Cerebral baylisascariosis in a rainbow lorikeet (Trichoglossus moluccanus) in a German Zoo.

BACKGROUND: The raccoon roundworm, Baylisascaris procyonis, can cause a meningoencephalitis as neural larva migrans which is known in avian species, including rainbow lorikeets in North America, but has not been described in Old World parrots in Germany yet. CASE PRESENTATION: A 2-month-old, male rainbow lorikeet from a zoo in Germany was submitted for necropsy. Prior to death the animal had progressive neurological signs like apathy and torticollis. In the cerebrum a focally extensive severe granulomatous to necrotizing encephalitis with an intralesional larval nematode was diagnosed. Based on the clinical and pathological findings, the larval morphology and the epidemiological background, the larva was identified as Baylisascaris procyonis. CONCLUSIONS: Cerebral baylisascariosis should be considered as a differential diagnosis in zoo and pet birds with neurological signs having contact to racoons or rather racoon faeces in Germany due to the high prevalence of Baylisascaris procyonis in the German raccoon population.

Clostridium perfringens-Associated Necrotic Enteritis-Like Disease in Coconut Lorikeets (Trichoglossus haematodus).

Several outbreaks of necrotic enteritis-like disease in lorikeets, from which Clostridium perfringens was consistently isolated, are described. All lorikeets had acute, segmental, or multifocal fibrinonecrotizing inflammatory lesions in the small and/or the large intestine, with intralesional gram-positive rods. The gene encoding C. perfringens alpha toxin was detected by PCR (polymerase chain reaction) on formalin-fixed, paraffin-embedded (FFPE) tissues in 20 out of 24 affected lorikeets (83%), but it was not amplified from samples of any of 10 control lorikeets (P < .0001). The second most prevalent C. perfringens toxin gene detected was the beta toxin gene, which was found in FFPE from 7 out of 24 affected lorikeets (29%). The other toxin genes were detected inconsistently and in a relatively low number of samples. These cases seem to be associated with C. perfringens, although the specific type involved could not be determined.

Macroevolutionary bursts and constraints generate a rainbow in a clade of tropical birds.

BACKGROUND: Bird plumage exhibits a diversity of colors that serve functional roles ranging from signaling to camouflage and thermoregulation. However, birds must maintain a balance between evolving colorful signals to attract mates, minimizing conspicuousness to predators, and optimizing adaptation to climate conditions. Examining plumage color macroevolution provides a framework for understanding this dynamic interplay over phylogenetic scales. Plumage evolution due to a single overarching process, such as selection, may generate the same macroevolutionary pattern of color variation across all body regions. In contrast, independent processes may partition plumage and produce region-specific patterns. To test these alternative scenarios, we collected color data from museum specimens of an ornate clade of birds, the Australasian lorikeets, using visible-light and UV-light photography, and comparative methods. We predicted that the diversification of homologous feather regions, i.e., patches, known to be involved in sexual signaling (e.g., face) would be less constrained than patches on the back and wings, where new color states may come at the cost of crypsis. Because environmental adaptation may drive evolution towards or away from color states, we tested whether climate more strongly covaried with plumage regions under greater or weaker macroevolutionary constraint. RESULTS: We found that alternative macroevolutionary models and varying rates best describe color evolution, a pattern consistent with our prediction that different plumage regions evolved in response to independent processes. Modeling plumage regions independently, in functional groups, and all together showed that patches with similar macroevolutionary models clustered together into distinct regions (e.g., head, wing, belly), which suggests that plumage does not evolve as a single trait in this group. Wing patches, which were conserved on a macroevolutionary scale, covaried with climate more strongly than plumage regions (e.g., head), which diversified in a burst. CONCLUSIONS: Overall, our results support the hypothesis that the extraordinary color diversity in the lorikeets was generated by a mosaic of evolutionary processes acting on plumage region subsets. Partitioning of plumage regions in different parts of the body provides a mechanism that allows birds to evolve bright colors for signaling and remain hidden from predators or adapt to local climatic conditions.

HEMATOLOGIC AND PLASMA BIOCHEMICAL REFERENCE VALUES FOR JUVENILE GREEN-NAPED LORIKEETS ( TRICHOGLOSSUS HAEMATODUS HAEMATODUS).

