Oregano (Origanum vulgare Linn.) Powder as Phytobiotic Feed Additives Improves the Growth Performance, Lymphoid Organs, and Economic Traits in Broiler Chickens

Abstract

Antibiotics have long been recognized as growth promoters and disease controllers in poultry production. However, due to rising public health concerns over antibiotic-resistant bacteria, the use of antibiotics in livestock and poultry feed has been banned in the European Union since 2006. Thus, this study was conducted to determine the effects of oregano powder (OP) as phytobiotic feed additives on the growth performance and cell-mediated immunity of broiler chickens. A total of sixty-day-old Cobb-broiler chickens were used in the study and arranged in a Completely Randomized Design experimental set-up with four dietary treatments. Each treatment was replicated three times, having five birds in every replication. The experimental rations containing graded levels of OP (0%, 1%, 3%, and 5%) were formulated and fed ad libitum in 42 days feeding trial. The results indicated that broiler chickens fed with OP showed a significant increase (p<0.05) in the final weight, body weight gain, voluntary feed intake, and feed conversion ratio. The cell-mediated immunity showed no significant difference (p>0.05) among treatment means. However, the results revealed that the immune organ indicators of broiler chickens fed with OP were higher than those birds without OP in the diet. On the other hand, the total expenses of broiler chickens fed with 5% oregano powder were reduced by 5.81% of the total inputs, and the income generated increases as high as 30.86% of the return above feed and chick cost. In conclusion, 5% oregano powder can be incorporated without adverse effects on the production performance and cell-mediated immunity.