Avian keratin disorder of Alaska black-capped chickadees is associated with Poecivirus infection.

BACKGROUND: Avian keratin disorder (AKD) is an epizootic of debilitating beak deformities, first documented in black-capped chickadees (Poecile atricapillus) in Alaska during the late 1990s. Similar deformities have now been recorded in dozens of species of birds across multiple continents. Despite this, the etiology of AKD has remained elusive, making it difficult to assess the impacts of this disease on wild populations. We previously identified an association between infection with a novel picornavirus, Poecivirus, and AKD in a small cohort of black-capped chickadees. METHODS: To test if the association between Poecivirus and AKD holds in a larger study population, we used targeted PCR followed by Sanger sequencing to screen 124 symptomatic and asymptomatic black-capped chickadees for Poecivirus infection. We further compared the efficacy of multiple non-terminal field sampling methods (buccal swabs, cloacal swabs, fecal samples, and blood samples) for Poecivirus screening. Finally, we used both in situ hybridization and a strand-specific expression assay to localize Poecivirus to beak tissue of AKD-positive individuals and to determine if virus is actively replicating in beak tissue. RESULTS: Poecivirus was detected in 28/28 (100%) individuals with AKD, but only 9/96 (9.4%) asymptomatic individuals with apparently normal beaks (p < 0.0001). We found that cloacal swabs are the most sensitive of these sample types for detecting Poecivirus in birds with AKD, but that buccal swabs should be combined with cloacal swabs in evaluating the infection status of asymptomatic birds. Finally, we used both in situ hybridization and a strand-specific expression assay to localize Poecivirus to beak tissue of AKD-positive individuals and to provide evidence of active viral replication. CONCLUSION: The data presented here show a strong, statistically significant relationship between Poecivirus infection and AKD, and provide evidence that Poecivirus is indeed an avian virus, infecting and actively replicating in beak tissue of AKD-affected BCCH. Taken together, these data corroborate and extend the evidence for a potential causal association between Poecivirus and AKD in the black-capped chickadee. Poecivirus continues to warrant further investigation as a candidate agent of AKD.

Pathogenicity of a variant goose parvovirus, from short beak and dwarfism syndrome of Pekin ducks, in goose embryos and goslings.

The pathogenicity of a variant goose parvovirus (GPV), isolated from short beak and dwarfism syndrome of Pekin ducks (strain Cherry Valley), was investigated in embryonating goose eggs and goslings. The virus was easily grown in GPV antibody-free goose embryos and caused high mortality and severe lesions of goose embryos, indicating that the variant GPV has good adaptation and high pathogenicity to embryonated goose eggs similar to the classical GPV. Like the third egg-passage virus (strain H) of a classical GPV, the third egg-passage virus (strain JS1) of the variant GPV caused Derzsy's disease in 2-day-old goslings with high mortality. The findings suggest that the variant GPV strain, which had specifically adapted to Pekin ducks, still retained high pathogenicity for its original host. The mortality (73.3-80%) caused by the first and third egg-passages of the variant GPV was somewhat lower than that (93.3%) caused by the third passage virus of the classical GPV, reflecting the higher pathogenicity of the classical GPV for its original host. These findings are likely to reinforce the importance of surveillance for parvoviruses in different waterfowl species and stimulate further study to elucidate the impact of mutations in the GPV genome on its pathogenicity to goslings and ducks.

Identification of Goose-Origin Parvovirus as a Cause of Newly Emerging Beak Atrophy and Dwarfism Syndrome in Ducklings.

