Lipid storage disease in 4 sibling superb birds-of-paradise (Lophorina superba)

Pedigree analysis, clinical, gross, microscopic, ultrastructural, and lipidomic findings in 4 female superb bird-of-paradise (SBOP, Lophorina superba) siblings led to the diagnosis of a primary inherited glycerolipid storage disease. These birds were the offspring of a related breeding pair (inbreeding coefficient = 0.1797) and are the only known SBOPs to display this constellation of lesions. The birds ranged from 0.75 to 4.3 years of age at the time of death. Two birds were euthanized and 1 died naturally due to the disease, and 1 died of head trauma with no prior clinical signs. Macroscopic findings included hepatomegaly and pallor (4/4), cardiac and renal pallor (2/4), and coelomic effusion (1/4). Microscopic examination found marked tissue distortion due to cytoplasmic lipid vacuoles in hepatocytes (4/4), cardiomyocytes (4/4), renal tubular epithelial cells (4/4), parathyroid gland principal cells (2/2), exocrine pancreatic cells (3/3), and the glandular cells of the ventriculus and proventriculus (3/3). Ultrastructurally, the lipids were deposited in single to coalescing or fused droplets lined by an inconspicuous or discontinuous monolayer membrane. Lipidomic profiling found that the cytoplasmic lipid deposits were primarily composed of triacylglycerols. Future work, including sequencing of the SBOP genome and genotyping, will be required to definitively determine the underlying genetic mechanism of this disease.

T-cell Thymic Lymphoma With Proventricular Metastasis in a Florida Scrub Jay ( Aphelocoma coerulescens)

An adult, wild-caught, female Florida scrub jay ( Aphelocoma coerulescens) was evaluated because of an observable mass on the ventral neck. Initial physical examination and diagnostic tests were performed, which revealed a subcutaneous mass. Surgical removal of the mass was attempted, but the bird died during surgery. Results of necropsy and histopathologic evaluation identified the mass as thymic lymphoma with proventricular metastasis. Immunohistochemical staining revealed strong cytoplasmic immunoreactivity for CD3 in the thymic mass and within the predominant lymphoid population in the serosal proventricular masses, which confirmed metastasis of T-cell lymphoma. To our knowledge, this is the first report of T-cell thymic lymphoma in a wild Florida scrub jay.

Evaluation of gastroscopy and biopsy of the proventriculus and ventriculus in pigeons (Columba livia)

OBJECTIVE To evaluate the efficacy and safety of gastroscopy and biopsy of the proventriculus and ventriculus in pigeons (Columba livia). ANIMALS 15 adult pigeons. PROCEDURES Each pigeon was anesthetized, and the upper gastrointestinal tract (from the cervical portion of the esophagus to the ventriculus) was endoscopically evaluated by use of a rigid endoscope inserted orally. Saline (0.9% NaCl) solution was orally infused to achieve lumen dilation and visibility. Two mucosal biopsy specimens were collected from each of the proventriculus and ventriculus, histologically evaluated, and graded for crush artifacts and depth. Pigeons were monitored for adverse effects for 3 to 6 days after the procedure, after which they were euthanized for necropsy. RESULTS Gastroscopy via the oral approach provided excellent visibility of the lumen and mucosal surfaces of the proventriculus and cranial portion of the ventriculus and was safe provided that appropriate precautions were taken. Two intraoperative deaths occurred at the beginning of the study; following procedure refinement, no additional deaths occurred. No major adverse effects of the procedure were detected in the remaining 13 pigeons during the postoperative monitoring period or at necropsy. Diagnostic quality of proventriculus specimens was adequate for 10 of 13 pigeons. Eight of 13 ventriculus specimens were of inadequate quality, and only 3 were of adequate quality. CONCLUSIONS AND CLINICAL RELEVANCE Gastroscopy was useful for evaluating the lumen and mucosal surface of the proventriculus and ventriculus in pigeons, and biopsy of those organs was safely performed with the appropriate technique. Further evaluation of these techniques is needed in birds with clinical disease and birds of other species.

Avian bornavirus and proventricular dilatation disease: diagnostics, pathology, prevalence, and control

Avian bornavirus (ABV) has been shown the cause of proventricular dilatation disease (PDD) in psittacines. Many healthy birds are infected with ABV, and the development of PDD in such cases is unpredictable. As a result, the detection of ABV in a sick bird is not confirmation that it is suffering from PDD. Treatment studies are in their infancy. ABV is not restricted to psittacines. It has been found to cause PDD-like disease in canaries. It is also present at a high prevalence in North American geese, swans, and ducks. It is not believed that these waterfowl genotypes can cause disease in psittacines.

Newcastle disease in geese: natural occurrence and experimental infection

A novel disease entity in domestic geese with unusual epidemiology and pathological changes has emerged in some regions of China since the late 1990s. Velogenic Newcastle disease (ND) viruses were isolated from visceral organs and cloacal swabs of diseased birds in the field. Gross lesions of diseased geese were characterized by extensive necrotic foci in intestinal mucosa, spleen and pancreas. Histological examination revealed multisystemic distribution of lesions. Similar disease was reproduced experimentally in geese not only with two field isolates of goose origin, but also with ND viruses belonging to genotypes VI, VII, VIII and IX. These led us to define the novel disease as clinical ND in geese. Additionally, the goose-originated ND virus isolates could be transmitted from geese to specific pathogen free chickens, illustrating the potential threat they posed to the chicken industry. This is the first detailed report of the natural outbreaks and experimental reproduction of ND in geese, providing evidence that geese could play an important role in the epidemiology of ND.

The isolation, pathogenesis, diagnosis, transmission, and control of avian bornavirus and proventricular dilatation disease

Proventricular dilatation disease (PDD) is a common infectious neurologic disease of birds comprising a dilatation of the proventriculus by ingested food as a result of defects in intestinal motility, which affects more than 50 species of psittacines, and is also known as Macaw wasting disease, neuropathic ganglioneuritis, or lymphoplasmacytic ganglioneuritis. Definitive diagnosis of PDD has been problematic due to the inconsistent distribution of lesions. Since its discovery, avian bornavirus (ABV) has been successfully cultured from the brains of psittacines diagnosed with PDD, providing a source of antigen for serologic assays and nucleic acid for molecular assays. This article provides evidence that ABV is the etiologic agent of PDD. Recent findings on the transmission, epidemiology, pathogenesis, diagnosis, and control of ABV infection and PDD are also reviewed.

