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31.
S.R. Isberg P.C. Thomson F.W. Nicholas S.G. Barker & C. Moran 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2006,123(1):44-47
Mortality records of 1302 juvenile crocodiles were available for analysis. Crocodiles that were slaughtered during this study were treated as censored (n = 2151). Additionally, records from animals that had neither died nor been slaughtered, i.e. were still alive in the production system (n = 1582), were censored at the last date of data collection. There were a total of 3733 censored records. The data were all full‐sib records from 29 parental pairs from Janamba Croc Farm (Northern Territory, Australia), collected over nine consecutive years. Data were analysed using an extension of Cox's proportional hazards model to include frailty (random) terms to account for genetic effects. Heritability of log survival time for juvenile crocodile survival was 0.15 (SE 0.04). The probability of a juvenile crocodile surviving to day 400 was estimated to be only 51%. These results are the first to quantify juvenile survival in a captive breeding situation. Also, this is the first heritability estimate of crocodile survival and is a fundamental element in the development of a genetic improvement programme. 相似文献
32.
Recent quantitative site-based monitoring and qualitative aerial and ground traverses provide contrasting assessments of the
health of much of the arid shrublands of Western Australia extensively grazed by livestock (‘rangelands’). Although these
results seem incompatible, we explain the apparent contradictions based on landscape succession processes operating at multiple
levels of ecological organisation. Specifically, we suggest that the intact areas in which site-based monitoring is conducted
are contracting as catchment canalisation and desiccation increase. However, the impacts of these processes have not yet become
manifest at the site scale. The site-based system addresses important regional questions. These relate to the large, relatively
intact areas away from most active surface flows, which should be a focus for resource conservation, given practical limits
to repairing widespread degradation with low management inputs. We provide a complementary set of questions to provide a more
comprehensive audit of rangeland dynamics in the context of underlying hierarchical landscape patterns and processes that
might threaten intact areas. We recognise the need to match questions and levels of ecological organisation and the implications
these have for sampling. We also recognise the difficulty in producing concise statements of change for clients when reporting
on complex ecological issues and processes. Without a clearly articulated, and well understood, hierarchical model of pattern
and process within which apparently contradictory findings can be reported meaningfully, policy makers may be confused by
the results, with the consequent risk of policy inaction. 相似文献
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A new acylated quercetin glycoside, quercetin 3-O-(2-t-p-coumaroyl)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside-7-O-beta-D-glucopyranoside (1), together with the known 3-(3,4-dihydroxyphenyl)lactic acid (2) were isolated from Ranunculus lanuginosus leaves and identified on the basis of detailed spectral analysis, including 2D-NMR spectrometry and ESI-MS. 相似文献
38.
H. Hu A. Barker T. Harcourt‐Brown N. Jeffery 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1456-1463
Intracranial neoplasia is commonly diagnosed in dogs and can be treated by a variety of methods, but formal comparisons of treatment efficacy are currently unavailable. This review was undertaken to summarize the current state of knowledge regarding outcome after the treatment of intracranial masses in dogs, with the aim of defining optimal recommendations for owners. This review summarizes data from 794 cases in 22 previously published reports and follows PRISMA guidelines for systematic review. A Pubmed search was used to identify suitable articles. These then were analyzed for quality and interstudy variability of inclusion and exclusion criteria and the outcome data extracted for summary in graphs and tables. There was a high degree of heterogeneity among studies with respect to inclusion and exclusion criteria, definition of survival periods, and cases lost to follow‐up making comparisons among modalities troublesome. There is a need for standardized design and reporting of outcomes of treatment for brain tumors in dogs. The available data do not support lomustine as an effective treatment, but also do not show a clear difference in outcome between radiotherapy and surgery for those cases in which the choice is available. 相似文献
39.
Hannah J. Munro Lesley Berghuis Andrew S. Lang Laura Rogers Hugh Whitney 《Canadian journal of veterinary research》2014,78(2):140-144
Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are retroviruses found within domestic and wild cat populations. These viruses cause severe illnesses that eventually lead to death. Housing cats communally for long periods of time makes shelters at high risk for virus transmission among cats. We tested 548 cats from 5 different sites across the island of Newfoundland for FIV and FeLV. The overall seroprevalence was 2.2% and 6.2% for FIV and FeLV, respectively. Two sites had significantly higher seroprevalence of FeLV infection than the other 3 sites. Analysis of sequences from the FeLV env gene (envelope gene) from 6 positive cats showed that 4 fell within the FeLV subtype-A, while 2 sequences were most closely related to FeLV subtype-B and endogenous feline leukemia virus (en FeLV). Varying seroprevalence and the variation in sequences at different sites demonstrate that some shelters are at greater risk of FeLV infections and recombination can occur at sites of high seroprevalence. 相似文献
40.
Rebeccah McDowall Durda Slavic Janet I. MacInnes Hugh Y. Cai 《Canadian journal of veterinary research》2014,78(2):150-152
A real-time polymerase chain reaction (PCR) assay of the outer membrane protein (OMP) P2 gene was developed and used to test 97 putative Haemophilus parasuis pure cultures and 175 clinical tissue samples. With standard culture isolation as the gold standard, the diagnostic sensitivity and specificity of the PCR assay were determined to be 83% and 80%, respectively. 相似文献