Effects of Natural Guard Liquid (an Essential Oil-Based Product) on Growth Performance, Hematological Profile, and Antibody Response to Newcastle Disease Virus in Broiler Chickens

Abstract

Natural guard liquid (NGL) is an immunomodulator consisting of an essential oil blend (lavender oil, eucalyptus oil, and pine oil) that can improve the immunity (IgG) of animals. The objective of this research was to assess the effectiveness of a mixture of NGL comprising of essential oil (eucalyptus, lavender, and pine oil) on growth performance, hematological profile, and antibody titer response to the Newcastle disease virus (NDV) in Lohman strain broiler chickens. A total of 400-day-old unsexed broiler chickens with an average weight of 42.48 ± 2.08 g were randomly distributed into four groups, each comprising two replications with 50 chicks. The control group, T0, received no essential oil, while other treatment groups, T1, T2, and T3, were administered NGL at 80, 100, and 200 ppm, respectively. The mixture was administered in drinking water for 30 days. The animals had received vaccinations at the Hatchery, including active NDV, inactive NDV, and Gumboro. Regular recordings were made for feed consumption, water intake, mortality, and body weight. Blood samples for routine hematological examination (hemoglobin, erythrocytes, packed cell volume, erythrocyte index, leucocytes, and differential leucocytes) and immune parameter (NDV antibody titer) assessment were collected at the onset as well as after 15 and 30 days of treatment. The hemoglobin levels, erythrocytes, total leukocytes, lymphocytes, and Heterophil-lymphocyte index showed significant differences in groups T1 and T2 compared to T0. While the NDV antibody titer showed a significant difference at T2 compared to T0, it was not significantly different at T1 and T3. The best results and performance was indicated in T2 (100 ppm), characterized by body weight (1,839 g), and feed conversion ratio (1.573). The hematological profile in the T2 group included hemoglobin (11.78 g/dL), total erythrocytes (2.82 ×106 u/L), total leukocytes (52.67 ×103 u/L]), and the NDV antibody titer (48 ± 10.20) in the fifth week. In conclusion, the optimum dose of NGL is 100 ppm, which significantly influences growth performance, hematological profile, and antibody titer against NDV. Keywords: Antibody titer, Broiler chicken, Growth performance, Hematological profile, Natural Guard Liquid