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The apicomplexan parasite Sarcocystis calchasi (S. calchasi) triggers pigeon protozoal encephalitis, a neurologic disease in columbids. Accipiter hawks have been identified as the final host, and Columbidae and Psittaciformes as intermediate hosts. In this study, 368 free-ranging Accipiter hawks and 647 free-ranging common woodpigeons were sampled in a country-wide study in order to identify the prevalence of S. calchasi in these populations. A semi-nested PCR specific for S. calchasi tested positive in 7.3% (4.9–10.5) of submitted samples from Accipiter hawks. Juvenile Accipiter hawks (13.7%; 7.7–22.0) had a significantly higher infection rate with S. calchasi than adult Accipiter hawks (5.8%; 2.7–9.3). The prevalence of S. calchasi in common woodpigeons was 3.3% (5.4–9.7). Positive pigeons were identified in 14/16 federal states, and a region-dependency was detected, with higher rates of infection in the eastern parts of Germany. The results of this study suggest that the common woodpigeon is a natural reservoir for S. calchasi. In a study of one region for four consecutive years, an increase in prevalence was not detected. Findings indicate that the parasite is not newly introduced to Germany, but rather long established. The prevalence suggests that there is a substantial risk of S. calchasi infections in other free-ranging as well as captive host species.

In this case report, a 4.5-year-old Pacific parrotlet (Forpus coelestis) with a generalized hematopoietic neoplasia is described. The patient was presented with severe unilateral exophthalmos of the right eye and a poor general health condition. Neither in the general nor the ophthalmologic, nor the subsequent microbiological and mycological examination signs of infection were detected, and molecular tests for Chlamydia psittaci were negative. As the bird’s condition decreased despite intensive care treatment, euthanasia was performed. Postmortem examination revealed a large, space-occupying, bloody mass in the right orbita, displacing the globe. The calvaria seemed to be involved as well as the Paries dorsalis and Paries caudalis of the orbita. Histopathology identified tumor cells in the liver, the spleen, the kidneys, the right eye, and the surrounding orbita, indicating a generalized lymphoma as underlying cause. Immunohistochemical analysis confirmed the swelling to be of B-cell origin. This case report demonstrates that neoplasms should be included in the list of differentials for exophthalmos in psittacines. Moreover, diagnostic options to work off an exophthalmos are described with a special focus on hematopoietic neoplasms in psittacines.

Between June and November 2015, 25 woodpeckers (Picidae) with neurologic signs or unknown cause of death were admitted to a veterinary clinic. Alive birds were clinically examined. Birds that were found dead or died despite intensive care treatment were forwarded to a pathologic examination. Necropsy and subsequent tests included screening for several infectious agents and toxins. Three birds tested positive for Sarcocystis calchasi. Toxoplasma gondii was detected in one bird demonstrating intracerebral cysts. Mycoplasma gypis was detected in one woodpecker in the absence of respiratory signs. Several microbial pathogens (eg, Aspergillus fumigatus, Clostridium perfringens, and Escherichia coli) were isolated from single individuals. However, there was no consistent finding in all birds that could explain nervous signs and mortality of the woodpeckers examined. To the authors‘ knowledge, M. gypis and S. calchasi were detected in a woodpecker for the first time in this study.