A recent epizootic outbreak, in China, of duck beak atrophy and dwarfism syndrome (BADS) was investigated using electron microscopic, genetic, and virological studies, which identified a parvovirus with a greater similarity to goose parvovirus (GPV) (97% protein homology) than to Muscovy duck parvovirus (MDPV) (90% protein homology). The new virus, provisionally designated GPV-QH15, was found to be antigenically more closely related to GPV than to MDPV in a virus neutralization assay. These findings were further supported by phylogenetic analysis showing that GPV-QH15 evolved from goose lineage parvoviruses, rather than from Muscovy duck- or other duck species-related parvoviruses. In all, two genetic lineages (GPV I and GPV II) were identified from the GPV samples analyzed, and GPV-QH15 was found to be closely clustered with two known goose-origin parvoviruses (GPVa2006 and GPV1995), together forming a distinctive GPV IIa sublineage. Finally, structural modeling revealed that GPV-QH15 and the closely related viruses GPVa2006 and GPV1995 possessed identical clusters of receptor-interacting amino acid residues in the VP2 protein, a major determinant of viral receptor binding and host specificity. Significantly, these three viruses differed from MDPVs and other GPVs at these positions. Taken together, these results suggest that GPV-QH15 represents a new variant of goose-origin parvovirus that currently circulates in ducklings and causes BADS, a syndrome reported previously in Europe. This new finding highlights the need for future surveillance of GPV-QH15 in poultry in order to gain a better understanding of both the evolution and the biology of this emerging parvovirus.

Isolation and characterization of a distinct duck-origin goose parvovirus causing an outbreak of duckling short beak and dwarfism syndrome in China.

Many mule duck and Cherry Valley duck flocks in different duck-producing regions of China have shown signs of an apparently new disease designated "short beak and dwarfism syndrome" (SBDS) since 2015. The disease is characterized by dyspraxia, weight loss, a protruding tongue, and high morbidity and low mortality rates. In order to characterize the etiological agent, a virus designated SBDSV M15 was isolated from allantoic fluid of dead embryos following serial passage in duck embryos. This virus causes a cytopathic effect in duck embryo fibroblast (DEF) cells. Using monoclonal antibody diagnostic assays, the SBDSV M15 isolate was positive for the antigen of goose parvovirus but not Muscovy duck parvovirus. A 348-bp (2604-2951) VP1gene fragment was amplified, and its sequence indicated that the virus was most closely related to a Hungarian GPV strain that was also isolated from mule ducks with SBDS disease. A similar disease was reproduced by inoculating birds with SBDSV M15. Together, these data indicate that SBDSV M15 is a GPV-related parvovirus causing SBDS disease and that it is divergent from classical GPV isolates.

External Beam Radiation Therapy of Squamous Cell Carcinoma in the Beak of an African Grey Parrot (Psittacus timneh).

Squamous cell carcinoma has been reported in a variety of bird species, most commonly psittacine and gallinaceous birds. The long-term prognosis in nongallinaceous birds is generally poor if complete surgical excision is not possible. Squamous cell carcinoma of the rhinotheca was diagnosed in a 34-year-old timneh African grey parrot (Psittacus timneh) with a 2-year history of beak abnormalities. No evidence of metastasis or local invasion were found on results of radiographs or computed tomography scan. The bird was treated with surgical debulking and palliative megavoltage radiation therapy. After 4 radiation treatments, the affected tissue was necrotic and was debrided to reveal healthy granulation tissue. The bird died approximately 7 months after diagnosis and 4 months after cessation of radiation treatment. At the time of death, a small scab lesion remained at the left oral commissure, but no visible tumor regrowth was evident. A postmortem examination was not performed, however, and tumor recurrence could not be ruled out in this bird.

Molecular analysis and associated pathology of beak and feather disease virus isolated in Italy from young Congo African grey parrots (Psittacus erithacus) with an "atypical peracute form" of the disease.

This study is the first report on the genetic and pathogenic characterization of beak and feather disease virus (BFDV) occurring in Italy. Twenty BFDV strains isolated in Italy from juvenile Congo African grey parrots (Psittacus erithacus) were investigated. Seventeen strains showed an "atypical peracute form" (aPF) of the disease, and three a chronic form (CF). The birds with aPF had been weaned, were independent as far as food and protection were concerned and apparently were without lesions. The gene coding for the putative coat protein was amplified in all isolates while the BFDV genome was sequenced completely in 10 samples, eight of them belonging to aPF affected birds and two from CF of the disease. All full genomes clustered into the J strain of BFDV, where two new subtypes were identified. Recombination analyses showed evidence of genetic exchanges in two BFDV genomes. In addition, a correlation between viral isolate and origin of the breeding material was shown, while an association between the genetic features of the virus and the clinical form was not observed. Histologically, apoptosis was detected frequently in aPF samples and sporadically in CF samples. Interestingly, BFDV antigens were detected in the nuclei and cytoplasm of such apoptotic cells. The data presented here support the hypothesis that, in the absence of a defined BFDV genetic variant accountable for a specific clinical form of psittacine beak and feather disease, differences in the apoptotic rate between aPF and CF are strictly host related.

