Assessing nitrogen (N) mineralization potential of manure is an important precursor for ensuring nutrient use efficiency. N mineralization of agouti and cattle manure was assessed after application to four contrasting soils, incubated for 35 days. Total Kjeldahl nitrogen (TKN) fluctuated over the incubation period and was affected by both soil and manure type. Mineralization was greater in agouti versus cattle manure, with the latter showing immobilization between sampling days 3 and 14. TKN was greatest in Princes Town soil. Ammonium (NH4+) content fluctuated similarly to TKN. Values were significantly higher in the strongly acid soils. Nitrate (NO3-) content decreased with time, stabilising at values just below 50 mg/kg. For the first two sampling times, agouti manure contained significantly higher values compared to cattle manure. Agouti manure can be applied as a soil amendment with consideration of the N supplying potential.