Macroscopic, cytological and histological diagnosis of proventricular adenocarcinoma in a sulphur-crested cockatoo (Cacatua galerita).

An adult sulphur-crested cockatoo (Cacatua galerita) was unexpectedly found dead and was presented for post-mortem examination. Macroscopically, the proventricular wall was expanded by an infiltrative off-white mass, 10 mm in diameter, with secondary mucosal ulceration. Cytological examination of impression smears revealed a neoplastic epithelial cell population forming occasional well-defined acini with secretory product. Histologically, the neoplastic cells were predominantly arranged in acini and tubules, with fewer in small clusters, supported by a desmoplastic stroma. Neoplastic cells were polygonal, with mostly well-demarcated cell boundaries and a moderate amount of eosinophilic cytoplasm that was multifocally markedly distended by more intensely eosinophilic material. There was an increased nuclear-to-cytoplasmic ratio with moderately sized to large nuclei (approximately 15 µm diameter) with lightly to densely stippled chromatin and single or paired prominent basophilic nucleoli. The mitotic count was 19 in 10 high-power fields (2.37 mm2), with scattered bizarre mitotic figures and atypia including moderate anisocytosis and anisokaryosis and moderate cellular and nuclear pleomorphism. There was frequent intratubular brightly eosinophilic proteinaceous material, which was Alcian blue and periodic acid‒Schiff positive. Proventricular lymphovascular invasion was detected, with metastases within the ventriculus and lungs. The macroscopic, cytological and histological appearance of the neoplasm was consistent with a proventricular adenocarcinoma.

Visceral Haemoproteus minutus Infection in a Major Mitchell's Cockatoo (Lophochroa leadbeateri).

A 1-year-old major Mitchell's cockatoo (Lophochroa leadbeateri) was presented for evaluation of weakness, diarrhea with undigested seeds in the droppings, and weight loss. Leukocytosis with severe heterophilia, monocytosis, and lymphocytosis was noted on the complete blood count. Altered plasma biochemical parameters included a slight increase in creatine kinase and mild hypoproteinemia. Two blood smears before and after 2 days of treatment revealed mild polychromasia and anisocytosis but no blood parasites. Radiographic and computed tomographic imaging of the cockatoo were helpful in identifying airsacculitis, pneumonia, and gastrointestinal motility disorders. The patient died 5 days after treatment for the presenting clinical problems. On the gross postmortem examination, dark red foci in the ventricular muscle layers and 1-3-mm white foci in the myocardium, opaque air sacs, and dark lungs were identified. Histopathologic examination of submitted tissue samples found severe granulomatous ventriculitis and myocarditis with intralesional Haemoproteus species megalomeronts. Qualitative polymerase chain reaction testing for the cytochrome b (cyt b) gene performed on pooled heart, liver, kidney, and intestinal tissues identified 99.5% homology to Haemoproteus minutus. This case report demonstrates the expansion of the geographic range of H minutus to France and potentially to Belgium, which may compromise breeding and conservation of Australian parrots living outdoors. Challenging diagnosis, rapid disease progression, and the absence of validated treatment protocols for psittacine patients suggest that the use of preventive measures to reduce the presence of insect vectors such as hippoboscid flies and biting midges (Culicoides) should be considered. Haemoproteus minutus should be considered and potentially screened by polymerase chain reaction testing on blood samples, especially in the case of highly susceptible avian species (eg, Australian parrots in Europe) that present with sudden weakness, heterophilic leukocytosis, and monocytosis associated with mild anemia.

Bilateral Cubital Lymphoma and Mycobacteriosis in a Salmon-Crested Cockatoo (Cacatua moluccensis).

A 32-year-old male salmon-crested cockatoo (Cacatua moluccensis) was diagnosed by cytology with bilateral cubital lymphoma and mycobacteriosis. Polymerase chain reaction assay testing confirmed Mycobacterium genavense. This patient was subsequently humanely euthanized. Postmortem histopathology confirmed both diagnoses with findings of multicentric lymphoma, acid-fast bacilli, and severe degenerative changes in all synovial joints examined. Immunohistochemical staining for paired box protein 5 of the cubital mass was positive for a high percentage of B-cell lymphocytes, consistent with B-cell lymphoma. This unusual case of two major diseases presenting concurrently in one patient raises the question of whether the pathogenesis could have an interdependent relationship. Mycobacteriosis, severe degenerative joint changes, or both may have stimulated lymphocytes, eventually leading to lymphoma. Additional screening and monitoring for comorbidities may be advised if 1 of these diseases are diagnosed in companion avian species.

