Evaluation of Nutritive Value of Vegetable Wastes Grown in North Central Nigeria using in Vitro Gas Production Technique in Ruminant Animals

The potential value of nine different types of vegetables wastes that had expired the date of display in the open market shelves, were evaluated as a ruminant feed source through in vitro gas production technique and the organic matter digestibility (OMD), short chain fatty acid (SCFA) and metabolisable energy (ME) was estimated. The results obtained showed wide variations in crude protein (2.61-18.44%), crude fiber (14.84-32.04%), carbohydrate (46.07-73.52%), neutral detergent fiber (43.59-66.37%) and acid detergent lignin (4.63-10.34%). Okro recorded the highest values (%) for NDF (66.37), ADF (43.68), cellulose (34.54). hemicellulose (22.69), and CF (32.04) while cabbage had the richest content of CP (18.44). The mineral contents varied significantly (p < 0.05) among the investigated vegetable wastes. Cabbage contained high contents of Na (7.23 g/kg), P (3.10 g/kg) and Cu (18.43 ppm) whereas carrot (61.20ppm) and water-mellon had high contents of Fe compared with other vegetables wastes. The total gas volume at 24h, 48h and 72h were highest for potato, followed by okro and the lowest value recorded for onion. The estimated OMD (%), SCFA (µmol) and ME (MJ/Kg DM) ranged from 54.10 to 76.12, 0.490 to 1.40 and 6.31 to 10.70 respectively, being highest in potato (76.12%, 1.40µmol and 10.70 MJ/KgDM) followed by okra (64.52%, 1.087µmol 9.07MJ/Kg DM) and water melon (60.27%, 0.82µml and 7.97MJ/Kg DM). From the results obtained in this study, a number of these vegetables could be utilized as supplementary sources of protein, energy and mineral for livestock. However, low dry matter content of these feeds may interfere in the variability of their transport and utilization in north central Nigeria.