A mobile killing- and mincing unit represents a possible alternative in mass destruction of AIV infected poultry

In Denmark the veterinary authorities have approved a mobile mechanical unit for humane culling and processing of end-of lay hens. The elimination of transportation of live table egg layers is from a welfare point of view valuable, and in this respect, this multifunctional unit performs the initial steps in the disposal process. At first, the hens are transported into a chamber where they are killed by CO2. The dead hens are subsequently transported on a conveyor belt to the disintegrating mincing device, and the produced pulp is accumulated in a container under constant mechanical stirring. In order to prevent bacterial growth and putrefaction, the pulp is acidified to pH below 2.0. Finally, the pulp is transferred via closed pipes to a container on a lorry before transportation to its final destination as mink feed. Importantly, all steps in this process are strictly supervised and adjusted according to standards. As this mobile unit minimises the risk of spreading pathogens, it represents an attractive approach in case of AIV outbreak in poultry flocks. This requires, however, that the acidification step is sufficient to inactivate infectious AIV. Therefore, low pathogenic AIV subtype H5N2 was added in the laboratory to freshly produced pulp, and the survival of infectious virus as well as presence of genome segments were monitored over a 24-hour period. Interestingly, H5N2 AIV was instantly inactivated in the acidified pulp, whereas AIV survival was documented for at least 24 hours in the non-acidified control.