Isolation and Genetic Characterization of a Novel Adenovirus Associated with Mass Mortality in Great Cormorants (Phalacrocorax carbo).

High mortality in great cormorants (Phalacrocorax carbo) was registered on the Alakol Lake in eastern Kazakhstan in 2021 when about 20% of juveniles died. High-throughput sequencing revealed the presence of a putative novel cormorant adenovirus significantly divergent from known aviadenoviruses. We suggest that this cormorant adenovirus can be considered an emerging threat to the health and conservation of this species.

Aislamiento y caracterización genética de un nuevo adenovirus asociado con la mortalidad masiva en cormoranes grandes (Phalacrocorax carbo). En 2021 se registró una alta mortalidad de cormoranes grandes (Phalacrocorax carbo) en el lago Alakol, en el este de Kazajstán, cuando murieron alrededor del 20% de las aves jóvenes. La secuenciación de alto rendimiento reveló la presencia de un supuesto nuevo adenovirus de cormorán significativamente divergente de los aviadenovirus conocidos. Sugerimos que este adenovirus de cormorán puede considerarse una amenaza emergente para la salud y conservación de esta especie.

Causes of Fatal Cyathostomiasis in Brown Booby (Sula leucogaster) from Brazil: Identification of Pathogen and Implications for Management.

Fatal infection by Cyathostoma (Cyathostoma) phenisci (Nematoda: Syngamidae), was identified in 2 of 52 brown boobies (Sula leucogaster) collected on beaches in the state of Rio de Janeiro, Brazil, and admitted to the veterinary clinic for rehabilitation. Both infected birds were in poor physical condition, with atrophied pectoral muscles, and died soon after starting treatment. The parasitological and pathological examination of the carcasses revealed the presence of C. (C.) phenisci in the trachea, resulting in tracheitis, as well as severe parasitic granulomatous bronchopneumonia caused by eggs deposited in the lungs. In our opinion, these serious pathological changes were the primary cause of chronic respiratory illness. This is the first description of fatal cyathostomiasis in a fish-eating avian host caused by infection by a member of the subgenus Cyathostoma (Cyathostoma). Therefore, it is reasonable to consider C. (C.) phenisci to be a real threat to a wide range of their definitive hosts, and cyathostomiasis should be considered in the differential diagnosis for fish-eating marine birds, even in cases without respiratory signs. This is also the first record of the genus Cyathostoma in Brazil.

Avian Gastric Yeast (Macrorhabdus ornithogaster) and Mycobacterium genavense Infections in a Zoo Budgerigar (Melopsittacus undulatus) Flock.

Over a 4-mo period, a Michigan zoo had 32 budgerigars, Melopsittacus undulatus, from their flock die. Whole animals or formalin-fixed tissues were submitted to Michigan State University Veterinary Diagnostic Laboratory for diagnosis. Avian gastric yeast infection, Macrorhabdus ornithogaster, was diagnosed in seven birds. There was atrophy of breast musculature and no subcutaneous or coelomic fat stores in six necropsied birds. Only two birds had proventricular dilatation grossly. Histologic examination of the proventriculus of all seven birds revealed abundant 3 × 50-µm septate, parallel-walled, nonbranching yeast organisms morphologically consistent with Macrorhabdus ornithogaster. Mycobacteriosis was diagnosed in three budgerigars, two of which were necropsied. Both necropsied birds had hepatomegaly and one also had splenomegaly. No acid-fast bacilli were found in the livers of either bird but were found in splenic macrophages of the bird with splenomegaly and in the intestine of the other bird. Mycobacterium species were cultured from the enlarged spleen and identified by DNA sequence as Mycobacterium genavense. Pulmonary granulomas with acid-fast bacilli were found in the bird submitted as fixed tissues. None of the budgerigars had a dual infection. The remainder of the budgerigars died from hepatitis, nephrosis, oviductal prolapse, exclusion from food and water by flock mates, or tumors.

RETROSPECTIVE STUDY OF CAUSES OF ANIMAL MORTALITY IN LJUBLJANA ZOO 2005-2015.