Macroscopic, histologic, and ultrastructural lesions associated with avian keratin disorder in black-capped chickadees (Poecile atricapillus).

An epizootic of beak abnormalities (avian keratin disorder) was recently detected among wild birds in Alaska. Here we describe the gross, histologic, and ultrastructural features of the disease in 30 affected adult black-capped chickadees (Poecile atricapillus). Grossly, there was elongation of the rhamphotheca, with varying degrees of lateral deviation, crossing, and gapping between the upper and lower beak. Not uncommonly, the claws were overgrown, and there was alopecia, scaling, and crusting of the skin. The most prominent histopathologic features in the beak included epidermal hyperplasia, hyperkeratosis, and core-like intrusions of necrotic debris. In affected birds, particularly those with moderate to severe beak overgrowth, there was remodeling of premaxillary and mandibular bones and various dermal lesions. Lesions analogous to those found in beaks were present in affected claws, indicating that this disorder may target both of these similar tissues. Mild to moderate hyperkeratosis occurred in other keratinized tissues, including skin, feather follicles, and, occasionally, sinus epithelium, but typically only in the presence of microbes. We did not find consistent evidence of a bacterial, fungal, or viral etiology for the beak lesions. The changes observed in affected birds did not correspond with any known avian diseases, suggesting a potentially novel hyperkeratotic disorder in wild birds.

Mycobacterium marinum infection in a blue-fronted Amazon parrot (Amazona aestiva).

A blue-fronted Amazon parrot (Amazona aestiva) was presented with a granuloma involving the proximal rhinotheca and extending into the rostral sinuses. Mycobacterium marinum was diagnosed based on results of biopsy and culture. Treatment was initiated with clarithromycin, rifampin, and ethambutol, but the bird died 4 months after the onset of antimicrobial therapy. Additional granulomas were found in the left lung and liver on postmortem examination. Mycobacterial isolation on postmortem samples was unsuccessful. This is the first report of Mycobacterium marinum in a bird.

Reproduction and pathogenesis of short beak and dwarfish syndrome in Cherry Valley Pekin ducks infected with the rescued novel goose parvovirus.

Since the outbreak of short beak and dwarfish syndrome (SBDS) in Cherry Valley Pekin ducks in China, novel goose parvovirus (NGPV) has been isolated. Till now, little is known about the NGPV pathogenesis toward Cherry Valley Pekin ducks. Besides, due to detection of duck circovirus co-infection in SBDS clinical cases, whether sole NGPV infection can reproduce all the typical symptoms of SBDS remains unclear. In this study, based on the NGPV isolate SDJN19, an infectious plasmid clone pJNm containing the entire SDJN19 genome was constructed. Transfection of pJNm in embryonated duck eggs resulted in generation of the infectious virus carrying the genetic marker, named rJNm. rJNm infection of 2-day-old Cherry Valley Pekin ducks reproduced all the typical signs of SBDS, including beak atrophy, tongue protrusion, and growth retardation. rJNm can infect Cherry Valley Pekin ducks through the horizontal transmission route, and the infected ducks exhibited the characteristic SBDS symptoms. A high level of serum precipitation antibodies (above 5log2) were induced in the surviving ducks, however, high viral loads were still detected in the duck organs, suggesting persistent NGPV infection in ducks. By incorporating the homologous Rep1 and VP1 gene from classical GPV, two chimeric viruses rJN-cVP1 and rJN-cRep1 were generated. Duck infection tests revealed that the non-structural protein Rep1 played a crucial role in the NGPV pathogenicity. The present result lays a solid foundation for further exploring how the Rep protein contributes to the NGPV pathogenesis.