Genomic characterization of a proventriculitis-associated infectious bronchitis coronavirus

Transmissible proventriculitis associated with infectious bronchitis virus (IBV) was at first seen in eastern China in mid-1995, and is now endemic in China. Herein, the complete genome sequence of a proventiculitis-associated infectious bronchitis coronavirus (ZJ971) was sequenced and analyzed. Compared with the genome of the vaccine strain H120, ZJ971 had 54 nucleotide substitutions and a deletion in the 3′-UTR. The substitutions were in the regions of nsp2–nsp5, nsp7, nsp12, nsp13, nsp15, S and N genes, and the untranslating region. The results indicated that ZJ971 could be a variant of IBV strain H120.

Disseminated Aspergillus flavus infection in broiler breeder pullets

Increased morbidity and mortality occurred in a 5-wk-old broiler breeder replacement pullet flock. The affected broiler pullet flock was housed on the first floor of a two-story confinement building. Mortality increased to 0.1%/day compared to the flock on the second floor, which had mortality levels of less than 0.01%/day. Clinical signs in the affected chickens included inactivity, decreased response to stimuli, and anorexia. No respiratory or neurologic signs were observed. On necropsy, affected pullets were dehydrated and emaciated and had disseminated variably sized single or multiple heterophilic granulomas that contained intralesional septate and branching fungal hyphae. Lesions were extensive around the base of the heart in the thoracic inlet and in the kidneys. Other affected organs included eyelid, muscle, proventriculus, ventriculus, intestine, liver, spleen, lung, and heart. Aspergillus flavus was cultured from the visceral granulomas. The source of flock exposure to the organism was not determined.

Transmissible proventriculitis in broilers

This article reviews transmissible proventriculitis in poultry from 1971 to 2006. The disease is important in commercial broilers worldwide, resulting in reduced profits. The aetiology of this disease is unknown and different clinical presentations often result in a confused or complicated diagnosis. The lesion of enlarged proventriculus is often referred to as proventriculitis. However, the term proventriculitis can only be used correctly when there is microscopic evidence of inflammation of the proventriculus glands. Infectious and non-infectious causes of proventriculitis, with major emphasis on the infectious or transmissible causes, are reviewed.

Experimental reproduction of transmissible viral proventriculitis by infection of chickens with a novel adenovirus-like virus (isolate R11/3)

Transmissible viral proventriculitis (TVP) was experimentally reproduced in 2-wk-old specific-pathogen-free chickens and commercial broiler chickens by eyedrop inoculation of adenovirus-like virus (AdLV), isolate R1 1/3. No clinical signs and no weight gain depression were observed in chickens inoculated with AdLV (R11/3); however, gross and microscopic lesions characteristic of TVP were present in proventriculi of inoculated chickens. Proventriculi of AdLV (R11/3)-inoculated chickens were markedly enlarged, compared with sham-inoculated controls, by day 7 postinoculation (PI). Microscopic lesions in proventriculi of inoculated chickens were detected beginning on day 3 PI and consisted of degeneration and necrosis of glandular epithelium, ductal epithelial hyperplasia, replacement of glandular epithelium with ductal epithelium, and diffuse interstitial lymphoid infiltration; no microscopic lesions were observed in other tissues. AdLV (R11/3) antigens were detected in proventriculi by immunohistochemistry on days 3-10 PI in inoculated SPF chickens and days 3-21 PI in inoculated commercial broiler chickens; no viral antigens were detected in other tissues. AdLV (R11/3) was reisolated from proventriculi of inoculated SPF and commercial broiler chickens on days 5 and 7 PI. No virus, viral antigens, or lesions were detected in proventriculi collected from sham-inoculated chickens. These findings indicate an etiologic role for AdLV (R11/3) in TVP.

Proventricular dilatation disease: an emerging exotic disease of parrots in Australia

Proventricular dilatation disease is a viral disease seen as a segmental neuropathy in parrots. It has always been believed to be a disease exotic to Australia, with the only reported case being a legally imported Green Wing Macaw (Ara chloroptera) in 1993. This paper reports a cluster of cases seen in south‐east Queensland in 2005 to 2006. Clinical signs, autopsy findings and histopathological findings are described. No pattern or common source for these cases could be identified. The implications for Australian aviculture and avifauna are discussed.

West Nile virus-associated mortality events in domestic Chukar partridges (Alectoris chukar) and domestic Impeyan pheasants (Lophophorus impeyanus)

West Nile virus (WNV) infection was diagnosed in captive juvenile chukars (Alectoris chukar), and captive juvenile Impeyan pheasants (Lophophorus impeyanus) on the basis of necropsy, histopathology, polymerase chain reaction, and immunohistochemistry. The chukars were kept in a game bird farm that experienced two outbreaks with approximately 25% mortality in hundreds of chukars between September and October 2002 and during the same months in 2003. The submitted pheasants were part of a group of 15 juvenile Impeyan pheasants that all died within approximately 2 wk at the end of August 2002. The macroscopic lesions in the pheasants were dominated by mucosal hemorrhage at the proventricular to ventricular junction and cecal ulcers, whereas the gross lesions in the chukar partridges were nonspecific. The predominant microscopic lesion in the chukar partridges was myocardial necrosis, whereas fibrinous and necrotizing splenitis was prominent in the pheasants. Viral antigen was usually widespread in animals of both species. Spontaneously occurring WNV infection should be considered a differential diagnosis in cases of mortality among select species of galliform birds.

An interesting neurologic case in a lovebird (Agapornis fisheri)

The pathogenic agent of proventricular dilatation disease causes a lymphoplasmacytic inflammation of the central peripheral nervous systems. Usually, the splanchnic nerves are affected, with resultant gastrointestinal dysfunction and clinical signs related to this. When the brain, spinal cord, and peripheral nerves are affected, neurologic signs may be present in various degrees. This case emphasizes the importance of necropsy and histopathologic examination in making a diagnosis and treatment.

