Ethanol extract of Amaranthus spinosus
leaf (EEAL) was administered orally to growing pigs to determine its effects on the haematological characteristics-packed cell volume (PCV) red blood cell (RBC) and white blood cell (WBC) counts, and haemoglobin (HB) concentration. Eighteen growing pigs were randomly allotted to two treatments with each treatment replicated thrice. Pigs in treatment 1 were administered with EEAL. Treatment 2 served as control receiving no treatment. Results showed that there were significant (P<0.05) reduction in the PCV, RBC and Hb of the pigs administered with EEAL seven days post treatment and their weight gains significantly (P<0.05) improved. Amaranthus spinosus , although an active vermifuge should be used in animals with adequate precaution to avoid any probable toxic effects.