Abstract

Aloe ferox is used by communal farmers in the Eastern Cape in the treatment of gastrointestinal parasites in goats. In this study, the leaf aqueous extract of A. feroxwas evaluated for its potential toxicity, using the acute, sub-acute and chronic toxicity models in rats. The plant extract was administered by oral route at doses ranging from 200 to 1600 mg/kg. No deaths were recorded in acute toxicity. In sub-acute toxicity, the extract caused mortalities; 75% at 800 mg/kg and 100% at 1600 mg/kg dose. The plant extract also caused a significant (P<0.05) increase in levels of platelets, neutrophils and monocytes. Biochemical results showed a significant (P<0.05) increase in alkaline phosphatase (ALP) and alanine amino transferase (ALT), as well as a decrease in albumin levels. In chronic toxicity, there was a significant (P<0.05) increase in platelets, lymphocytes and basophils. There was also a significant (P<0.05) increase in urea, bilirubin and globulin levels, and a significant (P<0.05) decrease in albumin levels. Body weight reduction and lesions on kidneys, lungs, hearts and spleen were observed. The results show that the plant is toxic at doses of 400 mg/kg and above.

Key words: Aloe ferox, blood, extract, organs, toxicity