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71.
Amy Robbins Joanne Loader Deidre de Villiers Hawthorne L. Beyer Jonathan Hanger 《Australian veterinary journal》2019,97(9):351-356
Koalas (Phascolarctos cinereus) are experiencing significant declines across the northern part of their range. However, unbiased, population‐level estimates of mortality are rarely reported, as it's difficult to quantify causes of mortality robustly in this cryptic species. We aimed to determine the relative importance of carpet python (Morelia spilota) predation in a free‐living koala population and describe the characteristic pathological findings during necropsy. In total, 503 koalas were captured, underwent veterinary examination and telemetric tagging, and were monitored after release over a four‐year period. Mortalities were detected when activity data reported by K‐Tracker® biotelemetry collars indicated low or zero activity, or during routine field monitoring events. Experienced koala veterinarians performed thorough, standardised necropsy examinations on retrieved carcasses to determine causes of death. The three, sometimes subtle, cardinal signs used to definitively diagnose carpet python‐caused deaths of koalas were a U‐shaped primary bite site, slicking of the fur by python saliva (particularly around the face), and diffuse, uniform pulmonary congestion. We found that carpet pythons were important predators of koalas, second only to wild dogs (dingoes and dingo hybrids (Canis familiaris dingo)), accounting for 11.6% of predation deaths and 7.2% of total deaths. Less than half (38%) of the koalas killed by carpet pythons were ingested. Though carpet pythons are known predators of koalas, their relative importance as a cause of mortality hasn't previously been recognised. Population viability analyses and conservation management plans benefit from robust cause‐of‐death data collected during longitudinal monitoring studies, requiring telemetry methods that facilitate rapid detection of mortalities. 相似文献
72.
Milan Milovancev Joanne L. Tuohy Katy L. Townsend Veronica L. Irvin 《Veterinary and comparative oncology》2019,17(3):354-364
The present peer‐reviewed veterinary literature contains conflicting information regarding the impact of surgical margin completeness on risk of local tumour recurrence in canine soft tissue sarcoma (STS). This systematic review and meta‐analysis was designed to answer the clinical question: “Does obtaining microscopically tumour‐free surgical margins reduce risk for local tumour recurrence in canine cutaneous and subcutaneous STS?” A total of 486 citations were screened, 66 of which underwent full‐text evaluation, with 10 studies representing 278 STS excisions ultimately included. Cumulatively, 16/164 (9.8%) of completely excised and 38/114 (33.3%) of incompletely excised STS recurred. Overall relative risk of 0.396 (95% confidence interval = 0.248‐0.632) was calculated for local recurrence in STS excised with complete margins as compared to STS excised with incomplete margins. Risk of bias was judged to be low for all studies in terms of selection bias and detection bias but high for all studies in terms of performance bias and exclusion bias. The results of the present meta‐analysis, coupled with the results of individual previous studies, strongly suggest that microscopically complete surgical margins confer a significantly reduced risk for local tumour recurrence in canine STS. Future studies ideally should adhere to standardized conducting and reporting guidelines to reduce systematic bias. 相似文献
73.
Edge geometry influences patch-level habitat use by an edge specialist in south-eastern Australia 总被引:1,自引:1,他引:0
We investigated patterns in habitat use by the noisy miner (Manorina melanocephala) along farmland-woodland edges of large patches of remnant vegetation (>300 ha) in the highly fragmented box-ironbark woodlands
and forests of central Victoria, Australia. Noisy miners exclude small birds from their territories, and are considered a
significant threat to woodland bird communities in the study region. Seventeen different characteristics of edge habitat were
recorded, together with the detection or non-detection of noisy miners along 129 500-m segments of patch edge. Habitat characteristics
ranged from patch-level factors related to patch-edge geometry to site-level floristic factors. Backward (stepwise) logistic
regression analyses were used to identify habitat characteristics that were associated with the occupancy of a site by noisy
miners. After accounting for the effects of spatial autocorrelation on the occurrence of noisy miners along edges, we identified
projections of remnant vegetation from the patch edge into the agricultural matrix (e.g., corners of patches, peninsulas of
vegetation) and clumps of trees in the agricultural matrix within 100 m of the edge as significant predictors of the occupancy
of edges by noisy miners. This relationship was also confirmed in two other geographically and floristically distinct habitats
within Victoria. The use of edges with projections by noisy miners may confer advantages in interspecific territorial defence.
