In addition to generalized icterus, enlargement of the liver and severe photosensitization, signal grass (Brachiaria decumbens) toxicity also caused ruminal stasis and a decreased rumen pH in sheep. Ruminal stasis, which occurred within 3 weeks of grazing on this grass, may be the effect of the toxin produced in the rumen rather than a sequele of a decreased rumen pH. Animals were anorexic and the volume of their rumen content was very much reduced.