The green-naped lorikeet ( Trichoglossus haematodus haematodus) is a small, brightly colored psittacine that is one of many subspecies of the rainbow lorikeet popular in captivity. Overall, the rainbow lorikeet population is declining but the wide range of subspecies means the population is classified as "least concern" by the International Union for Conservation of Nature. The goal of this study was to establish normal hematologic and plasma biochemical analyte reference intervals for juvenile green-naped lorikeets. Hematology and plasma biochemistry variables were determined for 102 clinically healthy, captive-born, juvenile (2-6 mo) green-naped lorikeets house at a single institution. This study is the first report for hematologic and plasma biochemical values for any Trichoglossus species.

A case of gamasoidosis associated with exposure to a wild lorikeet feeding tray.

Gamasoidosis (acariasis, avian-mite dermatitis or bird-mite dermatitis) is caused by members of the mite superfamily Dermanyssoidea. The mites lay their eggs on the nest of the birds they feed on. The also leave the nest and feed on humans if there is no bird host available. The bites result in urticated plaques and papules. Here we present a case of gamasoidosis from exposure to a wild lorikeet feeding tray.

Comparison of body temperature readings between an implantable microchip and a cloacal probe in lorikeets (Trichoglossus haematodus sp.).

Body temperature readings can be a useful diagnostic tool for identifying the presence of subclinical disease. Traditionally, rectal or cloacal thermometry has been used to obtain body temperatures. The use of implantable microchips to obtain these temperatures has been studied in a variety of animals, but not yet in avian species. Initially, timepoint one (T1), nine lorikeets were anesthetized via facemask induction with 5% isoflurane and maintained at 2-3% for microchip placement and body temperature data collection. Body temperature was measured at 0 and 2 min post-anesthetic induction both cloacally, using a Cardell veterinary monitor and also via implantable microchip, utilizing a universal scanner. On two more occasions, timepoints two and three (T2, T3), the same nine lorikeets were manually restrained to obtain body temperature readings both cloacally and via microchip, again at minutes 0 and 2. There was no statistical difference between body temperatures, for both methods, at T1. Microchip temperatures were statistically different than cloacal temperatures at T2 and T3. Body temperatures at T1, were statistically different from those obtained at T2 and T3 for both methods. Additional studies are warranted to verify the accuracy of microchip core body temperature readings in avian species.

Angiostrongylus dujardini infection in a coconut lorikeet (Trichoglossus haematodus) from a zoological garden in Switzerland.

Angiostrongylus spp. (Metastrongyloidea) can cause severe disease in several animal species and humans. This report describes an infection with Angiostrongylus dujardini in a captive coconut lorikeet (Trichoglossus haematodus) from a zoo in Switzerland. The bird was reported being attacked by conspecifics, removed from the flock, and hospitalized. It showed lethargy, moderately reduced body condition, and lack of reaction to visual stimuli. Analgesic and antibiotic treatment were initiated but because of worsening of its general condition, the bird was euthanized the following day. Necropsy revealed multifocal, subcutaneous hemorrhages, diffusely reddened lungs and a moderately dilated right heart with several intraluminal nematodes embedded in a coagulum. Four worms were collected and microscopically examined. They were identified as adult females, measuring 19-21 mm long x 0.4-0.5 mm wide, with general morphological and morphometric characteristics consistent with angiostrongylid nematodes. In lung sections, multifocal collection of thin-walled embryonated eggs in variable stages of development was observed along with fully developed nematode larvae within the lumina of alveoli and lung vessels. Associated granulomatous infiltrates indicated a severe, multifocal, chronic, granulomatous pneumonia. The diagnosis of A. dujardini infection was formulated by morphological examination of adult and larval stages, supported by molecular analysis (PCR-amplification and sequencing of the ITS2, 5.8S and 28S rDNA flanking regions). This is the first report of A. dujardini infection in an avian species, providing evidence that birds can serve as accidental hosts of this parasite in addition to mammals, and that the parasite can reach maturity and multiply in the avian cardiorespiratory system.

Investigation into clinicopathological and pathological findings, prognosis, and aetiology of lorikeet paralysis syndrome in rainbow lorikeets (Trichoglossus haematodus).