Zoos harbor large collections of diverse species, aiding in both conservation and education, as well as research in multiple scientific fields. However, the most common causes of death in zoo animals around the world remain unclear because few extensive reports or reviews are published on this topic. This information could greatly improve preventive veterinary medicine in zoologic gardens. This study provides a retrospective overview of the causes of death of animals from the Ljubljana Zoo in the years 2005-2015. During this period, a total of 353 animals were submitted for necropsy, of which 244 were mammals, 85 were birds, and 25 were reptiles. The causes of deaths were divided into infectious diseases (38%), dysfunctions of individual organs (20%), traumas (13%), parasitosis (7%), reproductive disorders (6%), metabolic disorders (3%), neoplastic disease (4%), and intoxications (4%). In some cases, the cause of death was unable to be determined (7%), most commonly because of autolysis of the body. The results of this retrospective study bring a general overview of the epizootiologic situation in the Ljubljana Zoo over an 11-yr period and valuable information to other zoos to optimize preventative plans and diagnostics.

Horner Syndrome in Birds of Prey.

Horner syndrome, which results from oculosympathetic denervation, has rarely been reported in birds. A retrospective study was conducted in a raptor rehabilitation program to gain further insight into Horner syndrome in birds. Data from 5128 live raptors admitted over 20 years were reviewed. Horner syndrome was identified in 22 individuals from 13 different species. Raptors from the orders Strigiformes, Accipitriformes, and Falconiformes were affected, with the last order being underrepresented. Ptosis of the upper eyelid was the most commonly reported clinical sign in the birds diagnosed with Horner syndrome, having been noted in 21 cases. Signs of traumatic injury, such as fractures, wounds, and hematomas, were documented in 18 cases. Among the 22 cases, 12 birds were euthanatized, 3 died in treatment, and 7 were successfully released back into the wild.

Qualitative identification of imidacloprid in postmortem animal tissue by gas chromatography-tandem mass spectrometry.

During an avian mass mortality event investigation at the National Fish and Wildlife Forensic Laboratory in Ashland, OR, imidacloprid became an insecticide of concern. A qualitative analytical toxicology screen of seeds, plucks (tongue, esophagus, and trachea), and ventricular contents was requested. A method for the extraction and qualitative analysis of the insecticide in animal tissues was therefore developed. The procedure relies on a combined Food Emergency Response Network (FERN) and QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) approach to sample extraction followed by qualitative analysis by gas chromatography-tandem mass spectrometry. Since imidacloprid is not amenable to the conditions of gas chromatography, a trimethylsilyl derivative was created and characterized. Proposed mechanisms for the creation of this derivative and its mass spectrum are described. The imidacloprid-trimethylsilyl (TMS) derivative was detected in all samples submitted.

Typhlohepatitis and Amyloidosis Associated with High Mortality in Chukar Partridges (Alectoris chukar).

Twelve chukar partridges (Alectoris chukar) from a farm experiencing poor uniformity and increased mortality of up to 65% were submitted for diagnosis. Several birds had mild to moderate multifocal white foci or multifocal petechial hemorrhages throughout the liver. Livers and spleens of older birds were moderate to severely diffusely enlarged. In addition, some birds had caseous cores mixed with blood within the ceca as well as segmentally thickened cecal walls. Histopathology showed acute, multifocal, severe, often coalescing foci of necrosis with accumulation of fibrin and/or fibrinosuppurative inflammation in livers and spleens. Scattered within exudate were protozoa that were spherical or round and measured 12-20 µm in diameter. In the ceca, acute necrosis of the mucosa was observed, often with ulceration and fibrinosuppurative inflammation. Immunohistochemistry using an antiserum against Tritrichomonas foetus revealed round protozoa in ceca, small intestines, liver, spleen, and lung. Quantitative PCR to detect DNA of Histomonas meleagridis was negative. Non-species-specific PCRs amplifying the partial rDNA, the internal transcribed spacer (ITS) region, and the partial beta-tubulin gene yielded products of the expected size. Sequences of the PCR products had the highest homology to sequences of Tetratrichomonas gallinarum and less homology to sequences of H. meleagridis. In addition there was accumulation of amyloid in the space of Disse in the liver, splenic sinuses, and walls of the blood vessels. The typhlohepatitis and other inflammatory processes that were diagnosed might be the underlying cause of the amyloidosis. Other findings were clusters of Clostridium perfringens associated with the lesions in the ceca; multifocal granulomas in the lungs, occasionally associated with fungal hyphae; hyperkeratosis associated with bacteria and Candida sp. cells in the crop; mild infection of the bursal mucosa with Cryptosporidium.

