Porcine Reproductive and RespiratorySyndrome (PRRS) is proving to be a challenging disease to bring under control –and very costly to the industry.

豬繁殖與呼吸綜合癥（PRRS）被證明是最難控制的疾病，同時在畜牧業(yè)中損失也是相當大的。

A recent study from theUS puts the annual cost there at US$664 million – more than in 2005 and with agreater share of this cost in the breeding herd as some progress has been madein controlling the disease in growing pigs

. The US National Pork Board in the UShas suggests that, by developing a better understanding of themechanisms PRRS virus uses to evade the immune system, scientistswill be in a much better position to deal with the infection,

Thesyndrome affects the reproductive performance of breeding sows and slows growthrates among grower pigs and is considered the most costly disease facing NorthAmerican pork producers

. Several strategies have been used toaddress PRRS including the establishment of more than two dozen regional PRRSelimination projects across the US.

美國豬肉協(xié)會表明，通過進一步的了解PRRS病毒逃避機體免疫系統(tǒng)的機制，會對科學家研究控制PRRS 感染幫助很大。

美國最近的一項關(guān)于花費6.64美元關(guān)于種豬群的研究，在生長育肥豬的疾病控制上取得了一些進展。

該綜合癥主要影響母豬的繁殖性能和生長育肥豬的生長速度，被認為是北美豬肉生產(chǎn)者的頭號敵人。

對此美國采取了很多策略處理PRRS，包括建立超過24個區(qū)域的PRRS消滅計劃。

The Board’s Dr Lisa Becton acknowledges itis hard to know exact numbers but many farms see recurring issues with PRRS -both in terms of new outbreaks and the recurrence of the disease on farms thathad previously been affected.

該協(xié)會的LisaBecton博士承認很難估計具體數(shù)字，但是有很多農(nóng)場反映PRRS有反復性的規(guī)律，包括新的變異疫情還有之前感染過的再次復發(fā)。

She highlights that we do not yet fullyunderstand the mechanism that the virus uses to evade the pig’s immune system,which is one reason why vaccinating against one strain of the virus does notconfer complete or absolute protection against any other strain.

她強調(diào)我們尚未完全了解病毒是如何逃避免疫系統(tǒng)的機制，這也是為什么免疫接種后不能對某一種毒株或其他毒株產(chǎn)生完全免疫保護。

New research from Spain may help to shedsome light on these issues. Researchers of CReSA have demonstrated that inoculation with different PRRS virusstrains result in different virological and immunological outcomes andin different degrees of homologous and heterologous protection.

來自西班牙的研究可能對此做出解釋，來自CRESA的研究者證實接種不同的PRRS毒株會產(chǎn)生不同的病毒學和免疫學效果，和不同程度的同源和異源保護。

Their results indicate that almost oppositemodels of immune response to the virus could exist, depending on the strain:one based mainly in the development of neutralising antibodies (NA) with lowvirus-specific interferon-γ secreting cell (IFN-γ-SC) responses, the other withpredominance of IFN-γ responses and a poor development of NA.

結(jié)果表明可能存在幾乎相反的免疫模式。接種毒株后，一種會產(chǎn)生免疫抗體和低特異性的干擾素生。其他的會產(chǎn)生高強度的干擾素和低效價的中和抗體。

In virological terms - but not based onzootechnical parameters - heterologous immunity sometimes could be moreefficacious than the homologous one, the CReSA research team added

.在病毒學方面，不是機遇畜牧生產(chǎn)實際數(shù)據(jù)上，不同源的免疫效果好于同源免疫。

EU Member States have voted to remove theremaining health restrictions forclassical swine fever (CSF)in wild boar in Hungary. Surveillance carried out in 2012 and early 2013 hasshown that the disease has been eradicated.

歐盟成員過投票決定去除對匈牙利豬瘟野毒的限制，該國監(jiān)控表示，在2012年和2013年初豬瘟已經(jīng)被根除。

Finally, in health-related news, threeUS senators have introduced the bipartisanAntimicrobial Data Collection Bill,which aims to increase the data collected by the FDA on antibiotic use in farmanimals. The news has been applauded by Pew Charitable Trusts as a move towardsending antibiotic use for growth promotion.

     最后，關(guān)于衛(wèi)生的新聞，三位美國參議員引入兩黨抗生素收集草案，旨在通過FDA收集在農(nóng)場中使用的抗生素，該草案唄皮尤慈善信托基金所支持以結(jié)束抗生素的濫用。