Features
Artificial Rearing of Lambs
by Dr Colin Macaldowie
In most flocks there will always be spare lambs that cannot be reared by their natural mother which need to be reared artificially. It is important that the farmer or shepherd can identify these quickly and that they have the necessary training to carry out these techniques successfully.
In most cases fostering is preferable to artificial rearing. However, if a lamb cannot be raised by its natural mother or fostered onto another ewe, then it will have to be reared artificially. Rearing lambs in this way requires the very highest level of stockmanship and dedication if it is to be successful. This article hopes to highlight some of the basic principals of successful artificially lamb rearing.
Feeding the Newborn Lamb
In general a stomach tube should always be used when feeding newborn lambs. A bottle and teat may be suitable for feeding the strong orphan lamb but can be lethal when feeding the weaker newborn lamb, because milk can enter the trachea (windpipe) and lead to inhalation pneumonia. However, it should be noted that it is dangerous to feed semiconscious or unconscious lambs (normally hypothermic) with a stomach tube. If a lamb can lie in sternal recumbency (on its front), and hold up its head it is safe to feed it by stomach tube. If not it must be treated for hypothermia (see Moredun Foundation News sheet Vol. 1, No. 1 ’Detection and Treatment of Hypothermia in Newborn Lambs’ & Moredun Foundation News sheet Vol. 2, No. 14 ‘Maximizing Lamb Survival’).
If a lamb is not sucking from a ewe it should be fed at least three times daily, e.g. 7am., 3pm. and 11pm at the following dose rates;
- Large lamb (average single) - about 5 kg; 200 ml each feed.
- Medium lamb (average twin)- about 3.5 kg; 150 ml each feed.
- Small lamb (average triplet) - about 2.5 kg; 100 ml each feed.
If it is practical, feed lambs more often. The quantity per feed should be reduced proportionally. As a rule of thumb approximately 40-50ml per kg bodyweight should be fed three times daily
Ewe colostrum is the best food for the newborn lamb. If possible accumulate a store of ewe colostrum by milking ewes with a plentiful supply, e.g. ewes with single lambs. You may wish to put one or two ewes with a history of being prolific milkers to the ram earlier to ensure that colostrum can be collected in advance of the main lambing. Colostrum can be stored in the deep freeze in small containers and gradually defrosted in a bucket of warm water when required. Never defrost frozen colostrum by boiling in a saucepan or by using a microwave as any overheating will destroy the protective protein antibodies. Do not refreeze colostrum
The best substitute for ewe colostrum is cow colostrum however cow colostrum does not contain the same protective antibodies found in ewe colostrum. Milk replacer is an acceptable food for the lamb aged more than 24 hours but should not be regarded as a substitute for colostrum. Glucose/electrolyte solution is used for feeding lambs that have enteritis or watery mouth. In an emergency it can be used to feed any hungry lamb. Use one of the proprietary calf scour mixtures, but add powdered glucose to bring the concentration of glucose in the feeding solution to 10 per cent, i.e. 100 grams per litre.
It is vitally important that clean lamb stomach tubes and 60 ml feeding syringes are used to feed young lambs. Syringes and tubes should be rinsed after each lamb and sterilised at least once daily to prevent disease being passed from lamb to lamb.
Management of the Artificially Reared Lamb
If you decide to artificially rear a lamb, it is still ideal to leave the lamb with the ewe for the first 24 hours, and supplement the whole litter by stomach tube. Ensure that all the lambs receive plenty of colostrum. At about 24 hours of age lift the lamb that you have selected to rear artificially - preferably the strongest - and transfer it to an individual box warmed by a heater or infrared lamp. Feed the lamb milk replacer by bottle three times daily and give oral antibiotic twice daily (consult your veterinary surgeon about this).
At 72 hours of age transfer the lamb to the artificial rearing pen provided that it is strong, is sucking well and is showing no signs of disease. Ideally, lambs should be reared in groups of up to twelve. Never introduce a sick lamb to a group of lambs - it will probably infect the others. All lambs, irrespective of source or age, which are destined for artificial rearing, should undergo this 48-hour 'quarantine' period before being introduced to the artificial rearing pen.
When rearing lambs artificially, always use a good quality ewe milk replacer. These are usually made up by mixing 200 grams of milk powder with water, hot or cold depending to the manufacturer’s instructions, to produce one litre of milk. Check that the measure used to dispense the powder gives the correct amount. If too little powder is used, the lambs may starve; if too much, the lambs may become dehydrated and may also scour. If a lamb refuses to suck much milk, feed it by stomach tube - do not let it starve.
Finally, do not wean lambs too early; otherwise a serious check in growth and intestinal problems will result. Try not to wean before 30 days of age or at a body weight of less than 10 kg. Always ensure that lambs are taking solid food before weaning.
Health of the Artificially Reared Lamb
The relatively close confinement of lambs housed in groups in an artificial rearing system inevitably increases the risk of infectious diseases such as enteritis and eye infections. Following these guidelines can reduce the incidence of these problems:
(1) Give oral antibiotic for the first three days of life (take advice from your veterinary surgeon and remember that this may not be possible under organic management).
(2) All lambs must undergo 48 hours of quarantine before introduction into the system.
(3) Never introduce a sick lamb.
(4) Watch the lambs closely and isolate and treat any sick lamb.
(5) Clean and sterilise the feeding equipment daily.
(6) Give the lambs plenty of space and fresh air while preventing draughts.
(7) Avoid using infrared lamps to stop lambs from crowding together under the heat.
Footnote: this article first appeared in the Sheep Farmer magazine and is reproduced with their permission