Tiflohepatitis y amiloidosis asociadas con alta mortalidad en perdices chukar (Alectoris chukar). Doce perdices chukar (Alectoris chukar) de una granja con baja uniformidad y alta mortalidad de hasta el 65% se presentaron para diagnóstico. Varias aves presentaron áreas blancas multifocales de leves a moderadas o hemorragias petequiales multifocales en todo el hígado. Los hígados y los bazos de las aves con mayor edad estuvieron agrandados de tamaño de manera difusa y de moderado a severo. Además, algunas aves tenían contenidos caseosos mezclados con sangre dentro de los ciegos, así como paredes cecales engrosadas de manera segmentaria. La histopatología mostró focos de necrosis agudos, multifocales, graves, a menudo coalescentes con acumulación de fibrina y/o inflamación fibrinosupurativa en hígados y bazos. Dispersos dentro del exudado se encontraban protozoarios que eran esféricos o redondos y que medían de 12 a 20 µm de diámetro. En el ciego, se observó necrosis aguda de la mucosa, a menudo con ulceración e inflamación fibrinosupurativa. La inmunohistoquímica con un antisuero contra Tritrichomonas foetus reveló protozoarios redondos en el ciego, intestino delgado, hígado, bazo y pulmón. El método de PCR cuantitativo para detectar el ADN de Histomonas meleagridis fue negativo. Los métodos de PCR no específicos de especie que amplifican parcialmente al rDNA de la región espaciadora transcrita interna (ITS) y el gene parcial de la beta-tubulina dieron productos del tamaño esperado. Las secuencias de los productos de PCR tuvieron la mayor similitud con las secuencias de Tetratrichomonas gallinarum y menos similitud con las secuencias de H. meleagridis. Además, se observó acumulación de amiloide en el espacio de Disse en el hígado, en senos esplénicos y paredes de los vasos sanguíneos. La tiflohepatitis y otros procesos inflamatorios que se diagnosticaron pueden ser la causa subyacente de la amiloidosis. Otros hallazgos incluyeron grupos de Clostridium perfringens asociados con las lesiones en el ciego; granulomas multifocales en los pulmones, ocasionalmente asociados con hifas fúngicas; hiperqueratosis asociada a bacterias y Candida spp. en el buche, e infección leve de la mucosa bursal con Cryptosporidium.

HISTOPATHOLOGIC FINDINGS IN FREE-RANGING CALIFORNIA HUMMINGBIRDS, 1996-2017.

A histopathologic study of free-ranging hummingbirds found in California, US was performed to identify mortality trends. Tissues from 61 wild hummingbirds representing five native California species collected by the San Diego Zoo from 1996 to 2016 or the Lindsay Wildlife Experience from 2015 to 2017 were histologically examined. Birds were either found dead or moribund at the time of submission or were euthanized due to unresolvable health issues. Long-term rehabilitated birds were excluded from this study. Lesions were sorted by organ, etiology, and gender. The most commonly affected organs were the lung (68%, 40/59), followed by the ingluvies (67%, 34/51) and the liver (54%, 33/61). While some birds had minimal or nonspecific lesions, 23% (14/61) had lesions primarily attributable to trauma, 16% (10/61) had lesions associated with bacteria, fungi, or viruses, 11% (7/61) had parasitic lesions, and 13% (8/61) had multifactorial concurrent processes. Infectious disease lesions included those associated with avian poxvirus, intestinal adenovirus, disseminated aspergillosis, bacterial septicemia, malaria ( Haemoproteus spp.), and mycobacteriosis. The most commonly identified parasitic infection was intestinal cestodiasis, for which there was no significant associated intestinal damage, although the large size of these cestodes may have affected digestion. The incidence of traumatic lesions did not vary significantly by sex, age, species, or sampling location. Other significant findings not related to disease or trauma, but not previously documented, were histologic evidence of a gallbladder and the presence of aortic ossification. Our study reported mortality trends at a population level for free-ranging hummingbirds found in California and identified the presence of intestinal adenovirus and two anatomic structures not previously described.

Clinical features, treatment, and outcomes of cutaneous and oral squamous cell carcinoma in avian species.

