Experimental Viral Myocarditis: Parvoviral Infection of Neonatal Pups

Abstract

Abstract. Myocarditis was produced in seronegative five-day-old pups by oral and by intraperitoneal inoculation of canine parvovirus. The disease was subclinical. Histologic lesions were compatible with, but less extensive than, those seen in naturally occumng canine parvoviral myocarditis. In pups necropsied 23 days after inoculation, scattered cardiac myocytes contained intranuclear inclusion bodies, and virus-infected myocytes were demonstrated by immunofluorescence. Degeneration and loss of cardiac myocytes usually was not associated with a cellular infiltrate. At 51 days after inoculation, the myocardium contained an extensive lymphocytic infiltrate which was sometimes associated with fragmented myocytes, and was often contiguous with areas of interstitial fibrosis. At 108 days after inoculation, inflammatory lesions had regressed, and there were multifocal areas of myocardial fibrosis.

Canine parvovirus: the worldwide occurrence of antigenic variants

“…Following an incubation period of 3-7 days, the disease can be characterized by two clinical forms, the enteric form that comprises vomiting, haemorrhagic diarrhoea, depression, loss of appetite, fever and dehydration in younger dogs (Nelson et al, 1979;Carman & Povey, 1985;Parrish, 1995;Hoelzer et al, 2008a). Myocarditis may be seen after infection of neonatal puppies, where the clinical signs are seen a number of weeks after infection (Meunier et al, 1984;Sime et al, 2015). Canine parvoviral infection is also characterized by a drop in the white blood cell counts as a result of the infection of the bone marrow infection and other lymphoid tissues (Kelly, 1978;Appel et al, 1979).…”

Surto de parvovirose cardíaca em filhotes de cães no Brasil

“…A vacinação ou exposição natural das cadelas ao agente possibilita o desenvolvimento de altos títulos de anticorpos, os quais podem ser transferidos aos filhotes, de forma transplacentária ou pelo colostro, conferindo-os proteção no período neonatal, de maior susceptibilidade (Meunier et al 1984, Parrish 1995. Assim, essa forma da doença é descrita ocorrendo apenas ocasionalmente e em neonatos ou filhotes que não receberam imunidade passiva ou nasceram de cadelas não vacinadas (Meunier et al 1984, Decaro & Greene 2012.…”

“…Assim, essa forma da doença é descrita ocorrendo apenas ocasionalmente e em neonatos ou filhotes que não receberam imunidade passiva ou nasceram de cadelas não vacinadas (Meunier et al 1984, Decaro & Greene 2012.…”

“…É possível que a infecção intrauterina do Parvovirus canino possa ter contribuindo para a ocorrência de um natimorto, apesar de não existirem evidências de que a infecção intrauterina ocorra espontaneamente, essa via de infecção já foi reproduzida experimentalmente (Lenghaus & Studdert 1984, Meunier et al 1984.…”

Clinical and experimental aspects of viral myocarditis

“…Disintegration of the cell is probably due to the combined effects of inhibition of macromolecular synthesis and accumulation of virus and structural proteins (115). In the experimental animal heart, myocytolysis is attended morphologically by coagulative cytoplasmic contraction and granularity, nuclear pyknosis, and cell fragmentation (54 (98), and picornaviruses in various species such as primates (79), hamsters, and rodents (21,71,73). The murine model of picornavirus-induced myocarditis is the most extensively studied.…”