摘要
胎兒的損失與仔豬離乳前死亡一直是商業化豬場重要的經濟損失。一般豬場胎兒損失 (死產、木乃伊胎) 的比率約為5-15％。而台灣商業化豬場其流產與死產比例佔胎兒死亡率的27.3％。為針對豬隻流死產胎進行傳染性病原的調查，並利用間接原位雜交反應 (indirect ISPCR) 了解豬第二型環狀病毒在胎兒組織中的親和性，本研究將以PCR與RT-PCR調查九種豬隻傳染性繁殖障礙病原；其中包含豬小病毒、豬第二型環狀病毒、假性狂犬病病毒、豬瘟、豬繁殖與呼吸道綜合症病毒、日本腦炎病毒、布氏桿菌、鉤端螺旋體、弓蟲等九種病原。在實驗期間共蒐集了52頭足月分娩的死產胎以及6頭懷孕日期小於109天的流產胎。在進行病理剖檢與採集冷凍檢體後進行核酸萃取，之後進行PCR與RT-PCR檢測，並觀察組織病變。其結果在肉眼與組織病變檢查無特異性病灶；九種病原的PCR/RT-PCR檢測，僅兩例有豬第二型環狀病毒陽性病例，其他八種病原的分子檢測皆為陰性。以間接原位聚合酶鏈鎖檢測，在PCV2陽性胎兒的心臟心肌細胞與血管內皮以及腸系膜淋巴結淋巴濾泡的淋巴細胞中偵測出棕黑色陽性訊號。此結果顯示PCV2在台灣可能是引起流死產的危險因子之一，而大部分的流死產多和非傳染性因子有關。而間接原位聚合酶鏈鎖反應結果則和現今文獻一致，顯示PCV2對胎兒心臟的心肌細胞具有親合性。
並列摘要
Fetal losses and pre-weaning mortality are among the most important causes of losses in commercial swine herds. Usually, fetal losses (mummified fetuses and stillborns) can vary from 5 to 15%. But the abortion and stillbirth in the fetal mortality rate was 27.3％ in Taiwan. The aims of the present study were pathogens surveillance in the field cases of swine abortions or stillbirths, and using indirect in situ PCR to define PCV2 tissue tropism in aborted or stillbirthed cases. Nine reproductive pathogens were included in this study which are porcine parvovirus, porcine circovirus 2 (PCV2) , pseudorabies, porcine respiratory and reproductive virus (PRRS) , Japanese encephalitis, classical swine fever, Brucella suis, Leptospira sp., and Toxoplasma gondii. Fifty two at term stillbirths and six middle term abortions were collected. Nuclear acid were extracted from the homogenized visceral organs and PCR or RT-PCR were subsequently performed for molecular screening. After gross and histopathologic examination, no specificly lesion was observed in these fetuses. The molecular screeing results showed none of the pathogens were detected in the collected samples except 2 stillbirths were positive for PCV2. The indirect in situ PCR revealed that the PCV2 signals distribute discretely in the myocardium and germinal center of mesentery lymph node. The result suggests that PCV2 is the potential risk factor in swine stillbirth, although noninfectious risk factors are the major causes of stillbirth. The indirect in situ PCR results are consistent with the current studies, the heart is the PCV2 primary replicated organ in fetus.