OBJECTIVE To determine the clinical features, treatment, and outcomes of treatment for oral and cutaneous squamous cell carcinoma (SCC) in avian species. DESIGN Retrospective case series with nested cohort study. ANIMALS 87 client-owned birds of various species with histologically confirmed SCC of the skin or oral cavity. PROCEDURES Clinicians entered case information through an online survey tool. Data were collected regarding patient signalment, concurrent conditions, treatments, adverse effects, and clinical outcomes. Relationships were examined between complete excision and partial or complete response. Survival analysis was performed to compare outcomes among groupings of therapeutic approaches. RESULTS Only 7 of 64 (11%) birds for which full outcome data were available had complete remission of SCC; 53 (83%) had progressive disease, were euthanized, or died of the disease. The unadjusted OR for partial or complete response following complete tumor excision (vs other treatment approaches) was 6.9 (95% confidence interval [CI], 1.8 to 25.8). Risk of death was 62% lower (hazard ratio, 0.38; 95% CI, 0.19 to 0.77) for birds that underwent complete excision versus conservative treatment. Median survival time from initial evaluation for birds receiving complete excision was 628 days (95% CI, 210 to 1,008 days), compared with 171 days (95% CI, 89 to 286 days) for birds receiving monitoring with or without conservative treatment. Birds receiving any other additional treatment had a median survival time of 357 days (95% CI, 143 to 562 days). CONCLUSIONS AND CLINICAL RELEVANCE For birds with SCC, complete excision was the only treatment approach significantly associated with complete or partial response and increased survival time.

Mass Mortality Attributed to Acanthocephaliasis at a Gull-billed Tern (Gelochelidon nilotica) Colony in Coastal California, USA.

From 12 May 2013 to 29 May 2013, the Gull-billed Tern (Gelochelidon nilotica) colony at the San Diego Bay National Wildlife Refuge, California, US, experienced a mass die-off of at least 92 adults, representing 71-92% of the breeding population on the US west coast. Cause of death was determined to be peritonitis due to perforations of the intestine by a large quantity of acanthocephala (Profilicollis [=Polymorphus] altmani). This is a unique report of P. altmani infecting G. nilotica, and a report of a great impact to a tern population in southern California. Mole crabs (Emerita analoga), the intermediate host for P. altmani and a major component of the Gull-billed Tern diet in San Diego, were found in the stomachs of necropsied terns along with cystacanths, and are the presumed source of the parasite infection. The tern's dietary reliance upon mole crabs likely amplified parasite transmission and infection. We suggest additional research to determine factors that influence parasite infection of intermediate and definitive hosts, particularly mole crabs, given that they are a vital resource for migrating birds within the coastal zone.

Acute, Fatal, Presumptive Xylitol Toxicosis in Cape Sugarbirds ( Promerops cafer).

Twenty-nine wild Cape sugarbirds ( Promerops cafer) died acutely after ingestion of a homemade xylitol nectar solution from a bird feeder. The most aggressive feeders were first affected. Most birds showed clinical signs within 15 minutes of nectar ingestion, including incoordination, weakness, falling from perches, collapse, and death. A few birds showing clinical signs seemed to spontaneously recover and fly away. Full necropsy examinations done on 27 birds were hampered by freezing artifact and autolysis, but results indicated death was caused by the consequences of acute hypoglycemia. A presumptive diagnosis of xylitol toxicity was made based on the history, clinical signs, and absence of other obvious causes of death. This is potentially the first record of xylitol toxicity in wild birds.

Outbreak of an Unusual Tracheal Mite, Ptilonyssus morofskyi (Acarina: Rhinonyssidae), in Canaries ( Serinus canaria ) With Concurrent Infection With Staphylococcus aureus and Macrorhabdus ornithogaster.

Mortalities in a flock of canaries ( Serinus canaria ) with respiratory acariasis, pododermatitis caused by Staphylococcus aureus , and macrorhabdosis were investigated by postmortem examination. After a thorough parasitologic study, the tracheal mites were identified as Ptilonyssus morofskyi. Cleaning and disinfection of cages and perches, ivermectin application on the cervical skin of individual birds, enrofloxacin medication, and drinking water acidification with vinegar were used to control mortality. To the best of our knowledge, this is the first report of the occurrence of Ptilonyssus species in captive passerine birds.

An outbreak of thyroid hyperplasia (goiter) with high mortality in budgerigars (Melopsittacus undulatus).

