Pattern of waning of maternal antibodies against newcastle disease of chicks from selected hatcheries in Kumasi, Ghana.
This study was conducted to measure and compare the rate at which maternal antibodies against Newcastle Disease (ND) wane in chicks from some selected hatcheries in Kumasi, Ghana. Sera from 150 unvaccinated cockerels collected from three hatcheries (A, B, C) were screened using standard methods of heamagglutination inhibition technique. Two separate vaccination schedules against ND were employed in advising poultry farmers at the Regional Veterinary Laboratory were compared for their suitability. Descriptive statistics was employed. All the chicks from the three hatcheries had maternal antibodies against ND at day-1 and that the maternal antibodies lasted till day-21. Hatchery A had the highest maternal antibody titre of 9.97 GMT at day-1, followed by B with 7.84 GMT and C having the lowest GMT of 6.70. Based on the vaccination schedule, schedule (I) which puts the first Newcastle vaccination at 8 days old (week 1) would not be favourable for any of the chicks that were obtained from the three hatcheries due to the presence of protective maternal antibody levels (4.0 GMT) in sera obtained from chicks during the first week of age. Schedule (II) which puts the first ND vaccination at day-15 favored hatcheries A and C. This is because the MAb titres of chicks from hatcheries A and C decayed below the protective titres after day- 14. This study represents the first report on waning pattern of Newcastle disease specific MAb in chicks in Ghana and it also showed that vaccination schedule should take cognizance of MAb evaluation for the control incessant ND outbreaks.
Keywords: Decay, Maternal antibodies (MAb), Newcastle Disease (ND), Vaccination schedule, Ghana