Disseminated Visceral Coccidiosis in a Wild White-naped Crane (Grus vipio)

Disseminated visceral coccidiosis (DVC) was unexpectedly recognized in a wild white-naped crane (Grus vipio) killed by phosphamidon insecticide. On gross pathologic examination, widely disseminated white nodules were found on the serosa of the pro-ventriculus, gizzard, and intestine, as well as on the surface and in the parenchyma of liver, spleen, and cardiac muscle. Microscopically, asexual stages of a coccidia were observed in some nodules. However, the species of coccidia could not be determined because no oocysts were found on fecal examination. This is believed to be the first reported case of DVC in a wild white-naped crane infected with Eimeria spp.

Proliferative response by the ostrich proventriculus in idiopathic gastric stasis: a case report

In this report, the late clinical, necropsy, and histopathological findings of idiopathic gastric stasis in an ostrich are described, with special attention to the proventriculus. An ostrich with clinical signs of gastric stasis was brought to our clinic in a state of impending death that could not be reversed with emergency medical care. At necropsy, the koilin layer of the gizzard was uneven without ulcerations. The proventriculus was distended with food items without impaction and mucosal lesions. None of the most typical aetiological factors including foreign objects, Macrorhabdus ornithogaster and parasitic infection with Libyostrongylus douglassii was present. Histologically, the proventriculus was characterised by hyperplastic mucosa with luminal buds and necrotic cells in the lumen. Immunochemistry for proliferating cell nuclear antigen (PCNA) revealed a high rate of proliferation in epithelial cells of the glandular and mucosal lining in the proventriculus neighbouring the affected gizzard: approximately 88.6% of the cells were immunoreactive as compared to 34.4% of the cells in control ostriches used for comparison. In conclusion, in the absence of gizzard contraction, the mucosal lining of the proventriculus is hyperplastic with a high rate of proliferation that may help compensate the distension due to the accumulation of food items.

[Case report: Libyostrongylus douglassii-associated proventriculitis in ostriches in Germany]

Cases of Libyostrongylus douglassii-associated proventriculitis in an adult female ostrich and two ostrich chicks occurring on two farms in different federal states of Germany are described. The adult bird was recently bought and kept under quarantaine conditions without contact to other animals of the herd. Without developing clinical signs of illness, the animal died. At necropsy, typical lesions of wireworm infection were found. The lining of the stomach had a moth-eaten appearance. Massive amounts of adult stages of trichostrongyloid nematodes were diagnosed in histological specimens of the proventricular mucosa and under the koilin layer of the ventriculus. The worms were isolated from the proventriculus and identified as L. douglassii. The feces of the bird contained high amounts of typical eggs of the worms with a medium size of approximately 70 x 40 microm. A polyphasic degeneration of heart and skeletal muscle was diagnosed in addition to the wireworm infection and interpreted to be a result of a malnutrition (Vit. E-/selenium deficiency). The ostrich chicks were reared on another farm and submitted for necropsy because of high mortality (8 out of 12 chicks died). A massive invasion of the proventricular mucosa with L. douglassi was macroscopically and histologically detected at necropsy of the anemic birds.

Reproduction of proventriculitis in commercial and specific-pathogen-free broiler chickens

Proventriculitis was studied by experimentally reproducing the disease in broiler chickens. One-day-old infectious bursal disease virus (IBDV) and infectious bronchitis virus (IBV) antibody positive commercial broilers and 1-day-old antibody negative specific-pathogen-free (SPF) broilers were orally gavaged with proventricular homogenates produced from the proventriculi of broilers with proventriculitis. At 7 and 14 days, both commercial and SPF broilers had enlargement of the proventriculus with necrosis of the glandular epithelium and lymphocytic infiltrates in the proventricular glands. SPF broilers exposed to the proventricular homogenates developed infectious bursal disease, and IBDV was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). They also were positive by RT-PCR to IBV and developed nephritis. Commercial broilers developed mild nephritis but not bursal disease and were negative for IBDV and positive for IBV by RT-PCR. Both homogenate-inoculated commercial and SPF chickens were negative for reovirus and Newcastle disease virus by RT-PCR and variably positive for adenovirus by PCR. Bacteria were not identified in histologic sections, nor were they isolated from affected proventriculi. Indirect fluorescent antibody assay using convalescent sera detected intracytoplasmic staining in the proventricular glandular epithelial cells. Examination of thin sections of proventriculi using electron microscopy identified virus-like particles approximately 120 nm in diameter within the cytoplasm of these cells at 7 days after inoculation. Passage of proventricular homogenate filtrates in chicken embryos for virus isolation caused stunting, and allantoic fluid from these eggs was positive for IBV by RT-PCR.

Partial characterization of an adenovirus-like virus isolated from broiler chickens with transmissible viral proventriculitis

Transmissible viral proventriculitis (TVP) was experimentally reproduced in specific-pathogen-free chickens using a homogenate of proventricular tissue obtained from TVP-affected commercial broiler chickens. Thin-section electron microscopy revealed intranuclear, approximately 70-nanometer (nm), adenovirus-like viruses (AdLV) within proventricular lesions. The AdLV, designated AdLV (R11/3), could not be propagated using various avian and mammalian cell cultures or by inoculation of embryonated chicken eggs by yolk, allantoic, or chorioallantoic membrane routes. However, AdLV (R11/3) was successfully propagated by amniotic inoculation of embryonated chicken eggs, with detection of the virus in proventriculi and intestinal contents of hatched 2-day-old chicks (8 days postinoculation). Virus propagation was evident in in ovo-inoculated chicks by (1) gross and microscopic lesions in proventriculi consistent with TVP, (2) immunohistochemical localization of AdLV (R11/3) antigens in proventricular epithelium, (3) thin-section electron microscopic detection of intranuclear, approximately 70-nm AdLVs within proventricular epithelium, and (4) negative-stain electron microscopic detection of extracellular, approximately 70-nm AdLVs in intestinal contents. Indirect immunofluorescence and polymerase chain reaction procedures that specifically recognize groups I, II, and III avian adenoviruses failed to recognize AdLV (R11/3). The findings suggest an etiologic role for AdLV (R11/3) in TVP and indicate that this virus is distinct from known avian adenoviruses.

