The excitement (母豬興奮;如果有在現場用飼料子車餵母豬的經驗就能感受到)produced by the progress of the feeding process often results in clockwise twisting of the stomach (胃) sometimes together with the spleen (脾臟). Once the stomach has twisted, the contents ferment, trapped gas causes the organ to swell and the sow dies rapidly from raised intra-abdominal pressure or shock.
Death can also result from rupture of the spleen and loss of blood into the abdominal cavity.
Torsion of the intestines is most common in growing and finishing pigs and may be spontaneous or occur in association with enteritis. There are a number of predisposing factors. In sows, ossification of the root of the mesentery may give rise to sharp flakes of bone which tear the mesentery and allow torsion to take place, in younger pigs, the adhesions of Glässer's disease may restrict intestinal movement and in finishers on rations containing whey or other carbohydrate-rich liquid, fermentable carbohydrate may reach the caecum, ferment and cause torsion of the whole large intestinal mass around its root.