Studies on some fern species have revealed their suitability for use in fortifying livestock and fish feeds to enhance food production. The intake of Nephrolepis biserrata (Swartz) Schott by ruminants in the tropics has been reported. Thus, its nutrient compositions were determined in this study. Proximate analysis showed 6.13 % protein, 0.87 % crude fiber, 0.33 % fat, 1.88 % ash, 80 % moisture, 10.87 % carbohydrate, 20 g/100 g total solid and 4.79 mg/100 g ascorbic acid (vitamin C). The leaflet is a rich source of mineral elements (mg/100 g dry matter): chromium 6.30±0.01, iron 1182.00±0.49, manganese 100.80±0.02, copper 158.75±0.38, cobalt 0.45±0.02, cadmium 0.02±0.03, lead 68.10±0.17, magnesium 338.70±0.01, calcium 223.20±0.06, mercury 27.59±0.11, nickel 9.00±0.03, potassium 500.00±0.04 and sodium 250.00±0.05. Zinc, selenium and arsenium were not detected. Analysis of the toxicants also showed oxalate and hydrogen cyanide to be 0.575 mg/100 g and 2.16 mg/100 g respectively. The results are discussed in terms of the nutritive value as well as the public health implication of having N. biserrata as part of the ruminant diet.
Keywords: elemental analysis, fossils, gametophytes, herbivores, Nephrolepis, proximate compo-sition, pteridophyte, toxicants.