Effect of partial replacement of concentrate with Prosopis cineraria leaves on nutrient utilization, growth and carcass characteristics of Malpura lambs

A study was aimed to evaluate nutrient utilization, growth, carcass characteristics and meat quality of Malpura lambs fed concentrate mixture containing 10% Prosopis cineraria (Khejri) leaves. Malpura lambs (n=24, ∼3 months old) were distributed into two groups viz., T1 and T2 and fed concentrate mixture with P. cineraria leaves @ 0 and 10% of concentrate, respectively along with basal diet for 90 days. Metabolizable energy (ME) intake was lower (P=0.05) in T2 (1799 Kcal/d) which resulted in lower (P=0.05) average daily gain (131 g) and higher (P=0.03) feed conversion ratio (6.46). Digestibility of dry matter (60.6%), organic matter (63.2%), crude protein (65.4%), ether extract (72.8%), acid digestible fibre (18.1%) and cellulose (19.9%) was decreased and excretion of nitrogen through faeces was increased (P<0.05 resulting in nitrogen per cent of intake. Cooking loss was less (P<0.05), and TBARS (thiobarbituric acid reactive substances) value of meat in T2 (0.46 mg/malonaldehyde/kg meat) was lower (P<0.05) indicating improved oxidative stability. Further, proportion of C18:3 (α-linolenic acid) and total polyunsaturated fatty acid (PUFA) in longissimus thoracis muscle were also higher (P<0.05) in T2 as compared to T1. Hence, it can be concluded that replacement of concentrate mixture with 10% P. cineraria leaves lowered nutrient utilization and increased feed conversion ratio; but it showed positive effects on fatty acid profile and oxidative stability of meat.