bloat, excessive accumulation of gases in the rumen, the first stomach of a cud-chewing animal. Bloat is probably formed to a large extent by bacterial action. It occurs in all ruminants, but is most common in cattle; it appears typically in animals that graze on newly developed, highly productive, lush green pastures, especially during a wet summer on clover-dominant pastures. Bloat can result from excess frothiness of the ruminal ingesta or loss of tone and motility of the rumen. Both of these conditions will prevent the normal eructation process. Treatment consists of passing a tube to the stomach or of reducing the foam formation by oral administration of mineral or vegetable oils. Prevention is attempted by carefully controlled management practices, administration of antibiotics, and the use of nontoxic oils.