Molecular Identification and Pathogenicity of Novel Duck-Origin Goose Parvovirus Isolated from Beak Atrophy and Dwarfism Syndrome of Waterfowls in the North of Vietnam.

The aim of this study is to identify and characterize virus isolates (which are named for Bacgiang Agriculture and Forestry University [BAFU]) from diseased Cherry Valley duck and mule duck flocks and investigate the damage caused by a novel parvovirus-related virus (DuPV) to tissues and organs, including the brain, cerebellum, kidney, liver, lung, spleen, and spinal cord. The results of phylogenetic analysis show that DuPV-BAFU evolved from a goose lineage and duck parvoviruses rather than from Muscovy duck parvoviruses. In the genetic lineages, DuPVs were identified from the DuPV samples analyzed, and DuPV-BAFU was found to be closely clustered with two known goose origin parvoviruses (GPVa2006 and GPV1995) and a duck GPVs. Finally, structural modeling revealed that DuPV-BAFU and the closely related viruses GPVa2006 and GPV1995 possessed identical clusters of receptor-interacting amino acid residues in the VP3 protein, a major determinant of viral receptor binding and host specificity. Significantly, these three viruses differed from DuPVs, Muscovy duck parvoviruses, and other goose parvoviruses at these positions. These results also demonstrated that DuPV-BAFU represents a new variant of goose-origin parvovirus that currently circulates in ducklings and causes beak atrophy and dwarfism syndrome, as noted in the previous reports in Europe, Taiwan, and China. This new finding highlights the need for future surveillance of DuPV-BAFU in waterfowl in order to gain a better understanding of both the evolution and the biology of this emerging parvovirus in waterfowl.

Identificación molecular y patogenicidad de un nuevo parvovirus de ganso de origen en pato aislado del síndrome de atrofia del pico y enanismo de las aves acuáticas en el norte de Vietnam. El objetivo de este estudio es identificar y caracterizar aislados de virus detectados en la Universidad de Agricultura y Silvicultura de Bacgiang (BAFU) de parvadas de patos enfermos Cherry Valley e híbridos y también investigar el daño causado por un nuevo virus relacionado con parvovirus del pato (DuPV) en tejidos y órganos, incluidos el cerebro, el cerebelo, los riñones, el hígado, los pulmones, el bazo y la médula espinal. Los resultados del análisis filogenético mostraron que el virus DuPV-BAFU evolucionó a partir de un linaje de parvovirus de patos y gansos en lugar del parvovirus de patos reales. En los linajes genéticos, se identificaron virus DuPV a partir de las muestras de DuPV analizadas, y se encontró que el DuPV-BAFU estaba estrechamente agrupado con dos parvovirus conocidos de origen de ganso (GPVa2006 y GPV1995) y con parvovirus de pato. Finalmente, el modelado estructural reveló que el virus DuPV-BAFU y los virus estrechamente relacionados GPVa2006 y GPV1995 poseían grupos idénticos de residuos de aminoácidos que interactúan con el receptor en la proteína VP3, que es un determinante importante de la unión al receptor viral y la especificidad del huésped. Significativamente, estos tres virus diferían de los DuPV, los parvovirus del pato real y de otros parvovirus del ganso en estas posiciones. Estos resultados también demostraron que el virus DuPV-BAFU representa una nueva variante del parvovirus de origen ganso que actualmente circula en patitos y causa atrofia del pico y síndrome de enanismo, como se señaló en reportes anteriores en Europa, Taiwán y China. Este nuevo hallazgo destaca la necesidad de una vigilancia futura para el virus DuPV-BAFU en las aves acuáticas para comprender mejor tanto la evolución como la biología de este parvovirus emergente en las aves acuáticas.

Outbreaks of Avipoxvirus Clade E in Vaccinated Broiler Breeders with Exacerbated Beak Injuries and Sex Differences in Severity.