Flexible tool set transport in Goffin's cockatoos.

The use of tool sets constitutes one of the most elaborate examples of animal technology, and reports of it in nature are limited to chimpanzees and Goffin's cockatoos. Although tool set use in Goffin's was only recently discovered, we know that chimpanzees flexibly transport tool sets, depending on their need. Flexible tool set transport can be considered full evidence for identification of a genuine tool set, as the selection of the second tool is not just a response to the outcomes of the use of the first tool but implies recognizing the need for both tools before using any of them (thus, categorizing both tools together as a tool set). In three controlled experiments, we tested captive Goffin's in tasks inspired by the termite fishing of Goualougo Triangle's chimpanzees. Thereby, we show that some Goffin's can innovate the use and flexibly use and transport a new tool set for immediate future use; therefore, their sequential tool use is more than the sum of its parts. VIDEO ABSTRACT.

Reproductive status of a female white cockatoo (Cacatua alba) based on relationships among urofecal steroid hormone dynamics, molting, and body weight.

The detailed reproductive physiology of cockatoos based on gonadal hormone dynamics is unclear. In this study, we aimed to investigate ovarian activity by monitoring urofecal sex steroid hormone profiles in a captive female white cockatoo (Cacatua alba) and to noninvasively reveal basic reproductive physiology by comparing the hormone profiles with the laying dates, body mass changes, and molt progress. Urofeces were collected regularly for approximately 4 years from one female that frequently laid unfertilized eggs under single-rearing conditions. Urofecal progesterone (P4) and estradiol-17ß (E2) were measured by enzyme immunoassay. In addition, body mass and the number of fallen feathers were measured periodically. The urofecal P4 concentration peaked at an average of 17.7 days after the start of the rise in urofecal E2 concentration, and egg laying began on the day after the peak urofecal P4 concentration. The clutch size was usually two eggs, with an average interval of 4.5 days between eggs in each egg-laying cycle. There was a significant correlation between the dynamics of E2 concentration in urofeces and body mass. The results strongly suggest that E2 and P4 reflect the follicle growth and ovulation status, respectively, and that noninvasive monitoring of hormone dynamics using urofeces can accurately capture ovarian activity in the white cockatoo. Furthermore, changes in body mass can predict follicular growth, and reproduction and molt are antagonistic.

Cryptococcal Meningitis in an Immunocompetent Man Exposed to a Pet Cockatoo: An Overlooked Zoonosis.

Cryptococcus species are commonly isolated in the excreta of birds, but zoonotic transmission has yet to be proven. We report a case of an immunocompetent man with meningitis caused by Cryptococcus neoformans var. grubii with significant exposure to a pet cockatoo highly suspicious for zoonotic transmission. Treatment with intravenous liposomal amphotericin B and oral flucytosine was initiated upon diagnosis, but diagnostic delay because of low suspicion contributed to neurological sequelae. Recognition of pet birds as potential sources of Cryptococcus species' zoonotic transmission is essential for prompt diagnosis and treatment.

Implications of wild cockatoos manufacturing and using tools.

O'Hara et al. (Current Biology, 31, 4512-4520, 2021) show that wild Goffin's cockatoos (Cacatua goffiniana) exhibit tool-related abilities at levels previously demonstrated by nonhuman primates or, in birds, only by those raised in captivity. Their data provide information about the cognitive and ecological underpinnings of this behavior and provide the impetus to search for additional examples of convergent evolution in avian and mammalian lines.

Wild Goffin's cockatoos flexibly manufacture and use tool sets.

The use of different tools to achieve a single goal is considered unique to human and primate technology. To unravel the origins of such complex behaviors, it is crucial to investigate tool use that is not necessary for a species' survival. These cases can be assumed to have emerged innovatively and be applied flexibly, thus emphasizing creativity and intelligence. However, it is intrinsically challenging to record tool innovations in natural settings that do not occur species-wide. Here, we report the discovery of two distinct tool manufacture methods and the use of tool sets in wild Goffin's cockatoos (Cacatua goffiniana). Up to three types of wooden tools, differing in their physical properties and each serving a different function, were manufactured and employed to extract embedded seed matter of Cerbera manghas. While Goffin's cockatoos do not depend on tool-obtained resources, repeated observations of two temporarily captive wild birds and indications from free-ranging individuals suggest this behavior occurs in the wild, albeit not species-wide. The use of a tool set in a non-primate implies convergent evolution of advanced tool use. Furthermore, these observations demonstrate how a species without hands can achieve dexterity in a high-precision task. The presence of flexible use and manufacture of tool sets in animals distantly related to humans significantly diversifies the phylogenetic landscape of technology and opens multiple avenues for future research. VIDEO ABSTRACT.

