Detection of Aphanomyces invadans and epizootic ulcerative syndrome in the Murray-Darling drainage

Epizootic ulcerative syndrome was diagnosed, and the presence of Aphanomyces invadans confirmed, from an outbreak of clinical disease in wild-caught bony bream (Nematalosa erebi) from the Darling River near Bourke, in New South Wales, Australia, during 2008. This confirms a significant extension of the agent beyond its historical range.

Some observations on naturally occurring neoplasms of domestic fowls in the State of Victoria, Australia (1977-87)

In the 10 years to November 1987, 33 different types of naturally occurring neoplasms were diagnosed in 2281 domestic fowls submitted for necropsy examination. The most prevalent type was lymphoma (1825/2281 = 80%) including two cases in chickens from a flock free from Marek's disease virus, exogenous avian leukosis viruses and reticuloendotheliosis virus; the remaining lymphomas were diagnosed on gross and/or histological criteria as Marek's disease (1069) or lymphoid leukosis (754). Of the non-lymphoid neoplasms, leiomyomas of the ventral ligament of the oviduct (99) were the most common followed closely by metastatic abdominal adenocarcinomas (93) and haemangiomas or haemangiosarcomas (91). A large number of fibromas and fibrosarcomas (40), and a smaller number of myxomas and myxosarcomas (17) were observed. Three fibrosarcomas and two myxosarcomas were presented as metastatic abdominal neoplasms, and two fibromas and seven myxomas were found on the rostral extremity of the upper beak of hens, including five cases of myxoma from one flock. Other less prevalent neoplasms described were myelocytomas or myeloblastomas (12), avian keratoacanthomas (11), granulosa-theca cell tumours (11), oviduct adenomatosis and adenocarcinomas (10) and ovarian adenocarcinomas (8). Small numbers of some neoplasms or well-characterized variants were encountered, namely histiocytic sarcomas (5), lipomas (4), liposarcomas (2), reticulum cell sarcomas (3), plasmacytomas (3), intracutaneous keratinizing epitheliomas (3), feather folliculomas (2), proventricular adenomas (2), hepatocellular adenocarcinomas (2), cholangiocellular adenomas and adenocarcinomas (6), pancreatic adenocarcinomas (3), nephroblastomas (7), astrocytomas (5), pinealomas (3), Schwannomas (3) and multifocal melanomas (3). Single examples were found of osteoma, osteosarcoma, rhabdomyosarcoma, leiomyoma of the gizzard wall, intestinal adenocarcinoma, renal adenocarcinoma, adrenocortical adenoma and ultimobranchial cyst.

Experimental reproduction of the runting-stunting syndrome of broiler chickens

A model for the reproduction of the runting-stunting syndrome (RSS) of broiler chickens is described. In this model, groups of at least 90 day-old broiler chickens were inoculated (per os) with various tissue homogenates or virus preparations. During the first week post-inoculation, birds were examined for the development of histopathological changes in their intestines. At day 14 post-inoculation, the remaining birds were weighed and tested for elevations in plasma amylase activity and examined for the development of pancreatic atrophy. Bacteria-free intestinal and pancreatic homogenates from chickens of different ages, taken from flocks which developed RSS, regularly induced a lower mean live-weight in treated birds. Of these, only intestinal homogenates prepared from 5-day-old birds induced intestinal lesions, lowered mean live-weight and increased the incidence of both elevated plasma amylase activity and pancreatic atrophy. These changes were more marked in birds exposed to short periods of sub-optimal temperatures during the first week post-inoculation. An ultracentrifuged pellet prepared from this intestinal homogenate, was also found to induce an increased incidence of pancreatic atrophy in treated birds. These studies suggest that the causative agent(s) of RSS is an as yet unidentified virus, and that the effects of this infection are greater in birds subjected to stress, such as sub-optimal temperature exposure, within the first week of hatch.

Isolation of non-cytopathic viruses implicated in the aetiology of nephritis and baby chick nephropathy and serologically related to avian nephritis virus

Three embryo-lethal agents were isolated from broiler chickens having either stunting syndrome or baby chick nephropathy. The agents replicated at low levels in chick kidney cells, but a cytopathic effect was not seen. Their presence was detected by embryo mortalities after yolk sac inoculations. All three agents caused nephritis and growth suppression when inoculated into 1-day-old chicks, and one agent caused increased incidence of baby chick nephropathy. This, and one other agent, were serologically closely related to avian nephritis virus G-4260. Picornavirus-like particles were present in the kidneys of infected birds. The histopathology of baby chick nephropathy was similar to, although more severe than, the nephritis seen in clinically normal birds. The strain of birds used to produce chick kidney cells influenced the ability of G-4260 to form a cytopathic effect and plaques. Strain of bird also influenced the lesions produced on chorio-allantoic membranes after inoculation of G-4260 and the above isolates.

