Potential Pathogens Reported in Species of the Family Viverridae and Their Implications for Human and Animal Health.

The Viverridae is a family of nocturnal carnivores including civets, genets and African linsangs. While a list of known organisms isolated from a species is an essential tool for population management, this review represents the first attempt to collate published reports of organisms isolated from viverrids. A wide range of organisms, including 11 viruses, eight bacterial species, one internal arthropod species, representatives from eight genera of protozoan, 21 genera of nematode, seven genera of cestode, eight genera of trematode and six genera of external arthropod (mites, ticks and louse), have been reported in literature spanning over a century of research. Many of these are capable of infecting multiple hosts, including humans. This is of concern given the anthropogenic factors that bring humans and domestic species into close contact with viverrids, facilitating transmission and spillover of organisms between groups. These factors include trade in viverrids for human consumption, captive management in zoos, rescue centres or on commercial breeding farms, and the increasing overlap of free-ranging viverrid distribution and human settlement.

Capillary channel flow experiments aboard the International Space Station.

In the near-weightless environment of orbiting spacecraft capillary forces dominate interfacial flow phenomena over unearthly large length scales. In current experiments aboard the International Space Station, partially open channels are being investigated to determine critical flow rate-limiting conditions above which the free surface collapses ingesting bubbles. Without the natural passive phase separating qualities of buoyancy, such ingested bubbles can in turn wreak havoc on the fluid transport systems of spacecraft. The flow channels under investigation represent geometric families of conduits with applications to liquid propellant acquisition, thermal fluids circulation, and water processing for life support. Present and near future experiments focus on transient phenomena and conduit asymmetries allowing capillary forces to replace the role of gravity to perform passive phase separations. Terrestrial applications are noted where enhanced transport via direct liquid-gas contact is desired.

Wound healing after mulesing and other options for controlling breech flystrike in Merino lambs: quantitative and semiquantitative analysis of wound healing and wound bed contraction.

BACKGROUND: A two-part study examined wound healing and contraction occurring after mulesing and two alternative methods of preventing breech flystrike in sheep. OBJECTIVE: To quantify wound healing using a scoring system and to assess the contractility of the wound bed of the breech after mulesing, cetrimide-intradermal treatment and application of clips. METHOD: The study group of 30 mulesed, 30 cetrimide-intradermal treated, 30 control and 10 clip-treated sheep were humanely killed at six time points from 3 to 47 days after each treatment. Wound healing post treatment was assessed using a scoring system, and contractility was assessed by the quantification of myofibroblast expression. Statistical analyses allowed comparisons of temporal wound healing and contraction between treatment groups. RESULTS: Mulesing wounds healed faster in the first 11 days, but by 19 days wound healing was similar between the mulesing and cetrimide-intradermal groups. By 32 days, all three treatment groups had similar wound healing scores. There was greater myofibroblast expression in the mulesing group in the first 11 days after treatment, but by 19 days expression was similar in both the mulesing and cetrimide-intradermal groups. The clip group had significantly less myofibroblast expression from 32 days after treatment. CONCLUSION: Wound healing is initially most rapid after mulesing, but there are similar wound healing scores in the mulesing and cetrimide-intradermal treatment groups by 19 days. Both mulesing and the cetrimide-intradermal treatment induce a similar amount of wound bed contraction, with less contraction observed after application of clips.

Histopathological and immunohistochemical evaluation of 53 cases of feline lymphoplasmacytic enteritis and low-grade alimentary lymphoma.

Low-grade alimentary lymphoma (LGAL) is a recently described entity displaying many microscopical features similar to lymphoplasmacytic enteritis (LPE). The aim of this study was to review the histopathological and immunohistochemical features of LPE and LGAL to determine if specific features are useful in distinguishing between these disorders. Fifty-three cases of LPE (n=24) or LGAL (n=29) were recruited retrospectively and prospectively. Of the 24 cases of LPE, 12 were mild, seven were moderate and five were marked in severity. The ileum and jejunum were the most common sites affected for both LGAL and LPE (70-90% of cases). Involvement of the stomach was more common with LPE (29%) than LGAL (7%) (P<0.0001). Twelve cases of LGAL (41%) had evidence of concurrent LPE. Microscopical features significantly associated with LGAL were epitheliotropism, involvement of the muscularis propria and/or serosa, more severe infiltration and more severe changes to the villus and crypt architecture. Plasma cell infiltration within the mucosa, conversely, was a feature of LPE. Twenty-eight of the 29 cases of LGAL were of T-cell phenotype. While many LGAL and most LPE cases had a mixed infiltrate of T and B lymphocytes, LGAL cases had a clear predominance of the T-cell phenotype. Expression of class II molecules of the major histocompatibility complex by enterocytes did not differentiate between LGAL and LPE. In eight of 12 cases of moderate-marked LPE there was disparity in diagnosis by two pathologists regarding differentiation from LGAL, requiring assessment by a third pathologist to reach a consensus diagnosis. This demonstrates the inherent difficulty in differentiating LPE from LGAL on the basis of microscopical and immunohistochemical features alone. Other diagnostic tools such as clonality testing may assist in the definitive diagnosis of such cases.

