The present stud} wa~ conducted rrom August 2004 to Apnl 2005 \\ L1h Iht: ObJccll\e~ IIf dctemumng. the prevalence, extent and d istribution 0 dourine III horses and IO\CSlIgaling occurrence of cllmeal cases 3S well 3S carner st:ltes of donkey .. and mules III the Arst- B:llc Illgh la nd s. At the same time a lon g Ltudmal study was conducted to assess the efficacy of the Isomet::mudlUlll chlonde ( IS MM ) Hnd D lITu nazenc acetumte (I)I~ I ) III Iht treatment of ch mcal c ases of dou rine. An IIlvcs ligalion was also conducted encom pa~Slllg cluesttonmure nnd serological survey o n th e presence of dO Urine in adjacent geograph ic"l areas of the Ar<;I- Ha1c highlands and other sclec ted parts o f the country with lugh equlOe population, The stud) methodol ogy was based on quest io nn:lIrc, serological. climeal and pa rasitologica l surve~, The questionnaire survey indi cated th ai do urine, locally known, as " Lappessa" or " D irr C$s a·· is a major health problem of equ ines in th e Arsi-Bale hi g hlands Though, dourine 1<; a common clinical case th rough Qut th e year, it has a seasonal character. \\ hieh most com monly occur" following Ih t' b reeding !;l' aSOIl from Junc to late Septembe r. SOIllC!ltne~ a <;('coml peak IS observcd III Ihe dl) seasons of the ~ car (Marc h to t>.<lay), which prob.lbly as~ocmted v,lIh relapse II I pre\ tOllsly Infecli:d and recovered cal;cs due 10 stressful \:ondlll o l1" of I('ed sh~rl a gc Of ('~9 hor .. ,: I;en! tested for the detection of ':l!ltibod ies agai nst T ~'Clllllh.,.dlllll. rc\calcd a scrnposlIl \ c .., f IS .. (28.35°;' ), 161 (24.81 % ) and 125 (19.26(1/0) for CA [1. L/\ rEX and I: LlSA !C~h. rcspcctl\'cl~ Ri sk factors with sigmfic ant association to douflne \\erc partly numbcr, pre\I011' history of abortion and body condlli o n sco rc . No try pa nosome,> o r any other haemopara~l1c~ could be detected in all cxanll ned Glemsa stained smears (th in blood. gell ital di sc harge and ti~l;uC fluids) as well as In bl ood samples by mil CT. All th e puppIes Inoc ulated \\lth blood samrk~. gellll.tl wa she s and oed cmalOUS nUids remained parasl1ologicall ) Ilegau\e. Diffe rent ch ara ctcri stic clinical signs o f dourinc were observed in clilllcally ~Ic k horses of both sexes . The prominent clinical signs observed as geni tal fo m) o f the di sease mclude vagmal dl:.chargc mallll~ of mucopurulent type "ilh foul odou r. oedema lind presence of deplgmcn ted ..,cars 0\ (' 1' till' o,:)'lerna l genita lia , oc,icmu o f Ihe <;cro ltlm and prepuce aecomp:llllcd by pn:pucl.:t1 ali \\ell .h urethral d Isch arge and ukl'rallon of the gen ita l m ucosae mlllnl~ nf the- pen tie In hoth "'C\l' ~ . lamencs~ in one or both leg ... panml dr;tgg ln g and slIffnc"s of thl' lund Icg~ and Itlcoordtnilth)n \H·r~· lhc dominant sig n .. nbscrv o.!d , I ~ nervous fo rm of lhe dl ~CIl<;C viii Horses with different ehOlc al signs of doun nl! were categonsed Into one of the followi ng fi\e grou[ls based on th e cl llll cal findin gs Apparc llIl y health y (46 81. non -s pccliic s ign s like ema ciat ion ilnd weakne ss (69); ge nital fonn (30); nervou, fonn 01 [15) and bo th gCTll1ul .lnd nervous forms of th e disease (67). Fifty - four horses with hi gh pCrtenl :l ge [lO !.I U\,II)' fOl the md lrec t anllbody ELI SA