Disseminated visceral coccidiosis and cloacal cryptosporidiosis in a Japanese white-naped crane (Grus vipio)

A 4-mo-old male Japanese white-naped crane (Grus vipio) kept in an outdoor exhibit at the Everland Zoological Gardens in Korea became depressed and developed anorexia, weight loss, and diarrhea. Death of this bird was associated with an overwhelming systemic infection by an intracellular coccidian parasite, which resulted in necrosis and granulomatous inflammation in a number of major organs, including the intestine, liver, spleen, and kidney. Coccidian parasite-laden macrophages were commonly found in the blood vessels of these organs. Using electron microscopy and polymerase chain reaction assays, the parasite was identified as Eimeria sp. The bird was also infected with Cryptosporidium sp., which suggests an immunosuppressed state, although the cause of such suppression was not identified. Our findings suggest that an initial Eimeria sp. intestinal infection spread to other organs through the blood vessels, with the immunosuppressed state possibly contributing to a rapid hematogenous transmission. To our knowledge, this is the first report of disseminated visceral coccidiosis caused by Eimeria sp. in a captive Japanese white-naped crane.

Proventriculitis in broiler chickens: immunohistochemical characterization of the lymphocytes infiltrating the proventricular glands

Broiler chickens with transmissible proventriculitis have severe lymphocytic infiltration of the proventricular glands. The distribution of T cells and B cells in these infiltrates was studied histopathologically, and their identity was confirmed immunohistochemically (CD3, CD4, CD8, and B cells). To reproduce this disease, 1-day-old commercial boilers were orally gavaged with homogenized proventriculi from broilers with proventriculitis. Resulting lesions were examined at both acute (7 days postinoculation [i]) and chronic (14 and 21 dpi) time points. Lymphocytic infiltrates in the proventricular glands and the mucosal lamina propria were present at all time points and were most prominent and demarcated at 14 dpi. T and B lymphocytes were present during acute and chronic proventriculitis, but their distribution varied within the glands. Lymphocytic infiltrates in the proventricular glands and in the lamina propria were predominantly CD3+T cells, and most of these were also CD8+. B cells and CD4+ T cells formed aggregates in chronic proventriculitis. Thus, both cell-mediated and humoral immune responses are induced during transmissible proventriculitis, and the cell-mediated immune response is morphologically greater.

Proventriculitis in broiler chickens: effects of immunosuppression

Proventriculitis in broilers causes carcass condemnation when swollen proventriculi tear during evisceration. The cause of this proventriculitis is unknown, but several infectious agents have been associated with it. One such agent, infectious bursal disease virus (IBDV), has been implicated as a cause of proventriculitis, but a direct effect of this virus on the proventriculus has not been proven. The role of IBDV in proventriculitis may be indirect as a result of its ability to cause immunosuppression. The objective of this study was to understand how immunosuppression affects the incidence of proventriculitis in broiler chickens. Immunosuppression was induced in commercial and specific-pathogen-free broiler chickens using chemicals (cyclophosphamide and cyclosporin) or virus (IBDV). All groups were then exposed to a proventricular homogenate produced from diseased birds. At 7 and 14 days postinoculation, the incidence of proventriculitis in these groups was compared to that produced by homogenate exposure in immunocompetent broilers. All birds exposed to the proventricular homogenate from diseased birds developed proventriculitis. Cyclophosphamide and IBDV, both B cell suppressors, did not significantly affect the incidence or characteristics of the proventriculitis observed, although they did have an effect on the size of the proventriculus at 7 days postinoculation. Chickens immunosuppressed with cyclosporin, a T cell suppressor, developed more severe lesions and had a higher incidence of proventriculitis. These findings indicate that both B and T cells are involved in the immune response against proventriculitis, but cell-mediated immunity appears to have a more important role in controlling the disease. IBDV affects both humoral and cellular immunity in the chicken, so although under experimental conditions it didn't have a major effect on proventriculitis, it may explain why control of IBDV in the field seems to reduce the incidence of proventriculitis.

Proventricular adenocarcinoma in a Humboldt penguin (Spheniscus humboldti) and a great horned owl (Bubo virginianus); identification of origin by mucin histochemistry

Cases of proventricular neoplasm in a Humboldt penguin (Spheniscus humboldti) and a great horned owl (Bubo virginianus) were observed. Microscopically, the neoplastic cells formed branching tubules or acini in both cases. Galactose oxidase-Schiff (GOS) staining revealed that the cytoplasm of the normal surface epithelium and surface mucosubstances of the proventriculus adjacent to the neoplasm were positive in both cases. The neoplastic cells in both cases were also classified as GOS-positive. Therefore, the two proventricular neoplasms in this report were diagnosed as proventricular adenocarcinoma that arose from the proventricular surface epithelium. This study suggests that the mucosubstances, which the neoplastic cells produced, were a useful index for identifying the origin of the neoplastic cells in the birds.

Mortality in Laysan Ducks (Anas laysanensis) by Emaciation Complicated by Echinuria uncinata on Laysan Island, Hawaii, 1993

In November 1993, unusual mortality occurred among endangered Laysan ducks on Laysan Island, one of the remote refugia of the Northwestern Hawaiian Islands National Wildlife Refuge (USA). Ten live ducks were emaciated, and blood samples documented anemia, heterophilia, and eosinophilia. Pathology in 13 duck carcasses revealed emaciation, marked thickening of the proventricular wall, abundant mucus, and nodules in the gastrointestinal tract. Histology revealed granulomata associated with nematodes in the proventriculus, small intestines, and body walls of nine of 10 ducks examined on histology. We suspect that low rainfall and low food abundance that year contributed to enhanced pathogenicity of parasite infection, either through increased exposure or decreased host resistance. Because the Laysan duck is found only on Laysan island and is critically endangered, translocation of this species to other islands is being considered. Given that we have not seen pathology associated with Echinuria spp. in native waterfowl on other Hawaiian Islands and given the parasite's potential to cause significant lesions in Laysan ducks, it will be important to prevent the translocation of Echinuria spp.