Hepatic coccidiosis (Eimeria sp) in a wild magpie-lark (Grallina cyanoleuca)

Marked distension of the bile ducts was associated with various stages of a protozoan life-cycle which were identified as schizogony and gametogony. The bile ducts contained oocysts some of which were sporulated and had four sporocysts, each with two sporozoites, thus conforming to the genus Eimeria. This is the first report of a coccidian parasite in the bile duct epithelial cells of birds. It is proposed that this coccidia be named Eimeria grallinida ns.

An Outbreak of Highly Pathogenic Avian Influenza in Australia in 1997 Caused by an H7N4 Virus

In November of 1997 an outbreak of highly pathogenic avian influenza occurred near the town of Tamworth, in northern New South Wales, Australia. The viruses isolated from chickens on two commercial chicken farms were identified as H7N4 viruses, with hemagglutinin cleavage site amino acid sequences of RKRKRG and intravenous pathogenicity indices of 2.52 and 2.90, respectively. A virus with an identical nucleotide sequence, but with an intravenous pathogenicity index of 1.30, was also isolated from cloacal swabs collected from asymptomatic emus kept on a third property.

Spironucleosis in Australian king parrots (Alisterus scapularis)

OBJECTIVE

To describe a syndrome of wasting, diarrhoea and mortality in Australian king parrots (Alisterus scapularis).

DESIGN

Field observations and laboratory examinations. Procedure Pathological examinations were performed on 50 Australian king parrots with wasting and diarrhoea. Wet preparations of intestinal contents were examined by light microscopy. Tannins were extracted from acorns (Quercus sp) and tested for toxicity in mice. CLINICAL SIGNS AND EPIDEMIOLOGY: A syndrome of wasting, diarrhoea and mortality was observed in wild juvenile Australian king parrots in eastern Australia from 1984 to 2000. Sporadic cases and outbreaks of disease occurred from May to September in New South Wales, the Australian Capital Territory and Victoria. Outbreaks in the Australian Capital Territory in 1990 and 1991 were associated with parrots congregating to feed on acorns. Most affected birds failed to respond to treatment with dimetridazole and died 1 to 14 days after hospitalisation. Selected cases recovered following treatment with metronidazole.

PATHOLOGY

Affected birds were emaciated, with faecal matting of feathers around the cloaca and yellow-green fluid, foamy intestinal contents. Abundant motile Spironucleus trophozoites were observed in wet preparations of faeces of clinically affected birds and intestinal contents of birds examined within 1 h of death. Protozoa were detected histologically in crypts of Lieberkühn in the intestine in association with exudation of mucus (catarrhal enteritis) or lymphoplasmacytic enteritis. Toxicology Tannin extracts from acorns induced periacinar hepatic necrosis in mice.

CONCLUSION

Wasting, diarrhoea and mortality in wild juvenile Australian king parrots were associated with Spironucleus-like protozoa in the intestine. Acorns were not considered to be the cause of the syndrome.

Bumps on the managed care road: the search for an alternative model to reduce collisions between HMOs, physicians, and patients

Managed care is experiencing political, litigious, and financial bumps on the road. There are various reasons for this bumpy ride: out-of-control costs, prescription drug expense, negative media reports, public revolt at denials of care or limited access to specialists, bad physician relations, patients' rights legislation, dropping health maintenance organization (HMO) stock prices, the ripple effect of the Harvard Pilgrim bankruptcy, and threat of massive litigation against HMOs. Two reasons not often mentioned, but explored in this article, are the orthodox managed care's flawed market model and lack of enough understanding of physician culture and emerging consumer trends to effectively address these two key constituencies.

Listening outside the box: the case of Lyme disease and other tick-borne diseases

To sum up, get out of the box and look at Lyme disease from the point of view of those who believe they suffer from chronic Lyme disease. Meanwhile, spread the word about how to prevent the disease and pass out information about the facts of the disease.

