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h ac a, N .Y . Ab stract. T hirty-two of 51 catt le infected with Mycobacterium paratub ercu los is ha dchro nic e nte riti s , chro nic lymp hangiti s o r me senter ic lym p hade no p a th y , or a ll three , at sla ug hte r. G ran ulom a tous inflammato ry le sion s were mi ld to a d va nce d a nd predominant ly invol ve d t he dista l sma ll in testi ne . Re ctal invo lveme nt wa s see n on ly in five ca tt le . Fourteen ha d microgran ulom as in the live r . There were t hree cytologica l form s o f macrop hage s : hist ioc ytic , po lygon al a nd e p it he lio id . T he la tt e r two types ha d engulfed mode rate num be rs of acid-fast b aci lli. T he h ist io cytic m acro p hages usua lly were packed with ac id-fast bacilli. Except in th e live r a nd occasiona lly its node s , remote le sio ns of para tubercu lo sis were no t found in ot her orga ns. One animal had endocardial a nd ao rt ic ca lcification s. Most catt le with sig ns of diarr hea ha d glo bule leu ko cytes in or around mye nteric ganglio n ce lls . T he thymus of 3-to 8-year-o ld catt le wit h clinical signs freq uent ly had mi ld to a d va nce d involut ion . T he th ym us of sim ila r ly aged infected a n ima ls without clin ica l signs, a nd of pa ratu be rc ulos is-nega tive animals , ha d no t involuted .Parat ube rc ulosis (Jo hne's disease ) , a chro nic infectio us disease of do mes ticated and wild rum inant s, has been recognized t hro ug ho ut the world since it first was descri bed in 1895 . Its ca usat ive agen t is Mycobacterium paratuberculosis, a faculta tive intracellul a r acid-fast bacte rium . T he macroscopic a nd hist ol ogic lesion s of pa ratubercul o sis basically remain confined to th e in tes ti ne , mesenteric and ileocaecall ymph nodes [7] . A lt ho ug h M . paratuberculosis has been cultured from a variety o f othe r orga ns , microscopic lesio ns have been found o nly in th e live r [1 2] . M . paratuberculosis is ass umed to sprea d prim a rily via circulati ng macrophages. In the liver th ese macro ph ages ma y become foca lly tra pped in sin usoi ds a nd with lymphocytes ma y give rise to micr ogr anulo mas .Early inves tiga tors of par atubercul osis e mp has ize d its similarity to leprosy [3 , 5 , 10] . Bo th diseases are ca use d by acid-fas t bacte ria th at a re diff icult to culture a nd hav e lon g gro wth periods . T he inflamm at o ry response in both d iseases is similar. Despite invo lveme nt of differe nt orga n syste ms, th e micro scopic lesion s a re dom inated by macr oph ages an d Lan gh an s' gia nt ce lls .Le prosy has bee n classified int o two po la r fo rms -tube rcul o id an d leprom at ou s 19 6

Two juvenile green turtles Chelonia rnydas with multiple cutaneous and ocular fibropapillomas were evaluated. Both turtles were anesthetized and fibropapillomas were surgically removed and examined by light microscopy. Turtle No. 1 died postsurgically and was necropsied. Turtle No. 2 recovered and was anesthetized 3 wk later to remove remaining fibropapillomas. Three weeks after the second surgery, Turtle No. 2 died and was necropsied. Histopathologic evaluation of hematoxylin and eosin stained sections of fibropapillomas of both turtles revealed areas of ballooning degeneration of epidermal cells associated with eosinophilic intranuclear inclusions. By electron microscopy, inclusions consisted of virus-like particles measuring 77 to 90 nm. Envelopment of these particles was observed at the nuclear membrane and mature enveloped particles measuring 110 to 120 nm were present in the cytoplasm. Based upon morphology, size, and location the particles were compatible with those of the family Herpetoviridae.