Strain 0083 and two field isolates of H. paragallinarum were previously converted into NAD-independent organisms by the use of crude DNA extractions from naturally occurring NAD-independent H. paragallinarum isolates. Two of these transformed isolates [0083(T) and A745(T)] were used as DNA donors in another transformation experiment in which another field isolate (M85) was used as the DNA recip...

The effect of a continuous disinfection programme, using the non-toxic disinfectant Virukill, in layers, on the spread and impact of infectious coryza, caused by Haemophilus paragallinarum was evaluated. In this experiment, both unvaccinated layers and layers vaccinated against infectious coryza were used. Duplicate smaller groups of vaccinated and unvaccinated chickens were challenged with dif...

Infectious coryza is a well-recognized and commonly encountered upper respiratory tract disease of chickens that is caused by the bacterium Haemophilus paragallinarum. The occurrence of recent outbreaks in North America has emphasized that the disease can be significant in meat chickens as well as layer chickens. In developing countries, coryza is commonly complicated by the presence of a range...