Newspapers foretell health care's future

This article is based on a two-months snapshot (November 1998 to January 1999) of newspaper articles addressing various health care issues. Newspaper contents reflect the changing market share of competing societal concerns. Health care issues, particularly cost and choice, now preoccupy the American people. Health care trends percolate bottom-up through the pages of newspapers, not top-down from Washington, D.C, policymakers, or health care executives. By reviewing these articles, the author provides a big picture view of the prevailing and emerging health care trends. From the new thrust of consumerism and the public backlash against managed care organizations to the demise of HMOs and PPMCs, these observations signify not only the concerns that are bubbling to the surface but also the direction that health care is headed. Consumers are in the driver's seat and physician executives need to provide them with evidence of the value they desire--and understand what they perceive as value.

Impact of managed care on physician organizational behavior

This article examines how physicians act, react, and organize when managed care forces them to consolidate into larger groups and business corporations. Physicians have experimented with ownership by hospitals or business corporations to gain capital, management skills, and information systems. Now they're moving toward physician-owned groups with "outsourcing" of administrative and information system functions. The mood, movement, and momentum of physicians, in short, is toward integrated physician organizations bound together by information that amplifies on their core competencies and capacities to deliver care.

S-100 immunoreactivity in melanomas of two marsupials, a bird, and a reptile

S-100 proteins are abundant in melanocytes of the skin; thus, S-100 immunoreactivity has been used as a diagnostic criterion for melanoma in humans and other placental mammals. We tested cutaneous melanomas of two marsupials, a bird, and a snake for S-100 immunoreactivity, using a polyclonal rabbit antibovine S-100 antibody. The tumor from a Tasmanian Pademelon (Thylogale billaridierii) was composed of large epithelioid cells, most of which had S-100-positive cytoplasm. In general, there were only scattered individual spindle-shaped S-100-positive cells or groups of cells in the primary mass from a Spotted-tailed Quoll (Dasyurus maculatus); S-100 staining was primarily nuclear. Cells comprising the melanomas of the Australian Cormorant (Phalacrocorax carbo) and the Death Adder (Acanthophis antarcticus) were S-100-negative, although peripheral nerve bundles in both were S-100-positive.

Encephalomyocarditis virus infections in an Australian zoo

Fatal encephalomyocarditis virus (EMCV) infections in a ring-tailed lemur (Lemur catta), a squirrel monkey (Saimiri sciureus), three mandrills (Mandrillus sphinx), a chimpanzee (Pan troglodytes), a pygmy hippopotamus (Choeropsis liberiensis), and two Goodfellows tree kangaroos (Dendrolagus goodfellowi) occurred at Taronga Zoo. This is the first description of EMCV in a zoological collection outside of the United States. Regardless of species, the most common clinical presentation was sudden death. The gross pathologic changes were diffuse or focal pallor of the myocardium with occasional marked pulmonary congestion. Necrotizing nonsuppurative myocarditis was consistently present. EMCV was isolated from only one of 54 feral rodents examined. No antibodies to EMCV were detected with a serum neutralization test in 79 stored sera from a wide variety of zoo mammals. Titers of 1:16, 1:16, and 1:4 were recorded for a spider monkey (Aeteles geoffroyi), a lion (Panthera leo), and an orangutan (Pongo pygmaeus), respectively. Of seven mandrills tested in 1988, six had measurable virus titers. Later testing indicated that these titers did not persist, and one mandrill with a titer > 1:128 in 1988 subsequently succumbed to EMCV infection in 1991.

Genetic differences in susceptibility of chicken lines to infection with infectious bursal disease virus

Mortality rates in 11 inbred and partially inbred chicken lines inoculated with a very virulent strain (CS89) of infectious bursal disease virus (IBDV) varied considerably, being highest (almost 80%) in a Brown Leghorn line (BrL). Bursa of Fabricius to body weight ratios were depressed in the survivors in each line, but no differences were observed between lines. However, histological examination of bursae from survivors showed that, although bursal damage occurred in every line, it was most severe in the two lines (BrL and White Leghorn W1) in which the highest mortality was recorded. Experiments with F1 matings between highly susceptible and highly resistant lines showed that resistance was partially dominant and that there were no maternal effects. Experiments using F2 and backcross chicks suggested the involvement of a single gene and indicated no involvement of the MHC. There was considerable variation between lines in IBDV-specific antibody, measured by ELISA, both in the vaccinated parent hens and in the amounts of inherited maternal antibody and its rate of decay in the progeny.

