Infectious coryza is caused by Haemophilus paragallinarum organism. The V factor (nicotinamide adenine dinucleotide, NAD) requirement of this organism is critical for its substantial growth in artificial media. Baker's yeast is one of the known sources of V factor. It is also a cheap source of V factor compared to the commercially available reduced NAD. A bacterin against H. paragallinarum serotype A was produced using extracted baker's yeast supplemented tryptic soy broth. The prepared vaccine gave a 53.33% protection from the progressive development of exudates in the upper respiratory tract, and 60% protection from bacterial colonization of the upper respiratory mucosae. Comparative histopathological examination showed severe lesion in unvaccinated but not in vaccinated chickens.