副猪嗜血杆菌感染诊断方法和最新基因分型方法的研究进展

副猪嗜血杆菌可引起猪格拉塞病和其它许多疾病,对与该茵有关的疾病进行诊断通常依赖于临床症状、病理变化和细菌分离,但由于有无毒菌株(nonvirulent strain)的存在及其在健康仔猪上呼吸道上的早期定殖,使得对该菌的诊断变得较为复杂.而且,在同一猪场甚至是同一只猪体内可能存在多种不同的菌株,因此确定可导致临床发病的特定菌株显得尤为重要.最近,科研人员开发了一些针对副猪嗜血杆菌的基因分型方法,目的是确定该茵的基因型与其毒力强度之间的关系.由于缺乏副猪嗜血杆菌完整基因组序列及其致病因子(virulence factor)的知识,因此将副猪嗜血杆菌的基因型与其毒力联系起来极富挑战性.     

Assessing the benefits of the marine protected area of Punta Coles,southern Peru (south-east Pacific) on productivity of conspicuous benthic species using pre-image population analysis

1. The coastal marine protected ecosystem at Punta Coles (as a part of the Reserva Nacional de Islas, Islotes y Puntas Guaneras) is located in a highly exploited area in southern Peru and contains several commercial, bioengineering and other benthic species.
2. Pre-image population analysis was used to estimate the transient values of intrinsic growth rate (r) based on biomass and density time series as a proxy of productivity to assess the effectiveness of protection.
3. The outcomes obtained showed that the gastropods Concholepas concholepas, Fissurella latimartiginata and the tunicate Purya chilensis showed a reduction of productivity during recent years, whilst the sea urchin Loxechinus albus, the barnacle Balanus laevis and the bivalve Semimytilus algosus showed an opposite pattern. Several species exhibited a chaotic dynamic, coinciding with the highest productivity values. In 2016 and 2017, several species exhibited a reduction of their abundance which could be delayed responses explained by changes in oceanographic conditions (reduction of coastal upwelling), La Niña event and illegal harvest.
4. The above notwithstanding, the results suggest that effective protection of benthic species in the protected ecosystem of Punta Coles have been partially accomplished. Therefore, this work could be considered a baseline study, permitting the subsequent monitoring of productivity of the main species inhabiting the coastal area of Punta Coles.
5. Pre-image population analysis could be used as a complimentary analytical tool since it enables the evaluation of transient population parameters (e.g. productivity) thus aiding population management, conservation and monitoring decisions.