Infectious Bursal Disease Virus and Proventriculitis in Broiler Chickens

Acute necrotic proventriculitis is a naturally occurring disease of broiler chickens that causes proventricular rupture during routine evisceration. Although infectious bursal disease virus (IBDV) has been implicated, it has not been proven to be a direct cause of this disease. To further study the role of IBDV in proventriculitis, proventriculi and bursas were collected during both acute and chronic phases of naturally occurring proventriculitis and from chickens experimentally infected with seven different [BDV strains. All tissues were examined for IBDV by light microscopy, immunohistochemistry (IHC), and real time reverse transcriptase(RT)-polymerase chain reaction (PCR) and for apoptosis by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling method (TUNEL). Tissues from naturally occurring proventriculitis had bursal and proventricular lesions. Two out of four bursas had no IHC-stainable IBDV antigen or RT-PCR detectable IBDV sequences. No proventriculus had IBDV detectable by any of these methods. Bursas from chickens experimentally infected with IBDV had microscopically evident lesions, IBDV was detectable by IHC and RT-PCR, and strong IHC staining for apoptosis was present. Proventriculi from these experimentally exposed chickens had no lesions, low levels of IBDV detectable by IHC or RT-PCR, and very little IHC-stainable apoptosis. We conclude that naturally occurring proventriculitis can occur in the absence of IBDV and that the IBDV strains tested do not directly produce proventriculitis or induce increased proventricular apoptosis.

Gastric gross and microscopic lesions caused by the UNAM-97 variant strain of infectious bronchitis virus after the eighth passage in specific pathogen-free chicken embryos

Herein we report a description of gross and microscopic lesions found in specific pathogen-free chicken embryos caused by UNAM-97 infectious bronchitis virus (IBV) variant strain after the eighth passage. Embryos were divided into three groups and were inoculated in the chorioallantoic sac with 0.2 mL of UNAM-97, Mass 41 IBV (positive control), or sterile PBS (negative control). Forty-eight hours later the allatoic fluid was taken and used to start a cycle of eight passages through 9-d-old embryos. Seven days after the last passage, embryos were harvested and macroscopic lesions in all organs were recorded. Proventriculus and gizzard samples were obtained from all embryos and routinely processed for microscopic and ultrastructural examinations. The UNAM-97 IBV variant strain caused two macroscopic lesions uncommon for Mexican strains: thin-walled proventriculus and gizzard, as well as urate accumulation within an extra-embryonic peritoneal sac, leaving the body through the umbilical duct and accompanied by the yolk sac. At microscopic level, two relevant findings were observed to be produced by this variant. In the proventriculus, there was a decrease in the gland papillary branching, while the gizzard showed a significant reduction in mucosa thickness and tubular-to-proliferative-cell ratio, as well as an absence of hyaline secretion in the lumen. Electrodense material scattered in proventricular and gizzard cells was observed, with a structure consistent with that of coronaviruses. These pathological chicken embryo findings have not been reported as being caused by other IBV strains in Mexico.

Viral and bacterial agents associated with experimental transmission of infectious proventriculitis of broiler chickens

Proventriculitis of broilers can be reproduced by oral inoculation of day-old chicks with a proventricular homogenate from affected 3-wk-old broilers. The objective of the following studies was to isolate from this homogenate viral and bacterial isolates that could produce proventriculitis. A monoclonal antibody to infectious bursal disease virus (IBDV) was used to precipitate virus from the homogenate. A primary chicken digestive tract cell culture system was also used to isolate virus from a 0.2-microm filtrate of the homogenate, and a bacterium was also isolated from the homogenate. In trial 1, day-old birds were orally inoculated with either proventriculus homogenate or monoclonal antibody immunoprecipitated IBDV (MAB-IBDV). At 4, 7, 14, and 21 days postinfection (PI), 12 birds from each treatment group were subjected to necropsy. In trial 2, day-old birds were orally inoculated with either infectious proventriculus homogenate, suspect virus isolated in cell culture and propagated in embryo livers and spleens, or a bacterial isolate. Twelve birds from each treatment were subjected to necropsy at days 7, 14, 21, and 28 PI. In trial 3, treatments were maintained in negative pressure isolation chambers, and an additional treatment included virus plus bacterial isolate. Twenty-four birds from each treatment were subjected to necropsy at day 21 PI. In trial 1, infectious homogenate decreased body weight and relative gizzard weights at 4, 7, 14, and 21 days PI. Proventriculus relative weight was increased at days 7, 14, and 21 PI, and proventriculus lesion scores were increased at days 14 and 21 PI. Bursa/spleen weight ratios were decreased at day 14, and feed conversion was increased at days 4 and 21. The MAB-IBDV treatment decreased proventriculus and gizzard relative weights at day 4 PI, increased proventriculus lesion scores and bursa/spleen weight ratios at day 14, and decreased heterophil/lymphocyte ratios at day 21. In trial 2, all infected birds had significantly higher mean relative proventriculus weights at 21 days PI and had higher 4-wk mean proventriculus scores as compared with both control groups. In trial 3, birds treated with homogenate and birds treated with both suspect virus and the bacterial isolate had significantly higher proventriculus lesion scores; higher relative weights of proventriculus, gizzard, liver, and heart; lower body weights; and lower relative bursa weights compared with the saline control group. These studies suggest that infectious proventriculitis has a complex etiology involving both viral and bacterial infection.

Immunohistochemical localization of avian leukosis virus subgroup J in tissues from naturally infected chickens

The tissue tropism of avian leukosis virus (ALV) subgroup J (ALV-J) was investigated in congenitally infected broiler chickens by an immunohistochemistry technique detecting gp85 viral glycoprotein. All organs examined contained detectable antigen. The most intense staining was in the adrenal gland, heart, kidney, and proventriculus. Intense staining for viral antigen in the heart may explain the ability of ALVs to cause cardiomyopathy. Although recent investigations failed to demonstrate specific viral staining in bone marrow from infected chickens, we were able to show moderate staining in myelocytic precursor cells in bone marrow. This finding agrees with previous work showing cell cultures of bone marrow are susceptible to ALV-J infection and the tendency of subgroup J to predominantly induce myeloid rather than lymphoid neoplasms.

