Effects of Mineral Soil and Dicalcium Phosphate Mix Supplementation on Performance of Sheep Fed on a Diet of Urea-Treated Maize Stover.

BACKGROUND: Ruminants mostly rely on crop residues for extended periods, often lacking essential minerals. Enhancing these low-quality feeds with supplements is a key intervention to improve feed intake, digestibility and animal performance. Thus, this study evaluated the effect of mineral soil (MS) and dicalcium phosphate (DCP) mix supplementation on feed intake, weight change, digestibility and carcass characteristics of Hararghe highland sheep fed on urea-treated maize stover (UTMS). METHODS: The experiment was undertaken in a randomized complete block design in 5 groups using 25 male yearling lambs (initial body weight of 16.65 ± 0.18 kg). The treatments were UTMS ad libitum + 300 g dry matter (DM) concentrate mixture (75% wheat bran and 25% noug seed cake) (T1, control), T1 + 2.5% MS (T2), T1 + 2.5% MS and DCP mix at 75:25 (T3), T1 + 2.5% MS and DCP mix at 50:50 (T4) and T1 + 2.5% MS and DCP mix at 25:75 (T5). The trial took 90 days of feeding and 7 days of digestibility trials. RESULTS: The intake of UTMS on a DM basis was higher (p < 0.05) for the mineral-supplemented group (434.56-486.83 g/day) than for the non-supplemented group (366.93 g/day), except for T3 (379.16 g/day). Total crude protein (CP) and DM feed intake were higher (p < 0.05) for the mineral-supplemented (734.56-786.83 g/day) than for the non-supplemented (666.93 g/day), except for T3 (679.16 g/day). Total intakes of DM and CP were not affected (p < 0.05) by adding DCP compared to MS alone. Supplementation with MS and its mixture with DCP improved (p < 0.05) the digestibility of DM, CP, organic matter (OM), neutral detergent fibre (NDF) and acid detergent fibre (ADF), except at T3. Supplementation with MS and its mixture with DCP improved (p < 0.05) the average daily gain, slaughter weight and empty body weight. At the same time, the effect was non-significant (p > 0.5) on hot-carcass weight, dressing percentage and rib eye muscle area. CONCLUSIONS: The result of the study showed that MS supplementation is crucial for improving productivity by enhancing intake and digestibility, whereas replacing different proportions of MS with DCP did not improve the performance of sheep.