Pharmacodynamics of amoxicillin against field isolates of Streptococcus parauberis from olive flounder (Paralichthys olivaceus)

Olive flounder is the most important species for the Northeast Asian fish farming industry. However, this species is substantially affected by multiple infectious agents, including Streptococcus parauberis. Evaluation of antibiotics before their application is critical to treat infections and prevent drug resistance. Therefore, in this study, the pharmacodynamics of amoxicillin (AMX) and other antimicrobials against the planktonic‐ and biofilm‐forming bacteria were assessed. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and Time–kill curve assay were analysed using micro‐dilution method. The minimum biofilm eradicating concentration (MBEC) was determined using the Calgary Biofilm device. The effects of temperature, pH, hardness and salinity were detected for both planktonic‐ and biofilm‐forming bacteria. The MIC of AMX ranged from 0.015 to 2 μg/ml, whereas that of cephalexin (CEP), enrofloxacin (ENR) and oxytetracycline (OTC) ranged from 0.125 to 256, 0.125 to >512 and 0.25 to >512 μg/ml respectively. No bacteria were resistant against AMX, while the percentage of resistance to CEP, OTC and ENR were 68.7%, 52.6% and 11.1% respectively. The IC₅₀ of AMX, CEP, ENR and OTC was 0.03, 0.091, 0.015 and 0.213 μg/ml respectively. The MBEC of amoxicillin against S. parauberis ranged from 0.5 to 16 μg/ml. Higher rates of bacterial growth were obtained at 30°C, pH = 8 and salinity of 7.5–10 ppt. The hardness of the media suppressed the bacterial growth. In conclusion, AMX was found to be effective against both the planktonic and the biofilm forms of the prominent fish pathogen, S. parauberis.     

江西地方品种鸡禽白血病病毒感染状况的研究

为了解江西省地方品种鸡群中禽白血病病毒的感染状况,利用针对禽白血病病毒(ALV)J亚群抗体和群特异性P27抗原的商品化ELISA检测试剂盒,对江西省12个种鸡企业的6个地方品种鸡进行禽白血病感染情况调查。结果显示江西几个地方品种鸡ALV的感染相当严重,迫切需要净化。但不同品种鸡的P27抗原的检出率与ALV-J抗体的检出率有一定差异。P27抗原阳性率最高的为JXDF4品种鸡(36.67%),其次为JXDF5、JXDF1、JXDF3、JXDF6、JXDF2品种鸡。与P27抗原检出情况类似,JXDF4、JXDF5的ALV-J抗体阳性率相对较高,分别为15%、30%,而其他4个地方品种的鸡群ALV-J抗体阳性率相对较低(10%)。调查还显示,同一品种鸡在不同种鸡场之间的ALV-J感染率差异较大。试验结果为各种鸡场开展净化工作提供了科学依据。     

Case studies on eradicating the Asiatic cyprinid Pseudorasbora parva from fishing lakes in England to prevent their riverine dispersal

• 1. The topmouth gudgeon Pseudorasbora parva has proved to be a highly invasive pest fish species in mainland Europe following introduction from Asia, and was first recorded in the wild in the UK in 1996. Distribution has increased markedly since 2002, with recordings now from 32 sites, the majority being lakes.
• 2. In infested UK lakes, populations establish rapidly and become dominant in the fish community (often >97% by number); densities to over 60 m^?2 have been recorded, with the majority of individuals <70 mm. The species also hosts a novel pathogen not previously recorded in the UK. It has, therefore, been identified as a significant concern to native fish communities and deserving of an appropriate response by regulatory authorities.
• 3. Where populations have been detected in lakes with connection to river catchments, actions have been taken to prevent riverine dispersal. Control measures are put in place, and eradication programmes designed and initiated. This paper details case studies on three completed eradication operations, two that utilized the piscicide rotenone, the other, de‐watering and disinfection.
• 4. Each case study has, so far, been successful in eradicating the topmouth gudgeon population and has resulted in approximately 280 km of river length being protected from their dispersal. Application of rotenone was the most cost‐effective eradication method at approximately £2 per m² of water area treated.
• 5. These case studies demonstrate that riverine dispersal of invasive fish from infested connected lakes can be prevented by eradication. Outputs can be used to develop a strategy to manage the increasing distribution of topmouth gudgeon—and other invasive, pest fish—in the UK.

