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81.
Victoria K. Gibbs Kelcie A. Brown Mickie L. Powell Stephen A. Watts 《Journal of the World Aquaculture Society》2011,42(3):364-369
Invasive and/or opportunistic organisms can negatively influence the success of sea urchin culture operations. To our knowledge, pests associated with sea urchin aquaculture have not been reported. In this study, we report the predatory association of the amphipod, Elasmopus levis (Amphipoda: Melitidae), with the sea urchin, Lytechinus variegatus (Echinodermata: Echinoidea), within an intensive inland culture system. Wild‐caught Ly. variegatus broodstock were placed in an intensive culture system, and within their canopy of spines or within transport seawater, populations of epifauna (including amphipods) and microfauna were most likely transferred into the culture system. A growing population of the amphipod developed over time. Associations of the amphipod with the sea urchin were observed to negatively affect the health of the sea urchin, and in some cases, epithelial tissue from the sea urchin test appeared to be consumed by the amphipod. An infestation of these amphipods in commercial sea urchin cultures could have the potential to be costly, and we recommend quarantine and/or water purification procedures be considered to prevent the introduction of pests to inland culture systems. 相似文献
82.
83.
Karen L. Astles Philip J. Gibbs Aldo S. Steffe Marcel Green 《Biological conservation》2009,142(11):2759-2773
Fisheries management in most areas of the world is concerned with the effects of resource exploitation on the broad marine environment that includes all major ecological components. However, all fisheries lack some information about many of these components particularly marine habitats and non-target species. Such data deficiencies make it difficult to identify priorities for management action. Qualitative ecological risk assessment is one tool that can be used by management to prioritise and evaluate management strategies. This paper demonstrates the mechanics of a qualitative ecological risk assessment applied to a currently operating data deficient commercial fishery. In particular, we demonstrate how the method applies to two distinct ecological components – marine habitats and harvested species – and shows how it contributed to the formation of management responses. The method combines biological and ecological information about each component with knowledge on the operations of the fishery. Using pre-defined decision rules and criteria the available information is used in a rigorous, transparent and repeatable manner. The paper demonstrates that the method can be used generally to apply to all ecological components of a marine fishery where data is deficient. 相似文献
84.
85.
Australian surveillance for avian influenza viruses in wild birds between July 2005 and June 2007 总被引:1,自引:1,他引:0
L Haynes E Arzey C Bell N Buchanan G Burgess V Cronan C Dickason H Field S Gibbs PM Hansbro T Hollingsworth AC Hurt P Kirkland H McCracken J O'Connor J Tracey J Wallner S Warner R Woods C Bunn 《Australian veterinary journal》2009,87(7):266-272
Objective To identify and gain an understanding of the influenza viruses circulating in wild birds in Australia.
Design A total of 16,303 swabs and 3782 blood samples were collected and analysed for avian influenza (AI) viruses from 16,420 wild birds in Australia between July 2005 and June 2007. Anseriformes and Charadriiformes were primarily targeted.
Procedures Cloacal, oropharyngeal and faecal (environmental) swabs were tested using polymerase chain reaction (PCR) for the AI type A matrix gene. Positive samples underwent virus culture and subtyping. Serum samples were analysed using a blocking enzyme-linked immunosorbent assay for influenza A virus nucleoprotein.
Results No highly pathogenic AI viruses were identified. However, 164 PCR tests were positive for the AI type A matrix gene, 46 of which were identified to subtype. A total of five viruses were isolated, three of which had a corresponding positive PCR and subtype identification (H3N8, H4N6, H7N6). Low pathogenic AI H5 and/or H7 was present in wild birds in New South Wales, Tasmania, Victoria and Western Australia. Antibodies to influenza A were also detected in 15.0% of the birds sampled.
Conclusions Although low pathogenic AI virus subtypes are currently circulating in Australia, their prevalence is low (1.0% positive PCR). Surveillance activities for AI in wild birds should be continued to provide further epidemiological information about circulating viruses and to identify any changes in subtype prevalence. 相似文献
Design A total of 16,303 swabs and 3782 blood samples were collected and analysed for avian influenza (AI) viruses from 16,420 wild birds in Australia between July 2005 and June 2007. Anseriformes and Charadriiformes were primarily targeted.
