Abstract: Twelve locating West African Dwarf (WAD) ewes averaging 14 kg in weight and age between 2-3 years were used in 12-weeks study to determine the partial daily milk yield (PDM), haematological and serum biochemical parameters of ewes fed the ethnoveterinary and ethnomedical plant Spondias mombin. The lactating ewes were assigned to 2 treatment groups of 6 ewes per group, designated as T1 and T2, respectively. The ewes in T1 were the treated group fed Spondias mombin L. post partum while those in T2 served as a control and were not fed Spondias mombin. Haematological parameters measured include the Packed Cell Volume (PCV) and total white blood cell count while serum biochemical parameters were liver enzyme assay (including Aspartate Transaminase, (AST); alanine amino transferase, (ALT) and Alkaline Phosphatase (ALP) as well as total and conjugated bilirubin. Kidney function tests highlighting urea and creatinine concentrations as well as potassium, sodium, bicarbonate and chlorine ion concentrations were conducted on the control and treated groups. Results showed that S. mombin increased the PDM yield of the lactating ewes in the treatment group over their counterparts in the control group in all the 12 weeks of lactation. These increases were significant (p<0. 05) in the 3rd and 8th weeks. Weeks 3 and 8 PDM values were 61.66 ; 35.44 and 40.31 g; 21.28 g for the treated and control groups, respectively. Spondias mombin did not significantly (p>0.05) influence PCV and WBC values within experimental groups. Also, liver enzymes (ALT, AST and ALP) as well as total and conjugated bilirubin were also not significantly (p>0.05) affected by S. mombin. However, creatinine concentration was significantly higher (p<0.05) in the treated group (0.73 mg dL ¹) than the control group (0.65 mg dL ¹). These results suggest that S. mombin could be useful in improving on the milk production of our WAD ewes; without any adverse effects on their general health and performance.