An outbreak of goiter with high morbidity and mortality in a flock of budgerigars (Melopsittacus undulatus) in California is described. Forty-five out of 400 adult birds exhibited signs of illness, weight loss, and enlargement in the crop area; 15 of the 45 birds died over a 2-3-month period. Diet consisted of a commercial mixture with the addition of broccoli, whole oats, and carrots, but no minerals or supplements. Six budgerigars were subjected to necropsy; all 6 birds had severely enlarged thyroid glands. Thyroid follicular hyperplasia was histologically observed in all birds examined, while granulomatous thyroiditis and microfollicular adenoma were observed in 2 birds, respectively. Virological, bacteriological, parasitological, and heavy metal analyses were negative or within normal limits. The total iodine in the thyroid glands of affected birds was measured by inductively coupled plasma-mass spectrometry. Following iodine supplementation and removal of broccoli from the diet, the owner reported weight gain and a reduced death rate among clinically affected birds; no additional birds became sick. The presence of broccoli with its iodine-binding ability and the complete lack of added minerals in the diet of these animals were thought to be the predisposing factors for the outbreak in the present study. Outbreaks of goiter accompanied by high mortality are rare in any species and, to the best of the authors' knowledge, have not been described previously in any avian species. Recognition of this condition may help improve medical, welfare, and trade standards concerning this species.

Review of 23 cases of postintubation tracheal obstructions in birds.

Although recognized as a potential complication after endotracheal intubation in birds, the complication rate of postintubation tracheal obstruction in this taxon is unknown. Twenty-three cases of postintubation obstruction in birds from two institutions are reported. Clinical signs were noted an average of 16.6 days postintubation and consisted primarily of indications of acute respiratory distress. Diagnosis was confirmed via tracheoscopy or radiology. Five birds died before treatment could be initiated. Medical treatment alone was successful in three birds that had mild changes consisting primarily of a luminal mucoid plug that could be manually removed without tracheal surgery but was unsuccessful in an additional six birds. Tracheal resection and anastamosis was successful in four birds and unsuccessful in five birds. Overall mortality was 70%. Postintubation tracheal obstruction in birds appears to be more common in zoo practice than is suggested by the literature, as a total of 1.8% (1.2-2.7%, 95% confidence interval) of intubations or 3.5% (2.3-5.3%, 95% confidence interval) of individual animals intubated in these institutions resulted in this complication. Multiple cases were found in Ciconiiformes (n = 4), Columbiformes (n = 4), Gruiformes (n = 4), Anseriformes (n = 3), Galliformes (n = 3), and Passeriformes (n = 2). No cases were found in Coraciiforms, Falconiforms, or Psittaciformes despite many (>40) recorded intubations. The specific cause of these lesions is unclear, but some type of tracheal mucosa trauma or irritation is suggested by histologic findings. Prevention may include selective intubation, use of a laryngeal mask airway in place of intubation, careful placement of an endotracheal tube, minimal movement of the head and neck after placement, humidification of anesthetic gases, and gentle positive-pressure ventilation.

Serosurvey for selected infectious agents in two sympatric species of cormorants (Phalacrocorax atriceps and Phalacrocorax magellanicus) from coastal Patagonia, Argentina.

We conducted a serologic survey for selected infectious agents on two sympatric cormorants, the Imperial Cormorant (Phalacrocorax atriceps) and the Rock Shag (Phalacrocorax magellanicus). Blood was collected from 267 Imperial Cormorants and 106 Rock Shags at 17 colonies along the Patagonia Atlantic shore during nine breeding seasons (1994, 1999-2001-2005-2008-2010). Antibodies to four pathogens were common to both species and frequently observed: avian paramyxovirus type 1 (56% of Imperial Cormorants and 56% of Rock Shags); avian adenovirus (67% of Imperial Cormorants and 40% of Rock Shags); infectious bronchitis virus serotypes IBV-41, IBV-46, IBV-99, and IBV-JMK (53% of Imperial Cormorants and 64% of Rock Shags); and Salmonella pullorum (18% of Imperial Cormorants and 7% of Rock Shags). Antibody prevalence for these pathogens varied significantly between species, except for avian paramyxovirus type 1. Exposure to avian paramyxovirus type 1 and all serotypes of infectious bronchitis virus varied significantly among seasons in both species. In contrast, the sporadic occurrence of positive titers suggest that cormorants had occasional exposure to Aspergillus spp. (3% of Rock Shags, only in 2000), avian paramyxovirus type 3 (5% of Rock Shags, only in 2008), Chlamydophila spp. (1% of Imperial Cormorants, only in 2010), and avian reovirus (1% of Rock Shags, only in 1999; 29% of Imperial Cormorants, in 2008 and 2010). Both species were antibody negative for avian encephalomyelitis virus, avian influenza virus, avian laryngotracheitis virus, avian paramyxovirus type 2, and infectious bursal disease virus. We provide the first information on pathogen exposure, indicated by detection of antibody in blood samples, for two sympatric species of South Atlantic cormorants. To determine major causes of morbidity and mortality in these birds future efforts should focus on necropsy surveys in cormorant colonies.

