32 Table 3.1 Number and results f bld samples and adhesive tape swabs examined in dgs frm Bksburg Test Number tested Number psitive Percentage (%) Thin bld smears (Diff Quick) 132 1 (Babesia canis).8 Thick bld smears (Giemsa) 132 Bld filters 132 3 Dipetalnema 2.3 recnditum Adhesive tape swabs 148 3 Dipylidium 2. caninum 3 Taeniid 2 Txcara canis 2. 1.4
Table 3.2 Helminth species recvered frm 69 necrpsy exammatlons f dgs in Bksburg '---DatelDg I Ancylstma Ancylstma Txcara Txascaris Spircerca number caninum braziliense canis lenina lupi d' ~ d' d' ~ d' d' ~ 28/5/1997 2.2 28 33 1 3 1 28/511997 2.3 1 21 2 1 25/6/1997 3.1 26 42 1 2 25/611997 3.2 2 4 1 25/611997 3.3 3 7 25/611997 3.4 53 68 4 11 9/711997 Rl 51 75 2 2 9/711997 R2 3 1 9/7/1997 R3 3 6 4 3 Trichuris vulpis d' ~ Dipylidium caninum (scleces) 3 1 4 3 1 2 3/711997 4.1 3 1 3 3/7/1997 4.2 1 2 1 8 3/7/1997 4.3 53 95 6 3/7/1997 4.4 3 4 125 18 6 27/8/1997 5.1 27 42 1 2 4 14 27/811997 5.2 122 152 2 2 12 4 27/811997 5.3 37 44 1 15 28 16 11 27/8/1997 5.4 17 31 27/8/1997 5.5 16 2 2 7 1 16 27/811997 5.6 26 21 9 11 64 27/8/1997 5.7 47 89 9 3 6 2 27/8/1997 5.8 1 7 2 2 27/8/1997 5.9 165 223 35 8 27/811997 5.1 1 25 27/8/1997 5.11 1 1 22 27/8/1997 5.12 1 3 2 27/8/1997 5.13 3 7 31 111/1997 6.1 1 11111997 6.2 1 1 1 11 9 Jyeuxie/la Taenia spp. pascuajei (scleces) (scleces) OO~ 1 1 38 511111997 O() 511111997 511111997 7.3 1 3112/1997 8.1 1 2 32 I 311211997 8.2 28 36 1 39 3112/1997 8.3 3_11 3...~... O()_... 9 O_J w I w
Table 3.2 Helminth species recvered frm 69 necrpsy examinatins f dgs in Bksbur:J (cntinued) 311211997 8.4 39 48 7 9 1 311211997 8.5 4 6 13 1 3112/1997 8.6 3 8 2 3/12/1997 I 8.7 I 2 6 I 19 I 16 I 3/1211997 I 8.8 I 35 I 33 I I 11 I 1 I 3/1211997 I 8.9 I 45 I 53 I I 1 I 3 7/111998 I 9.1 I 52 I 5 I 23 7/111998 I 9.2 I 27 I 21 I 2 4 5 13 7/111998 I 9.3 I 44 I 57 I 7/111998 I 9.4 I I 48 I 42 I 7/111998 I 9.5 I 4 4 1 4 1 42 7/1/1998 3 29 7/111998 1 9 13 251211998 I 11.1 I 4 5 I 1 1 3 251211998 I 11.2 I 7 4 I 6 5 251211998 I 11.3 I 7 3 1 3 288 25/211998 I 11.4 I 623 I 977 I 6 7 251211998 2513/1998 1 Ttal 69 I 1944 I 2698 I 81 63 276 175 27 21 197 56 I 7 8 959 174 3 w...
38 Faecal fltatins: Faecal samples were cllected and the fltatin tests dne n 61 f the dgs euthanazed t cmpare with the helminths recvered frm the rgans. Distinguishing between the eggs f A. caninum and A. braziliense micrscpically is nt pssible. One fltatin shwed the presence f Ancylstma spp. eggs, but n Ancylstma spp. were recvered frm the rgans. The same phenmenn was seen with three T. canis psitive faecal samples. This culd pssibly be as a result f the dg ingesting nematde eggs and nt the infective larvae. The eggs, nt being infective yet, then pass harmlessly thrugh the intestine. Faecal egg cunts n carnivre faeces may be inaccurate (Miller, 1966), as the fibre and bulk cntent f the diet r the cnsistency f the faeces will influence the results. One may als argue that the number f eggs fund n fltatin nly reflect the ppulatin f patent Ancylstma spp. females present. The number f eggs prduced per female per day als varies as the duratin f the nematde infectin prgresses. A. braziliense females als prduce less eggs per day than d A. caninum females, and the presence f immature stages and the male : female rati f A. caninum will als influence the egg yield per gram faeces (Miller, 1966). It is still uncertain t what extent cncurrent infectin with ther species f nematdes and envirnmental factrs such as limited (dg) freedm t ram, re-infectin rate, nutritin, clinical disease, etc., will have n the faecal egg cunt. Necrpsy recvery: A. caninum: This was the mst cmmn helminth encuntered. The actual number f A. caninum as a fractin f the ttal Ancylstma spp. hkwrms recvered frm the
39 intestines at necrpsy is mre reliable as differentiatin between A. caninum and A. braziliense can nt be made by faecal fltatin. In this study area, 97% f all Ancylstma spp. recvered frm 61 infected dgs, i.e. a ttal f 4 642 hkwrms, were A. caninum. The fact remains that the incidence f A. caninum at the levels encuntered in Bksburg is a cause fr cncern. Only a few wners were aware f the pssibility f their dgs harburing internal parasites althugh sme (11 %) treat their dgs against wrms. A. braziliense: Althugh A. braziliense was less cmmn in dgs frm Bksburg (23% dgs infected with Ancylstma spp.), its mere presence in the cmmunity is significant. It des nt cause anaemia t the same extent and severity as seen with A. caninum, (Miller, 1967) but it is well knwn as a znsis that may cause cutaneus larval migrans in humans. As medical recrds were unavailable, the ccurrence f larval migratin in human patients culd nt be expressed in numbers fr that area. T. canis: This nematde was recvered frm 25 f 69 dgs. Fifteen (Le. mre than ne-fifth) f these dgs were infected with gravid females. These are prbably respnsible fr recntaminatin f the hme envirnment, and again culd pse a threat t public health, as this species is als zntic. These data als supprt the thery that T. canis favurs pups r immature dgs, bitches in late pregnancy and lactating bitches. Of the 25 dgs infected with T. canis, 17 were pups, tw subadults, tw lactating bitches, and nly fur were adults. The
