Evaluation of poultry litter as substitute of urea in urea molasses block on growth and carcass characteristics of finished lamb

Abstract

This study examined the replacement effect of urea molasses block with dried caged layers excreta (PE) on feed intake, digestibility, growth performance, carcass characteristics and cost of production of growing lambs. Treatments (T) varied only with type of feed block supplemented: where dried PE replaced urea of a block (weight by weight) at 0%, 25%, 50%, 75% and 100% in treatments 1, 2, 3, 4 and 5, respectively. Lambs were randomly allotted to treatments in a Complete Randomized Design, individually penned and fed daily on tef straw ad libitum and 300 g of noug cake (Guizotia abyssnica) in addition to block supplementation. Dry matter (DM) intakes of straw, noug cake, feed blocks and total feed were improved significantly (p<0.001) with inclusion of block PE up to 50%. Straw DM intake was increased (p<0.01) from 419 g in T1, to 472 g in T2, but not depressed at higher rates of PE inclusion. Block DM intake increased from 148g (T1) to 179 g (T5), and the corresponding total intakes were 832 and 890 g, respectively. Digestibility coefficients were not considerably affected (p>0.05) by treatments ranging from 0.60 to 0.64; 0.32 to 0.43 and 0.62 to 0.67 for DM, ash, organic matter, respectively. The average daily weight gain was increased (p<0.001) with block PE inclusion, in which both the highest weight gain (54g) and feed conversion efficiency (18.1g DMI/g gain) were attained by lambsin T2.. The highest cold carcass weight (11.3 kg) and dressing percentage (45.4) were observed at the highest inclusion rate of PE (T5). Profit per lamb was highest in T2 (79.9 ETB) and lowest in T5 (67.9 ETB). Cost of production of a block was reduced from 2.05 to 1.43 ETB as PE inclusion increased from 0 to 100 %. Moreover, no health problem was detected in lambs due to feeding PE containing block. This study indicates that use of PE as a substituent for urea in urea molasses block production improves growth performance and feed utilization, and reduces cost of lamb feeding.