A SURVEY OF SELECTED BACTERIOLOGICAL INFECTIONS OF THE CHACMA BABOON ' PAPIO URSINUS ' FROM THE KRUGER NATIONAL

An absence of bacterial pathogens and zoonosesemerged as the salient feature in a bacteriological survey ofchacma baboons from the Kruger National Park. Totals varyingfrom 100 to 178 baboons were assayed for salmonellosis, shigel-losis, tuberculosis, brucellosis and leptospirosis. It is conjecturedthat with Kruger National Park baboons, the abovementionedpathogens are not expected to complicate handling proceduresor experimentation, provided a clean or pathogen-free environment is maintained from the day of capture onwards.


Introduction
Within the rapidly expanding literature on primatology, the baboon (Papio -.pp.) has always featured prominently (Shilling, 1964). This interest has further expanded to include the world of medicine, where the use of Papio spp. as model in biomedical research has been generally acclaimed (Vagtborg, 1965). In South Africa this was borne out by successfully exploiting the large numbers of baboons which are found in certain areas of the Republic for experimental purposes. Research projects on surgery, serology, chemistry, pharmacology, neurology, radioisotopes and specific disease conditions such as nephrocalcinosis, artherosclerosis and cancer have found ideal research material in the baboon (Baboons in Organ Transplantation, 1968;Groenewald, 1970;De Klerk, pets. comm.) and are steadily exerting an increasing demand on the free-living baboon reserves of the country. In this respect the Kruger National Park (K.N.P.) have contributed handsomely towards the demand in the Transvaal and have sacrificed 370 to biomedical research projects over the years 1969 to 1970 as part of a discriminative cropping scheme. These baboons were taken mainly from traps near the vicinity of rest camps and along tourist roads bordering riverine areas where e,'--ssively high numbers of baboons are founitd aind Nwherehc inccisacncc vadlue of' indiividualis is atl timeis rarvd as % crv It igl. la li lch iii ci ii, vatigitt and( i15c( illt p cx i titi' n ts. wa is divhri-cfbo ft~iteci %%itli a1 history of, conttact or sciiii-co)ntiit \\iti iloan b\V itwafý of* ui ca ut It( )isc' I tic (I ig proce-dl i cs by tour0ist SI (I t hc fret' lC((('5 to 4)flial (htiitps nlcm-i rest taiiiiis Fig. I U ,. I0 I I a 11(1 iis fron it re imt('s'il at sc' ini (s 0--o14ugit oit itt-1K. N. P. \c're uised. As part otf' this IsStutd\ it \\ as t hEtghi ad visabhie to asse'ss lt( h bacterioclogic(a t statius of' tltc baboons. However. i't'i rring to bacteriological aspects oi' rcr'i al allot iatnspi aitat aii o rt ioni (1tlttIra tisplatitlatiori w\it bi abhcoons as i'Xp ('iiciti(ttal mterttiai~l. iiredi( and NfttrphN 196~8 dtclared:i Distilictictr between''t infi-ctiin andi (isra~su is (d par.imtotttlt interc'st ito the transplant researchit iocrker. Bacteriotoggical finidings should be interpreted -with great caltitici. 'Ilii' tttc'r fact that at given mitcruobe is cuitutcCI from t pa itienit or hI'-ul all 4'xhprilitcutttil animali~t may-bc totatlly irrelevant. Only the( toitti-nation o)1 all phvNsical signs and of' all laboratory findings enabl)es all integra~tlted aill o' spec'ialists 14) (.outie to apprprtjiaiite (tIIfLIOSif~lS". After sima iii g tilitbac nwrob g cai sitrvev on an In tensivxe a rid( ambhitiouIs wcale this argumenitt \\ as realized and thte stud\, procedure miodified to inc lud e onfly tili-betterknoiwn pathot genis, part i C U a ill t hose Suspected of, being zootloses. Tbis report documents the results and conclusions of' this survey.
'i'hle traps were set up only in areas known to lbe frequented by baboons. like omf ]a clumrps fioni the rest camps and along rivecrine tourist roads, Drug imm11obilization techniques were auttempied along iloads which arc heavily utilized by' tourist traffic. Fruit and bread-crumbs \\ere used to entice tilt baboons towards the vehicle from which the darting \\as attempted. 'fhis niethod not only assured d ie selective removal of' "beggars" fromt the( community but greatly increased the probabilitN of' using baboons withi previous histories of' scrtni-contact with humans. TIhe (lamlt Isyr-inge was pr opelled by mneans of the "cap chur'" pistol Palmer, whlich was mostly catmouflaged by at paptr hag, therefore simulatif t~ abag ()I if go)ilies" to the beggar baboons. Immobilization wais eflleted by the use' of' Sernylan (phenevyl idine hivdrochloride, "Parke-Davis and Colnpan v-, tite subjects retrieved and then taken directly to Sku kuza wlic.