Assessment of the short-term systemic effect of and acute phase response to mulesing and other options for controlling breech flystrike in Merino lambs.

BACKGROUND: Mulesing is an important method of preventing flystrike of Merino sheep in Australia, but because there are important short-term welfare issues associated with mulesing, alternative methods of removing the skin folds for breech flystrike prevention are being investigated. OBJECTIVE: To examine the short-term systemic effects of mulesing and two proposed alternatives, compared with two control methods, for controlling breech flystrike. METHOD: The five treatment groups comprised 10 lambs each: (1) mulesing, (2) intradermal-cetrimide treatment, (3) clip application, (4) tail docking only and (5) no treatment. Changes in body weight, haematological and biochemical profiles, and concentrations of fibrinogen, haptoglobin and serum amyloid A were measured repeatedly for 29 days post treatment. RESULTS: The mulesing and intradermal-cetrimide groups were the only treatment groups to lose weight during the first week, with greater weight loss in the mulesing group. The mulesing group had the most marked increases in all three acute-phase protein concentrations, closely followed by the intradermal-cetrimide group, with a mild increase observed for the clip group and even less for the tail-docked group. The mulesing group was the only group to develop mild anaemia, transient hyperglycaemia and a persistent decreased albumin : globulin ratio. The neutrophil : lymphocyte ratio was above the upper reference limit for both the mulesing and intradermal-cetrimide groups. CONCLUSION: Mulesing had the greatest systemic effect in terms of the magnitude and duration of increased acute-phase protein concentrations and haematological, biochemical and body weight changes. The clips had a significantly reduced systemic effect compared with mulesing, with the intradermal-cetrimide treatment in between the two. Tail docking had a minimal systemic effect.

Wound healing after mulesing and other options for controlling breech flystrike in Merino lambs: observations on gross and microscopic wound healing.

BACKGROUND: The mulesing procedure is the main procedure used to control breech flystrike of sheep in Australia, but other permanent methods of altering breech conformation are currently being investigated and wound healing is an important component of that comparative assessment. OBJECTIVE: To qualitatively assess the gross and microscopic tissue damage and wound healing that occurs in the immediate post-treatment period after mulesing, intradermal-cetrimide treatment and clip application. METHOD: The study group of 30 mulesed, 30 cetrimide-treated, 30 control and 10 clip-treated sheep were humanely killed at six time points during the 3-47 days post treatment. Treatment sites and wound beds were examined grossly and microscopically. RESULTS: Mulesing wounds healed rapidly in a predictable manner, producing long linear scars on either side of the breech and tail by 32-47 days post treatment. Although the time course for healing post cetrimide-treatment was similar to that for mulesing, complications occurred and included inadequate wound healing because of persistence of adherent necrotic tissue, poor skin tightening around the tail, and patchy or deep penetration of the cetrimide resulting in necrosis of adjacent skin and deeper structures. The clips resulted in skin tightening around the ventrolateral breech and tail, although the formation of skin tags and clip slippage were of concern in some sheep. CONCLUSION: Wounds healed rapidly after mulesing with minimal complications. The intradermal-cetrimide treatment appeared to produce imperfect and sometimes delayed wound healing compared with mulesing. The clips resulted in comparable wound healing to mulesing, but further field trials are required to assess their effectiveness in flystrike prevention.

Histopathological examination of the pancreas of the Koala (Phascolarctos cinereus).

