Conditions when likely to occur:
Late pregnant cows in last six weeks of pregnancy grazing dry poor quality pasture (<1,000–1,500kg DM/ha), stubbles or green pasture less than 800kg DM/ha. Either cows over fat score 3 or light cows on very poor pasture.
Clinical signs: pregnancy, animal recumbent, and neurological signs such as staggering, aggression, delirium. Often associated disease process.
Management strategy to prevent disease:
Avoid grazing cows on pasture where rapid weight loss is likely in late pregnancy, or supplement to avoid rapid weight loss.
Avoid getting cows too fat (>FS3.5–4) or too thin (<FS2–2.5) in late pregnancy.