within 3 months of the abortion as the accuracy reduces with longer periods.
Colostrum is Gold: not only does it contain maternal antibodies, which are a lamb’s major protection against disease for the first few weeks of life, but it is high in energy, vitamins and minerals. Lambs are born with no viable immune system so without the influx of antibodies from the colostrum they are open to every infection.
The Three Qs Of Colostrum
The three Q’s of colostrum should be followed at all times:
Quality – There are many ewe factors which affect this, age, breed, mastitis, nutrition and body condition. Thin ewes produce less colostrum, reasons for thin ewes are nutrition, chronic fluke, chronic lameness, insufficient feedspace, so if you have a high proportion this should be investigated. A well fed ewe produces better quality colostrum. You can measure the quality of colostrum using a refractometer. You also need a good collection technique, as dirty colostrum will have bacteria in it which reduces the quality. If a ewe has mastitis or is painful post lambing she won’t allow her lambs to suck, anti-infammatories can be very useful if you have had a difficult lambing.
Quantity – 210 – 290ml colostrum/Kg bodyweight in the first 24hrs of life gives a lamb the essential levels of natural immunity. The first feed should be within 2 hours of birth. Make sure the ewes are producing colostrum and that the teats are available to the lambs. If there are triplets often the smallest will be pushed out by the older lambs, so monitor them to make sure they are all having enough time to suckle.
Quickly – The first feed should be within 2 hours of birth. After 24-36 hours lambs are incapable of absorbing the colostrum so you lose the benefit it provides them. It is worth taking the time to give the lambs colostrum as this gives them the best start in life.
If you have a ewe with a single lamb it is a good idea to milk her to keep some of her colostrum for any triplets or lambs from ewes with little/no udder development. Colostrum can be stored in a clean container in the fridge for 7 days, or it can be frozen in flat ziplock bags, which means it can be quickly defrosted. However it is worth checking the quality first as there is no point storing poor quality colostrum.
When defrosting colostrum use hot water (not boiling) rather than a microwave as you don’t want to damage the immunoglobulin proteins which are sensitive to high temperatures. Consider buying a BRIX refractometer with a 0-32% scale so you can make more informed decisions about whether to feed, store or discard colostrum.
If you are having large numbers of scouring lambs, or lamb deaths it is possible to measure how successful the colostrum management is. This can be done by blood sampling lambs under a week old to check their passive transfer of IgG antibodies.
Watery mouth arises due to lambs swallowing bacteria from the environment, and diseases such as navel ill, joint ill and E coli diarrhoea can all also be largely avoided by preventing bacterial infection from dirty conditions. With this in mind, Cleanliness is indeed next to Godliness, and is paramount to avoiding disease. Dryness is a factor here, so good drainage and ample bedding are required. A compact lambing period will help reduce disease build-up, and don’t overstock: allow 1.3sq m per ewe and one individual pen per 8 ewes lambed. Good colostrum intake goes a long way to providing protection, as does dressing navels with strong Iodine. Treating every lamb with an oral antibiotic is a poor substitute for getting the management correct. There is a large percentage of E. coli that are resistant to spectinomycin (the active ingredient in spectam) this means that there is a big risk of problems on farms where they rely solely on this. We have had flocks reduce their Spectam use by 60% after following the advice above, which with the red tractor guidelines is a great step in the right direction.
Protection against Clostridial diseases (and possibly also pneumonia) should also be provided, by vaccinating ewes in late pregnancy. Vaccination for these diseases should be given to the ewes 4-6 weeks pre-lambing to allow the antibodies to be produced and included in the colostrum.
Even with the best laid plans, things can go wrong, so make sure you are prepared. Some things to consider:
- Lambing ropes, disposable gloves, lubricant
- Colostrum supply (e.g. frozen surplus ewe colostrum, artificial colostrum), stomach tubes, bottles
- Medicines (antibiotics, anti-inflammatory injection, propylene glycol for twin lamb disease, calcium injection)
- Warming box for hypothermic lambs; also glucose for intra-peritoneal injections if required
Onwards & Upwards
A good start in life goes a long way to finishing quality lambs, but as they grow, clearly there will be other considerations. Gut roundworms, coccidiosis and trace element deficiencies are some examples of potential issues. Their monitoring and management can be achieved with the help of your vet, so remember to phone us if you have any concerns!