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121.
Extract

Sir:- In June 1982, possums (Trichosurus vulpecula) from the Waitahuna forest area near Lawrence in Central Otago were examined for endoparasites (181 possums) and ectoparasites (125 possums). The alimentary tract was separated into stomach, small intestine and large intestine. These sections were washed thoroughly through a 60 mesh sieve and total parasite counts and identification were carried out. The fur from the base of the forelegs along the back and around the base of the tail was digested in 20% KOH and the ectoparasites were recovered. There was no evidence of pathogenicity ascribable to the parasites found. A summary of results is presented in Table I.  相似文献   
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123.
Rapid ?ōhi?a Death (ROD) is a fungal disease of ?ōhi?a lehua (Myrtaceae: Metrosideros polymorpha) caused by Ceratocystis lukuohia and C. huliohia. ROD is the aetiological agent of widespread mortality of this important tree on Hawai?i Island, but its epidemiology remains unclear. We investigated the prevalence and viability of C. lukuohia in ambrosia beetle frass in ROD‐affected ?ōhi?a trees. A total of 200 frass traps were placed onto C. lukuohia‐infected ?ōhi?a at four locations on the east side of Hawai?i Island. Frass was collected and screened for the presence of C. lukuohia DNA using a diagnostic qPCR assay. In addition, frass samples were screened for viability by carrot baiting. All trapped beetles were of the genus Xyleborus, with the majority being the non‐native X. ferrugineus. Of the frass samples tested, 62% contained C. lukuohia DNA and 17% of carrot baits were positive for the fungus. These results indicate that ambrosia beetle frass releases C. lukuohia into the environment. We discuss the potential role infested frass could play in the ROD pathosystem.  相似文献   
124.
Current theory expects that fungi, on the one hand, are spatially ubiquitous but, on the other, are more susceptible than bacteria to disturbance such as land use change due to dispersal limitations. This study examined the relative importance of location and land use effects in determining soil fungal community composition in south-eastern Australia. We use terminal restriction fragment length polymorphism (T-RFLP; primer pair ITS1-F–ITS4) and multivariate statistical methods (NMDS ordinations, ANOSIM tests) to compare relative similarities of soil fungal communities from nine sites encompassing three locations (ca 50–200 km apart) and four land uses (native eucalypt forest, Pinus radiata plantation, Eucalyptus globulus plantation, and unimproved pasture). Location effects were generally weak (e.g. ANOSIM test statistic R  0.49) and were, in part, attributed to minor differences in soil texture. By contrast, we found clear and consistent evidence of land use effects on soil fungal community composition (R  0.95). That is, soils from sites of the same land use grouped together in NMDS ordinations of fungal composition despite geographic separations of up to ca 175 km (native eucalypt forests) and 215 km (P. radiata plantations). In addition, different land uses from the same location were clearly separate in NMDS ordinations, despite, in one case, being just 180 m apart and having similar land use histories (i.e. P. radiata versus E. globulus plantation both established on pasture in the previous decade). Given negligible management of all sites beyond the early establishment phase, we attribute much of the land use effects to changes in dominant plant species based on consistent evidence elsewhere of strong specificity in pine and eucalypt mycorrhizal associations. In addition, weak to moderate correlations between soil fungal community composition and soil chemical variables (e.g. Spearman rank correlation coefficients for individual variables of 0.08–0.32), indicated a minor contributing role of vegetation-mediated changes in litter and soil chemistry. Our data provide evidence of considerable plasticity in soil fungal community composition over time spans as short as 6–11 years. This suggests that – at least within geographic zones characterised by more-or-less contiguous forest cover – soil fungal community composition depends most on availability of suitable habitat because dispersal propagules are readily available for colonisation after land use change.  相似文献   
125.
We have determined the first complete genome sequence and capsid gene sequences of feline calicivirus (FCV) isolates from the UK and Australia. These were compared with other previously published sequences. The viruses used in the comparisons were isolated between 1957 and 1995 from various geographical locations and obtained from cats showing a range of clinical signs. Despite these diverse origins, comparisons between all strains showed a similar degree of sequence variation within both ORF1 (non-structural polyprotein) and ORF2 (major capsid protein) (amino acid distances of 7.7-13.0% and 8.8-18.6%, respectively). In contrast, ORF3 (putative minor structural protein) sequences indicated a more heterogenous distribution of FCV relatedness (amino acid distances of 1.9-17.9%). Phylogenetic analysis suggested that, unlike some other caliciviruses, FCV isolates within the current data set fall into one diverse genogroup. Within this group, there was an overall lack of geographic or temporal clustering which may be related to the epidemiology of FCV infection in cats. Analysis of regions of variability in the genome has shown that, as well as the previously identified variable regions in ORF2, similar domains exist within ORFs 1 and 3 also, although to a lesser extent. In ORF1, these variable domains largely fall between the putative non-structural protein functional domains.  相似文献   
126.
