Bloat is a potentially fatal digestive emergency in cattle caused by accumulation of gas in the rumen, and pasture management to prevent it is a critical welfare responsibility on farms with legume-rich pastures.
Bloat causes rapidly escalating welfare suffering — distension of the rumen causes severe abdominal pain as pressure builds, and compression of the diaphragm causes increasing respiratory distress. Death from bloat is by asphyxiation and cardiovascular failure. The rapid progression from initial signs to life-threatening severity means that monitoring cattle on at-risk pastures during the highest-risk periods (2-4 hours after turnout onto legume-rich fields in wet weather) is critical. Farmers who leave cattle unobserved on bloat-risk pastures risk significant preventable welfare emergencies. Proactive management — drenching with anti-foaming agents before turnout, limiting time on high-risk pastures, and maintaining dried grass access — reduces incidence substantially.