OBJECTIVE: To report the temporal and spatial distribution of rainbow lorikeets presenting with lorikeet paralysis syndrome (LPS) and their clinicopathologic and pathologic findings, exposure to toxins, and response to treatment. METHODS: Records of lorikeets admitted in 2017 and 2018 to facilities in south-east Queensland (QLD) were reviewed and LPS and non-LPS cases were mapped and their distribution compared. Plasma biochemistries and complete blood counts were done on 20 representative lorikeets from south-east QLD and Grafton, New South Wales (NSW). Tissues from 28 lorikeets were examined histologically. Samples were tested for pesticides (n = 19), toxic elements (n = 23), botulism (n = 15) and alcohol (n = 5). RESULTS: LPS occurred in warmer months. Affected lorikeets were found across south-east QLD. Hotspots were identified in Brisbane and the Sunshine Coast. Lorikeets had a heterophilic leucocytosis, elevated muscle enzymes, uric acid and sodium and chloride. Specific lesions were not found. Exposure to cadmium was common in LPS and non-LPS lorikeets. Treated lorikeets had a 60-93% See Table 2 depending on severity of signs. CLINICAL SIGNIFICANCE: The primary differential diagnosis for lorikeets presenting with lower motor neuron signs during spring, summer and autumn in northern NSW and south-east Queensland should be LPS. With supportive care, prognosis is fair to good.

Nectarivorous Bird Emphysematous Ingluvitis (NBEI): A Novel Disease in Loriinae Birds Associated With Clostridium perfringens Infection.

A retrospective study revealed ten cases of emphysematous ingluvitis in Loriinae birds from two zoological collections between 2009 and 2020. Common clinical features were sudden death with gas distention of the crop, subcutaneous cervical emphysema and poor body condition, but also included collapse, hypothermia and abandonment. Macroscopic examination revealed moderate crop enlargement, distention and thickening with minimal intraluminal content, and moderate to severe submucosal to transmural gas-filled cysts (emphysema). Histopathology identified widespread transmural multifocal to coalescing empty pseudo-cystic cavities with lytic necrosis, pyo-/granulomatous inflammatory infiltrates, epithelial ulceration, parakeratotic hyperkeratosis, epithelial ballooning degeneration, and occasional intralesional rod-shaped bacteria. The lesion may have impaired the birds' ability to ingest food, resulting in suboptimal body condition. Necrotizing to granulomatous aspiration pneumonia was also a feature in some cases. Anaerobic bacterial culture of four crops identified Clostridium perfringens with associated toxin genes for alpha and occasionally beta2 toxin (cpa and cpb2 genes respectively), by PCR analysis of bacterial isolates cultured from fresh or frozen tissue. C. perfringens was identified as the common etiological agent of emphysematous ingluvitis in crop and/or liver (six out of ten birds), and type A was confirmed in five birds. C. perfringens was not detected in the crop nor liver of two unaffected Loriinae birds. This is the first publication that characterizes nectarivorous bird emphysematous ingluvitis (NBEI), attributes C. perfringens as an etiological agent, and highlights this novel disease as an important cause of death in Loriinae birds, particularly in nestling and fledgling stage of development, but also in older lorikeets and lories.

Humeral air sac cystadenocarcinoma in a rainbow lorikeet (Trichoglossus moluccanus).

BACKGROUND: A 17-year-old female rainbow lorikeet (Trichoglossus moluccanus) was presented for a swelling over the right proximal humerus and an inability to fly. CASE REPORT: Radiographs revealed a markedly osteoproductive and moderately osteolytic lesion of the proximal left humerus with marked associated soft tissue swelling. Biopsy of the proximal humerus was consistent with an air sac cystadenocarcioma. The bird's condition deteriorated over 25 days after initial presentation and it developed a respiratory wheeze, tail bob, tachypnea and died. On postmortem examination, the bird was found to have an air sac cystadenocarcinoma associated with the proximal humerus, extending into the thoracic cavity through a network of fibrous sheets and displaying infiltration into the lung tissue bilaterally. CONCLUSION: This is the first report of a humeral air sac cystadenocarcinoma in a lorikeet and it builds on our understanding of the species affected by avian neoplasia.

The complete mitogenome of red-collared lorikeet (Trichoglossus rubritorquis) and its phylogenetic analysis.

The complete mitogenome of a lorikeet, Trichoglossus rubritorquis (Psittaciformes, Loriidae), was determined first in the genus Trichoglossus. The assembled mitogenome was 17,915 bp and composed of 13 protein-coding genes, 22 tRNAs, two rRNAs and two control regions. Nucleotide composition of T. rubritorquis mitogenome was 30.20% A, 33.30% C, 14.04% G, and 22.46% T, with an A + T bias of 52.66%. ML tree based on 13 protein-coding genes indicated that, Melopsittacus undulatus of the family Psittacidae was the closest related species to T. rubritorquis. This result suggested that lorikeets might still be in the family Psittacidae.