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Instrumentation of Near-term Fetal Sheep for Multivariate Chronic Non-anesthetized Recordings
Published on: October 25, 2015
STAGGERS IN SHEEP IN PATAGONIA.
1Department of Animal Pathology of The Rockefeller Institute for Medical Research, Princeton, N. J.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Staggers, a non-infectious animal disorder, is caused by consuming Pampa grass (Poa argentina). This grass induces symptoms like weakness and paralysis, but affected animals often recover with dietary changes.
Area of Science:
- Veterinary Medicine
- Animal Science
- Toxicology
Background:
- Staggers is a recognized non-infectious disorder affecting livestock.
- Clinical signs include motor disturbances, visual impairment, and conjunctivitis.
- Postmortem examinations reveal no characteristic lesions.
Purpose of the Study:
- To identify the cause of staggers.
- To investigate the toxic properties of Pampa grass (Poa argentina).
- To understand the disease progression and recovery patterns.
Main Methods:
- Field observations and laboratory experiments were conducted.
- Susceptible sheep were fed Pampa grass under controlled conditions.
- Experimental feeding duration varied to assess symptom onset.
Main Results:
- Feeding Pampa grass to sheep reliably produced staggers.
- Symptom development occurred within 2 to 21 days, averaging 10 days.
- The grass is toxic year-round, including young green and flowering stages.
Conclusions:
- Pampa grass (Poa argentina) is identified as the causative agent of staggers.
- Most affected animals recover spontaneously or with dietary adjustments.
- Long-term pasture exposure may lead to tolerance in older animals.
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