Targeted elimination of the exotic termite,Nasutitermes corniger (Isoptera: Termitidae: Nasutitermitinae), from infested tracts in southeastern Florida

Populations of the arboreal termite, Nasutitermes corniger, discovered in Dania Beach, Florida in 2001 were surveyed and treated for eradication, beginning in 2003. Most N. corniger nest locations were cryptic and some nests contained over 1 million termites. Field efficacy of fipronil (Termidor® SC) and imidacloprid (Premise® 2) were compared in initial treatments, and fipronil was selected for termite-active sites through 2010. In 2006, expanded survey work was discontinued. By 2010 all sites within the original survey area were termite-free. In 2011, a new population of N. corniger was discovered beyond the original 2003 infested tracts. A new (2011–2012) survey revealed a total of four areas outside the original tracts that were infested with N. corniger. No tract treated with fipronil between 2003 and 2010 showed evidence of renewed termite activity in 2011–2012. New application procedures using nest-only and fipronil dust treatments were instituted in May 2012. Live termites were still found within the 2011–2012 treatment area as of November 2013. Very slow but continued spread of N. corniger in tropical urban Florida will have economic consequences as a result of nuisance and structural damage.     

Impact of area-wide malathion on predatory arthropods and secondary pests in cotton during boll weevil eradication in Texas

The boll weevil, Anthonomus grandis grandis, has been eradicated from much of the cotton producing region of the US and to-date eradication efforts continue in Texas. While providing long-term economic and environmental benefits, area-wide applications of malathion used by the eradication program have been implicated in the disruption of biological control of some cotton pests. This study evaluated the impact of the area-wide boll weevil eradication on abundance of predatory arthropods and key pests of cotton during four years in central Texas. Multiple applications of malathion ULV significantly reduced seasonal mean densities of spiders, predatory bugs (Orius spp. Pseudatomoscelis seriatus, Nabis spp., Geocoris spp.), Chrysopidae larvae and red imported fire ant, Solenopsis invicta, collected from the cotton canopy. In contrast, densities of beet armyworm, Spodoptera exigua, heliothine and other lepidopteron larvae, cotton aphid, Aphis gossypii, and adult and larval convergent lady beetle, Hippodamia convergens, often increased in cotton fields under boll weevil eradication. The density of total predators measured during the mid-season (period of blooming and early boll development) was significantly and negatively correlated with density of beet armyworm larvae during the late-season (boll maturation period). Results suggest that the community of predatory arthropods in the cotton canopy, rather than one or several key predators, is important in suppressing outbreaks of S. exigua and other lepidopteran pests in cotton. Furthermore, the potential to use densities of generalist predators in mid-season to anticipate late-season outbreaks of beet armyworm during boll weevil eradication is discussed.     

BIOECONOMICS OF INVASIVE SPECIES IN AQUATIC ECOSYSTEMS

When a biological invader is identified in an aquatic ecosystem, rapid response is critical, particularly if the invasive organism has the ability to spread rapidly. The first response should be to attempt to contain the invasion while further information is gathered to evaluate whether eradication is feasible. The eradication versus containment decision is studied by developing and using a stochastic dynamic programming model based on a simple biological spread function. Information requirements to calibrate the decision model for a specific invader are discussed and numerical analysis is undertaken to illustrate how the model can be used when only rough estimates of benefits and costs are available.     

一步法RT-PCR检测血清混合样品在BVDV清除计划中的应用

利用一步法RT-PCR对58份BVDV抗原阳性血清进行检测。试验证明,对OD450=0.3的标准血清,该方法的最低检出限为5μL/头,血清混合检测时至少可将60份OD450〉0.3的阳性血清等量混合。此外,RT-PCR与ELISA-Ag联合使用时,数学推导证明当混合样品为10～30个/份时,BVDV清除计划检测成本最低,相比单独使用ELISA-Ag,成本至少下降70%。综上,本试验确立的一步法RT-PCR灵敏度高,特异性好,联合ELISA-Ag使用,可大幅降低BVDV清除计划的检测成本,故值得推广使用。     

药物在猪肺炎支原体净化中的应用

猪支原体肺炎(猪气喘病)是由猪肺炎支原体引起的一种严重危害全球养猪业生产的传染病之一。到目前为止,控制该病最有效的方法就是彻底的净化病原。制定一个合理的用药方案是净化成功与否的关键。本文就猪肺炎支原体敏感药物做一介绍,并列举了国外不同净化程序的不同给药方案,为国内猪气喘病净化提供依据。     

