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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. To examine the short-term systemic effects of mulesing and two proposed alternatives, compared with two control methods, for controlling breech flystrike. 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. 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. 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. [ABSTRACT FROM AUTHOR]

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. 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. 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. 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. 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. [ABSTRACT FROM AUTHOR]

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 × 109/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. [ABSTRACT FROM AUTHOR]

Leopard seal, Hydrurga leptonyx, and Weddell seal, Leptonychotes weddellii, occupy an upper trophic level within the Antarctic ecosystem and are useful indicator species in the Southern Ocean of trace element concentrations. Reference values for the concentration of 19 trace elements were determined in the serum and hair of leopard and Weddell seals sampled in Eastern Antarctica. These reference values can be used as 'baseline' levels for monitoring trace element concentrations in these species. Greater trace element concentrations were determined in hair compared to serum, indicating different time scales of trace element accumulation in these samples. For the majority of trace elements, except for Se in the leopard seal samples and Cr in the Weddell seal samples, significant regression relationships for trace element concentrations in hair and serum were not elucidated. Significant differences were determined in the concentrations of seven out of 15 elements with hair type, moult and new, in the leopard seal; concentrations in moult hair were determined to be greater than in new hair for all elements except Zn. Hair analysis was determined to be useful for monitoring exposure to trace elements and when collected off the ice from moulting seals, hair can be employed as a non-invasive sample for trace element analysis in leopard and Weddell seals.

Blood protein analysis including total serum protein and albumin by chemical methods, fibrinogen estimation and serum protein electrophoresis (SPE) was performed on the leopard seal, Hydrurga leptonyx. The most commonly observed SPE pattern was eight fractions designated albumin, alpha(1a), alpha(1b), alpha(2a), alpha(2b), beta(1), beta(2) and gamma-globulin. Significantly higher total serum protein and albumin concentrations, as determined by chemical methods, and significantly higher alpha(2)-globulin concentrations, determined by SPE, were seen in free-ranging male seals compared to females, whilst significantly higher beta-globulin concentrations were seen in female seals. Season of sampling influenced fibrinogen and beta(2)-globulin concentrations, whereas there were no significant differences in any protein concentrations with moult status. Qualitative comparison of SPE traces of leopard seals in Antarctica with "sick" individuals in NSW, Australia revealed obvious differences, as did quantitative comparison of protein concentrations where differences in alpha(1), alpha(2), beta(1), beta(2), and gamma-globulin concentrations were seen. These findings suggest that SPE is a useful tool for investigating serum proteins in the leopard seal, with applications for the investigation of "sick" individuals and the assessment of variation in homeostasis. This technique could also be used to identify the presence of environmental stressors, subclinical disease and physiological variation within specific seal populations.

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.

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.

Objective: To describe, for the first time, haematological and serum biochemical findings in cases of lymphosarcoma in Australian cats., Design: A prospective multi-institutional study., Procedure: Of 118 affected cats presented to the authors over a 18-month period, 97 were evaluated haematologically and 87 biochemically. Haematological analysis usually included determination of packed cell volume, haemoglobin concentration, red blood cell and leukocyte counts, differential leukcocyte count, reticulocyte count and examination of buffycoat smears for neoplastic cells. Serum biochemical analysis was done primarily with a discrete analyser and included a panel of commonly used analytes., Results: Nonregenerative anaemia was present in 54% (52/97) of cats. Neutrophilia, present in 65% (59/91) of cats, was commonly associated with lymphocytopaenia, eosinopaenia and monocytosis. Of the 13 cats with a secondary leukaemic manifestation, only five had distinct lymphocytosis. Serum biochemical abnormalities either were nonspecific, such as hypoglycaemia in 37% (32/87) of cats, or related to specific tissue involvement, such as hypoalbuminaemia in 76% (31/41) of cats with alimentary involvement and azotaemia in 60% (15/25) of cats with renal involvement., Conclusion: It was shown for the first time that haematological and serum biochemical findings are of limited value in diagnosing lymphosarcoma in Australian cats, except if they are leukaemic. Although clinical pathological changes were common, they were nonspecific or related to specific tissue involvement. Their value in assessing response to therapy needs to be examined further. Patient characteristics such as age, breed and sex also had limited effect on laboratory findings and those observed were of little consequence. Additionally, histological and immunophenotypical variations in tumour type had little effect on laboratory findings.

This report presents information on the range of diseases and lesions that occurred in sections of livers of macropods held in the Non-Domestic Animal Registry at Taronga Zoo. Of 142 affected livers, 52 were due to parasites, 24 to bacteria, nine to Macropod Herpesvirus, four to fungal agents and ten to tumours. In addition, 17 livers had acute degenerative or necrotic lesions, 22 were affected by fibrosis or other chronic lesions and four had miscellaneous degenerative lesions. Common parasitic diseases included toxoplasmosis, coccidial cholangitis, cestode cholangitis (Progamotaenia sp.), fascioliasis and capillarial hepatitis. Bacterial diseases were varied but lesions due to anaerobic bacteria or Mycobacteria spp. were most common. Many of the acute degenerative lesions were associated with cardio-respiratory disease. Chronic lesions were often of unknown origin, although it was speculated that parasitic and bacterial organisms contributed to the aetiology. There were four primary and six metastatic tumours.

