HISTOPATHOLOGICAL FINDINGS IN PIGS OF VARIOUS AGES SUFFERING FROM SPONTANEOUS INFECTION WITH THE PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS (PRRSV)
J. Darbes et al., HISTOPATHOLOGICAL FINDINGS IN PIGS OF VARIOUS AGES SUFFERING FROM SPONTANEOUS INFECTION WITH THE PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS (PRRSV), Journal of veterinary medicine. Series A, 43(6), 1996, pp. 353-363
A retrospective study was carried out to investigate the morphology of
29 routinely necropsied German Landrace pigs of various ages, namely
five fetuses, eight neonates, five suckling piglets and 11 weaners, be
ing either serologically PRRSV-positive or born or aborted from PRRSV
positive sows. Virus antigen was immunohistochemically demonstrated in
12 out of 27 (44 %) lungs tested. The distinguishing histopathologica
l features of PRRSV-induced spontaneous disease are interstitial pneum
onia accompanied by secondary inflammatory alterations that become mor
e and more pronounced with increasing age, and vascular alterations hi
therto not described in animals of these age groups. The latter consis
t of vasculitis of the medium-sized arteries and occasionally of the v
eins, mainly in the lungs but also in other organs, and of perivascula
r lymphoplasmacytic infiltrates of various degrees of frequency and or
gan distribution, but present above all in the CNS-including the menin
ges and in the lungs. These findings, which suggest vasculotropism on
the part of the PRRSV, may facilitate the histopathological diagnosis
of PRRSV infections in routinely examined material.