Increased prevalence of Mycoplasma bovis in the Netherlands

Summary

The epidemiology, therapy, and prevention of M. bovis infections are briefly reviewed In a survey begun in 1982 M. bovis was found frequently in the respiratory of veal calves and beef cattle with respiratory problems. In replacement calves infected with respiratory disease in dairy herds, however, the organism has only been detected since 1986. Respiratory tract specimens collected from calves with respiratory disease were submitted for examination for M. bovis from 1986 to 1991 and originated from 83 herds. Mycoplasma bovis was detected in specimens from 59 of the herds, 20% of which were dairy herds and 80% fattening herds. Arthritis caused by M. bovis was observed in 12 herds until July 1991. Since 1976 when the first mastitis outbreak caused by M. bovis was diagnosed M. bovis has caused 14 more outbreaks. The number of diseased cattle varied from 1 tot 16 per farm, and clinical signs of mastitis varied from mild to severe. In all instances the infection has been eradicated from the herds. Because M. bovis can cause great losses in intensively reared cattle herds, it is advisable to separate purchased veal calves and beef cattle from dairy cattle to prevent further spread of M. bovis.     

The precautionary principle and biological invasion: the case of the House Sparrow on the Lesser Antilles

The capacity to react quickly to species introductions and to plan effective management countermeasures is always difficult, and methodology is lacking. This paper summarizes the different steps of a decision-making protocol applied to the recent establishment of an exotic species, the House Sparrow Passer domesticus, in the Lesser Antilles. This pest bird damages crops, fruits and stored food products and also competes with numerous hole-nesting birds in a large part of its range, and this requires more or less rapid management decision to limit its impact. In order to construct a base for decision-making in the Lesser Antilles case, we designed and conducted a brief biological study involving three spatial scales. At the regional scale, we defined the state of spread of House Sparrows throughout the West Indies. At the island scale, we estimated the number and distribution of breeding colonies. At the local scale, we estimated the numbers and behaviour of House Sparrows. To enable a quick decision to be made, we also suggested organizing a collective decision-making process applying a multi-actor guideline taking account of the different kinds of actors and levels of competence. We applied this method and we presented our results to a multi-actor workshop. The collective decision-making chose to apply the precautionary principle on one island (bird eradication) and to install both communications and monitoring plans. The procedure involving both multi-spatial scale assessment and a multi-actor workshop needs to be refined but its prospects are promising.     

Effects of physical barriers and eradication on recolonization of rodents in poultry farms

Abstract

Mus musculus, Rattus rattus and Rattus norvegicus are pests in poultry farms, causing economic losses and transmitting diseases. Control is commonly conducted through anticoagulant rodenticides, but this control is not effective through time. We aimed to assess the effect of rodent exclosure on long-term success of rodent control in poultry farms of the pampean region, Argentina, and to evaluate indirect estimators of rodent abundance. In both exclosure and non-exclosure sheds rodent abundance decreased significantly after eradication but mice populations showed a recovery, suggesting that the eradication was not complete. Rats did not recover, but the low abundance found at the beginning of the experiment does not allow an accurate conclusion.     

禽白血病研究进展

禽白血病是由反转录病毒科禽白血病 /肉瘤病毒群病毒 ( AL /SV)引起的禽类多种肿瘤性疾病的总称 ,感染率高 ,发病率低。 AL /SV可通过水平和垂直两种方式传播感染鸡群。鸡群感染此病会导致严重的经济损失 ,一是产生肿瘤 ,导致鸡的死亡 ;二是生产指标下降。但至今人类还不能有效的预防和治疗本病 ,控制禽白血病的主要方法是通过病原检测 ,淘汰阳性鸡 ,净化种群。国内外相继建立了多种检测禽白血病的方法 ,其中 EL ISA法能高效的检测到蛋清中的 AL SV抗原 ,具有敏感、简便、快捷、适用于大面积检测的特点 ,在种群净化中得到了广泛的应用 ,但 EL ISA诊断试剂盒在我国还未实现商品化。随着我国养禽业的发展以及科研、生产和检疫的需要 ,建立高效、实用的禽白血病检测方法 ,研究和控制本病将是今后的重要任务。文章就禽白血病的病原、流行病学、种群净化及防制等方面的研究进展进行了综述。