The Influence of Organic Manures on Proximate Composition, Minerals, Anti-nutrients and Vitamins of Selected Legume Forage

Abstract

This study investigated the influence of three organic manure on the nutritional composition of three leguminous forages - Soybeans, Cowpeas, and Groundnuts, cultivated in the coastal Rainforest of Akwa Ibom State, Nigeria. The four different organic manure used were poultry droppings, goat droppings, pig dung and a control (no manure application). Each organic manure represented a treatment group. Each group was replicated three times making a total of 12 experimental units. The data collected were subjected to analysis of variance using the Statistical Package for Social Science (SPSS). Proximate analysis revealed significant (p<0.05) differences in moisture, fat, ash, protein, fiber, carbohydrates, and energy content. Manure type significantly (p<0.05) affected protein, carbohydrate, and moisture content. Poultry Manure had superior performance in Cowpea Forage, while Control excelled in Soybean Forage. The anti-nutrient analysis revealed significant (p<0.05) differences in tannin, oxalate, saponin, and phytate content, impacting nutritional quality. Tannin content varied significantly (Groundnut: 65.78 mg/100g, Soybean: 109.78 mg/100g, Cowpea: 37.62 mg/100g), as did oxalate (Groundnut: 393.18 mg/100g, Soybean: 185.20 mg/100g, Cowpea: 357.13 mg/100g), saponin (Groundnut: 5.71 mg/100g, Soybean: 6.63 mg/100g, Cowpea: 6.63 mg/100g), and phytate (Groundnut: 160.89 mg/100g, Soybean: 30.63 mg/100g, Cowpea: 21.22 mg/100g). Vitamin analysis revealed variations in vitamin C (Groundnut: 57.94 mg/100g, Soybean: 58.31 mg/100g, Cowpea: 63.17 mg/100g) and β-carotene (Groundnut: 9.73 mg/100g, Soybean: 9.46 mg/100g, Cowpea: 7.51 mg/100g), indicating nutritional attributes of the studied leguminous forages. Based on the results, the treatment involving poultry dropping, goat dropping, pig dung and control all demonstrated good performance in terms of contributing to the nutritional composition of cowpea, groundnut and soybean. Thus, the use of poultry dropping and pig dung as organic manure for farmers in the region could be recommended.