Characterization of a causative agent of virus pneumonia of pigs (VPP)

Abstract

Signature was redacted for privacy.Signature was redacted for privacy.Signature was redacted for privacy. il TABLE OF CONTENTS Page SUMMARY 211 LITERATURE CITED 214 ACKNOWLEDGMENTS 228 susceptible pigs with material filtered through Gradocal mem branes of 0,8fj. APD, but not with 0,^6jx APD membrane fil trates, Macroscopic pneumonic lesions were present on the twelfth day postinoculation. Tney failed to propagate the infectious agent in the allantoic cavity or on the chorio allantoic membrane of embryonated hen's eggs, and they could not infect mice or ferrets with the agent. They recognized that their disease resembled the chronic pneumonia described by Fullar (1948, 1949a, 1949b) in Australia, and called tne disease by the name suggested by him, namely "Infectious Pneumonia of Pigs." The emphasis in this review will be on the attempts at propagation and characterization of the causative agent of virus pneumonia of pigs since excellent reviews by Betts (1953), Hjârre (1957), L'Ecuyer et al. (196I), L'Ecuyer (1962) and Young (1964a, 1964b) adequately cover the historical, geo graphic and economic aspects of the disease. L'Ecuyer (1962), in a very comprehensive review of the literature pertaining to pneumonia in swine, discussed the emergence of virus pneumonia of pigs as a recognizable entity, differing from swine influenza on clinical, pathological and etiological basis. He also presented a detailed discussion of the role of a number of bacterial species and Mycoplasma hyorhinls as primary or secondary pathogens in swine pneumonia.