Abstract
In Septembert 1964, two spontaneous cases of pox disease of swine were found amongpigs in Tottori Prefecture in Japan. They were examined rrnainly for pathologicalfindings of tlte sl<in.They were 3.5-month-old hybrids betvveen the Middle Yorkshire and Landracebreeds>consisting of a male and female. They had shovvn no clinical signs other thand3zspnea, which was observed just before death.Macroscopically, papules were present on the skin.Microscopicallyt thickening of the epidermis and vacuolar and reticuJar degencrattornof the prickle cells were observed in the damaged parts of the slain. In some papules, prickle cells corrtairned acidophilic inclusion bodies, and these cells of the deep layer ofthe epidermis sometimes slightly basophilic inclusion bodies, Both type of ine[ustonbodies were positive for PAS reaction, slightly positive and stained pale blue with Giernsastain, eale red with Gram stain>and nesative vviLh Sudan III stain. Furthermore, theprickle cells contained such nuclear vacuoles as observed in the case of infectnorn Withthe original swine p0X virus and as described by some authors. The eorium exhnaiteacongestion, hyperemia, edema, and cellular infiltratiotn with rneutrophtls, eosirtophils, amta[ympItocytes, and per"ivascuJar histioeytic proliferation. In the subcutis, thesechangeswere present, though they were milder than those in the coriurn. Sometimes, abscessformation, incrustation, ulceration, and regeneration were observed in the epiderrnis.In addition>localized parenchymatous myocardial degeneration, relatively severestagnation edema of the lungs, sometimes accompanied by hemorrhage, and such circu-latory disturbances in the central nervous system as hyperernia and stagnation x.vithoccasional slight hemorrhage were observed in both eases. Ulcer was fortned in the largeintestine of one case.No etiological investigation was carried out.
