Morphology and morphometry of three Plasmodium juxtanucleare (Apicomplexa: Plasmodiidae) isolates

Interactions ofPlasmodium juxtanucleareand chicken anaemia virus: establishing a model

The pathogensPlasmodium juxtanucleareand chicken anaemia virus (CAV) are easily transmitted and potentially harmful to chickens. In this study, we established an experimental model to investigate the effects of avian malaria caused byP. juxtanuclearein white leghorn specific-pathogen-free (SPF) chicks previously immunosuppressed with CAV. Parasitaemia, haematological variables and clinical and pathological parameters were determined in four different experimental groups: chicks coinfected by CAV andP. juxtanuclearestrain (Coinfected group), chicks exclusively infected by CAV (CAV group) orP. juxtanucleare(Malaria group) and uninfected chicks (Control group). Our data demonstrated thatP. juxtanucleareparasitaemia was significantly higher in the Coinfected group. Furthermore, haematological parameters, including the RBC, haematocrit and haemoglobin concentration were significantly reduced in coinfected chicks. In agreement with the changes observed in haematological features, the mortality among coinfected chicks was higher compared with animals with single infections. Clinical analysis indicated moderate changes related to different organs size (bursa of Fabricius, heart and liver) in coinfected birds. The experimental coinfection of SPF chickens withP. juxtanucleareand CAV may represent a research tool for the study of avian malaria after CAV immunosuppression, enabling measurement of the impacts caused by different pathogens during malarial infection.