Published by the Agricultural Research Council, Onderstepoort Veterinary Institute
Abstract
Atypical Haemophilus paragallinarum have been isolated from both laying hens and broilers suffering
from typical symptoms of infectious coryza in South Africa. Re-inoculation of these bacteria into SPF
chickens resulted in similar pathology. The bacteria could be successfully re-isolated from the experimentally
infected chickens.
Four of the isolates from layers and 3 of those from broilers were found to be closely related to H.
paragallinarum serotype A (0083 strain) when tested by the use of a panel of locally developed
monoclonal antibodies in the enzyme linked immunosorbent assay (ELISA) . A total of 15 isolates from
layers and 19 from broilers were found to be more typical of previously collected South African field
isolates of H. paragallinarum. A 3rd group, consisting of 5 isolates from layers and 15 from broilers,
showed no reaction with the panel of monoclonal antibodies.
All the isolates were regarded as atypical because they no longer required V factor (NAD) for growth,
whereas strain 0083 and previously collected field isolates M 85 and SB 86 did require it.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.South African Egg Board. National Cancer Association.mn201