Dietary Inclusion of Black Cumin (Nigella sativa L.) Seed Meal in Broiler Chickens: Effects on Growth Performance, Cecal Microbiota, and Cost Efficiency

The current study evaluated the effects of black cumin seed meal (BCSM) on growth performance, cecal microbiota, production efficiency, and cost efficiency in broiler chickens. A total of 144 one-day-old unsexed Cobb 500 broiler chicks were randomly assigned to four treatment groups, each with three replicates of 12 chicks using a completely randomized design. Broilers were fed iso-caloric and iso-nitrogenous diets containing 0% (BCSM0, control), 1.5% (BCSM1.5), 3% (BCSM3), and 4.5% (BCSM4.5) BCSM over a 45-day feeding trial. The results showed no significant differences ( P > 0.05) in feed intake, weight gain, or carcass characteristics among different treatments. However, feed conversion ratio (FCR) was significantly improved ( P = 0.043 and P = 0.027) in BCSM4.5 during the finisher and entire periods, respectively compared with the control, which may be associated with slightly lower feed intake and the reported bioactive compounds in BCSM that may enhance digestion and feed utilization. Regarding the cecal microbiota, the inclusion of BCSM significantly reduced total coliform ( P = 0.009) and E. coli ( P = 0.002) counts while significantly increased ( P = 0.007) beneficial Lactobacillus populations, although the total bacterial load was not affected. Production efficiency factor and European broiler index were significantly better ( P = 0.018 and P = 0.019, respectively) at the highest level of inclusion (4.5%) compared to the control. Partial budget analysis revealed that net income and the marginal rate of return were better for BCSM treatments groups. In conclusion, this study demonstrates that BCSM can be utilized as an alternative feed ingredient for broiler chickens. Inclusion of BCSM up to 4.5% beneficially modulated cecal microbiota, reduced mortality, and improved FCR, production efficiency, and cost efficiency, depending on the inclusion level, without adversely affecting growth performance.