and mn eleen horses wllh stron g agglullnall un reactlOTlS having end III fe of 1.32 for both CA l-r and LATEX tes ts be longed to th e liw of th ... dlffeT1:nl dUlleal group~ ChI-sq uare analysIs of the di s tributi on of anImals. claSSIfied liS C) tl Wf POS III\ e llr negative 011 Ihe ba sis ofallthi." three teSt s. in th e clull eal grou ps demon st rat ed a s tat l<;tltally slgm fi cn nt d iffe ren ce between gro ups. with s tratum specific prevalence o f po siuvc amma i<; mc rca!'llllg wit h In crc aslIlg severity of clmieal sign .. (p<O .OOl). The concordance between (C ATT an d l:.LlSA) and (L A"' EX lind ELISA) test re sull s were 64.80% and 6960%, respec tivei) . rhe ... appa st; III SIlC between the les ts ind ica ted substa nt ial agreement where 125 sera tested pOS ltlVC and 435 "e ra tes ted negat ive in CATT and ELISA te sts and with 12 5 se ra tesled posi tive and .! 50 ., era tem'd negau\ e III LA TEX and I:LlSA ' est~ . A 10ngitudlll:J1 stud y was carried OUt to a~~\!~<; th e therapeutic actl\ 11> of I SM~1 and Dl:V1 III selected serologically po slI1\·e cli nical cases of Cou nnl.' 111 A<; as<;a dl !'llTh:l of th e Ar !') hlghl.lIlds A lot.11 of 24 adull 10e:11 horses were divided Inl O ~ group, of cq11al number I' CV k\ cl. eos!l1opllll cou nt , body temperature, se rologi cal sWt u". unrf\)\emcni of the C'I'tlllg clinical !'Ilgn~ Jnd bod) w ndition ~Cl)rc \\ en: moni tored tWIce m 10 d):" 1I1Ienal fClr a penod til 40 dll) ~ rhe res ults IIldu:ated th at mean ]l eV, eosinophil counts and t>"dy Icmperaturl' impw\ ed in bo th J S\ I~I and D I ~I treated group during th e 40 day s pO St tr(';ll meni penod A ~ Ia nsth:,ill ~ sig nifi can t Increase in PCV and body temperature was observed ~1.lrIlIIg frOlll th e day 10 ( P<O.OI) and a hIghly Signi ficant van anon ( 1' <0 .001) wa s observed al the cnd of the expenment The re W:l:. a mar ked unprovcmclU In th c cxi stlllg clinical Sign:. and h'd: (undma n score of Ih e study anl1nal s under th e IS MM and DIM groups as compared 10 control ;trHl11als withm the 40 days pOSt trcatme lll follow up lime . All Ih e st udy animal s remain ed ,erolog lcally posit IV," fO/ bOlh CATT and LA T EX tes ls Ihroughou t th e 40 da ys of the study Tll' nod The occurrence of act ive cltntcal cases of dourine in two donkeys as well as serological ~arncr ,taIeS In 11 donke y ... and 5 mule<; \.erc al so observed Sero logical as well as qu cslionn:m..: r-:l"e d 'llrVC )' ..:ondu cted LII V;ln OU5 represent atlv c S1le <, of Ilk' cou nt ry as to the occurrence of dllUrt!W re\ e ll led the prc <;(' Il( e oflh\! dl sea ' e III U rag:1 and Shashcllll'llC di stricts ufthe Ol'Ol11ly:l RCghl!\ ,Inu '\rbeguna distill! III th e SNNPRS (5mnhern ' allo ll , N:lti onallllcs and Pcople Reg ional 51,\11.'\ " I lus IS th e lirst report to establish the occurrcnce 01 dOUrine outside 01 the prc\lousl> kilO .... n ende mi C fOCI of the ArSI-Ualc hIghlands of I:thIOPI:l ,\llhough thcre wa~ no d,rect detection of T C'qU/f)('rdllfll, there IS 'mong eVidence Ihal dounne IS highly pre\:llclll, mo,t Important problem LIl th e Arsi- llaic hIghlands. whe re the Sllua tlon IS gellmg .... orse \\ Llh the preo;cOI spreading trend to areas previously known as free of the disease. neces,"alC~ urgent nall onal control intrevtion