This retrospective study, which was based on koala pancreatic specimens taken 2, 24, 48 and 72h after death, showed that the degree of autolysis did not necessarily exclude histopathological examination. Disorders not previously reported in the pancreas of koalas included the following: inflammation and necrosis; atrophy and fibrosis of exocrine pancreatic tissue; lymphosarcoma; pancreatic heterotopy; and ductal adenocarcinoma.

Haematological, biochemical and selected acute phase protein reference intervals for weaned female Merino lambs.

BACKGROUND: Merino lambs are currently the subject of much research into the welfare aspects of mulesing and mulesing alternatives. OBJECTIVE: Obtain haematology, biochemistry and acute phase protein reference intervals using modern methodologies for female Merino lambs. METHOD: Blood was collected from 50, weaned, 9- to 16-week-old, female Merino lambs. Haematology and biochemistry panels were performed using routine automated methods. The acute phase proteins, fibrinogen, serum amyloid A and haptoglobin, were also measured using commercially available techniques. The reference intervals were determined to be the central 95% of results. RESULTS: Differences in the concentrations for some analytes were seen when compared with reported studies in sheep, but may be explained by the use of sheep of a different signalment, as well as different methodologies for analyte measurement. Overall, most analytes gave similar values to those previously reported in other studies. Notable exceptions were alkaline phosphatase, phosphate and globulins, for which the different results were often attributed to the younger age of the sheep in the present study, and platelets and creatine kinase, for which the elevated levels may have been a result of stress and muscle exertion associated with blood collection and husbandry practices. CONCLUSION: Established haematological, biochemical and acute phase protein reference intervals are necessary for the investigation of the systemic impact of mulesing and mulesing alternatives and for the investigation of systemic diseases affecting weaned, 9- to 16-week-old, female Merino lambs in general.

Erythrocytic pyruvate kinase deficiency and AB blood types in Australian Abyssinian and Somali cats.

OBJECTIVE: To determine the frequency of the mutant pyruvate kinase (PK) allele, haematological parameters and AB blood types of Abyssinian and Somali cats in Australia. DESIGN: Complete blood cell and reticulocyte counts, DNA PK mutation testing and blood typing were performed in all cats. RESULTS: A total of 60 cats (36 Abyssinians, 24 Somalis) were included (37 females, 23 males). For the mutant PK allele, three female Somalis were homozygous (affected, 5%), 17 cats were heterozygous (carrier, 28%) and 40 cats tested negative (normal, 67%). Pedigree analysis revealed common ancestry of affected and many carrier cats. Of affected cats, two had regenerative anaemias and all had reticulocytosis (range 64-390 x 10(9)/L; P < 0.001 compared with normal or carrier cats). The only consistent historical sign was lethargy. One affected cat was euthanased 18 months after testing, because of anaemia, neutropenia, anorexia and weight loss. The mutant allele frequency was 0.19 overall (0.29 in Somalis, 0.13 in Abyssinians). All cats had blood type A. The commercial blood typing card method incorrectly identified 12 cats as having type AB blood. CONCLUSIONS: The frequency of the mutant PK allele is high in Australia. Screening for PK deficiency is indicated before mating and in individual cats of these breeds, even in the absence of anaemia and especially when there is reticulocytosis. Although all cats in the present study had blood type A, blood type B is common in these breeds worldwide. Retyping of any AB typed cats by a laboratory technique is recommended.

Detection of Anaplasma platys and Babesia canis vogeli and their impact on platelet numbers in free-roaming dogs associated with remote Aboriginal communities in Australia.