Goffin's Cockatoos (Cacatua goffiniana) Can Solve a Novel Problem After Conflicting Past Experiences.

Novel problems often partially overlap with familiar ones. Some features match the qualities of previous situations stored in long-term memory and therefore trigger their retrieval. Using relevant, while inhibiting irrelevant, memories to solve novel problems is a hallmark of behavioral flexibility in humans and has recently been demonstrated in great apes. This capacity has been proposed to promote technical innovativeness and thus warrants investigations of such a mechanism in other innovative species. Here, we show that proficient tool-users among Goffin's cockatoos-an innovative tool-using species-could use a relevant previous experience to solve a novel, partially overlapping problem, even despite a conflicting, potentially misleading, experience. This suggests that selecting relevant experiences over irrelevant experiences guides problem solving at least in some Goffin's cockatoos. Our result supports the hypothesis that flexible memory functions may promote technical innovations.

Does captivity alter problem-solving behavior in Goffin's cockatoos?

Researchers often argue for the existence of "captivity bias": a higher success rate that may be observed for nonhumans tested in captivity compared to those tested in nature, purportedly because the former have certain advantages that the latter lack. Rössler et al. (Scientific Reports 10, 8681, 2020) find that, at least for Goffin's cockatoos (Cacatua goffiniana), differences exist in motivation, not in problem-solving ability.

Cloacal Diseases in Companion Parrots: A Retrospective Study of 43 Cases (2012-2018).

Cloacal disease is considered a common presenting complaint in companion parrots. The purpose of this study was to better characterize the prevalence of cloacal disease within a population of owned psittacine birds. Medical records of all owned parrots presented to an exotic animal specialty service between July 2012 and January 2018 were retrospectively reviewed for the presence of cloacal disease. Cloacal disease was identified in 43 of 1137 cases (3.8%). Cockatoos presented with cloacal disease significantly more often than other psittacine groups (P < .001). Female parrots presented with cloacal disease significantly more often than males and unsexed birds (P < .001). Cockatoos with cloacal disease predominantly presented with prolapse of the cloaca itself (P = .006). There was no significant difference in outcome based on taxonomic group, sex, or primary cloacal pathology. Prospective studies with parrot species are encouraged to have an increased understanding of the behavioral and medical conditions that result in cloacal disease. These studies would hopefully facilitate the development of better treatment options for this relatively common disease presentation.

Asymmetrical Cloacoplasty for the Treatment of Chronic Cloacal Prolapse in Psittaciformes: A Case Series.

Chronic cloacal prolapse is a common condition in psittacine birds, particularly in cockatoos and African grey parrots (Psittacus erithacus). Techniques to permanently reduce the prolapse have been developed and include cloacal sutures, percutaneous cloacopexy, and open circumcostal or rib cloacopexy. Several complications, some of which are life-threatening, have been reported with these tissue reduction techniques. Cloacoplasty surgeries have also been advocated, but most often as an adjunct therapy. Recurrence of cloacal prolapse may occur in traditional symmetrical cloacoplasty techniques since straining pressure remains. In this case series, 5 psittacine birds (2 male and 2 female umbrella cockatoos [Cacatua alba] and 1 male African grey parrot) with chronic recurrent cloacal prolapses were treated with a novel asymmetrical cloacoplasty technique. A semicircular excision at the mucocutaneous junction from the right side with a 2-layer closure reduced the cloacal opening by 50%-75%. A tension-relieving suture was applied to aid in healing of the incision. All 5 cases had successful outcomes with no recurrent prolapses (6 months to 3 years of follow-up), except for 1 case, due to incisional dehiscence. This animal underwent a second surgical procedure that incorporated the tension-relieving suture and has not had a recurrent prolapse in over a year. This asymmetrical cloacoplasty technique provides a simple but effective method of cloacal prolapse treatment and prevention in cases of recurrent and chronic cloacal prolapses, and creates a midline physical barrier not present in symmetrical cloacoplasties. Long-term complications may include cloacolith formation or dystocia in females, and therefore reproductive management of female birds is required.

Horner Syndrome With Ipsilateral Wing Paresis in a Wild, Juvenile Yellow-Tailed Black Cockatoo (Calyptorhynchus funereus).

