Exudative Epidermitis in Pigs:Etiological Studies and Pathology

by C. L'Ecuyer and K. Jericho*.

SUMMARY

The experimental production of exudativeepidermitis of pigs following the inoculationof skin scrapings or cultures from field orexperimentally-produced cases of the diseaseis described. Typical lesions of exudative epi-dermitis were produced following inoculation,either intravenously or by scarification, ofbroth cultures of 4 strains of a micrococcusisolated from field cases of the disease. Theexperimental inoculation of pigs with skinscrapings sterilized by filtration or antibiotictreated, yielded negative results. Cultures ofCORYNEBACTERIUM PYOGENES and ofSTREPTOCOCCUS SP. also isolated from theaffected pigs, likewise yielded negative re-sults on experimental inoculation of pigs. Theconclusion is drawn, that the micrococcus isol-ated from field cases and which produced thedisease experimentally is the primary etiol-ogical agent of exudative epidermitis asseen in weaned pigs in this area. The histo-pathology of the experimentally produced di-sease is described.

SOMMAIREL'epidermite exudative a ete reproduite de

faion experimentale par l'inoculation a desporcs sains, de grattages de peau ou de cul-tures bacteriologiques provenant de cas clini-ques ou experimentaux de la maladie. On areproduit les lesions typiques de la maladie

*Animal Diseases Research Institute, Animal PathologyDivision, Health of Animals Branch, Canada Depart-ment of Agriculture, 100 Gamelin Blvd., Hull, Quebec.

par l'inoculation, par voie intraveineuse ou parscarification, de 4 souches d'un micrococcusisole de cas cliniques. Des grattages de peau,sterelises par filtration ou traites aux anti-biotiques ne produirent pas la maladie chezdes porcs d'experience. Des cultures de CORY-NEBACTERIUM PYOGENES et de STREP-TOCOCCUS SP. isolees 'a partir de cas cliniquesdonnerent egalement des resultats negatifs.On a tire la conclusion que le micrococcus encause etait l'agent etiologique primaire del'epidermite exudative telle que vue chez desporcs sevres dans notre region. L'on decritl'histopathologie de la maladie produite chezles porcs de fason experimentale.

Introduction and reviewof the literatureExudative epidermitis is an inflamma-

tory skin disease of young pigs, character-ized by the formation, over all or part ofthe body, of a thick, greasy, odorous, red-brown exudate. Morbidity is variable. Thedisease is serious in suckling pigs whereit produces a high mortality rate in af-fected litters. It may be more or less severein pigs up to 10 weeks of age and mortalityis dependent on age and the secondary in-fecting agents present.

Jones (1) reviewed the literature onswine skin diseases resembling exudativeepidermitis (greasy pig disease). He dis-cussed the various possible causes of thecondition (2) and speculated on the impor-tance of various bacteria, or bacteria andvirus combinations. He felt some coccimight be involved although only non-patho-

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genic species could be recovered fromclinical cases. Ristic et al (3) could nottransmit the condition to pigs by contact orexperimental exposure. Terpstra and Ak-kermans (4) concluded that "dermatitiscrustosa" was not specifically contagiousbut was due to a lowering of the resistanceof affected pigs plus other unspecified fac-tors.

Sandbu (5) concluded that "impetigocontagiosa suis" occured primarily in vita-min-A deficient pigs. He could transmit thedisease only in deficient pigs and the di-sease was quickly cured by vitamin-A sup-plements in the diet. Behrens (6) couldfind no causal relationship between exuda-tive epidermitis and vitamin-A deficiencyin piglets. Imai et al (7) recovered Asper-gillus sp. from most cases of papular der-matitis. They produced an atypical derma-titis by inoculating a spore suspension ofAspergillus into the skin of 3 pigs. Hanson(8) drew a parallel between exudativeepidermitis and parakeratosis in swine. Hestressed the similarity of the histologicallesions in pigs suffering from both condi-tions. He concluded that the diseases weresimilar and were due to a dietary deficiencyin essential fatty acids. L'Ecuyer (9)described 4 outbreaks of exudative epider-mitis in weaned pigs. He transmitted thedisease by contact exposure and could thentransmit it serially in pigs. Bacteriologicalstudies were inconclusive but he felt thatthe disease was clearly infectious in nature.