4 reasn why these fur adult dgs harbured T canis is uncertain, but may be related t sub-clinical disease r recent recvery frm disease, nutritinal deficiencies, r stress-related relaxatin f immunity. Many dgs in these cmmunities are fed nly maize prridge, and ften ne may find that a lack f prtein may undermine the efficiency f the immune system. The number f wrms recvered frm the adult dgs was lw, tw t fur n average, except fr ne dg that had 1 adult T canis males in its small intestine. T lenina: The ccurrence f T lenina in the Bksburg study area is cnsiderably less than T canis. Only six dgs were infected. The mst recvered were 19 frm an apparently healthy dg. Anther dg had 16 adult T lenina in the small intestine, and this dgts immunity was clearly cmprmised as it was als suffering frm parvviral enteritis. The ther dgs infected carried an average fjust mre than three wrms each. S. lupi: This is a nematde fwhich the imprtance is greatly underestimated n bth prevalence and pathgenicity. S. lupi is diagnsed in the live dg nly when esphageal granulmas cause physical bstructin, r frm resulting secndary stesarcmas. On diagnsis, the cnditin is already far advanced (Harrus et ai., 1996), and the prgnsis is guarded. Sme fthese cases are misdiagnsed, as pacity f esphageal r artic granulmas nly shw up n x-ray film when calcificatin f lesins takes place. Oesphageal endscpy may shw granulmas, but this prcedure is seldm perfrmed n patients. Faecal fltatin and sedimentatin techniques are nt very effective fr the same reasn, and the sensitivity theref is questinable (Evans, 1983; Markvics and Medinski, 1996), as patent females have t be present t
42 Bksburg area, 44% dgs were hsts t this tapewnn, with up t 288 scleces recvered frm ne dg. The intennediate hst that transmits this tapewnn, the cmmn flea (Ctencephalides spp.), was present n many f the dgs that were infected. The presence f D. caninum In the dgs suggests that neither flea cntrl nr dewrming with a cestcide is being implemented. In a resurce-limited cmmunity such as this it is pssible t imagine that fleas and therefre als D. caninum wuld be abundant. The level f infectin with Jyeuxiella sp. (6%) was nly ne-seventh as high as D. caninum. T. hydatigena was present in 3 dgs. Althugh sme wners said that they treated their dgs regularly fr internal parasites, n significant change in the helminth results f the faecal fltatins f their dgs culd be demnstrated. Recmmendatins fr dg-wners in the Bksburg area: The mst practical cntrl measure t reduce the chance f transmissin f helminth parasites between dgs and frm dgs t humans is t prevent cntaminatin f the envirnment with infective eggs and larvae by regular remval f dg faeces frm the living area. Therefre, faeces shuld be picked up at least n a daily basis, and dispsed f by either thrwing it int a lng-drp tilet pit, burying r burning it. Regular municipal garbage dispsal may nt be the answer, as dgs ften ram the
43 area, knck ver garbage cans and scavenge fr fd, and may therefre becme infected. In the Bksburg area, bitches shuld be dewrmed befre breeding, shrtly befre and abut three weeks after whelping t reduce the transmissin f infective larvae t the pups in the milk. Taeniid and ascarid eggs may cling t the dg's cat, therefre the dg shuld als be washed. The cntrl f vermin such as mice and flies that can act as paratenic hsts shuld als be cnsidered. S. lupi, T. canis and T. lenina were identified frm necrpsy samples frm the Bksburg area, therefre dgs frm particularly semi-rural areas shuld be prevented frm eating dung beetles, frgs, mice, lizards r uncked chicken scraps. Flea cntrl using dips, pur-ns, flea pwders and flea cllars will als help prevent transmissin fd. caninum. Frm a public health pint f view, with many dg helminths being infectius als t humans, educatin in the cmmunity t ensure an understanding f the reasns fr intrducing new r different habits is called fr. Helminth larvae and eggs might be ingested by eating r placing hands in the muth r nt rinsing fresh vegetables befre eating. Children shuld avid playing where dgs have defaecated, and peple shuld prevent direct skin cntact with the sil, e.g., wearing shes especially in sandy areas. Small children ught t be prevented frm eating sil. There was a cnstant SPCA presence in the resurce-limited cmmunities f Bksburg. The residents knew the persnnel and c-perated with them. In additin t enfrcing animal health regulatins, the SPCA culd als extend their invlvement in the cmmunities by educating animal wners n parasite cntrl, either by prviding infrmatin during their daily visits in the areas, r by rganising infrmatin days.
44 Well-infrmed wners will als be aware f alternative pprtunities when seeking veterinary help. The cmmunities are situated clse t Bksburg twn, where veterinary advice and services are available. There are pprtunities fr future research prjects, and the cmmunities culd als benefit frm this as the animal wners nw knw that research will eventually imprve animal and cmmunity health and therefre serve fr the upliftment f living standards in the cmmunity.