Preparation for lambing

NADIS disease bulletins are written specifically for farmers, to increase awareness of prevalent conditions and promote disease prevention and control, in order to benefit animal health and welfare. Farmers are advised to discuss their individual farm circumstances with their veterinary surgeon.

January 2004

By Neil Sargison BA VetMB DSHP FRCVS

NADIS Sheep Disease Focus

Preparation for lambing

The past decade has seen a substantial reduction in labour inputs to UK sheep flocks. Despite this constraint, careful preparation for lambing is paramount to protect of the welfare of pregnant and lambing ewes and their newborn lambs. Selection for ease of lambing is an important long-term component of such preparation. 

While selection for “easy care” through the identification and culling of ewes which require assistance at lambing is difficult to achieve within the stratified system of UK sheep production, replacement ewes should be selected on the basis of their pelvic conformation and terminal sires for ease of lambing. 

Lambing should be seen as the critical time when the benefits of preparation throughout the year are realised. The incidence and severity of many lambing problems can be avoided by planned nutritional management of the pregnant ewe. Undernutrition can result in poor lamb survival associated with low birthweights and poor milk production, while overnutrition is wasteful and can result in dystocia. 

During late pregnancy, nutritional adequacy can be reliably determined by blood sampling about 10 ewes and measuring concentrations of urea nitrogen, albumin and 3-hydroxybutyrate, which reflect short and long-term protein, and energy status respectively and enable appropriate adjustment of the diet.

Separation of ewes into different groups on the basis of ultrasound scanning results, ram harness marks, and body condition score can also serve to ensure adequate nutrition during late pregnancy and avoid wasteful overfeeding of late-lambing or single-bearing animals. 

Furthermore, scanning data should be used to ensure that those animals likely to require assistance at lambing (usually twin and triplet-bearing ewes) are separately managed, enabling less time to be devoted to the lower risk groups.

Careful shepherding and selection of lambing paddocks is required to minimise disturbance of lambing ewes thus enabling the establishment of a good ewe-lamb bond and enhancing the survival of newborn lambs. 

Whenever possible, steep and exposed fields should be avoided. Lambing fields should not be too large and water sources not too far apart. When unsuitable lambing paddocks must be used, they should be reserved for single-bearing adult ewes.

Despite long term planning, the need for careful skilled assistance of some lambing ewes is inevitable. 

A clear plan is required to avoid suffering in ewes which cannot be lambed. This should include guidelines about when to seek veterinary assistance, or provision for the immediate humane destruction of distressed animals.

Lambing equipment should be prepared in advance:

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  arm length disposable gloves
  
  
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  obstetric lubricant
  
  
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  a head rope, noose or lambing aid
  
  
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  antiseptic solution
  
  
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  antibiotics, clean needles and syringes

Provision should be made for the management of those diseases which occur annually in most flocks around lambing. 

Clear guidelines should be established about when to seek veterinary assistance and to ensure prompt and humane destruction to prevent further suffering when treatment is unsuccessful or uneconomic.

The list of essential supplies includes:

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  calcium borogluconate injection for the treatment of hypocalcaemia
  
  
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  antibiotics for the treatment of mastitis and metritis
  
  
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  plastic retainers or harnesses, local anaesthetic, clean obstetric tape and needles for the management of vaginal and uterine prolapse
  
  
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  energy supplements for the treatment of pregnancy toxaemia

Preparation for lambing should also be aimed at prevention and management of disease in newborn lambs. The fundamental requirements are:

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  sufficient skilled assistants to monitor all neonatal lambs, to detect and investigate disease and instigate early treatment
  
  
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  good access to lambing pens and good lighting
  
  
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  a compact lambing period to maximise the use of labour and minimise the potential for build-up of disease in the lambing environment. This strategy depends on correct feeding of ewes and rams pre-mating and a good sound ram:ewe ratio
  
  
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  strict hygiene of lambing accommodation. In the case of housed ewes, it is important that both the lambing courts and individual pens are kept clean, to minimise contamination of ewes’ fleeces and udders. Buildings should be well ventilated and drained. Individual pens should be well-lit, easily accessible and cleaned between occupants. Hoggs and long-tailed ewes should be dagged prior to entering lambing accommodation.
  
  
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  the stocking rate of housed lambing accommodation should not exceed one ewe per 1.1 m2 and the area of individual pens should be at least 3.0 m2. Provision of one individual pen per 8 housed ewes is recommended
  
  
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  dip all lambs’ navels in strong iodine solution at birth (and again four hours later). Dipping is preferable to spraying with oxytetracycline
  
  
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  ensure that all lambs receive adequate colostrum within the first 4 hours of life. If in doubt, administer 50 ml/kg of colostrum or colostrum substitute by stomach tube
  
  
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  hot water and a full clean lambing kit should be easily available
  
  
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  check all penned lambs regularly for signs of brightness and full stomachs. Navels should be brittle by 36 hours-old

Despite careful preventive management, the occurrence of disease in newborn lambs is inevitable.  Provision should be made for the treatment of the common problems and specific diseases which occur in the flock:

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  stomach tubes, colostrum, a warming box, glucose injection, syringes and needles for the treatment of starvation and hypothermia
  
  
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  clips or small syringes and needles for subconjunctival injections to correct entropion
  
  
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  oral antibiotics for watery mouth prevention
  
  
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  injectable antibiotics for the treatment of neonatal bacteraemias

A protocol should be established to ensure that each of these problems is correctly managed. Your vet can advise you about the most appropriate regime for your flock.   Vets are only permitted to prescribe pharmaceutical products to “animals under their care”, so may be unwilling to issue antibiotics for use in flocks which they have not recently visited.

Routine management tools such as ear tags, castration rings and pliers and wormer to control the periparturient rise in faecal egg counts of ewes should also be prepared in advance of lambing.

• While every effort is made to ensure that the content of this forecast is accurate at the time of publication, NADIS cannot accept responsibility for errors or omissions. All information is general and will need to be adapted in the light of individual farm circumstances in consultation with your veterinary surgeon.

Copyright © NADIS 2002