Experiments showed that the clinical and pathological pictures were essentially the same, but the buffalo was at least twice more resistant than the bovine to the toxic effect of Arrabidaea bilabiata (Sprague) Sandw. It was also shown that the young leaves are twice (October, end of the dry season) or one and a half (May, end of the rainy season) more toxic than the mature leaves, and that the plant is more toxic in October. These data indicate that the smaller incidence of poisoning by plants of the group that causes sudden death in buffaloes in the Amazon Region is, in part, due to the greater resistance of this animal species to the toxic action of the plant. Also important seems to be the coincidence of the preferential habitat of the buffalo (flooded areas) with the habitat of A. bilabiata, less toxic than Palicourea marcgravii St.Hil. which is a plant of the non-flooded areas, the preferential habitat of cattle.
Plant poisoning; Arrabidaea bilabiata; Bignoniaceae; toxicity; buffalo; cattle