Copyright © 2008 John Wiley & Sons, Ltd.     

Comparative fishing trials for <Emphasis Type="Italic">Charybdis japonica</Emphasis> using collapsible box-shaped and dome-shaped pots

ABSTRACT:   Comparative fishing trials were undertaken with two commercial collapsible pots for the crab Charybdis japonica . One pot was box-shaped with two slit entrances at the ends, while the other was dome-shaped with two open funnel entrances. Pots were placed at the bottom of a pond that is connected to Kagoshima Bay. Fishing trials were carried out using a 1-day soaking time; the bait used was mackerel. The box-shaped pot had higher catches of crabs and non-target organisms, but the number of large crabs (carapace width >8 cm) was almost half as many as that caught with the dome-shaped pot. The catch of non-target species was also greatly reduced in the dome-shaped pot, and fish caught were mostly enmeshed in the netting. The reduction in catches of small crabs and non-target organisms was due to the nature of the dome-shaped pot's larger mesh size and open entrances, which allowed for escape. The dome-shaped pot seemed more efficient for harvesting commercial size crabs, while the box-shaped pot seemed better for removing all crab sizes.     

Change of fish fauna in ponds after eradication of invasive piscivorous largemouth bass,Micropterus salmoides,in north‐eastern Japan

• 1. The change in fish fauna was monitored in ponds within irrigation systems in Iwate prefecture, north‐eastern Japan to evaluate the effectiveness of eradicating the invasive piscivorous largemouth bass, Micropterus salmoides.
• 2. Eleven study ponds were categorized into three pond groups: bass‐dwelling (n=3), bass‐eradicated (n=3) and non‐invaded ponds (n=5).
• 3. Species richness and diversity, which temporally decreased in bass‐dwelling ponds, increased in bass‐eradicated ponds. Furthermore, in bass‐eradicated ponds, the mean numbers of topmouth minnow and freshwater goby were gradually restored, but in bass‐dwelling ponds the numbers decreased and both species eventually disappeared.
• 4. Although the eradication of piscivorous invaders is helpful for restoring fish species diversity in ponds, its effectiveness varies among species, and other alien fish such as the rose bitterling (Rhodeus ocellatus ocellatus) often invade and proliferate in the bass‐eradicated ponds.
• 5. To ensure successful restoration of native biota and avoid undesirable results, it is necessary to plan and implement continuous monitoring and adaptive management after eradication of alien predators. Copyright © 2010 John Wiley & Sons, Ltd.

     

Regular monitoring and targeted removals can control lionfish in Mediterranean Marine Protected Areas

1. A lack of biosecurity in the Suez Canal has combined with global warming and other human pressures to cause abrupt changes in the Mediterranean Sea. Throughout this region an influx of species is influencing the outcome of efforts to protect and restore nature.
2. Despite calls for targeted removals of invasive species from protected areas, there is limited information about the effectiveness of this course of action from both an ecological and a socio-economic perspective. In this study, coordinated removals of lionfish (Pterois miles) by volunteers/scuba divers at three marine protected sites in Cyprus were conducted.
3. The removal efficiency was monitored using visual-census surveys and citizen science data. Removals significantly decreased lionfish numbers but long-term suppression of lionfish would require monitoring and repetition of removals when necessary, since population recovery was sometimes rapid.
4. Citizen science yielded the data needed to understand lionfish population changes and guide the timing of removal events, but was characterized by large variation and potential outliers, highlighting the need for large sample sizes.
5. Questionnaire surveys were used to assess the social impact of participation in lionfish removals; these showed that involvement had a strong positive impact on knowledge about lionfish and motivation to support marine conservation activities – the divers were even willing to pay extra to remove lionfish.
6. Management reforms would be needed to capitalize on this societal motivation, and enable effective lionfish removals by scuba divers, coordinated by competent authorities. The EU aims to protect at least 30% of the marine waters by 2030. Removal events could help shield selected conservation sites from the adverse effects of lionfish and at the same time help establish links with local communities, strengthening the sustainable use of marine systems both at corporate and at societal levels.