tt..were kept for at period not exceeding five clays prior to tite cotmtiencement of' necropsy procedures. During this period the\. were kept -ii separate cages and fe-d inecalie porridge, oflh'l fruit and vege~tables from11 thet Skukuza rest camp restaurant. TIhe baboons from the capttire cages were also sedated wvith Sernylan in order to facilitate handling. While still recuimbent at razor blade was used to r, tmove the hair Fronm at threc cm square patch of' skin on the foreartm of the individual and 7500 International Units of' tuberculin 'Onderstepoort mianuflsctured wvere injected intradermally. In addition 3 5(10 LU. osf ttiberculin w\ere injected intto the upper eyelid. Animials w\ere kept under observation Ror three days lh~r signs of'a reactio~n, Such ats swelling and hypeiaemia. On the (lay' of examination the subject was again sedated, weighed and at throat swab taken before it wýas killed by exsanguinittion. Due to ctomphications (see below) the swab-taking ptocedure %\ais discontinued after I1) baboons were done. As soon ats dleath intervened, at very thoroughl and meticulously applied necropsy procedure w\is performed in each case. Relevant data and material were collected rotutinely as part of the surve\-. D~irectly on opening the gut, scrap~ings (approximately 2 g) from the wall of' the( small intestine (proximal tone fhmirth) and its contents, were suispendled in selenitt enrichtnent mnedium ( Oxoid . AXfter 6 hotirs incut-bation at 37'C a loopfull was plated on MacConkey agar, brilliant green agar, desoxycholate agar and Salinonella-Shigeila (SS) agar plates (Oxoid). All plates were examined after 24 hours of incubation at 37'C and non-lactose fermenting colonies tesembling Salm,,nella spp. and Shigella spp. were selected, and transferred to triple sugar iron agar (TSI) slants (Oxoid). Organisms giving positive and suspicious reactions (Bailey and Scott, 1966) were tested for motility and examined by the slide agglutination test with group specific Salmonella typing sera (Onderstepoort manufactured). Organisms reacting with the aitisera and nonmotile organisms were subsequently assayed for indol, methyl red, Voges Proskauer and citrate (IMViC) reactions (Bailey and Scott, 1966) and tested on carbohydrate media (dextrose, maltose, dulcitol, lactose, sucrose, inositol, salicin, trehalose, rhamnose, mannite, mannose). Isolates giving typical reactions were forwarded for serotyping to the Veterinary Research Institute at Onderstepoort, Pretoria, Transvaal.
In a.ddition to material from the small intestine, rectal swabs were taken from 20 baboons and treated in basically the same way.
During exsanguination blood was collected, the serum harvested and tested for Brucella and Leptospira antibodies. The standard agglutination tests as outlined by the joint FAO/WHO Expert Committee on Brucellosis (1964) wa, ised for the detection of Brucella antibodies. Standard Brucella abortus awiigi-n (Onderstepoort manufactured) was used. In addition to the 100 samples forming the main body of the study, this survey was supplemented by 78 incidental collections from the vicinities of the Skukuza and Lower Sabie rest camps. Sera were examined for leptospiral antibodies, employing the agglutination-lysis test, based on the standard procedure used in laboratories -.hroughout the world (Wolff, 1954) and which is considered a reference test (Roth, 1971). Five serotypes were used viz. Leptospira icterohaemorrhagiae, L. canicola, L. pomona, L. hyos and L. bratislava. A total of 130 serum samples was tested, consisting of 85 from the main body of study and 45 incidental collections from the vicinities of the Skukuza and Lower Sabie rest camps.

Results
An analysis by age and sex of the baboons that were incorporated in the main study, are provided by Table 1.
The throat swab material invariably caused overgrowth of the media by Proteus or fungus spp. Howev-er, in spite of overgrowth, a variety of at least 1bur different, but unidentified, organisms (colony morphology) were counted each time.
No Shhgellae sp. was isolated and only one Salmonella sp. was found, which was subsequently identified by the Veterinary Research Institute at Onderstepoort as belonging to the non-pathogenic soil group of Salmonellac. Further identification was not attempted.
The tuberculin tests as well as the Bruce/la and Lepiospira serological tests produced negative results in all cases. The complete negativcness of the inquiry was borne out further, during necropsy procedures, by an inability to find any pathological lesion which was caused or complicated by a bacterial agent.