Effects of biogenic amines on growth and the incidence of proventricular lesions in broiler chickens

Biogenic amines have been implicated in a malabsorption syndrome characterized by decreases in feed efficiency and enlargement of the proventriculus. Two studies were conducted to determine the effects of two common biogenic amines, histamine (HIS) and cadaverine (CAD), on broiler growth and the incidence of pathologies associated with proventriculitis. In the first experiment, broiler chicks were fed diets containing 0, 0.01, 0.05, 0.1, and 0.2% HIS, and in the second experiment chicks were fed diets containing 0, 0.1, and 0.2% HIS, 0.1% CAD, or a combination of 0.1% HIS and 0.1% CAD. Histamine at 0.1 and 0.2% or the combination of HIS and CAD (0.1% each) reduced body weight and feed conversion at 21 d of age. Histamine (0.2%) or the combination of 0.1% HIS and 0.1% CAD increased the circumference of the gastric isthmus 14 and 16%, respectively, and the relative weight of the proventriculus by 21 and 36%, respectively. Histamine and CAD increased the total number, incidence, and severity of gizzard erosion and proventricular ulcers (plaques), and decreased the prominence of gastric papillae by 9 to 108%, depending on the lesion and level of biogenic amine. Dietary HIS (0.2%) increased putrescine by 91% and spermidine by 41% in proventriculus, and dietary CAD increased tissue CAD to detectable levels. Analysis of 49 commercially available, animal by-product feedstuffs suggests that if biogenic amines were the singular cause of proventriculitis, the current industry levels of dietary animal protein (5 to 10%) would not compromise growth performance.

[Megabacteria-associated proventriculitis in poultry in the state of Brandenburg, Germany]

During the second half of the year 2000, we have diagnosed a megabacterial-associated proventriculitis in 13 laying hens and 4 cocks from 14 different flocks and one turkey. All birds were submitted for necropsy because of progressive runting, increased mortality and poor laying performance in the herds. Routine diagnostic workup included necropsy, histology, bacteriology, parasitology and virology. At necropsy, the proventricular of the birds were enlarged. The walls were thickened and the mucosa covered with cloudy, grey-white mucus. Petechial haemorrhages and ulcerations predominantly at the proventricular-ventricular junction and sloughing of the necrotic koilin layer of the ventriculus were inconsistently present. Megabacteria (approximately 40-50 by 2-4 microns, gram-positive to gram-labile, rod-shaped organisms) were present in large numbers in touch preparations of the proventricular mucosal surface. In some of the preparations, the megabacteria showed a branching pattern similar to fungal hyphae. By histopathology, all birds showed moderate to marked, diffuse lympho-plasmacytic proventriculitis. Heterophilic exudation was present in the terminal portion of the proventriculus, where the greatest numbers of the organism were found. Megabacteria were present in the mucus covering the mucosal surface and the lumina of the superficial proventricular crypts, occasionally invading the luminal epithelium. Megabacterial infection was in general associated with other diseases such as avian tuberculosis, salmonellosis, coccidiosis, chlamydiosis and various other bacterial and parasitic infections. Only in one hen no other concurrent infectious organism was detected. The turkey had histomoniasis. Wild birds were regarded as probable source of infection, since all affected birds were kept under conditions allowing contact to wild birds and we have diagnosed megabacterial infections in wild-living green finches earlier.

Resistance to Marek's disease herpesvirus-induced lymphoma is multiphasic and dependent on host genotype

Genotype-dependent differences in Marek's disease (MD) susceptibility were identified using 14-day-old line N and 6(1) (resistant) and 151 and 7(2) (susceptible) inbred chickens infected with HPRS-16 MD virus (MDV). All line 72 chickens developed progressive MD. Line 15I had fluctuating MD-specific clinical signs and individuals recovered. A novel histologic scoring system enabled indices to be calculated for lymphocyte infiltration into nonlymphoid organs. All genotypes had increased mean lesion scores (MLSs) and mean total lesion scores after MDV infection. These differed quantitatively and qualitatively between the genotypes. Lines 6(1) and 7(2) had a similar MLS distribution in the cytolytic phase, although scores were greater in line 7(2). At the time lymphomas were visible in line 7(2), histologic lesions in line 6(1) were regressing. AV37+ cells were present in similar numbers in all genotypes in the cytolytic phase, suggesting that neoplastically transformed cells were present in all genotypes regardless of MD susceptibility. After the cytolytic phase, AV37+ cell numbers increased in lines 7(2) and 15I but decreased in lines 6(1) and N. In the cytolytic and latent phases, in all genotypes, most infiltrating cells were CD4+. After this time, line 7(2) and 15I lesions increased in size and most cells were CD4+; line 6(1) and N lesions decreased in size and most cells were CD8+. In all genotypes, AV37 immunostaining was weak in lesions with many CD8+ cells, suggesting that AV37 antigen expression or AV37+ cells were controlled by CD8+ cells. The rank order, determined by clinical signs and pathology, for MD susceptibility (highest to lowest) was 7(2) > 15I > 6(1) > N.

A comparative study of the pathogenesis of malabsorption syndrome in broilers

Five malabsorption syndrome (MAS) homogenates from The Netherlands and Germany were used to reproduce MAS in broilers. We studied the histopathology after inoculation of 1-day-old broiler chicks and the agents that might be involved. Generally, the MAS homogenates induced signs that differed in severity and pathobiology. We could distinguish and classify the inoculated groups best by histopathology: proventriculitis, lesions in the small intestines in combination with proventriculitis, or lesions of the small intestines only. Lesions in the small intestine had more impact on weight gain depression than lesions in the proventriculus. In three out of five inoculated groups, microscopic lesions of the pancreas were found. Reovirus was detected in the inoculated groups by virus isolation and seroconversion, and reoviral antigen was detected by immunohistochemistry of the small intestine. Also, enteroviruslike particles were detected in three of the five inoculated groups, although not in the most affected group. Additionally, bacteriophages and bacteria (hemolytic Escherichia coli, Pasteurella hemolytica, and Enterococcus durans) were isolated from inoculated chicks. The role these agents play in pathogenesis of MAS is still unsolved.