Procedures Cloacal, oropharyngeal and faecal (environmental) swabs were tested using polymerase chain reaction (PCR) for the AI type A matrix gene. Positive samples underwent virus culture and subtyping. Serum samples were analysed using a blocking enzyme-linked immunosorbent assay for influenza A virus nucleoprotein.
Results No highly pathogenic AI viruses were identified. However, 164 PCR tests were positive for the AI type A matrix gene, 46 of which were identified to subtype. A total of five viruses were isolated, three of which had a corresponding positive PCR and subtype identification (H3N8, H4N6, H7N6). Low pathogenic AI H5 and/or H7 was present in wild birds in New South Wales, Tasmania, Victoria and Western Australia. Antibodies to influenza A were also detected in 15.0% of the birds sampled.
Conclusions Although low pathogenic AI virus subtypes are currently circulating in Australia, their prevalence is low (1.0% positive PCR). Surveillance activities for AI in wild birds should be continued to provide further epidemiological information about circulating viruses and to identify any changes in subtype prevalence. 相似文献
86.
87.
G. Bennett J. Hickford H. Zhou J. Laporte J. Gibbs 《Research in veterinary science》2009,87(3):413-415
Lameness in the dairy industry in New Zealand causes a problem in lost production, animal welfare and associated costs. To understand what bacteria may be present on the hooves of lame dairy cattle in this grass-fed system, samples were scraped from lame dairy cows and examined for the presence of Fusobacterium necrophorum (F. necrophorum) and Dichelobacter nodosus (D. nodosus) using the polymerase chain reaction (PCR). The PCR primers were designed to detect the presence of the lktA gene, which encodes a leukotoxin unique to F. necrophorum, and the fimA gene of D. nodosus. A total of 148 hoof scrapings were collected by farm staff over the period September 2005 to May 2006. F. necrophorum was detected in 79/148 of the samples, while D. nodosus was detected in 7/148 of the samples. The frequent finding of F. necrophorum within dairy herds in New Zealand is noteworthy and the occasional finding of D. nodosus on some dairy cattle suggests a possible role in both ovine and bovine hoof pathology. 相似文献
88.
Understanding interactions between roadways and population structure and movements of wildlife is key to mitigating “road
effects” associated with increasing urbanization of the landscape. Aquatic turtles are a useful focal group because (1) population
persistence is sensitive to mortality of individuals upon roads; (2) turtles frequently move among wetlands and encounter
roads, and (3) turtles are an important component of vertebrate biomass in aquatic ecosystems. From 2005 to 2007, we examined
the effects of urbanization on local- and landscape-scale populations of turtles. To do so, we sampled and marked turtles
in 15 ponds arranged along a steep, urban–rural gradient in central New York State. We captured 494 turtles, representing
327 individuals, the majority of which were common snapping turtles Chelydra serpentina (n = 191) and eastern painted turtles Chrysemys picta picta (n = 122). At the local population (pond) scale, a higher proportion of female snapping turtles in ponds was associated with
lower road densities within 500 m of ponds. The mean size of both species of turtle increased in ponds with a lower density
of roads within 100 m. At the landscape-level, we observed fewer turtles dispersing through urbanized habitat than forested,
and fewer movements through areas with a higher density of roads. Our study suggests that roads alter both local- and landscape-level
turtle populations through a loss of female turtles, and by reducing movement between ponds. By extension, the study targets
key landscape features upon which to focus mitigation efforts. 相似文献
89.
Leah M Gibbs 《Land Degradation \u0026amp; Development》2009,20(3):347-348
90.
Successful adoption of a One Health approach could have far-reaching impacts on poverty alleviation, health and food security, particularly in developing countries through integrated control of neglected zoonoses. However, the practical implementation of this approach presents many challenges. Anna Okello and colleagues argue that, for effective implementation, lessons learned and 'best practice' must be led by national and regional stakeholders drawn from a variety of disciplines. High-profile regional and international institutions can play an important role in the global governance of One Health by encouraging individual countries to devise appropriate tailored solutions that are workable within their own context. 相似文献