European Scientific Journal September 2014 edition vol.10, No.27 ISSN: 1857 – 7881 (Print) e - ISSN 1857- 7431 132 EVALUATION OF THE EFFICACY OF NEWCASTLE DISEASE (LASOTA) LIVE VACCINES SOLD IN JOS, PLATEAU STATE, NIGERIA Akele Y. Richard Department of Medical Laboratory Science, College of Medicine and Health Sciences, AfeBabalola University. Ado - Ekiti, Nigeria Tatfeng Y. Mirabeau Department of Medical Laboratory Science, College of Health Sciences, Niger Delta University, Wilberforce Islan, Bayelsa State, Nigeria Ojiezeh I. Tony Department of Medical Laboratory Science, College of Medicine and Health Sciences, AfeBabalola University. Ado - Ekiti, Nigeria Chollom C. Solomon Virology Research Department, National Veterinary Research Institute, Vom, Plateau State, Nigeria Enitan S. Samsom Department of Physiology, College of Health Science, Igbinedion University Okada, Benin City, Edo State, Nigeria Olayanju O. Ayodeji Department of Medical Laboratory Science, College of Medicine and Health Sciences, AfeBabalola University. Ado - Ekiti, Nigeria Abstract Introduction: Newcastle Disease is a highly contagious and commonly fatal viral poultry disease. The study was carried out to determine the efficacy of Newcastle Disease (NDV) vaccines sold at open market in Jos. Materials and methods: Five commonly used brands of ND LaSota live vaccines were used for the study. Haemagglutination test (HA) and Egg Infective Dose (EID 50 ) was carried out on the vaccines.Sixty (60) day-old unvaccinated white leghorn broilers were distributed into 6 groups n=10 and allowed to acclimatize for 6 days. Groups 1-5 were vaccinated intraoculally with vaccines coded A - E respectively, while group 6 was not vaccinated (control group). They were bled on days 7, 14, 21 and 28 post vaccinations (PV) for antibody titration using standard methods. They were challenged