knot rot

例句：

1. 1. The farmer noticed a knot rot on his cow's leg.
   农夫注意到他的牛腿上有一个结瘤。
2. 2.The veterinarian diagnosed the knot rot and prescribed medication.
   兽医诊断出结瘤并开处方药。
3. 3.The patient was advised to remove the knot rot for proper healing.
   病人被建议移除结瘤以便适当愈合。