Renal trematode infection in wild birds: histopathological, morphological, and molecular aspects

Gastrointestinal parasites in captive wild birds in Mineiros, Goiás, Brazil

Studying parasites in captive wild birds is vital for their health, well-being, biodiversity preservation, species conservation, and safeguarding of both individual birds and ecosystems. It holds significance for public health by identifying potential zoonotic risks. We aimed to describe the occurrence of gastrointestinal parasites in captive wild birds from a Conservation Institute in Brazilian Cerrado biome. Fresh fecal samples were collected from 17 captive wild birds (Anodorhynchus hyacinthinus, Ara ararauna, Ara chloropterus, Ara macao, Megascops choliba, Pteroglossus castanotis, Ramphastos dicolorus, Ramphastos tucanus and Strix huhula) at a Conservation Institution in Mineiros, state of Goiás. The samples were processed for Willis' simple flotation and Hoffman's spontaneous sedimentation examinations to identify parasitic forms of gastrointestinal endoparasites. Macaw aviary birds (Ar. ararauna, Ar. chloropterus and Ar. macao) showed higher positivity, with all six fecal samples positive for helminths or protozoa. In contrast, captive toucans showed only two positive results (P. castanotis and R. dicolorus). An. hyacinthinus showed Ascarididae, Capillarinae and Trematoda eggs; whereas S. huhula had Ascarididae eggs. Regular parasitological examinations are essential for the timely detection and treatment of gastrointestinal infections in captive birds, thereby enhancing overall bird management.

A Survey of Diseases in Different Species of Wild, Captive, and Illegally Traded Birds in Brazil

Native and exotic avian species can act as reservoirs of pathogens, including bacteria and viruses, with conservation and public health implications. A retrospective study on the diagnosis and frequency of diseases in wild and exotic avian species was conducted. The occurrence of particular diseases was associated with the type of captivity or the bird's origin. The investigation included macroscopic and microscopic descriptions and the molecular determination of the causative agent(s). Additional immunohistochemical (IHC) analysis, PCR, and genetic sequencing were conducted. A total of 243 cases were compiled for the study, mainly consisting of native wild species (39.1%) obtained from illegal trade. Primary infectious diseases, mainly parasitic (18.1%) and viral (17.7%), were the most common, although coinfections were substantial (18.1%) in birds rescued from trafficking. Fractures and neoplasms accounted for 3.7% and 3.3% of the cases, respectively. Parasitic and viral diseases were the most common in both exotic and wild birds. Chlamydia psittaci, a lethal and zoonotic bacterium, was an important cause of death, especially in native Psittaciformes. The recent detection of Psittacid alphaherpesvirus 5 (PsAHV 5) in exotic psittacines and the diagnosis of coinfections in trafficked birds highlight the importance of monitoring avian health to control potential pathogens that may endanger conservation efforts.

Emerging and Re-emerging Diseases of Selected Avian Species

Emerging infections and re-emerging diseases in birds can be caused by numerous factors and need to be recognized and understood. This article introduces and summarizes author-selected emerging and re-emerging diseases of avian species. These diseases hold significance as they relate to scientific research, disease recognition and identification, avian welfare aspects, and ecosystem health. Some are significant in human health and others affect production medicine. These and many others remain important pathogens of worldwide consequence.

Occurrence of Paratanaisia spp. Freitas, 1951 in a domiciled cockatiel (Nymphicus hollandicus, Psittaciformes: Cacatuidae)

Digenetic eucotylids of the Paratanaisia genus are widely reported parasites of the avian renal system. The infection, commonly reported in free-living and zoo-housed birds, is described for the first time in a domiciled bird, a cockatiel kept as pet bird with free access to the yard outdoors. The bird was received at Veterinary Hospital, where clinical and radiographic evaluations suggested a case of heavy-metal poisoning. Although the bird received supportive care and a chelating agent, it died the next day. The necropsy showed friable kidneys and congestion of blood vessels in structures such as the skin, proventriculus, brain, and skullcap. The histopathological evaluation of the kidneys revealed multifocal hemorrhages, commonly found in cases of heavy-metal poisoning. Parasitic structures similar to those of the digenean trematodes Paratanaisia spp. were also observed inside dilated collecting ducts, which presented epithelial cell flattening and vacuolization. There was compression of adjacent tissue and discrete fibrotic areas. In the presence of intermediate hosts in the yard, the synanthropic nature of some wild free-living birds could make them a source of trematodes infection and dissemination for pet birds. Conversely, the infected cockatiel could also have served as a reservoir and carrier of trematodes to wild free-living birds.