Avipoxvirus affects chickens and wild birds, and it is characterized by lesions on the nonfeathered parts of the body (the cutaneous form), or necrotic lesions in the upper respiratory tract (the diphtheritic form). In poultry farming, avian pox is usually controlled by live attenuated vaccines. However, there have been many reports of outbreaks, even in flocks of vaccinated birds. In the present study, different outbreaks of the emerging clade E avipoxvirus were detected in commercial breeder flocks of chickens vaccinated against fowlpox virus in Southeast Brazil. Clinical manifestations of these outbreaks included a marked prevalence of moderate to severe progressive lesions in the beaks of affected birds, especially in roosters with increased mortality (up to 8.48%). Also, a reduced hatchability (up to 20.77% fewer hatching eggs) was observed in these flocks. Analysis of clinical samples through light and transmission electron microscopy revealed the presence of Bollinger bodies and poxvirus particles in epithelial cells and affecting chondrocytes. PCR, sequencing, and phylogenetic analysis of major core protein (P4b) and DNA polymerase (pol) genes identified this virus as clade E avipoxvirus. We also developed qPCR assays for open reading frames (ORFs) 49, 114, and 159 to detect and quantify this emergent virus. These results show the arrival and initial spread of this pathogen in the poultry industry, which was associated with harmful outbreaks and exacerbated clinical manifestations in vaccinated commercial breeder flocks. This study also highlights the relevance of permanent vigilance and the need to improve sanitary and vaccination programs.

Necrotic dermatitis in waterfowl associated with consumption of perennial rye grass (Lolium perenne).

Mute swans (Cygnus olor), whooper swans (Cygnus cygnus), and mixed-breed domestic geese (Anser anser domesticus) were presented for necrotic lesions on the feet, eyelids, and beak. Individuals from the same collection of birds had developed identical lesions during March-September of each of the previous 3 years. Vesicular and necrotic dermatitis involved only nonfeathered and nonpigmented areas of the integument. No abnormal clinical signs were seen on either carnivorous species or birds with pigmented skin from the same collection. The enclosure that housed the birds had been planted with perennial rye grass (Lolium perenne) 3 years previously. Based on the pathologic features and anatomic location of the lesions, the seasonal occurrence, the vegetation history of the enclosure, and the feeding behavior of the affected species, vesicular dermatitis resulting from photosensitization was the presumptive diagnosis. All affected birds recovered completely after the birds were removed from the enclosure, and no further clinical signs have been reported.

POECIVIRUS IS PRESENT IN INDIVIDUALS WITH BEAK DEFORMITIES IN SEVEN SPECIES OF NORTH AMERICAN BIRDS.

Avian keratin disorder (AKD), a disease of unknown etiology characterized by debilitating beak overgrowth, has increasingly affected wild bird populations since the 1990s. A novel picornavirus, poecivirus, is closely correlated with disease status in Black-capped Chickadees (Poecile atricapillus) in Alaska, US. However, our knowledge of the relationship between poecivirus and beak deformities in other species and other geographic areas remains limited. The growing geographic scope and number of species affected by AKD-like beak deformities require a better understanding of the causative agent to evaluate the population-level impacts of this epizootic. Here, we tested eight individuals from six avian species with AKD-consistent deformities for the presence of poecivirus: Mew Gull (Larus canus), Hairy Woodpecker (Picoides villosus), Black-billed Magpie (Pica hudsonia), American Crow (Corvus brachyrhynchos), Red-breasted Nuthatch (Sitta canadensis), and Blackpoll Warbler (Setophaga striata). The birds were sampled in Alaska and Maine (1999-2016). We used targeted PCR followed by Sanger sequencing to test for the presence of poecivirus in each specimen and to obtain viral genome sequence from virus-positive host individuals. We detected poecivirus in all individuals tested, but not in negative controls (water and tissue samples). Furthermore, we used unbiased metagenomic sequencing to test for the presence of other pathogens in six of these specimens (Hairy Woodpecker, two American Crows, two Red-breasted Nuthatches, Blackpoll Warbler). This analysis yielded additional viral sequences from several specimens, including the complete coding region of poecivirus from one Red-breasted Nuthatch, which we confirmed via targeted PCR followed by Sanger sequencing. This study demonstrates that poecivirus is present in individuals with AKD-consistent deformities from six avian species other than Black-capped Chickadee. While further investigation will be required to explore whether there exists a causal link between this virus and AKD, this study demonstrates that poecivirus is not geographically restricted to Alaska, but rather occurs elsewhere in North America.