A four-month-old German Shepherd Dog (GSD) was admitted with bilateral non-weight bearing hindlimb lameness and pyrexia. A diagnosis of bilateral distal femoral fractures secondary to metaphyseal osteopathy was made on the basis of clinical signs, radiography and biopsy. The dog returned to normal function following conservative management. As far as the authors are aware there are no previous reports of pathological fractures secondary to this condition.  相似文献   
127.
A progressive wart-like syndrome in both captive and wild populations of the Western barred bandicoot (WBB) is hindering conservation efforts to prevent the extinction of this endangered marsupial. In this study, 42 WBBs exhibiting the papillomatosis and carcinomatosis syndrome were examined. The disease was characterized by multicentric proliferative lesions involving cutaneous and mucosal surfaces, which were seen clinically to increase in size with time. Grossly and histologically the smaller skin lesions resembled papillomas, whereas the larger lesions were most commonly observed to be squamous cell carcinomas. Large amphophilic intranuclear inclusion bodies were observed in hyperplastic conjunctival lesions of 8 WBBs under light microscopy. Conjunctival lesions from 2 WBBs examined using transmission electron microscopy contained a crystalline array of spherical electron-dense particles of 45-nm diameter, within the nucleus of conjunctival epithelial cells, consistent with a papillomavirus or polyomavirus. Conjunctival samples from 3 bandicoots that contained intranuclear inclusion bodies also demonstrated a positive immunohistochemical reaction after indirect immunohistochemistry for papillomavirus structural antigens. Ultrastructural and/or immunohistochemical evidence of an etiologic agent was not identified in the nonconjunctival lesions examined. Here we describe the gross, histopathologic, ultrastructural, and immunohistochemical findings of a papillomatosis and carcinomatosis syndrome recently identified in the WBB.  相似文献   
128.
Fossil cephalopods are frequently encrusted by epibionts; however, determining whether encrustation occurred prior to or post‐mortem to the host, and whether the final environment of deposition corresponds to the habitat of encrustation is complex. The present paper describes cirripede epibionts, their calcareous bases and their attachment scars on 6 post‐mortem shells of Nautilus macromphalus, collected from deep water off New Caledonia. The cirripedes have left both cemented calcareous bases of Hexelasma and scars associated with bioerosion and discoloration produced by verrucomorph barnacles. Live cirripedes included a Metaverruca recta, with articulated opercular plates and organic tissue (on a shell that had been exposed on the sea floor for at least 150 years), and specimens of Hexelasma velutinum, one of which was partly attached to an internal surface of a shell. The disposition of verrucomorphs indicates that most Nautilus shells were colonized post‐mortem rather than during a floating stage. However, as cirripedes are known to have colonized living Nautilus, some Hexelasma, preserved only as calcareous eroded bases, may represent specimens that settled on a living Nautilus. The degree of bioerosion and discoloration induced by verrucomorph barnacles varies according to the surface preservation of Nautilus shells, with deeper and discolored traces preserved on old and degraded shells. Traces made by verrucomorphs described here are ellipsoidal and a new ichnotaxon, Anellusichnus ellipticus, is proposed to accommodate them. Importantly, verrucomorphs and other cirripede taxa with membranous bases that were attached to pristine shells may not leave any substantial scars, and, thus, will be difficult to detect in the fossil record.  相似文献   
129.
The western barred bandicoot, Perameles bougainville, is an endangered Australian marsupial species. Routine histology of liver samples collected at necropsy from 19 of 20 (95%) western barred bandicoots revealed the sporadic to common occurrence of abnormal hepatocyte nuclei characterized by margination of chromatin and concomitant central pallor. Some abnormal hepatocyte nuclei were mildly to markedly enlarged and irregularly shaped. Periodic acid-Schiff reagent stained 131 of 142 (92%) of these abnormal hepatocyte nuclei. Positive staining was completely eliminated by diastase pretreatment. Transmission electron microscopy revealed that abnormal hepatocyte nuclei with marginated chromatin did not contain viral particles. Rather, glycogen beta-particles and alpha-rosettes were identified within some abnormal hepatocyte nuclei. Glycogen intranuclear inclusions were an incidental finding in western barred bandicoot hepatocytes.  相似文献   
130.
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