Lambing

• Traditional causes of lamb deaths

  • Dystocia
  • Starvation-exposure
  • Miss-adventure
  • Disease
  • Mineral deficiency
  • Abnormality
  • Predation
  • Unknown cause
• Lamb death rates across NZ farms are between 5 and 25%
• Factors leading to higher lamb death rates

  • Farms with high lambing %'s
  • Farms that are more exposed
  • Sudden and extreme weather events
• Dystocia


  Death due to either pelvic opening disproportional to size of the lamb, incorrect fetal presentation at birth, fetal entanglement with multiples, or weak dam which displays a prolonged weakened birth process
• Starvation-exposure


  Death due to either exposure (lamb cannot physically produce enough body heat to survive) or starvation (lamb not getting enough milk)
• Dystocia and starvation/exposure can both contribute to lamb death, as a dystocia damaged lamb can also starve to death
• Causes of death in single, twin, and triplet lambs (as % of total deaths)

  • Prenatal death
  • Dystocia
  • Starvation-exposure
  • Infections
  • Abnormal lambs
  • Misadventure
  • Unknown
  • Ewe death
• Reducing losses due to Dystocia

  1. Controlled feeding (not overfeed single-bearing ewes, not under feed multiples)

  2. Sire selection (birth weight, shape)

  3. Intervention/monitoring
• Diagnosing Dystocia


  • Swollen head (or britch if backwards)
  • Jelly like substance (oedema)
  • Lungs not inflated
  • Foot pads still intact
  • Empty stomach/rumen
  • Rupture/haemorrhage of the liver
• Reducing losses due to starvation exposure

  1. Provide shelter

  2. Have suitable lambing paddocks

  3. Adequate feeding levels in pregnancy

  4. Good pasture covers during the lambing period

  5. Ewes in good body condition

  6. Check dams teats before breeding

  7. Time lambing/spread of lambing

  8. Pregnancy shearing

  9. Reduce chance of ewe and lamb separating
• Diagnosing starvation-exposure


  • Lungs are inflated
  • Foot pads are eroded
  • May, or may not, have food stomach/rumen
  • No brown adipose tissue around kidney and heart
  • Or at least some degradation of these fat reserves
• There is no right or wrong answer on whether lambing beats should be done, it depends on the management system and farm characteristics
• What can be done to maximise lamb survival?

  • Plan timing of lambing to minimize poor weather
  • Ensure ewes are fed adequately in mid- to late-pregnancy and at lambing/lactation
  • Ensure ewes are in good body condition at in late pregnancy and at lambing
  • Ensure ewes have had all relevant vaccinations and that their mineral status OK
  • Split singletons and multiples
  • Selection of ewes based on mothering ability
  • Ram/ewe selection based on lamb survival traits
  • Paddock selection (slope/shelter) and avoidance of risk areas
  • Shear ewes in pregnancy
  • Consider using alternative herbages
  • Cull ewes with poor udders
• An ideal lambing paddock would have: Pasture cover of 1200 – 1400 kgDM/ha, ewes set stocked at a rate where feed demand equals pasture growth, a gentle slope, shelter, and avoid swamps, tomos, creeks, dams