Influence of Maternal Antibody on Infection with Virulent or Attenuated Marek's Disease Herpesvirus

Abstract

SUMMARY One-day-old chicks with maternal antibody (flock A) were significantly more resistant ( P < 0.01) to Marek's disease ( md ) than were chicks of the same genetic stock but without antibody (flock B). Genetically susceptible Cornell S-strain chicks, used in one experiment for comparison, and flock B chicks had similar susceptibility when inoculated intra-abdominally at 1 day of age. Results of viral isolations in cell culture indicated that kidney of chicks from flock A had significantly fewer infected cells ( P < 0.01) than did that from flock B or S-strain chicks. Maternal antibody also interfered with immunity induced by attenuated md herpesvirus ( mdhv ). In immunization studies, flock B chicks vaccinated with attenuated virus at 1 day of age were significantly protected ( P < 0.01) against subsequent challenge inoculation with virulent virus, whereas flock A chicks were not protected.