背景:猪对几种反刍动物病原体易感,包括柯西拉·伯内蒂,Schmallenberg病毒(SBV)和牛病毒性腹泻病毒(BVDV)。这些病原体已经在猪群体中描述过,尽管目前尚不清楚感染的动态和对猪场的影响。这项工作的目的是评估坎帕尼亚地区猪种群中这些感染的存在,意大利南部,并评估与更大暴露风险相关的风险因素。
结果:测试了属于32群的总共414份血清样品中是否存在抗SBV抗体,柯西拉,和BVD使用商业多物种ELISA试剂盒。SBV(5.3%)是最常见的病原体,其次是柯西氏菌(4.1%)和BVD(3%)。研究中包括的风险因素(年龄,性别,省,耕作制度,反刍动物密度和主要反刍动物种类)对暴露于BVD和柯西氏菌的可能性没有影响,除了位置,事实上,在卡塞塔省发现了更多的柯西氏菌血清阳性的猪。然而,单变量分析强调了年龄的影响,location,和接触SBV时的性行为。随后的多变量分析在统计学上证实了这些因素的重要性。SBV和BVDV的中和抗体的存在,在大部分阳性样品中,通过病毒中和试验和相位特异性ELISA进一步证实了针对柯西氏菌特定感染阶段的抗体。高中和抗体滴度的存在(特别是对于SBV)可能表明最近的暴露。17份阳性样本中有12份检测为抗柯西氏菌Ⅰ期或Ⅱ期抗原抗体阳性,表明存在急性和慢性感染(一只动物的两个阶段抗体均呈阳性)。
结论:我们的研究表明,来自意大利南部的猪对上述病原体的暴露是不可忽视的。进一步的研究是必要的,以充分了解这些感染在猪的动态,对生产力的影响,以及柯西拉的公共健康后果。
BACKGROUND: Pigs are susceptible to several ruminant pathogens, including
Coxiella burnetti, Schmallenberg virus (SBV) and bovine viral diarrhea virus (BVDV). These pathogens have already been described in the pig population, although the dynamics of the infection and the impact on pig farms are currently unclear. The aim of this work was to evaluate the presence of these infections in the pig population of the Campania region, southern Italy, and to evaluate the risk factors associated with a greater risk of exposure.
RESULTS: A total of 414 serum samples belonging to 32 herds were tested for the presence of antibodies against SBV,
Coxiella, and BVD using commercial multispecies ELISA kits. SBV (5.3%) was the most prevalent pathogen, followed by
Coxiella (4.1%) and BVD (3%). The risk factors included in the study (age, sex, province, farming system, ruminant density and major ruminant species) had no influence on the probability of being exposed to BVD and Coxiella, except for the location, in fact more pigs seropositive to
Coxiella were found in the province of Caserta. However, the univariate analysis highlighted the influence of age, location, and sex on exposure to SBV. The subsequent multivariate analysis statistically confirmed the importance of these factors. The presence of neutralizing antibodies for SBV and BVDV, or antibodies directed towards a specific phase of infection for Coxiella was further confirmed with virus-neutralization assays and phase-specific ELISAs in a large proportion of positive samples. The presence of high neutralizing antibody titers (especially for SBV) could indicate recent exposures. Twelve of the 17 positive samples tested positive for antibodies against
Coxiella phase I or II antigens, indicating the presence of both acute and chronic infections (one animal tested positive for both phases antibodies).
CONCLUSIONS: Our study indicates a non-negligible exposure of pigs from southern Italy to the above pathogens. Further studies are necessary to fully understand the dynamics of these infections in pigs, the impact on productivity, and the public health consequences in the case of Coxiella.