General Bacteriology
Due to time limits posed by the comprehensiveness of the entire master study programme, the time could not be found to isolate and identify the multitude of species which apparently were associated with the mouth and throat environment. SN%.-rming Proteus and ove"rgrowth by fungi further toinplicatcd matters. I i,:s part of the study was, therefore, discontinued after 10 specimens were completed. However, in light of findings by Brede and Murphy (1968) to the efft-ct that baboons from tht Western Cape area exhibit an astonishing 54,1 per cent incidence ofStaphyilococcus aureus organisms in the mouth cavity, future inquiry into this aspect is indicated for the K.N.P.

Enteric Pathogens
Amongst non-human primates the trend of the literature seems to suggest at common incidence of enteric bacterial pathogens in newly imported as well as laboratory-conditioned primates 'Schneider, Prather, I.ewis, Scatterday and Hardy, 1960;Carpenter at. ' '2,ooke, 1965;Good, May and Kawatomari, 1969), whilst their countezparts in the free-living s;tate persistently failed to reveal the presence of enteric pathogens (Panda and Gupta, 1964;Carpenter and Cooke, 1965;Nath, Shirvastov, Sethi and Singh, 1966;Carpenter, 1968). Carpenter (1968) quotes surveys of wild primates from Tanganyika, Kenya, East Africa, Malaya and India which resulted in negative isolates from 827 animals examined.
Iml.41l)t). TIhis uxiduncc %%as introdoucd throuigh the fiitcl that no signs o) lit'est infi'ctjoiis; X\CIT4 i14)tvt iI 78 b~aboons ifrom thu K .N.P. \%ishii have' so tar. hu(.tt hcld I iiitp6ixit b\ thu NcudjuAl RtCsvm-ch CouncltI, (:.S.I.R., Prumoria D)c Kiurk, /wr,. eflm .i lhusu b~aboo4ns 4' at tilili's" Subjcuted to g atu us i 11( ti n il iht a lit t In \ariious cXp3crilfliclts. btit \I 'II ahI a is kvpt midu i ii inpccuuc4)1i h 'y cic hi gi'n i' conditiouns. It can rhurfn-10u b)c cotncilude that with K .\.1. babtoions ci'ituric patlo~gens aru( Itoi) 60 ba oo s n ll-l--il ýtl \ it(.co lsde ta si nil71 therefore expect that the sociable intratroop interactions would allow for a high degree of communicability of bacterial organisms within a group, whilst intertroop aggression would act as a limiting factor to the spread of disease to neighbouring groups. A representative sample of the population would therefore necessarily call for the exploitation of as many groups as possible. For this survey samples were taken from at least 29 troops and distributed throughout the study area. The chief rainfall and distinct vegetational areas were represented in the final selection of the troops. Results obtained in the study can therefore be expected to reflect the true prevalence of the assayed disease conditions for the total population. When not unduly disturbed, baboons do not live in ftar of human prc, ximi t y, ýind may eve-' he me|racted by human activity. Commenting on the preferred sleeping sites of a baboon troop, Stoltz and Saavman (1970) wrote: "Disturbance by humans seemed, however, to be of minor significance since the preferred sleeping site was situated where disturbance due to holiday-makers was most likely". In the K.N.P. the highest densities of baboons are most decidedly found along the tourist travelling routes and in the vicinity of human habitations. It must be stressed, however, that a high percentage of these roads is situatecd l' *.,• vicinity of watering points. This affinity to human dwellings is brought about mainly by the scavenging habits of the baboon. It is a habit which is quickly acquired, as is reflected by the promptness with which activity appears and assumes a habitual nature around temporary camping sites. in the free-ranging state as found in the K.N.P., favourable circumstances are therefore created for a zoonotic nidus, with the likelihood of the chain of inter-species infections being directed towards the baboon. The literature and the results of this study are, however, in agreement that an exceptionally low incidence of bacterial zoonoses are found in free-ranging animals. This can only point to an efficient disease cleansing action on a population or community level under extensive free-ranging conditions, but which can be broken down by artificial and essentially intensive conditions as posed by captivity.