University of Guilan Animal Production Research 2252-0872 10 4 2022 02 20 Effect of black cumin and black seed on growth, weight gain, and blood parameters of fattening lambs under rangeland grazing condition Effect of black cumin and black seed on growth, weight gain, and blood parameters of fattening lambs under rangeland grazing condition 49 59 5458 10.22124/ar.2022.16793.1536 FA A. Yavari Former MSc Student, Department of Animal Science, Faculty of Agricultural Science and Engineering, Razi University, Kermanshah, Iran M. M. Moeini Associate Professor, Department of Animal Science, Faculty of Agricultural Science and Engineering, Razi University, Kermanshah, Iran F. Hozhabri Associate Professor, Department of Animal Science, Faculty of Agricultural Science and Engineering, Razi University, Kermanshah, Iran Journal Article 2020 07 19 In this study, the effect of black cumin and the black seed was evaluated on the growth, blood metabolites, thyroid hormones, and liver enzymes activity of lambs under pasture grazing conditions.  Twenty-four Sanjabi male lambs in their four to five months of age (live weight of 30 ±0.9 kg) were used in four treatments and six replicates in a completely randomized design for 70 days. Treatments included group 1: Control (rangeland forage), group 2: Rangeland forage plus 0.3 g of black seed per kg body weight (BW), group 3: Rangeland forage plus 0.3 g of black cumin per kg BW, and group 4: Rangeland grass plus 0.15 g of black seed + 0.15 g of black cumin per kg BW. The lambs were weighed every two weeks. Blood samples were collected from the jugular vein on days one, 35, and 70 of the experiment. Adding black seed and cumin had no significant effect on growth performance, but significantly increased total blood protein in treated groups (<em>P</em><0.05). The blood urea level of lambs in treated lambs was lower than in the control group. Thyroxine concentration in lambs fed on black seed was higher than that of other groups (<em>P</em><0.05). The activity of aspartate aminotransferase and alanine aminotransferase was lower in the herbal supplemented groups than in the control group (<em>P</em><0.05). Overall, the results of this experiment showed that incorporation of these amounts of black seed and black cumin to the diet as herbal supplements improved some blood parameters, but had no significant effect on growth performance. In this study, the effect of black cumin and the black seed was evaluated on the growth, blood metabolites, thyroid hormones, and liver enzymes activity of lambs under pasture grazing conditions.  Twenty-four Sanjabi male lambs in their four to five months of age (live weight of 30 ±0.9 kg) were used in four treatments and six replicates in a completely randomized design for 70 days. Treatments included group 1: Control (rangeland forage), group 2: Rangeland forage plus 0.3 g of black seed per kg body weight (BW), group 3: Rangeland forage plus 0.3 g of black cumin per kg BW, and group 4: Rangeland grass plus 0.15 g of black seed + 0.15 g of black cumin per kg BW. The lambs were weighed every two weeks. Blood samples were collected from the jugular vein on days one, 35, and 70 of the experiment. Adding black seed and cumin had no significant effect on growth performance, but significantly increased total blood protein in treated groups (<em>P</em><0.05). The blood urea level of lambs in treated lambs was lower than in the control group. Thyroxine concentration in lambs fed on black seed was higher than that of other groups (<em>P</em><0.05). The activity of aspartate aminotransferase and alanine aminotransferase was lower in the herbal supplemented groups than in the control group (<em>P</em><0.05). Overall, the results of this experiment showed that incorporation of these amounts of black seed and black cumin to the diet as herbal supplements improved some blood parameters, but had no significant effect on growth performance. https://ar.guilan.ac.ir/article_5458_2e390b0662b920a8e056f208332bbd21.pdf