     

Failure by design: lessons from the recently rescinded light brown apple moth (Epiphyas postvittana) eradication program in California

This article was motivated by the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) announcement that on 17 December 2021 it rescinded Federal Orders of 2 May 2007 that regulated (what was believed to be) a new outbreak of the light brown apple moth (LBAM, Epiphyas postvittana (Walker)) in the mainland United States. Our article follows from, and builds on, a 2013 article published by Carey and Harder that outlined major concerns about the LBAM eradication program including the need, cost, safety, practicality, and feasibility of the program and the public opposition to it. The program began with an emergency order based on USDA claims of billions of dollars in potential crop losses and the need to circumvent safety review processes to urgently prevent the pest's establishment. The program ended with the realization by government decision-makers, 14 years after initiating the program, that LBAM posed no quarantine-level threat in the first place and with no evidence of any economic damage done by the insect. This article summarizes the mistakes made in devising and carrying out what has ultimately proven to be one of the most oversold, overhyped, misguided, ill-advised, unnecessary, and costly programs in the recent history of insect eradication programs in California. Termination of the LBAM program by USDA-APHIS presents an opportunity to review the program to identify lessons learned and provide recommendations to help avoid similar mistakes in future invasive species response programs. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

我国牛羊源人畜共患病的防控现状

我国牛羊业迅速发展同时增加了包括布鲁氏菌病、结核病、血吸虫病和包虫病等牛羊源人兽共患病的流行风险。本文具体介绍了我国人兽共患病的流行现状,从健全法规、完善补偿制度、加强检验和流动控制、加快相关技术的研发进程等政策层面上对影响防控效果的主要问题进行了分析,以期为提高我国牛羊源人兽共患病防控水平提供帮助。     

Disperser communities and legacies of goat grazing determine forest succession on the remote Three Kings Islands, New Zealand

Many remote islands are degraded as a result of deforestation and browsing of vegetation by introduced goats. Goat eradication is therefore a focus for island restoration, but there are few long-term records of change on islands after eradications. In 1946, three permanent plots were established immediately after goats were eradicated from Great Island (Manawa Tawhi), 60 km from northern New Zealand, and provide a 57-year record of change across a sequence of forest succession. Since 1946, the native and non-native bird communities that disperse 75% of the woody flora have increased from six to eight species and bird-dispersed woody plants in plots have increased from 7 to 11 species. After 1946, palatable trees were recruited in the plots. Unpalatable understorey sedges, present when goats were abundant, have persisted and may impede tree seedling establishment. Of the bird-dispersed woody plant species, 41% occur in the plots compared with 67% of the non-bird-dispersed species. Large-seeded species were unable to germinate away from parents until native pigeons Hemiphaga novaeseelandiae were present during the last decade. Forest succession is a consequence of interactions between the legacy of goat grazing and current disperser communities. Survival of seed-limited rare plants is not guaranteed in these circumstances. Although non-native goats no longer influence succession directly, non-native birds have been and remain important components of the disperser community. Our study supports the view that a whole-ecosystem understanding of the interactions between native and non-native species is needed to predict the consequences of eradications on islands worldwide.     

苏皖地区规模化鸡场禽白血病净化的初步研究

基于苏皖地区禽白血病(AL)流行病学调查结果,本研究参考国际AL净化方案,针对该病在苏皖地区的流行特点,选择代号为DYAH91和DYJS31的两个规模化地方品系鸡群开展了禽白血病净化初步研究。经过一个世代的净化更替,DYAH91鸡群p27抗原阳性率由14.4%下降到8.1%,p27抗体阳性率由3.4%下降到1.0%,A/B亚群抗体阳性率由5.7%下降到2.2%,病毒分离阳性率由3.1%下降到0.45%;DYJS31鸡群,p27抗原阳性率由40.7%下降到2.8%,p27抗体阳性率由18.7%下降到3.3%,A/B亚群抗体阳性率由10.2%下降到1.4%,J亚群抗体由1.7%下降到1.4%,病毒分离阳性率由4.1%下降为0。以上结果表明通过净化程序的实施,鸡群ALV阳性率显著下降,净化方案效果确实。