Beak necrosis in Hungarian partridges (Perdix perdix) associated with beak-bits and avian poxvirus infection.

Proliferative growth, consistent with poxvirus infection, encapsulated plastic beak-bits and covered the dorsal portion of the upper beak and nares of adult male and female captive-raised Hungarian partridges. Three representative birds were submitted to the Wisconsin Veterinary Diagnostic Laboratory for necropsy. Lesions in the necropsied birds extended through the nares, where the plastic bit ends are designed to rest. The lesions also variably extended caudally into the oropharynx and cranially within the beak epithelium, and included palate deformity and beak necrosis. Poxvirus was diagnosed in all of the birds examined based on histopathology, electron microscopy, and polymerase chain reaction amplification and sequencing. This report is the first to describe avian pox lesions associated with the application of beak-bits and the resulting beak and oral pathology.

Metastatic melanoma appearing to originate from the beak of a racing pigeon (Columba livia).

A 12-year-old male pigeon (Columba livia) was reported to have a small lesion on the lower beak, which was diagnosed as malignant melanoma. After surgery to remove it, the general condition of the bird worsened and the bird died. Post mortem examination revealed gross, black-colored lesions in the liver, kidney, spleen, and femur bone marrow. Lesions were not found in the adrenals. Histopathologically, the neoplastic cells had a large amount of melanin pigment and showed severe anisokaryosis and prominent nucleoli. Mitotic activity was infrequent but varied considerably where it was observed.

Identification and Characterization of a Distinct Strain of Beak and Feather Disease Virus in Southeast China.

Beak and feather disease virus (BFDV) is an infectious agent responsible for feather degeneration and beak deformation in birds. In March 2017, an epidemic of psittacine beak and feather disease (PBFD) struck a farm in Fuzhou in the Fujian Province of southeast China, resulting in the death of 51 parrots. In this study, the disease was diagnosed and the pathogen was identified by PCR and whole genome sequencing. A distinct BFDV strain was identified and named as the FZ strain. This BFDV strain caused severe disease symptoms and pathological changes characteristic of typical PBFD in parrots, for example, loss of feathers and deformities of the beak and claws, and severe pathological changes in multiple organs of the infected birds. Phylogenetic analysis showed that the FZ strain was more closely related to the strain circulating in New Caledonia than the strains previously reported in China. Nucleotide homology between the FZ strain and other 43 strains of BFDV ranged from 80.0% to 92.0%. Blind passage experiment showed that this strain had limited replication capability in SPF Chicken Embryos and DF-1 Cells. Furthermore, the capsid (Cap) gene of this FZ strain was cloned into the pGEX-4T-1 expression vector to prepare the polyclonal anti-Cap antibody. Western blotting analysis using the anti-Cap antibody further confirmed that the diseased parrots were infected with BFDV. In this study, a PBFD and its pathogen was identified for the first time in Fujian Province of China, suggesting that future surveillance of BFDV should be performed.

Soft tissue sarcoma in a short-beaked echidna (Tachyglossus aculeatus).

CASE REPORT: An adult male short-beaked echidna in poor body condition was found with a 25 × 12 mm round, ulcerated and bleeding mass on the left side of the face at the base of the beak. The animal responded well to initial supportive care and was referred to a specialist wildlife centre for further assessment and treatment. Clinical pathology showed moderate neutrophilia, mild anaemia, mild elevation in liver enzymes (ALT, AST and ALP) and mild azotaemia. Initial clinical differential diagnoses for the facial mass favoured an inflammatory rather than a neoplastic lesion, based on previous reports. Examination of an incisional biopsy identified a malignant spindle cell proliferation (sarcoma) not amenable to complete surgical excision. The animal was euthanased on humane grounds. Immunohistochemical assessment of the mass showed it to be negative for cytokeratin, desmin, smooth muscle actin, periaxin and MAC387 antibody labelling. Definitive histogenesis was undetermined and a final diagnosis of poorly differentiated sarcoma, unlikely to be of muscle, Schwann cell or histiocytic origin, was made. CONCLUSION: Reports of neoplasia in prototherian mammals (monotremes) are rare. To the authors' knowledge this is the first report of such a tumour in a monotreme species and the first immunohistochemical characterisation of a stromal tumour in these animals. The malignant nature of this tumour contrasts with a previous report of benign neoplasia (fibroma) associated with the beak. Although rare, malignant neoplasia should be included in the differential diagnoses of mass lesions in monotremes, despite inflammatory or traumatic mass lesions being more commonly reported.