Experimental factors affecting mortality following inoculation of chickens with avian nephritis virus (G-4260)

Groups of approximately 20 one-day-old chickens were inoculated with G-4260, the reference strain of avian nephritis virus (ANV), or saline. Based on mortality rates from severe nephritis in comparable experiments, light Sussex chickens generally were more susceptible than Rhode Island red (RIR) chickens. Mortality was greater in those given broiler starter than those given other feeds, and was greater when light Sussex chickens were given broiler starter feed and cold-stressed at 15 +/- 1 C for 2 hr daily during the first week rather than brooded normally. Inoculation with G-4260 either orally or by intraperitoneal injection produced similar results in RIR chickens. Thirty-three inoculated chickens died of severe nephritis between 4 and 12 days postinoculation, and 24 (73%) of them had visceral urate deposits. Inoculated inbred white leghorn Line 15 chickens with maternal antibody to ANV were brooded normally and given broiler feed: they were susceptible to infection as evidenced by subsequent histological lesions in the kidneys and serology, but mortality was not a feature. There were no deaths from nephritis in inoculated non-inbred white leghorn chickens free of maternal antibody to ANV that were given broiler feed and brooded normally. These results have implications in standardizing experimental conditions for the study of mortality induced by G-4260 and similar viruses.

Some unusual diseases in the birds of Victoria, Australia

The following unusual diseases were diagnosed in birds submitted to the Veterinary Research Institute, Victoria, between 1978 and 1987: the viral diseases beak and feather disease of psittacines, infectious laryngotracheitis in peafowls, a papovavirus-like inclusion body disease in psittacines, and pox; chlamydiosis; the bacterial diseases actinomycosis, listeriosis and mycobacteriosis; the fungal diseases favus, yeast infections and systemic zygomycosis; the protozoan diseases cryptosporidiosis, hexamitiasis, suspected leucocytozoonosis, sarcosporidiosis, toxoplasmosis, trichomoniasis and an unidentified protozoan-like organism which caused pneumonia in ducks; a variety of parasites; the metabolic disorders curled-toe paralysis in pheasant poults, encephalomalacia and parenchymatous goitre; toxicity due to dimetridazole and the ingestion of the leaves of the tobacco tree; and other non-infectious conditions including asphyxiation, burns, cataracts, cerebellar degeneration and atrophy, cystic right oviducts and exertional rhabdomyolysis.

Ascites syndrome in SPF Light Sussex chickens

An ascites syndrome was induced in 17 to 28 per cent of specific pathogen-free (SPF) Light Sussex (LSX) chickens given a low protein (16 per cent crude protein) high calcium (3.5 per cent calcium) layer crumble feed on two separate occasions 6 months apart. Affected chickens had increased right ventricular weight as a proportion of either total heart weight or live-weight at 3 weeks of age, compared with non-affected LSX chickens on the same feed, thus indicating right ventricular hypertrophy. The incidence of ascites was not increased by infection with avian nephritis virus, nor by limited cold-stress during brooding. It was not produced in LSX chickens given other feeds, nor in SPF Rhode Island Red chickens.

A recombinant fowlpox virus that expresses the VP2 antigen of infectious bursal disease virus induces protection against mortality caused by the virus

The coding sequences of VP2 from a virulent strain, 52/70, of infectious bursal disease virus (IBDV) were excised from a cDNA clone and inserted into a fowlpox plasmid insertion vector. The resulting plasmid, pIBD 1, was used to construct a recombinant fowlpox virus, fpIBD 1, which expressed VP 2 as a beta-galactosidase fusion protein. Chickens vaccinated with fpIBD 1 at 1 and 14 days of age, were challenged at 28 days with either IBDV strain 52/70 or the highly virulent strain CS 89. These chickens were protected against mortality, but not against damage to the bursa of Fabricius. The protection achieved by the use of fpIBD 1 shows that VP 2 is a host protective antigen.

Minnesota's fifteen-year romance. Managed care: lessons learned and survival approaches for hospitals and physicians

For the last 15 years, Minnesota has lived with managed care. The Minnesota story is important because it is a singularly unique example of the natural history of managed care in the United States, from the indemnity response to HMOs to PPOs to "open-ended" HMOs to comprehensive managed care.