title: Revaccination of chicks for Marek's disease at twenty-one days old.
abstract: Chicks vaccinated for Marek's disease (MD) at both 1 and 21 days old did not suffer significantly different losses from MD than did chicks vaccinated at 1 day old only. This was true even with vaccinations of 1-day-old chicks with increasingly higher titers. The failure of revaccination to reduce losses from MD could be attributed to the age at which natural exposure occurred.
mesh_terms: D000367:Age Factors; D000818:Animals; D002645:Chickens; D005260:Female; D007115:Immunization Schedule; D008380:Marek Disease / Q000517:prevention & control*; D014611:Vaccination / Q000662:veterinary*