The effect of exogenous corticosterone on West Nile virus infection in Northern Cardinals (Cardinalis cardinalis).

The relationship between stress and disease is thought to be unambiguous: chronic stress induces immunosuppression, which likely increases the risk of infection. However, this link has not been firmly established in wild animals, particularly whether stress hormones affect host responses to zoonotic pathogens, which can be transmitted to domesticated animal, wildlife and human populations. Due to the dynamic effects of stress hormones on immune functions, stress hormones may make hosts better or poorer amplifying hosts for a pathogen contingent on context and the host species evaluated. Using an important zoonotic pathogen, West Nile virus (WNV) and a competent host, the Northern Cardinal (Cardinalis cardinalis), we tested the effects of exogenous corticosterone on response to WNV infection. Corticosterone was administered at levels that individuals enduring chronic stressors (i.e., long-term inclement weather, food shortage, anthropogenic pollution) might experience in the wild. Corticosterone greatly impacted mortality: half of the corticosterone-implanted cardinals died between five - 11 days post-inoculation whereas only one of nine empty-implanted (control) birds died. No differences were found in viral titer between corticosterone- and empty-implanted birds. However, cardinals that survived infections had significantly higher average body temperatures during peak infection than individuals that died. In sum, this study indicates that elevated corticosterone could affect the survival of WNV-infected wild birds, suggesting that populations may be disproportionately at-risk to disease in stressful environments.

A novel herpesvirus in 3 species of pheasants: mountain peacock pheasant (Polyplectron inopinatum), Malayan peacock pheasant (Polyplectron malacense), and Congo peafowl (Afropavo congensis).

The mountain peacock pheasant (Polyplectron inopinatum), the Malayan peacock pheasant (Polyplectron malacense), and the Congo peafowl (Afropavo congensis) are all listed as vulnerable to extinction under the International Union for Conservation of Nature Red List of Threatened Species. Here the authors report fatal infection with a novel herpesvirus in all 3 species of birds. DNA was extracted from the livers of birds with hepatocellular necrosis and intranuclear eosinophilic inclusions consistent with herpesvirus infection. Based on degenerate herpesvirus primers and polymerase chain reaction, 220- and 519-base pair products of the herpes DNA polymerase and DNA terminase genes, respectively, were amplified. Sequence analysis revealed that all birds were likely infected with the same virus. At the nucleotide level, the pheasant herpesvirus had 92% identity with gallid herpesvirus 3 and 77.7% identity with gallid herpesvirus 2. At the amino acid level, the herpes virus had 93.8% identity with gallid herpesvirus 3 and 89.4% identity with gallid herpesvirus 2. These findings indicate that the closest relative to this novel herpesvirus is gallid herpesvirus 3, a nonpathogenic virus used widely in a vaccine against Marek's disease. In situ hybridization using probes specific to the peacock pheasant herpesvirus DNA polymerase revealed strong intranuclear staining in the necrotic liver lesions of an infected Malayan peacock pheasant but no staining in normal liver from an uninfected bird. The phasianid herpesvirus reported here is a novel member of the genus Mardivirus of the subfamily Alphaherpesvirinae and is distinct from other galliform herpesviruses.

Mortality factors and diseases in free-ranging Eurasian cranes (Grus grus) in Germany.

Detailed postmortem examinations were performed on 167 free-ranging Eurasian Cranes (Grus grus) from Germany, collected between September 1998 and December 2008 to evaluate causes of death and diseases. The most common causes of mortality were traumatic injuries (n=105, 62.9%) from collisions with power lines (n=39, 23.4%) and wire fences (n=12, 7.2%). A group of 28 Eurasian Cranes (16.8%) died from organophosphate intoxication. Predation by White-tailed Sea Eagles (Haliaeetus albicilla) and red foxes (Vulpes vulpes) occurred in four cases (2.4%). Pathologic changes due to infectious diseases were associated with Aspergillus spp. (n=7, 4.2%), endoparasites (n=7, 4.2%), avian poxvirus (n=6, 3.6%), Mycobacterium spp. (n=2, 1.2%), and adenovirus infection (n=1, 0.6%). A severe Strigea spp. infection (n=1, 0.6%) and a leiomyosarcoma (n=1, 0.6%) were newly recognized diseases in Eurasian Cranes in this study.