A juvenile yellow-tailed black cockatoo (Calyptorhynchus funereus) was presented with paresis of the right wing, ptosis, and miosis of the right eye; feather erection of the right side of the head and neck; and a penetrating injury over the right pectoral muscle. Temporary reversal of ptosis, miosis, and feather erection after administration of phenylephrine drops confirmed a diagnosis of Horner syndrome. Computed tomographic imaging revealed a fractured rib, traumatic lung lesions, and subcutaneous emphysema. The right-sided Horner syndrome and wing paresis were attributed to a sympathetic nerve trauma of the eye and feathers and to the brachial plexus, respectively. This report describes the diagnosis and resolution of ptosis and miosis within 8 weeks and recovery of feather symmetry and wing function within 11 weeks of the cockatoo's initial presentation with a conservative-management treatment plan.

Treatment of Exuberant Granulation Tissue in an Umbrella Cockatoo (Cacatua alba) with Strontium Radiation.

A 26-year-old female umbrella cockatoo (Cacatua alba) was presented for reoccurrence of a soft tissue mass extending from a fractured area of the rhinotheca. The mass was originally observed 12 years before, after unknown trauma. Histopathology after initial removal was consistent with inflammatory granulation tissue. The mass reoccurred 3 additional times in the same location despite surgical removal and cryogenic therapy. On the fourth surgical resection, strontium-90 radiotherapy was applied to the site immediately after the surgical procedure. No recurrence of the tissue mass from this location has been observed for almost 2 years. This case demonstrates the novel use of strontium radiotherapy to treat exuberant granulation tissue in a bird.

HINDLIMB PARALYSIS SYNDROME IN WILD CARNABY'S COCKATOOS (CALYPTORHYNCHUS LATIROSTRIS): A NEW THREAT FOR AN ENDANGERED SPECIES.

Carnaby's Cockatoos (Calyptorhynchus latirostris) are in decline in SW Western Australia from several processes, including habitat loss and fragmentation. However, in recent years, a disease syndrome has also emerged as a significant population threat. Emerging diseases in wildlife have the potential for catastrophic effects on population numbers, especially if a species is experiencing existing pressure from other threatening processes. This article describes an investigation into a hindlimb paralysis syndrome that has occurred in the summer and autumn since 2012 in 84 wild Carnaby's Cockatoos. Recovery from the syndrome has been demonstrated in 21 of 33 cases when supportive therapy was applied. Although a definitive diagnosis has not been obtained, the hypothesized etiology is an organophosphate-induced delayed-onset neuropathy. The syndrome may indicate that interaction between the cockatoos and inland agricultural practices are affecting this migratory species in ways that are, so far, poorly understood.

Vegetative Endocarditis due to Staphylococcus aureus in an Umbrella Cockatoo (Cacatua alba).

A 15-year-old, female cockatoo (Cacatua alba) was presented with a history of intermittent cloacal prolapse of 1-year duration. After each prolapse, the owner would digitally reduce the distended cloacal tissue within approximately 12-24 hours, for short-term resolution. The cockatoo was examined 3 times over a 7-month period and received supportive care with leuprolide acetate, behavioral modification, and diet change. After the third examination, the owner decided to proceed with a surgical cloacopexy. Five days after the last examination and before the procedure was scheduled, the cockatoo was reexamined for acute onset of weakness, anorexia, lethargy, and right-leg paresis. Despite supportive treatment, the cockatoo's clinical condition declined, and it went into respiratory arrest. Resuscitative efforts, including manual ventilation and cardiovascular support, were unsuccessful, and the bird died. Results of postmortem examination revealed vegetative endocarditis with intralesional bacteria cultured as Staphylococcus aureus, right-hindlimb myonecrosis, hepatitis, and nephritis. We suspect that the source of the hematogenous S aureus infection in this cockatoo was translocation from the owner's skin from the repeated manual manipulation and replacement of the prolapsed cloacal tissue.

Inclusion of Madagascar cockroach (Gromphadorhina portentosa) meal in the diet of cockatiels (Nymphicus hollandicus) in captivity: Influences on offspring development.

