Visser, LeonVermeulen, Nico2021-11-022021-11-0220211988*http://hdl.handle.net/2263/82512Thesis (PhD)--University of Pretoria, 1988.Monoclonal antibodies represent the ultimate in specificity of serological analysis and diagnosis. Combined with the sensitivity and versatility of enzyme linked immunosorbent assay (ELISA), it provides a powerful tool to distinguish between closely related analytes where this is not easily accomplished by conventional means. The purpose of this study was to extend the application of ELISA and monoclonal antibodies, or account for imperfections in a selected number of situations of interest to the field of agriculture.© 2021 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.UCTDantibodies against dihydrogrieseninatrazine and HaemophilusThesis