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Australian veterinary journal
Mar 15, 2025;

Periparturient mortality in merino ewes in Australia: Incidence, impact and the path to mitigation strategies.

B Kirk, T Clune, E de Looff, J Jones, S Barber, D McGill, L Rowlands, S McGrath, J Kelly, A Whale, C Jacobson, E Glanville
Author Information
  1. B Kirk: Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Australia. ORCID
  2. T Clune: Murdoch University, Centre for Animal Production and Health, Food Futures Institute, Murdoch University, Murdoch, Australia.
  3. E de Looff: Pinion Advisory, Dowsing Point, Australia.
  4. J Jones: Pinion Advisory, Dowsing Point, Australia.
  5. S Barber: Melbourne Veterinary School, Faculty of Science, University of Melbourne, Melbourne, Australia.
  6. D McGill: Central Queensland University, Norman Gardens, Australia.
  7. L Rowlands: Pinion Advisory, Dowsing Point, Australia.
  8. S McGrath: Millicent Veterinary Clinic, Millicent, Australia.
  9. J Kelly: Animal Health and Nutrition Consulting, Coonamble, Australia.
  10. A Whale: Livestock Logic, Apiam Animal Health, Hamilton, Australia.
  11. C Jacobson: Murdoch University, Centre for Animal Production and Health, Food Futures Institute, Murdoch University, Murdoch, Australia.
  12. E Glanville: Well Stock Consulting, Bathurst, Australia.
PMID: 40088148 DOI: 10.1111/avj.13430

Abstract

Managing breeding ewe mortality is a priority for the Australian sheep industry. The periparturient period carries the highest risk of mortality, but the incidence and causes in Merino ewes are not well characterised. Here, we outline the reported incidence of annual and periparturient mortality for Australian Merino ewes, causes and risk factors for ewe mortality and current recommendations for managing periparturient ewes and gaps in the literature. The mean incidence of periparturient mortality reported in Merino ewes ranges from 0.3% to 11.4%. However, there are challenges with reporting mortality figures in extensive production systems due to the nature of record keeping and farm characteristics. Studies reporting causes of periparturient mortality indicate that these are typically multifactorial, with metabolic disease and dystocia likely to be important. Identifying potential mitigation strategies has the potential to improve productivity, profitability and welfare on Australian farms.

Keywords

dystocia lambing period metabolic disease sheep survival

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Grants

  1. /University of Melbourne
  2. /Meat and Livestock Australia
  3. /Australian Wool Innovation
Journal Article Review

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