Bill impaction in a group of captive Caribbean flamingos (Phoenicopterus ruber ruber).

Flamingos are filter feeders that only rarely ingest larger food items. Their bill anatomy is adapted to the suction, filtration, and ejection of a fluid medium. This case report documents a rare case of bill impaction in a group of Caribbean flamingos (Phoenicopterus ruber) that were kept in a mixed exhibit together with roseate spoonbills (Platalea ajaja) and scarlet ibis (Eudocimus ruber). The latter species received fatty minced meat as part of their diet, which was also accessible to the flamingos. Weakness and poor body condition of one flamingo were noted. On clinical examination, the animal was emaciated, hypoglycemic, and showed a severe impaction of the bill with a mixture of lard, mud, and sand. This mixture had compressed the tongue and eventually had most likely prevented further food intake. In five additional flamingos, a bulging of the gular area, similar to the extension of this area during the tongue-retraction stage of the feeding cycle, was noted and interpreted as a sign of tongue displacement by similar masses in their bills. All animals were caught and the masses removed. All animals resumed food intake immediately, and the emaciated animal rapidly improved in condition. Food presentation was changed so that the trays for the other species were no longer accessible to the flamingos, and no similar problems have been observed since that time.

Morphologically abnormal beaks observed in chickens that were beak-trimmed at young ages.

A survey of beak morphological abnormalities was performed on 6,201 chickens (egg-laying hens and chickens for meat production belonging to 25 flocks) brought to a poultry processing plant. The observed abnormalities varied among flocks with occurrence rates ranging from 0.48 to 46.67%. The occurrence was high in flocks subjected to beak trimming and varied significantly according to chicken breed, with the highest rates of abnormalities in a certain chicken breed. The most widely observed abnormalities were: 1) uneven growth of the upper and lower mandibles, mostly with elongation of the lower mandible (accounting for 64.8% of all abnormalities); 2) misalignment of the upper and lower mandibles, causing lateral deviation or crossing (16.3%); 3) sharp or jagged deformities of the mandible tips (10.1%); 4) permanent open beak, a deformity in which the beak did not close completely even when closed (5.8%); and 5) formation of tubercular swellings at the tips of the upper or lower mandibles (3.1%). This is the first report on the occurrence of beak abnormalities in beak-trimmed poultry in Japan.

Pathogenicity of Pekin duck- and goose-origin parvoviruses in Pekin ducklings.

Goose parvovirus (GPV) usually affects goslings and Muscovy ducks but not Pekin ducks. Earlier works showed that a variant GPV can cause short beak and dwarfism syndrome (SBDS) in Pekin ducks. Here, we investigated the pathogenicity of a variant GPV of Pekin duck-origin (JS1) and a classical GPV of goose-origin (H) in Pekin ducklings. Following intramuscular infection at two days of age, both JS1 and H strains influenced weight gain and development of beaks and bones of wings and legs, and caused microscopic lesions of internal organs of ducks. However, the clinical signs typical of SBDS could only be replicated with the JS1 isolate. The findings suggest that both variant and classical GPVs are pathogenic for Pekin ducklings, while the former is more virulent than the latter. Using a quantitative real-time PCR assay, high levels of viral load were detected from bloods, internal organs, leg muscles, and ileac contents in JS1- and H-infected ducks from 6h to 35days postinfection (DPI). Using a GPV VP3-based ELISA, antibodies in sera of JS1- and H-infected ducks were detectable at 1 DPI and then persistently rose during the subsequent five weeks. These results suggest that both variant and classical GPVs can infect Pekin ducklings. The present work contributes to the understanding of pathogenicity of GPV to Pekin ducks and may provide clues to pathogenesis of GPV-related SBDS.