OBJECTIVE: To detect Anaplasma platys and Babesia canis vogeli infection, using polymerase chain reaction (PCR)-based assays, in free-roaming dogs associated with eight Aboriginal communities in remote areas of Australia and to determine the impact of infection through the assessment of platelet numbers. PROCEDURES: Blood samples from 215 dogs were screened by PCR for A platys and B canis vogeli using established genus-specific DNA primers for the 16S and 18S rRNA genes respectively. Both A platys DNA and B canis vogeli DNA were confirmed from the screening PCR either by sequencing or by the use of species-specific primers. Peripheral blood films from 92 of the 215 dogs were used to estimate platelet numbers through an indirect method. RESULTS: Of 215 dogs, 69 (32%) were positive for A platys, 22 (10%) for B canis vogeli and 24 (11%) for both. The two organisms were detected singularly and as coinfection in all communities. For the 92 dogs in which peripheral blood films were examined, the mean estimated platelet counts for the non-infected dogs was 318 x 10(9)/L, those infected with A platys alone was 256 x 10(9)/L, those with B canis vogeli alone was 276 x 10(9)/L and those infected with both parasites was 169 x 10(9)/L. In young dogs, infection produced significantly decreased mean platelet counts when compared to uninfected dogs. Thrombocytopenia (< 200 x 10(9)/L) was detected in 18 (51%) dogs infected with A platys alone, 3 (33%) dogs infected with B canis vogeli alone, 13 (72%) dogs coinfected, and 8 (27%) uninfected dogs. CONCLUSIONS: A platys and B canis vogeli infection, either singularly or together, was widespread in free roaming dogs associated with remote Aboriginal communities in the Northern Territory and north-western New South Wales. Moreover, both A platys and B canis vogeli infections were associated with a reduction in mean platelet numbers in dog populations, particularly in young dogs. The fact that 51% of dogs infected with A platys alone and 72% dogs coinfected were thrombocytopenic compared to 27% of uninfected dogs suggests that the organism alone or in combination with B canis vogeli has the potential to cause thrombocytopenia and perhaps contribute to a clinical bleeding disorder in infected dogs.

Immuno-histochemical demonstration of the role of chlamydiaceae in renal, uterine and Salpingeal disease of the koala, and demonstration of chlamydiaceae in novel sites.

Numerous bacteria, including Chlamydophila pecorum and Chlamydophila pneumoniae, are known to occur in diseased sites in koalas. In the present study the significance of such organisms was investigated by demonstrating their distribution in situ, in tissues collected opportunistically from wild koalas. Chlamydiaceae were demonstrated in epithelial cells and macrophages in association with pyogranulomatous pyelonephritis (8/11 kidneys), focal interstitial nephritis (3/21), and active inflammation and fibrosis of the entire upper female reproductive tract (10/10). In one case of pyelonephritis, Gram-positive cocci were also demonstrated in association with Chlamydiaceae and, in another, haematogenous filamentous bacteria appeared to be the sole aetiological agent. Three cases of chlamydial metritis were also superficially co-infected by a mixture of other bacteria. Chlamydiaceae were also demonstrated in pulmonary alveolar macrophages and epithelial cells in association with pneumonitis, and in hepatic and splenic macrophages in one koala. The study illustrated the prominent role of Chlamydiaceae in renal disease and disease of the uterus, uterine tube and ovarian bursa, with implications for pathogenesis and therapy. In addition, macrophages appeared to be a potential site of latent persistence from which systemic spread of infection might occur.

Cryptococcus neoformans var. gattii in the koala (Phascolarctos cinereus): a review of 43 cases of cryptococcosis.

Details of 11 previously reported cases and 32 new cases of cryptococcosis in captive and wild koalas were analysed. Cryptococcus neoformans var. gattii accounted for all 29 cases in which varietal status was determined. No age or sex predisposition was observed. The respiratory tract was the primary focus of disease in 77% of cases. Although the lower respiratory tract was affected most commonly (60% of cases), 30% of cases had upper respiratory tract lesions and 14% had both. Dissemination was common, especially to the central nervous system (37% cases). Local extension to surrounding tissues was a feature of upper respiratory tract disease. Other tissues showing cryptococcal invasion included lymph nodes (19%), gastrointestinal tract (12%), kidneys (12%), spleen (9%) and skin (7%). Only three cases (7%) had no respiratory tract or central nervous system involvement, two cases of primary skin inoculation and one case of primary lymphadenopathy. Late presentation was a likely factor in the high proportion of cases with disseminated disease (40%). The proportion of koala cases with involvement of the central nervous system, lower respiratory tract and skin, parallels what has been reported for immunocompetent people. Cryptococcosis in the koala appears to be an excellent naturally occurring model for examination of the cryptococcal host-parasite relationship in all species.

Evaluation of d,l-ethionine as a mechanism for pancreatic islet regeneration in dogs.

