Variably sized clumps of light blue mucus (arrow) are seen in amongst many neutrophils in this peritoneal fluid from a dog with a ruptured mucocele. The mucus is compatible with “white” bile. The total bilirubin concentration was not increased compared to that in peripheral blood. Mucus can also be seen with mucin-producing tumors, e.g. adenocarcinoma, myxosarcoma.