In light of these results, we advocate revegetation strategies that attempt to enclose projections within 100 m of the edge,
with fencing placed out to this new boundary, to reduce the likelihood of colonisation and domination of an edge by noisy
miners. Our study highlights the need for greater consideration to be given to the patterns in habitat use by aggressive edge
specialists, particularly in relation to patch-edge geometry and other human-induced components of landscapes. 相似文献
74.
Evaluation of potential serum biomarkers of hepatic fibrosis and necroinflammatory activity in dogs with liver disease
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75.
Dogs with acute myeloid leukemia or lymphoid neoplasms (large cell lymphoma or acute lymphoblastic leukemia) may have indistinguishable mediastinal masses on radiographs
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Erin Epperly Kelly R. Hume Steven Moirano Tracy Stokol Joanne Intile Hollis N. Erb Peter V. Scrivani 《Veterinary radiology & ultrasound》2018,59(5):507-515
Acute myeloid leukemia is an uncommon hematopoietic neoplasm of dogs that should be differentiated from lymphoid neoplasms, such as lymphoma, because of different treatment protocols and a worse prognosis. Thoracic radiography is performed frequently in dogs with suspected hematopoietic neoplasia, and detecting a mediastinal mass often prioritizes lymphoma as the most likely diagnosis. However, we have observed a mediastinal mass in several dogs with acute myeloid leukemia and hypothesized that (1) the frequency of a mediastinal mass was higher and (2) the size of the mass was larger in dogs with acute myeloid leukemia compared to dogs with lymphoid neoplasms. In this analytical study (observational, retrospective, and cross‐sectional), the sample population included 238 dogs with hematopoietic neoplasia. These dogs were divided into lymphoid (large cell lymphoma, acute lymphoblastic leukemia) and myeloid groups based on standard phenotyping tests. A mediastinal mass was detected during thoracic radiography in 73/218 (33%) and nine of 20 (45%) dogs in the lymphoid and myeloid groups (P = 0.21), respectively. The median size ratio of mediastinal mass to cardiac silhouette was 0.20 and 0.23 in the lymphoid and myeloid groups (P = 0.96), respectively. Additionally, we observed normal thoracic radiographs in 111/218 (51%) dogs in the lymphoid group and nine of 20 (45%) dogs in the myeloid group. In conclusion, acute myeloid leukemia should be considered when a mediastinal mass is detected during radiography in dogs with suspected hematopoietic neoplasia—but the presence or size of a mediastinal mass does not differentiate between myeloid and lymphoid neoplasms. 相似文献
76.
Joerg Henning Kate A. Henning Ngo Thanh Long Nguyen Truc Ha Le Tri Vu Joanne Meers 《Tropical animal health and production》2013,45(3):837-848
Ducks are considered to play a major role in the spread of highly pathogenic avian influenza (HPAI) H5N1 in Viet Nam, but detailed information on their management is limited. We distinguished two different systems (1) stationary duck flocks that are not commonly driven to rice fields beyond village boundaries and that are confined overnight on farms and (2) moving duck flocks that are intentionally driven to rice fields beyond village boundaries, that are not returning to home farms for extended periods and that are housed overnight in temporary enclosures in rice paddies. A total of 115 stationary and 22 moving flock farmers were interviewed in 2007 in the Mekong Delta of Viet Nam. Moving duck flocks are larger than stationary flocks, which is indicative of their more commercial production. Moving flock farmers apparently are more aware of HPAI risks than stationary flock farmers, as their flocks are more likely fully vaccinated and have less contact with chickens during scavenging. On the other hand, the spread of HPAI virus between birds might be promoted by moving duck flocks as they repeatedly use transport vehicles and numerous rice paddies for scavenging and are often visited by hatchery owners in the field for purchasing duck eggs. In addition, long distances travelled by moving duck flocks might also result in widespread dissemination of HPAI virus. Further studies are necessary to describe HPAI prevalence and travel patterns of moving duck flocks and to explore the moving duck flock network in detail. 相似文献
77.