Effects of biogenic amines in broiler chickens

Biogenic amines in spoiled animal by-product feeds have been implicated in causing poor performance and intestinal lesions in broilers. This study was designed to determine if biogenic amines, at the concentrations found in animal by-product meals, would reduce performance in broilers or cause lesions. Twelve treatments were used in a 2 x 6 factorial arrangement with the main effects being either a corn-soybean meal diet or a corn-soybean meal diet with 10% animal by-products added and either no amines added or added levels of phenylethylamine (4.8 mg/kg), putrescine (49 mg/kg), cadaverine (107 mg/kg), histamine (131 mg/kg), or a combination of all these amines. Levels of biogenic amines used in this study simulated those found in areas with reported problems attributed to biogenic amines. Broilers were monitored for performance, gross lesions, and histologic evidence of lesions at 2, 4, and 6 wk. No consistent effects were observed on performance, and by the conclusion of the trial, no statistical differences were noted in the performance of any of the treatments. No gross lesions were observed on a consistent basis in any of the treatments. Histopathology was likewise unremarkable. On the basis of this study, it would appear that these four biogenic amines, at levels detected in the United States, do not pose a serious health concern for the broiler industry.

[Proventriculitis in domestic fowl (Gallus gallus var. dom. L., 1758) caused by megabacteria]

Three cases of a disease similar to going light syndrome in budgerigars in a flock of young laying hens in Turkey are reported. In all cases megabacteria in association with E. coli could be isolated. The causing agent appeared to be large, rod-shaped, gram-positive or gram-labil, and catalase test positive bacteria with cytochromoxydase activity. Subcultivation of these bacteria could not be achieved.

Hydropericardium syndrome (HPS) in India: a preliminary study on the causative agent and control of the disease by inactivated autogenous vaccine

Hydropericardium syndrome (HPS) in broiler birds of 3 to 6 weeks of age was recorded for the first time in the Haldwani area of Nainital district (UP) in India in November, 1994. The overall mortality in 6 poultry farms was 61.62 per cent. The disease was experimentally transmitted by bacteria free infected liver homogenate extract passed through membrane filters of 0.22 and 0.1 mu APD. The aetiological agent was inactivated by heat treatment at 56 degrees C for one hour and 80 degrees C for 10 min. A precipitin band was demonstrated in agar gel immunodiffusion and counter immunoelectrophoresis using infected liver homogenate extract as antigen and homologous antisera raised in the laboratory. The disease was effectively controlled by formalinised and heat inactivated autogenous vaccine prepared from the infected livers of birds which died of natural infection.

Multiple intussusceptions in a juvenile rhea (Rhea americana) with proventricular impaction

Multiple intussusceptions of the small intestine were identified in a 4-mo-old rhea (Rhea americana) that died acutely after chronically poor growth. The chick was one of a group of 12 chicks that exhibited musculoskeletal deformities, poor growth, and subsequent death. Gross necropsy findings of this chick revealed proventricular impaction by sticks and stones accompanied by multiple intussusceptions of the small intestine. This finding identifies a disease process that may afflict ratites when raised for production and that may complicate treatment of proventricular impaction.

Effects of feeding Fusarium moniliforme culture material, containing known levels of fumonisin B1, in the young turkey poult

The effects of feeding Fusarium moniliforme culture material, containing known concentrations of fumonisin B1 (FB1), were studied in turkey poults. Day-old poults were allotted randomly to dietary treatments containing 0, 0.41, 0.82, 1.23, 1.64. 2.87, 4.10, 5.33, 6.56, and 7.79% fumonisin culture material (FCM). These levels of FCM supplied 0, 25, 50, 75, 100, 175, 250, 325, 400, and 475 mg FB1/kg of feed. Each dietary treatment was fed to six pen replicates of six poults each for 21 d. Poults fed FCM that supplied 325 to 475 mg FB1/kg diet had lower (P < 0.05) feed intakes and BW gains. Increased (P < 0.05) liver and pancreas weights were observed in poults fed FCM that supplied > or = to 175 mg FB1/kg. Poults fed FCM that supplied 400 and 475 mg FB1/kg diet had increased (P < 0.05) red blood cell counts and increased (P < 0.05) serum concentrations of gamma glutamyl transferase and aspartate aminotransferase. Compared with controls, poults fed FCM that supplied 25, and 75 to 475 mg FB1/kg had increased (P < 0.05) liver sphinganine:sphingosine ratios. Hepatocellular hyperplasia was mild at 75 and 100 mg FB1/kg diet, moderate to severe at 250 mg/kg FB1, and severe at 325 to 475 mg FB1/kg. Multifocal to generalized loss of cross striations and thinning of cardiomyocytes was observed in poults fed FCM that supplied 475 mg FB1/kg diet. Results indicated that diets containing < or = to 1.23% FCM that supplied > or = to 75 mg FB1 /kg are toxic to young turkeys.

An immunohistochemical study of the pathogenesis of virulent viscerotropic Newcastle disease in chickens

Ten specific pathogen-free cockerels aged 8-12 months were infected by ocular instillation of 2 x 10(7) embryo-lethal doses 50% of a virulent viscerotropic strain of Newcastle disease virus (Fontana 1083 strain). The birds were killed at 24-h intervals after infection and tissues were collected for histological and immunohistochemical evaluation. The infection ran an acute course, severe clinical disease occurring within 72 h of infection. By gross and histological examination, the most severe damage detected was found to occur in lymphoid areas in a number of tissues. The greatest amounts of viral antigen detected occurred in the proventriculus, small intestine, spleen, thymus and eyelid. Immunohistochemical labelling was confined to large mononuclear cells.

