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Pox-rirus itfectiort - this disease has been rec-orded in a number of countties (for
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-literature
tatf"* i"lgf 1991) and has been adequately desc bed lt was fiist confirmed in
zimbabwe in lgg2 ", and is now known to o" pr".int on t3 fu.ms. However this figure is likely
ili;;;;",i;;;;e"ouse. atrt'ougtt *otuiditv is vefv high mortalitv is Iow and specimens
are not submitted as fbrmers can eas y recognise the tiondition themselves The signific?rnce
iiri'"'a'i""."''.* li* in o" to"t tt'i it piedisposes !ne.skll.t9
m91e t*:i: tu:91^^",i1
tu"t".iut inu^ion, described below, which may prove fatal Trials with autogenous vacclne
have eiven variable iesults Unvacclnated individuals are likely to develop generalised pox
J-"nih" liu" uu".in" uirus is introduced into the reaing environment'
Chlarn\diosis - this is a recently recognised infection of crocodiles in Southern Africa
"ti ii.i&. i,. a., in pressl, ihough it has been described in othereptiles (Newcomer e''
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iit'itrcrogical specimens' demonstrated thathe inrection
"'*u*ioition
fr^ Ui* lr**, i'n Zimbabwe for some time an''l it his no* been diagnosed on 15 farms The
u.i ur -*ii""turion i. ucute hepatitis' often associated with adeno_virus infection Usually' there
'.pt""o
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tt " .nt" prevalence of asymptomati caniers is unknown'
Cn'Jmyoia lntiction may be a potential zoontrsis' but there is no evidence that crocodile farm
workers have been al'fected
6aierial disease - this remains the major cause of mortality trom intectious dhease in
t;;;". As previously reported (Foggin' 198?)' gran negative e erottacterraceae are
"*"Jry i"r"r""rl r.l*rotii enteritis. a pa'iiruiarlv devastating form of baclerial disease' often
follows adeno-virus lnlecllon or cocclqlosis Of most concem has been lhe high proponion of
infections with Salmonella spp., a group which has public health significance Over a four year
o"ri"ll oS,a?, ,f t*"rial isolateifrom crocodilesubmitted for post mortem were identified
!, iuitit"""ff" ,pp. wrtild salmonell arizonae is often isolated incidentally and may- almost be
;;;;; a normal intestinat bacteria of crocodiles, Group c salmonella and s2lmonella
iuirri.*i"rn
", *pable of acting as primary pathogens The practice of using poultry or
iiJ***
"pp*t which iay have diei from infectious disease, as a source of food
"".""ii", "i"iimnls
iJ"-.*"oir*, is likely ro have contributed to the increasing prevalence of infection by these
organisms,
Salmonella-contaminatedcrocodilemeatisunacceptableforhumanconsumption,yetclose
iJio67;'"i i..med crocodiles cary these bacteria (Madsen' pers' comm' ' 1992) and
ii"""iii" -ir"tp"i"a ""i..r, ,rtait woulo ue difriculto produce crocodile^meat free of these bacte'ia'
inii;. -ffisei
and Chambers (1991) found that 16'4% ,of tail-meat samples were
l'iiilr""iJ*rirt s"i.o*,lia, a ngut" d'at i" somewhat lower than the contamination raterfor
crocodiles in Australia (Manolis et al ' 1991)
co.ci.,io.'jJ-thisdiseasewasfiIstdiagnosedoncfocodi|efalmsinl9?8'thoughithadalmost
."""i,tf V- t*"- p*** betbre. lr h;.now beeo confirmed on 28 farms- Monality from
coccidiosis can still be very high. though it responds well to, treatmenl with
.
."tpi"""nf"apy.-f"". Undersize indiiiduals arJ most susciptible' and death is often a result
ofnecroticentelitis.Insevele'acutecases,shizontsandspo'ocystscansometimesbe
1".""a""a4 in liver, lung atd othel viscera Coccidiosis can also be a cause of runting
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natuie ofthe inflammation that may be produced in the biliary system'
ii*Ji" trt" "iii" r* "rti""r" trt", r"rmers are urged not to pulchase hatchlings from infected farms' unless
,r,r^l,'"i" .".",rJ ,i*rgrtt from the ;cubator' ; number of farms are infected every year by this
practrce.