Rodents are efficient invaders on a global scale and pose a significant threat to native biotas, particularly in systems such as oceanic islands which support a reduced suite of mammals. Pacific rats (Rattus exulans) are implicated in extinctions, range restrictions and declines of vulnerable endemic faunas throughout the Pacific. However, research into the behavioural and ecological modifications that enable native species to persist in the presence of Pacific rats is scant. We examined the population structure, behaviour and microhabitat use of Duvaucel’s geckos (Hoplodactylus duvaucelii; radio-telemetry), and Pacific rats (spool-and-line tracking) on three New Zealand offshore islands with different histories of rat incursions and eradication: (1) Green Island, historically rat-free, (2) Korapuki, from which rats were eradicated 20 years ago, and (3) ōh?¯nau, before and 6 months after rat eradication. Although Pacific rats and Duvaucel’s geckos shared habitat at a broad spatial scale, little overlap in micro-habitat use existed where they were sympatric. In the presence of rats, Duvaucel’s gecko capture rates and recruitment were reduced. However, 6 months after rat eradication, and prior to any recruitment, capture rates of adult geckos increased fourfold and geckos were using a greater proportion of habitat preferred by rats. Thus, we provide strong empirical evidence that Pacific rats ecologically displace Duvaucel’s geckos. Highly plastic spatial avoidance behaviour by native prey species in response to the presence of introduced rodents may enable geckos to persist in sympatry with rodents at least in the short-term. 相似文献
78.
OBJECTIVE: To examine associations of various psychosocial factors with fruit and vegetable intake in African-American adults. METHODS: A cross-sectional survey of a population-based sample of 658 African-Americans, aged 18-70 years, in North Carolina. Information was collected on diet-related psychosocial (predisposing, reinforcing and enabling) factors based on the PRECEDE (Predisposing, Reinforcing, and Enabling Constructs in Educational Diagnosis and Evaluation) planning framework; demographic, lifestyle and behavioural characteristics, and fruit and vegetable intake. RESULTS: The mean participant age was 43.9 years (standard deviation 11.6), 57% were female and 76% were overweight/obese. Participants expressed healthy beliefs regarding many of, but not all, the psychosocial factors. For example, although half of the respondents believed it is important to eat a diet high in fruits/vegetables, only 26% knew that >or=5 daily servings are recommended. The strongest associations of the psychosocial factors with fruit/vegetable intake were for predisposing factors (e.g. belief in the importance of a high fruit/vegetable diet and knowledge of fruit/vegetable recommendations) and one reinforcing factor (social support), with differences between the healthiest and least healthy responses of 0.5-1.0 servings per day. There was evidence of effect modification by gender in associations between psychosocial factors and fruit/vegetable consumption (e.g. self-efficacy was only significant in women), with higher intakes and generally healthier responses to the psychosocial variables in women than men. CONCLUSIONS: Interventions to increase fruit/vegetable intake in African-Americans may be more effective if they focus primarily on predisposing factors, such as knowledge, self-efficacy and attitudes, but not to the exclusion of reinforcing and enabling factors. The psychosocial factors that are targeted may also need to be somewhat different for African-American men and women. 相似文献
79.
Yarwood J 《Veterinary microbiology》2006,117(1):71-74
The childhood immunisation programme in England aims to achieve and maintain high vaccine coverage so that no child needlessly suffers from a vaccine preventable disease. As part of the programme, parents must have appropriate support from health professionals and have information available to them to make informed decisions about their choices. Even though immunisation is voluntary in England, coverage is generally high. It has been estimated that only 0.33% of parents do not consent to their child being included in a computerised database that schedules immunisation appointments. Parental attitudes, experiences and social grade are influential in determining whether a child receives a vaccine. Personal experience and knowledge of diseases influence parental perceptions about the seriousness of diseases and their likelihood of being affected by it. In societies where immunisation programmes have been successful, the challenge is maintaining high levels of vaccine coverage. In the absence of disease, the threat of that disease rapidly disappears and anxieties about the vaccine's safety may increase. A fall in vaccine coverage can lead to the return of disease as happened in the UK when rates of pertussis immunisation plummeted in the 1970s. Further perceived threats may also affect vaccine uptake, for example, the MMR controversy dating from 1998. The article outlines the MMR debate in the UK, the communication of risk and benefit and the management of information to the public. It will share lessons learned and examine how they might apply to the veterinary programme. 相似文献
80.