Effects of Ascorbic Acid and Levamisole on the Course of Newcastle Disease in Adult Japanese Quails

Abstract

Aims: To investigate the effects of ascorbic acid, levamisole and their combination on the course of Newcastle disease in adult Japanese quails. Study Design: Randomized controlled trial. Methodology: The study was conducted in the University of Maiduguri laboratory in the North East city of Maiduguri, Borno State, Nigeria. One hundred (100) apparently healthy eight (8) weeks old unvaccinated quails were randomly grouped 1-5 of twenty (20) birds each. Four groups (2-5) were challenged with 0.2 ml Viscerotropic Velogenic Newcastle Disease Virus (VVNDV) of chicken origin via oral route. The virus [a viral titer 106.5 per ml of physiologic saline solution (PSS)] was obtained from the National Veterinary Research Institute (NVRI), Vom, Nigeria. Group 1 was maintained as negative control while group 2 was positive control. Groups 3, 4 and 5 were treated with ascorbic acid, levamisole and both respectively. Clinical signs and lesions from dead quails were observed in infected groups. Geometric mean titers of virus antibodies were calculated and then subjected to ANOVA. Results: Depression, anorexia, diarrhea, respiratory distress, drop in egg production and nervousness were observed in all infected groups. Drop in egg production was highest in levamisole-treated birds. Positive control birds had the highest morbidity of 45% followed by ascorbic acid-treated (35%), levamisole-treated (25%) and ascorbic acid-levamisole-treated (25%) birds. Ascorbic acid-levamisole-treated birds recorded 5% mortality whilst the other infected bird groups had 10% mortality each. The GMT of Newcastle Disease Virus (NDV) antibodies revealed that positive-control birds could not attain the protective antibody titer of 5.2, whereas ascorbic acid, levamisole and ascorbic acid-levamisole treated birds attained protective titers 6.1, 7.5 and 11.3 respectively. Conclusion: Treatment with ascorbic acid and levamisole mitigated morbidity and mortality in velogenic NDV infection, while the combination of ascorbic acid and levamisole had a better outcome (synergistic effect).