Poultry Diseases: The Christensen Group
The main purpose of the group is to study various aspects of different poultry diseases. The focus is on bacterial infections but viral and non-infectious diseases are also of interest. Epidemiology and pathogenesis of diseases are key areas using agent characterization, pathology and in vivo infection models as the most important tools.
Globally, poultry production is increasing due to many positive aspects concerning this source of animal protein. However, diseases and zoonotic infections affecting food safety continue to be of concern.
In our group we focus on the understanding of production diseases including bacterial infections caused by Gram positive cocci and E.coli using microbiological methods and in vivo infection models.
These infections taken together accounts for up to half of the non-outbreak related mortality observed in commercial settings. Consequently, understanding and controlling these infections will have a major positive impact on the production.
In addition, the experienced increase in free range production over the years requires focus on routes of transmission of more exotic infections.
Recent years, non infectious conditions such as keel bone fractures affecting animal welfare and productivity also has become a major research area of the Christensen group
Significant impact of strain and host factors on the clinical and pathological outcome
By the use of a infection model developed by the group we were able to demonstrate E.coli strain variation concerning disease causing capability. In addition, differences in susceptibility to infection between meat type hens and layers could be observed.
Rikke Heidemann Olsen, Ida Cecilie Naundrup Thøfner, Susanne Elisabeth Pors, Jens Peter Christensen (2016). Experimental induced avian E. coli salpingitis: Significant impact of strain and host factors on the clinical and pathological outcome. Veterinary Microbiology. 188, s. 59-66 8 s
Correlation between footpad lesions and systemic bacterial infections in broiler breeders.
The observation that older birds with poor foot pad health often develop systemic Gram positive infections resulting in mortality and decreased welfare was clearly demonstrated in the following study.
Ida Cecilie Naundrup Thøfner, Louise Ladefoged Poulsen, Magne Bisgaard, Henrik Christensen, Rikke Heidemann Olsen and Jens Peter Christensen(2019). Correlation between footpad lesions and systemic bacterial infections in broiler breeders. Veterinary Research 2019 50:38. https://doi.org/10.1186/s13567-019-0657-8
Pathological characterization of keel bone fractures in laying hens does not support external trauma as the underlying cause
Submitted to PlosOne: In a cross disciplinary study, it was demonstrated that the commonly accepted hypothesis that external trauma causes keel bone fractures in layers cannot be the the only explanation for this condition.
Ida Thøfner, Hans Petter Hougen, Chiara Villa Niels Lynnerup, and Jens Peter Christensen (2019). Pathological characterization of keel bone fractures in laying hens does not support external trauma as the underlying cause. Submitted to PlosOne
Poultry Levy Fund
Danish Veterinary and Food Administration