Related Experiment Videos
Perinatal lamb mortality--its investigation, causes and control.
Journal of the South African Veterinary Association
|June 1, 1991
Summary
Investigating perinatal lamb loss requires precise methods like ultrasonic litter size determination. Birth stress and the starvation-mismothering-exposure (SME) complex are primary causes, necessitating improved flock management and breeding for resilience.
Area of Science:
- Veterinary Science
- Animal Husbandry
- Perinatal Mortality Research
Background:
- Perinatal loss in grazing sheep flocks significantly impacts productivity.
- Accurate investigation methods are crucial for understanding mortality causes.
- Existing methods vary in precision and cost-effectiveness.
Purpose of the Study:
- To review and evaluate methods for investigating perinatal loss in sheep.
- To identify the primary causes and contributing factors of lamb mortality.
- To propose improved control and management strategies.
Main Methods:
- Review of existing investigation techniques, including the 'wet-dry' method and ultrasonic litter size determination.
- Veterinary field investigation involving lamb autopsy, historical data review (nutrition, disease, husbandry), and environmental assessment.
- Pathological and pathophysiological analysis of birth stress and the starvation-mismothering-exposure (SME) complex.
Main Results:
- The 'wet-dry' method is simple for minimal prevalence; ultrasonic determination is most precise.
- Pathological processes identified in >95% of deaths; specific causes in ~75%.
- Birth stress and the SME complex account for at least 80% of mortality, with birth injury to the CNS being a key indicator.
Conclusions:
- Birth stress is a major factor in perinatal lamb mortality.
- Heritable traits (birth mass, maternal dimensions, behavior) and environmental factors influence mortality.
- Control requires selection for maternal ability, optimized nutrition, disease control, shelter, and husbandry that supports parent-offspring behavior.