A retrospective study of post-mortem examination findings in takahe (Porphyrio hochstetteri).

AIMS: To identify the major diseases or disease processes affecting both captive and wild populations of takahe (Porphyrio hochstetteri) in birds submitted for post-mortem examination between 1992 and 2007, and to survey archived wild dead takahe for the presence of Erysipelothrix rhusiopathiae. METHODS: Reports of 199 post-mortem examinations submitted between 1992 and 2007 were reviewed retrospectively. The reports comprised 56 eggs, 51 chicks up to 6 months of age, 13 sub-adults 6-18 months old, 74 adults and five birds where age was not recorded. Bone marrow flushed from the keel of 34 frozen adult takahe was assayed for the presence of E. rhusiopathiae, using PCR analysis. RESULTS: Of the eggs examined, 6/56 (11%) had no recorded diagnosis, 24/56 (43%) were infertile and 26/56 (46%) showed embryonic mortality at various stages. Excluding eggs, the cause of death could not be determined in 64/138 (46%) birds with a recorded age that were examined. Contributing factors for the low rate of diagnosis included advanced decomposition of many carcasses, the freezing of some birds prior to pathological investigation, long delays between recovery and submission for post-mortem examination, and variation in the extent of post-mortem examination and ancillary diagnostic testing. Common post-mortem examination findings in chicks included those related to cardiac disease [11/51 (22%)], infectious or inflammatory disease [9/51 (18%)] and trauma [7/51 (14%)]. In adult birds, the most common post-mortem examination findings were due to infectious or inflammatory disease [15/74 (20%)] including septicaemia due to E. rhusiopathiae [3/74 (7%)], followed by degenerative conditions due to diet, age and husbandry [9/74 (12%)]. Bacteria implicated in the causes of death included Escherichia coli, E. rhusiopathiae, Salmonella enterica serovar Typhimurium, and Pseudomonas aeruginosa. Only 1/34 (3%) of the frozen carcass examined using PCR was positive for E. rhusiopathiae. CONCLUSIONS: This study highlights a need for improved recovery, storage and submission of dead takahe for pathological examination; consistency in post-mortem examination, ancillary testing and recording of findings; and finally, regular communication between wildlife pathologists, conservation workers and representatives of Ngai Tahu.

Survival of radio-marked mallards in relation to management of avian botulism.

Avian botulism outbreaks are frequently perpetuated by type C toxin produced by Clostridium botulinum proliferating in decomposing bird carcasses and consumption of toxic maggots from these carcasses by healthy birds. Therefore, removing bird carcasses has been advocated for disease management because availability of toxic maggots should be reduced, increasing duck survival. However, this management is expensive, and its effect on waterfowl mortality under field conditions is unknown. We radio-marked 419 molting mallards on 11 lakes in western Canada during July-August 1999-2001 and monitored them for 30 days, testing whether survival was higher on lakes with carcass removal. Botulism occurred on 10 lakes. On five carcass removal lakes, greater-than-normal effort was made to conduct early, thorough surveillance and immediately remove carcasses; on six nonremoval lakes, no carcasses were removed. In 1999, estimated 30-day survival probabilities ranged from 0.149 (95% CI=0.065-0.304) on one large lake with carcass removal to 0.466 (95% CI=0.270-0.674) and 0.618 (95% CI=0.443-0.767) on two nonremoval lakes. As a result, we conducted work on smaller wetlands thereafter, reasoning that any management benefit would be easier to detect. In 2000, estimated 30-day survival probabilities were 0.313 (95% CI=0.143-0.556) and 0.794 (95% CI=0.609-0.905) on two carcass removal lakes versus 0.525 (95% CI=0.362-0.682) and 0.743 (95% CI=0.564-0.866) on two nonremoval lakes. In 2001, botulism was detected on two nonremoval lakes where survival probabilities were 0.845 (95% CI=0.630-0.946) and 0.942 (95% CI=0.778-0.987), and on one removal lake where survival probability was 1.0 (95% CI=0.99-1.0), but not detected on the other removal lake where no marked birds died from botulism (1.0, 95% CI=0.99-1.0). Survival tended to be higher on lakes with lower carcass density, but when data were organized by carcass removal versus nonremoval, mallard survival was not consistently greater on lakes where carcasses were removed.