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21.
Current distribution of sarcoptic mange in wombats   总被引:2,自引:0,他引:2  
Objective To determine the distribution and prevalence of sarcoptic mange in wombats, particularly the common wombat ( Vombatus ursinus ).
Design Questionnaire survey in two parts.
Procedure Questionnaires were distributed to biologists, rangers, animal carers and naturalists. Part 1 of the questionnaire aimed to determine the present distribution of sarcoptic mange in wombats (103 responses). Part 2 invited respondents to assess the prevalence of sarcoptic mange in wombats over a 3 month period (four responses). Information on wombats from 66 localities was received. Each locality represented an area of about 2500 km2.
Results Mange was observed at 93% of localities surveyed and Sarcoptes scabiei was present in common wombats at 52% of localities. Sarcoptic mange was highly prevalent (22%) in two common wombat populations in Victoria. Anecdotal evidence suggested that mange epizootics are sporadic, cause significant morbidity and mortality and have a substantial effect on local abundance. The respondents did not report sarcoptic mange in either northern hairy-nosed wombats ( Lasiorhinus krefftii ) or southern hairy-nosed wombats ( Lasiorhinus latifrons ).
Conclusions Sarcoptic mange occurs in common wombat populations throughout the range of the common wombat including Tasmania and Flinders Island. While mange epizootics are sporadic, they have the potential to threaten the long-term survival of small, remnant populations.  相似文献   
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In vitro digestibility, fibre, lignin and protein were determined in 50 varieties of timothy differing markedly in maturity date. The grasses were field-grown as single plants and were sampled at 10% ear emergence, 30% flowering and the mature seed stage and were compared in four groups according to date of ear emergence.
Significant differences were found between maturity groups in digestibility and protein concentration particularly at the earlier growth stages. Considerable variation also occurred within maturity groups. Differences in digestibility, fibre, lignin and protein were significantly correlated with the number of days between 30 April and harvest date.
The results are discussed in the context of an appropriate evaluation scheme for timothy varieties.  相似文献   
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[目的]分析研究洪泽湖湖滨地区植物群落对湿地水环境的净化效果,为该区生态修复提供参考依据。[方法]以洪泽湖湿地国家级自然保护区典型湖滨带为研究对象,通过对该区的水草区和无草区环境特征进行野外调查,并结合室内试验,测定湖泊湿地水体的营养盐(N和P)、化学需氧量(COD)及透明度(SD)含量的变化,定量分析水生植被在生长过程中对湖泊湿地生态系统中水环境的净化效果,并对其可能存在的影响因素进行探讨。[结果]水生植被对洪泽湖湿地水环境中TN、TP、COD、Chla的去除作用及对SD含量变化有较明显的影响。水生植物之间的竞争可以抑制藻类的生长,减轻水体的富营养化情况。[结论]该试验为研究洪泽湖湖滨带生态修复及增强其自净能力提供理论依据。  相似文献   
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SUMMARY The proposal by the Zoological Parks Board of New South Wales to import 10 southern black rhinoceros (Diceros bicornis) from Zimbabwe as part of an international project for conservation of the species presented the Australian Quarantine and Inspection Service (AQIS) with a unique challenge. This importation is, at least in the modern era, the first importation of live herbivores from the African continent. Many of the serious animal diseases in the world are endemic in parts of Africa. Knowledge of which of these diseases infect wild species and may be transmitted from the wild species to domesticated species, is limited. This paper describes the strategies adopted by AQIS to facilitate the importation of rhinoceros while maintaining protection of Australian consumers, rural industries, domestic livestock and fauna against the entry and spread of unwanted pests and diseases.  相似文献   
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The ecology of avian influenza (AI) viruses in wild aquatic birds of Asia is poorly understood, especially for the H5N1 high pathogenicity AI (HPAI) viruses. From March 2006 through November 2008, 20 AI viruses were isolated in the Crimea region of Ukraine with an overall frequency of virus recovery of 3.3%. All the viruses were isolated from three species of dabbling ducks: mallard (Anas platyrhynchos), wigeon (Anas penelope), and garganey (Anas querquedula), making the frequency of virus recovery for dabbling ducks 6.3%. The viruses were predominantly isolated during the fall sampling period. All viruses were genetically and antigenically characterized. No H5N1 HPAI viruses were isolated, but other HA and NA subtypes were identified including H3N1 (2), H3N6 (3), H3N8 (4), H4N6 (6), H5N2 (3), H7N8 (1), and H10N6 (1) subtypes. All isolates were of low pathogenicity, as determined by the intravenous pathogenicity index of 0.00. For H5N2 and H7N8 isolates, the HA gene was sequenced and the phylogenetic analysis revealed possible ecologic connections of the Crimea region with AI viruses from Siberia and Europe. No influenza A isolates were recovered from other Anseriformes (diving ducks [two species of pochards] and graylag geese), Columbiformes (collared doves), Gruiformes (coot), and Galliformes (gray partridges).  相似文献   
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Zoledronate is a bisphosphonate frequently used for the treatment of hypercalcaemia of malignancy and tumour-associated bone pain in dogs, however, there is a paucity of information regarding its use in veterinary medicine. The aim of this retrospective study was to report the tolerability of zoledronate in the palliative treatment of cancer-bearing dogs and secondarily to to assess the efficacy of zoledronate for the treatment of hypercalcaemia of malignancy. Thirty-seven dogs (22 with tumour-associated bone pain and 15 with hypercalcaemia of malignancy) that received 114 zoledronate infusions were included. Tolerability was assessed by the absence of post-zoledronate hypocalcaemia or other adverse events as defined by Veterinary Cooperative Oncology Group-Common Terminology Criteria for Adverse Events criteria. Efficacy was assessed by comparison of available ionized calcium levels before and after zoledronate administration in hypercalcaemic dogs. In 79% of zoledronate infusions, no adverse events were reported. The majority of adverse events which occurred in the other 21% of infusions could be attributed to concurrent chemotherapy or the underlying neoplastic disease. There was a small but significant increase in creatinine following treatment with zoledronate, however, none of the dogs developed clinically significant renal disease. In eight hypercalcaemic dogs with available ionized calcium following zoledronate administration, ionized calcium decreased rapidly within 7 days following treatment with zoledronate. Zoledronate is well-tolerated with few recorded adverse events, however, monitoring of serum creatinine is advised. Zoledronate seems to be effective in the treatment of hypercalcaemia of malignancy.  相似文献   
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SUMMARY Weaned lambs were infected with Haemonchus contortus 35,28,21,14 and 7 days after treatment with moxidectin at 0.2 mg/kg and 35 and 14 days after treatment with ivermectin at the same dose rate. Worm counts 14 days after infection showed that moxidectin prevented the establishment of over 99% of infective larvae for 28 days and reduced the establishment rate at 35 days by 96%, relative to ivermectin. There was no difference in the protective efficacy of ivermectin at 14 or 35 days. The persistence of moxidectin is likely to provide advantages in nematode control, particularly when used as a strategic early summer treatment or as a pre-lambing treatment to ewes. Implications of the persistent activity of moxidectin for the development of resistance during the decay phase are discussed.  相似文献   
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