OBJECTIVE: To determine whether induction of pancreatic necrosis and islet proliferation by d,l-ethionine has potential for treating dogs with beta-cell insufficiency. DESIGN: Eighteen mixed breed dogs of both sexes were given d,l-ethionine at 100 mg/kg three times weekly for 2 weeks; 6 dogs were euthanased at 2, 14 and 28 d after the last dose. METHODS: Clinical signs during administration and recovery were assessed. Routine biochemical analyses were performed before each ethionine dose and then once weekly. Faecal samples were examined weekly for malassimilated nutrients and blood. Blood coagulation screening tests (OSPT and APTT) were determined on four dogs after ethionine administration. Intravenous glucose tolerance tests were conducted before the first and after the last ethionine dose and then fortnightly. All dogs were necropsied and pancreas, liver, kidney and jejunum were examined microscopically. RESULTS: During ethionine administration all animals displayed vomiting, inappetence, diarrhoea (often with blood), weight loss and depression. Three dogs were euthanased prematurely due to severe illness, but those allowed to recover were eating and brighter 7 d after cessation of ethionine administration. Serum concentrations of TLI, amylase and lipase increased initially, then decreased, during administration but retumed to normal during recovery. Concentrations of ALT, ALP, unconjugated and conjugated bilirubin increased during administration then decreased slowly. Histological examination revealed hepatic lipidosis and necrosis, but no renal or jejunal lesions. In most dogs, faecal examination demonstrated increased undigested starch and muscle, as well as increased digested and undigested fat, during ethionine administration or early during the recovery period, suggesting transient malassimilation. APTT was unchanged but OSPT was prolonged in all dogs. There was no impairment of insulin secretion or glucose intolerance and C-peptide concentrations were unaffected. Immediately after ethionine administration there was delayed insulin degradation and by day 43 there was evidence of increased insulin sensitivity. CONCLUSION: d,l-ethionine administration in dogs appeared not to interfere with insulin secretion, but caused clinical signs and laboratory changes indicative of pancreatic exocrine necrosis, severe hepatobiliary disease and transient malassimilation. Pancreatic and hepatic dysfunction was severe but clinical recovery occurred after ethionine administration ceased. The severe side-effects observed with d,l-ethionine should preclude its potential use for treating diabetes mellitus in dogs.

Cryptococcus neoformans in the koala (Phascolarctos cinereus): colonization by C n. var. gattii and investigation of environmental sources.

This study is the one in a series looking at the relationship among Cryptococcus neoformans var. gattii, koalas and the environment. The koala was used as a natural biological sampler in an attempt to understand the dynamics of C. neoformans var. gattii in Australian environments. Evidence of asymptomatic nasal and skin colonization for extended periods by large numbers of C. n. var. gattii was obtained and geographical factors assessed. The key finding was the ability of koalas to amplify numbers of C. n. var. gattii in certain environments. Koalas were not found to be obligatory for the survival of the organism in all environments. Geographical factors alone could not explain differing rates of nasal and skin colonization in koalas in different environments. A strong association between healthy koalas and C. n. var. gattii was confirmed and C n. var. gattii was isolated from novel sources, including the turpentine gum tree (Syncarpia glomulifera), tallowwood (Eucalyptus microcorys) and flooded gum (E. grandis). It seems likely that as yet undiscovered environmental sources of C. n. var. gattii exist in eastern Australia. Further investigation of host, environmental and organism factors integral to the hostpathogen relationship will assist an understanding of the progression from colonization to tissue invasion and cryptococcosis in all species.

Cryptococcus neoformans var. gattii in the koala (Phascolarctos cinereus): serological evidence for subclinical cryptococcosis.

Cryptococcus neoformans var. gattii has been shown to have a strong association with eucalypts frequently used by koalas and, not surprisingly, it has been shown to colonize the nasal cavities of koalas. The progression from nasal colonization to tissue invasion is critical to understanding the pathogenesis of cryptococcosis in this species and provides a model for pathogenesis of cryptococcosis in other species. Cryptococcal antigenaemia was detected in twenty-eight healthy koalas from three different regions. This was interpreted as representing limited subclinical disease. One koala developed cryptococcal pneumonia 6 months after leaving the study, whereas another developed cryptococcal meningoencephalitis during the course of the study. Opportunistic necropsies on ten antigen-positive koalas resulted in discovery of small cryptococcal lesions in two (paranasal sinus and lung, respectively). Our data suggest that cryptococcal antigenaemia occurs commonly in koalas, especially in areas with a high environmental presence of C n. var. gattii. Subclinical disease appears most likely to manifest as a small focal lesion in the respiratory tract. Possible outcomes include elimination by an effective immune response, quiescence with possibility of later re-activation or direct progression to overt disease. Symptomatic and subclinical cases showed differences in levels of antigenaemia. The data presented have significant implications for koalas in captivity.