The effect of dietary copper sulfate on infectious proventriculitis

Oral inoculation of day-old broiler chicks with a crude homogenate of affected proventricular tissue, or the same homogenate filtered through a .2 micron filter caused proventricular lesions similar to those responsible for carcass contamination of broilers at processing. Dietary copper sulfate (CUS) has also been shown to produce similar lesions. In this study, we investigated the interaction between crude proventriculus homogenate or filtered proventriculus homogenate and 1 g/kg CUS added to a standard chicken diet. Cobb x Cobb female broiler chicks were distributed into six groups with four replicate battery pens per group. Birds were fed either a standard broiler starter diet or the same diet with 1 g/kg CUS. Each dietary treatment was inoculated per os with 1 mL of either sterile saline, unfiltered homogenate, or filtered homogenate. Both crude and filtered homogenates had a much stronger affect on proventriculus score than did Cu by itself, resulting in no interaction between either homogenate or filtrate and CUS. There was a significant and possibly antagonistic interaction on proventriculus relative weights in the CUS by filtrate group during Week 1 and a synergistic interaction in the CUS by homogenate group during Week 4. Body weights were decreased in birds fed homogenate or CUS, but not in birds fed filtrate. There was a protective effect shown by filtrate on body weight of birds fed both filtrate and CUS only during Week 1. There was a synergistic decrease in body weight of birds fed homogenate and CUS during Week 2. Overall feed conversion efficiency was significantly decreased in the homogenate treatment (P = .04) and decreased in the birds fed CUS (P = .1). There was a (4.2 vs 2.3) (P = .1) decrease in feed conversion efficiency in birds fed both homogenate and CUS. Natural exposure to low levels of the infectious agent present in the homogenates may interact with excess dietary CUS, resulting in increased proventriculus size and decrease in body weight and feed conversion efficiency.

Experimental reproduction of proventriculitis using homogenates of proventricular tissue

Proventriculitis is a problem affecting the processing of broiler carcasses, particularly those processed at 4 to 5 wk of age. The proventriculus and the gastric isthmus connecting the proventriculus to the gizzard are enlarged and swollen and often rupture during processing, causing carcass contamination. This study suggested that a filterable agent found in homogenated proventriculi can cause lesions similar to those seen in field cases. Proventriculitis was produced independently of an effect on growth, and only unfiltered homogenate caused stunting. Field birds with severe proventriculitis were shown to have increased body weights compared with birds without proventriculitis or with milder lesions. Intestinal weakness was not associated with proventriculitis and field birds with the most severe proventriculitis had stronger intestines. Although infectious proventriculitis has generally been reported as one of the lesions associated with stunting syndrome, these data suggest that it may have an independent etiology.

An occurrence of stomach impaction in ostriches (Struthio camelus) on a farm in Zambia associated with high mortality

Fifty-one ostriches (Struthio camelus), 6 weeks old, were imported from Namibia and introduced onto a farm in Zambia. Soon after introduction, most of the birds manifested clinical symptoms such as anorexia and diarrhea and 19 birds died within 1 week. The proventriculus and gizzard in the 4 dead birds were full of solid masses of lucerne hay mixed with maize and consequently the gizzard was extremely impacted by them. Neither pathogenic bacteria nor parasites were detected from the autopsied birds and 8 fecal samples. After diagnosis, the ostrich feed was improved and a demulcent was given immediately; then all ostriches that remained on the farm recovered. In conclusion, these data confirmed that the present case was stomach impaction in ostriches.

Tetrameres (Petrowimeres) striata in ducks

Tetrameres (Petrowimeres) striata is an uncommon and incompletely described nematode from North American and Eurasian waterfowl. Specimens collected from mallards (Anas platyrhynchos) from the Playa Lakes Region (PLR) in western Texas (USA), the mottled duck (A. platyrhynchos fulvigula) in Florida (USA), the mallard in the Amur River Basin of eastern Russia and the blue-winged teal (Anas discors) from western Texas (USA) provide the basis for redescription of T. (P.) striata. This species is differentiated from the closely related T. (P.) zakharowi and T. (P.) galericulata by the size of the left spicule and the prominent cuff on the proximal end of the right spicule. In mallards from the PLR, one to several adult males and a single female occurred within distended mucosal glands or, more rarely, in cystic cavities in the submucosal tissue of the proventriculus; intensities ranged from one to seven nematodes per host (mean +/- SE = 2.9 +/- 0.8). Infected proventricular gland mucosae were compressed as a result of pressure atrophy by the large gravid females. In addition to nematodes, some lesions also contained necrotic debris with inflammatory cells and were surrounded by an intense inflammatory response of eosinophils, macrophages, lymphocytes, epithelioid cells and fibroblasts. Other lesions had little or no inflammatory response. Lesions in the submucosa were surrounded by a thin fibrous cyst with or without adjacent inflammatory cells.

Experimental candidiasis in Japanese quail: pathological changes

Candidiasis was experimentally produced in young Japanese quail by oral administration of Candida albicans cells. Lesions were confined to upper digestive tract with most characteristic changes occurring on the mucosa of crop. No lesions were observed in other tissues of the body. The initial changes in the crop were characterized by thickening and yellowish-white necrotic plaques on the mucosa. From 10th day onwards, there was marked thickening and corrugations of the crop mucosa giving it a typical 'turkish towel' appearance. Varying degree of mucosal swelling was also observed in the oesophagus and proventriculus. Two of the infected birds also revealed yellowish-white necrotic plaques on the tongue at 7th and 10th day post-infection. The prominent microscopic lesions in the crop and tongue consisted of hyperkeratosis and parakeratosis with congestion of the subepithelial tissues. Varying degree of parakeratosis and epithelial hyperplasia coupled with subepithelial oedema and hypertrophy of glands was observed in the oesophagus. The proventriculus and small intestine revealed congestion, oedema, mild to marked goblet cell hyperplasia and focal epithelial sloughing. Fungal elements could be demonstrated in the sections of tongue up to 10 days while in crop up to 14 days post-infection. Reisolation of the fungus was consistently achieved from the crop of infected birds throughout the duration of the experiment.

Myocarditis as a component of psittacine proventricular dilatation syndrome in a Patagonian conure

Psittacine proventricular dilatation syndrome was diagnosed at necropsy in a Patagonian conure. Gross and histopathological lesions in the proventriculus, ventriculus, and brain were similar to those previously reported. In addition, severe myocarditis was a prominent feature of this case, a finding not previously defined as a significant component of the condition.