To evaluate the toxicity of different concentrations of pods of Stryphnodendron fissuratum to pregnant cows, the pods of this tree were grounded, mixed in a commercial food and given to eight pregnant cows in total doses of 6.5g/kg, 7.5g/kg, 9g/kg and 10g/kg. The animals that received doses of 6.5g/kg delivered normal calves and those that received 7.5g/kg delivered weak calves that did not survive. Doses of 9g/kg resulted in the birth of an immature calf and another with congenital bilateral distichiasis, corneal opacity, and microphthalmia. Both cows that ingested 10g/kg died, and one of these aborted before death. In the dead cows, the gross and histological lesions of the digestive system and liver were similar to those previously described in S. fissuratum poisoning. No significant lesions were observed in the calves and in the aborted fetus. The phytochemical analysis of methanol extracts from pods of S. fissuratum revealed the presence of soluble tannins, proanthocyanidins, leucoanthocyanidins and the triterpenoid saponin β-amyrin. Triterpenoid saponins had been associated with the toxicity of Stryphnodendron spp. and Enterolobium spp., which cause clinical signs similar to those observed in the poisoning by S. fissuratum. The results presented herein confirmed the toxicity of S. fissuratum to bovines. However, the abortive effects of this plant was not confirmed; thus because the abortion and neonatal deaths could be due to the toxicity of the pods to the cows. New research should be done to demonstrate if S. fissuratum is a cause of malformations similar to those observed in one of the calves born from the treated cows.
Poisonous plants; Stryphnodendron fissuratum; Mimosoideae; abortion; fetal malformation; plant poisoning; cattle