The use of unconventional food for animals is becoming more common. The objective was to evaluate the inclusion of Madagascar cockroach (Gromphadorhina portentosa) meal in the diet of cockatiel (Nymphicus hollandicus) chicks in captivity. Twenty-eight cockatiel chicks were used during 90 days of experiment. The animals were divided into two groups: a control group (receiving commercial feed + seed mixture) and a test group (receiving a control diet supplemented with Madagascar cockroach meal). The cockroach meal was mixed into commercial feed at a ratio of 14:1 (commercial feed: cockroach meal; 6.6% inclusion). Parents of the chicks were fed the experimental diets 30 days before egg laying to evaluate the influence of the cockroach meal on offspring development in the nest (1 to 30 days of age). Body development of the birds was evaluated every three days from the first to the 30th day of age and then every 15 days from the 31st to the 90th day of age. The cockroach meal did not influence (P > .05) the growth characteristics, body weight, total length or length of the animal's beaks, wings or tails, but increased seed consumption from the 31st to the 90th day of age. It is concluded that the cockroach meal can be used in the diet of growing cockatiels at an addition level of 6.6%.

Reproductive Characteristics of Cockatiels (Nymphicus hollandicus) Maintained in Captivityand Receiving Madagascar Cockroach (Gromphadorhina portentosa) Meal.

The aim of this study was to evaluate the use of a Madagascar cockroach (Gromphadorhina portentosa) meal in the feed of cockatiels (Nymphicus hollandicus) in captivity and its influence on the reproductive characteristics of these birds. Twelve pairs of birds were used during two subsequent reproductive cycles of 130 days each, with time divided into four phases: laying, incubation, rearing of chicks until 30 days of age, and return to the new laying phase. The pairs were divided into two groups: a control group, which received a commercial diet for psittacines + a mixture of seeds, and a test group, which received the same diet as the control group except for the addition of a Madagascar cockroach meal in a ratio of 14 g of commercial food to 1 g of cockroach meal (6.6%). After hatching, chicks remained with their parents until 30 days of age. Subsequently, the chicks were transferred to another room and monitored until the 90th day of life. The inclusion of cockroach meal did not influence (p > 0.05) the intake of commercial food and mixture of seeds during the reproductive phases evaluated, except for feed intake, which was increased relative to control values (p = 0.02) in the return-to-laying phase. Yolk cholesterol content, egg width and egg shape index were increased with the inclusion of the cockroach meal, whereas the number of days to return to the new laying phase was reduced compared to the control (p = 0.02). The number of eggs laid decreased (p < 0.05) with the inclusion of the cockroach meal; however, the percentage of hatching was higher in the test group than in the control group (p < 0.05). No significant effect (p > 0.05) of dietary treatment was observed on the number of viable chicks at 1, 30 and 90 days of age or on the contents of most fatty acids present in the yolk. The findings of this study indicate that a Madagascar cockroach meal can be used as an alternative feedstuff in the diets for cockatiels and can lead to minor improvements in reproductive characteristics when replacing 6.6% of the commercial pelleted diet.

Infraorbital Keratin Cyst in an Umbrella Cockatoo (Cacatua alba).

A 10-year-old, female umbrella cockatoo (Cacatua alba) was presented for evaluation of a mass at the right commissure of the beak, with associated right periorbital swelling. A feather cyst was suspected, based on history and the results of a computed tomography scan and fine-needle aspirate. The cyst was surgically debrided and removed. Histopathologic results confirmed an infraorbital keratin cyst, most likely originating from a feather follicle. To our knowledge, this is the first reported case of a periorbital keratin cyst in a bird.

Rectricectomy With Pygostylectomy for Resolution of Feather Trauma in an Umbrella Cockatoo (Cacatua alba).

Feather trauma is a common problem among pet birds, especially those with trimmed wing feathers, and often affects remiges and rectrices. Damage can become chronic if new feathers remain unprotected by fully formed adjacent feathers. The follicles can become damaged and poorly functional over time. A 6-month-old male umbrella cockatoo (Cacatua alba) was presented for examination because of feather damage that occurred shortly after receiving a wing trim by the owner. Over the next 18 months, various medical, behavioral, and husbandry methods failed to allow normal regrowth of the tail feathers. The bird presented 25 times over the 18-month period for problems associated with broken blood feathers in the tail. Feather imping was ruled out because of the lack of hollow adult shafts to serve as a base. Diagnostic tests included hematologic testing and biochemical analysis, circovirus testing, feather biopsy, and radiographs, results of which were unremarkable. Because of the chronic pain associated with the frequent rectrix damage, a complete rectricectomy was performed. All of the rectrical follicles as well as the pygostyle were surgically removed. Healing was uneventful and the bird has been clinically normal with no further blood feather injury for 24 months after surgery.