Association of Myocarditis with High Viral Load of Porcine Circovirus Type 2 in Several Tissues in Cases of Fetal Death and High Mortality in Piglets. A Case Study

Abstract

Abstract. During a period of 1.5 months, a newly established pig herd experienced a high number of mummifications and stillbirths, a high neonatal mortality rate, and many piglets with congenital tremors or hind leg ataxia. After clinical and histological investigations, the submitted animals were divided into 4 groups: mummified or stillborn (N 5 6), live born with myocarditis (N 5 5) (average age 22.8 days), live born without myocarditis (N 5 14) (average age 20.0 days), and control animals from a different herd (N 5 5) (newborn). Statistically significant differences were observed in the mean porcine circovirus 2 (PCV2) load among the 4 groups in the liver (P , 0.0001). The presence of PCV2 antigen within the myocardial lesions was confirmed by immunohistochemistry. A high load of PCV2 DNA was observed in myocardium, liver, and spleen from mummified or stillborn piglets (.1 3 10 7 copies per 500 ng DNA), lower in piglets with myocarditis (.1 3 10 5 copies per 500 ng DNA), and even further lower in pigs without myocarditis (,1 3 10 5 copies per 500 ng DNA), whereas no PCV2 DNA was detected in the control animals. Myocardium, liver, and spleen were well suited for routine testing of fetuses and young piglets by quantitative real-time polymerase chain reaction. Neither porcine parvovirus nor encepaholomyocarditis virus was detected. These results indicate that the PCV2 infection might have been of etiological importance for the fetal deaths and piglet mortality observed in this herd.

Lawsonia intracellularis and Porcine Circovirus type-2 infection in Estonia

“…Similar pathomorphological changes as found in our study are described in several other works (Mikami et al 2005, Segales et al 2005, Martinez et al 2006, Brunborg et al 2007, Phaneuf 2007.…”

PMWS-like Lesions in Preweaned Crossbred Piglets Naturally Infected with Porcine Circovirus 2 in India

“…Presence and distribution of PCV2 antigen in various target tissues showing lesions characteristic of PMWS were similar to previous findings (Brunborg et al, 2007;O'Connor et al, 2001;Pallares et al, 2002;Rovira et al, 2002). Further, viral nucleic acid could be successfully demonstrated by ISH using DIG-labeled probe in lungs, heart, liver, lymph nodes and tonsil and these findings were similar to those reported earlier (Kim and Chae, 2001;Park et al, 2005).…”

Vascular lesions and pneumonia in a pig fetus infected by porcine circovirus type 2

“…The heart was not affected and was not further examined by either histology or IHC. In previous studies, the myocardium and the liver were shown to contain the highest amounts of PCV2, and the most consistent tissue lesions were found in the myocardium (West et al, 1999;Brunborg et al, 2007). The amount of PCV2 was reported to diminish with increased fetal age, and the virus is known to accumulate in the lymphoid organs around parturition (Sanchez et al, 2003).…”