Nutrient digestibility, performance, carcass characteristics and blood parameters of fattening Zandi lambs fed by different levels of black seed (Nigella sativa) meal

To study the effects of replacing canola meal with black seed meal on performance, blood parameters and carcass characteristics, eighteen male lambs (with initial BW, 29.5 ±1.5 kg and 110 ± 7 days of age) were used in a completely randomized design with 3 different treatments over 90 days. Experimental treatments were: 1) control; diet containing 9% canola meal, 2) diet containing 4.5 % canola meal plus 4.5 % black seed meal and 3) diet containing 9 % black seed meal. The amount of dry matter, ash, crude protein, fat, NDF, ADF, and ADIN of black seed meal was 92.60 ±0.58, 7.24±0.27, 35.8±1.0, 12.31±0.51, 24.56±1.24, 13.0±0.79 and 2.15±0.17, respectively. There were no significant differences between treatments for digestibility of organic matter, NDF, fat and protein. Daily feed intake, feed conversion ratio, daily weight gain, final body weight, carcass efficiency, weight of liver, heart, kidney and testis were not differed between experimental groups. However, lambs fed with black seed meal had lower level of subcutaneous fat, tail-fat and total body fat deposition compared to control group (P<0.05). Feeding 9% black seed meal increased blood total protein and albumin concentration compared to the other experimental groups (P<0.05). The results of this study showed that it could be feasible to use black seed meal up to 9% in finishing lamb diet.