Tyzzer's disease (Bacillus piliformis infection) was diagnosed in nine marsupials (six possums, a koala, a wombat and a dasyurid). All but two of the possums were captive. Five of the seven marsupials, for which ages were recorded, were juvenile. Affected marsupials were either found dead or were showing non-specific illness for up to two days before death. Affected livers and hearts showed gross haemorrhage and scattered areas of white discolouration. Microscopically, areas of coagulative necrosis were often associated with neutrophilic infiltrates. Intracellular, slender, faintly basophilic rods were occasionally detected in HE-stained sections. Rods were shown by silver staining techniques to be associated with the lesions in all affected animals. These rods showed a beaded appearance when stained with methenamine silver and were consistently in packets within cells, on the peripheries of lesions and scattered sparsely and irregularly within the central necrotic regions.

This report describes toxoplasmosis lesions in Australian marsupials. Clinical signs, necropsy findings and histopathological changes are summarized for 43 macropods, two common wombats, two koalas, six possums, 15 dasyurids, two numbats, eight bandicoots and one bilby. Animals either died suddenly without clinical signs or exhibited signs associated with respiratory, neurological or enteric disease. At necropsy, many marsupials had no visible lesions. Where present, common necropsy findings included pulmonary congestion, oedema and consolidation, adrenal enlargement and reddening, haemorrhage and ulceration of stomach and small intestine, and lymphadenomegaly and splenomegaly. Microscopically, affected lungs showed interstitial pneumonia and macrophage accumulation. Myocardial, skeletal and smooth muscle necrosis and neutrophilic inflammation were common. Organs had focal necrosis and/or fibrosis and lymphoid infiltrates. Toxoplasma gondii tissue cysts were common in muscle and nervous tissue. Free tachyzoites were commonly present in areas of necrosis. Selected sections from four macropods, two koalas, two dasyurids, one wombat and one possum stained specifically with avidin-biotin complex and anti-Toxoplasma gondii serum.

This report catalogues all spontaneous proliferations in dasyurids and bandicoots held by the Comparative Pathology Registry at Taronga Zoo. Proliferative lesions were present in 70 dasyurids and three bandicoots. Hyperplastic or benign neoplastic masses in adrenals and livers were common in dasyurids. In addition, previously misdiagnosed splenic haematopoietic hyperplasia was common. A variety of mammary proliferations was present in dasyurids. Dasyurids often had multiple proliferative lesions. Lymphoid neoplasia was common, especially in the smaller dasyurids. No obvious aetiological factors have been identified in any of the tumour conditions in dasyurids although there is some evidence to suggest a genetic predisposition to lymphosarcoma in the fat-tailed antechinus.

This report catalogues all spontaneous proliferations in macropods, koalas, wombats, and possums and gliders held by the Comparative Pathology Registry at Taronga Zoo. Proliferative lesions were present in 14 macropods, 26 koalas, two wombats and 22 possums and gliders. Most neoplasms recorded in macropods were singular and many were found incidentally. Lymphoid neoplasia, cranio-facial tumours and apparent mesotheliomas were common in koalas. Hyperplastic or benign neoplastic masses in adrenals and livers were common in possums. In addition, previously misdiagnosed splenic haematopoietic hyperplasia was common in these animals. Mammary proliferations were present in macropods and gliders. No obvious aetiological factors have been identified in any of the tumour conditions, although there is some evidence to suggest a viral involvement in lymphosarcoma in koalas.

Blood samples were collected from 24 immature male, 55 immature female and 99 mature female water buffalo kept at an experimental farm in the Northern Territory. Haematological analysis was performed on blood collected in dipotassium--ethylene diamine tetra acetic acid while biochemical analysis was performed on serum and plasma (for glucose) samples. Haematological values of mature buffalo were similar to those recorded for swamp buffalo in Malaysia. Blood cell appearances were similar to those reported for adult Indian river buffalo though values recorded for red cell components were higher. Statistical analysis revealed no significant differences between immature male and female buffalo. Red cell components, eosinophils, total plasma and serum proteins, albumin, gamma globulins, inorganic phosphate and the enzyme gamma-glutamyl transferase were significantly higher for mature female buffalo when compared to immature females. Reasons for the differences were not fully determined but the effect of age and nutritional status in combination with a variable period of domestication were considered.

Blood smears from 54 platypuses in southeastern Australia were examined by light microscopy. Protozoa were found in erythrocytes in 53 platypuses; all infections were sparse. A few parasites were found in leukocytes. Intraerythrocytic forms examined by electron microscopy contained vacuoles, micronemes, rhoptries and cytostomes with double unit membranes. Merozoites were identified in leukocytes. The parasites were identified as Theileria ornithorhynchi Mackerras, 1959.

Haematological and biochemical investigations were performed on 14 koalas with uncomplicated cystitis, 8 with complicated cystitis, 8 with conjunctivitis, 8 with lymphosarcoma, and 14 with miscellaneous diseases. Changes were limited and inconsistent in individual koalas with uncomplicated cystitis and conjunctivitis. In contrast, individual koalas with complicated cystitis were more likely to have anaemia, leukocytosis due to neutrophilia, hypoproteinaemia due to hypoalbuminaemia, and azotaemia due to elevated urea concentration. Although these changes were non-specific they did allow assessment of prognosis for survival and response to treatment. Koalas with lymphosarcoma were invariably anaemic, leukaemic, azotaemic and hypoalbuminaemic. Elevated enzymes (aspartate transaminase [AST]. lactate dehydrogenase [LD] and gamma glutamyl transferase [GGT]) were more common in koalas with lymphosarcoma. Koalas affected by miscellaneous conditions showed variable changes but once again anaemia, leukocytosis, azotaemia, elevated AST and LD, and hypoalbuminaemia were not uncommon. On the basis of these findings a minimal profile is suggested for the investigation of sick koalas and would include haematocrit, total and differential leukocyte counts, urea, total protein and albumin concentrations and AST, GGT and LD activities.