Hjarre (10) described impetigo conta-giosa as a rapidly developing, mild diseaseof piglets. He could reproduce the diseasein piglets with pyogenic cocci isolated fromskin lesions in clinical cases. Sompolinsky(11) reproduced "impetigo contagiosa" inpigs 8 weeks of age or older by contact ex-posure or by intracutaneous inoculation ofground skin from infected pigs. He recover-ered a non-hemolytic, white, micrococcuswhich produced typical skin lesions in 90%and death in 30% of the inoculated pigs.This micrococcus gave negative coagulaseand hyaluronidase reactions and could bedifferentiated from Micrococcus epider-midis by: (1) pathogenicity for pigs; (2)rapid and complete liquefaction of gelatin;and (3) inability to ferment maltose. Som-polinsky (12) proposed the species nameMicrococcus hyicus for this organism.

Underdahl et al (13) transmitted exu-dative epidermitis through 11 passages incolostrum-deprived piglets. They produced

mild to severe lesions with seitz 1.0 and0.5 micron filtrates and only mild lesionswith 0.1 micron filtrates. They postulatedthat the filtrable agent produced the pri-mary vesicular lesion and that secondaryinvading bacteria were responsible for thesevere generalized disease. More recentlyUnderdahl et al, (14) have made 5 isola-tions of staphylococci from outbreaks inNebraska. Four of these isolates were usedto reproduce the disease in colostrum-deprived piglets by intranasal-oral, sub-cutaneous or contact exposure. They feltnevertheless that a filtrable organism wasof importance in the production of the di-sease and that the staphylococcal organismswere responsible for producing the severeforms.The histopathology of exudative epider-

mitis has been studied by Jones (1), Som-polinsky (11) and Hjarre (10). Essentiallythe lesions they described in acute exuda-tive epidermitis were: hyperkeratosis,acanthosis with multiplication and length-ening of the interpapillary pegs, edema andhydropic degeneration of the superficialepidermal layers leading to vesiculationand pustule formation with invasion of theepidermis by neutrophils, involvement ofthe hair follicles, and congestion of theblood vessels in the dermis. Later the in-flammatory process involved the entireepidermis, with ulceration, particularlyaround the hair follicles, invasion of thedermis by neutrophils, eosinophils andmonoculear leucocytes. Mild forms showedsimilar but less severe lesions with exten-sive epidermal hyperplasia and invasion ofthe dermis by mononuclear leucocytes.Materials and methods

Pigs employed in transmission trialswere from 3 to 8 weeks of age and werefrom a minimal-disease herd maintainedunder strict quarantine. This herd had beenestablished with pigs obtained by Ceasariansection and raised in isolation withoutcolostrum. The pigs used were naturallyfarrowed and raised, they were weaned at3 to 4 weeks of age. During the course ofthe experiments the pigs were fed propri-etary rations.

Intravenous inoculations were done viathe ear vein. Scarifications were carriedout by shaving an area in the flank andlower abdomen, then criss-crossing it withthe edge of a scalpel point and rubbing oneto 2 cc of inoculum into the scarified area.

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TABLE I. Results in experimentally inoculated pigs

Inoculum Treatment Route' No. Pigs Results2

2601 Skin scrapings3 Antibiotics6 SCN 2 +2601 Skin scrapings Antibiotics6 IV 1 + + + +2605 Skin scrapings4 Antibiotics7 SCN & IV 33209 Lymph node5 Antibiotics7 SCN & IV 23209 Skin scrapings SCN & IV 3 ++2605 Skin Scrapings Selas 02 filtrate SCN 22605 Skin scrapings MP .45 micron filt. SCN & IV 22605 Skin scrapings ............ SCN 2 ++++C. pyogenes ............ SCN & IV 4Streptococcus sp. ............ SCN & IV 3Streptococcus sp. ............ IV 3Herd E skin scrapings ............ SCN 2 ++++Herd F skin scrapings ............ SCN 2 + + + +

1- SCN = scarification; IV = intravenous2 - + = focal reaction; ++ = mild extension; ++ + = moderate extension; and+ + + + =

generalized exudation.3 -First contact passage pig, Herd A (9), skin scrapings.4 -Second contact passage pig, Herd A.5 -Pig infected by intravenous inoculation of treated scrapings from pig 2601.6 - Suspension treated for one hour with 2,000 units penicillin, 2,000 micrograms streptomycin, 250

units mycostatin per ml. Inoculum was not sterile.7 - Suspension treated for 3 hours with 4,000 units penicillin, 4,000 micrograms streptomycin, 1,000

micrograms erythromycin, and 2,000 micrograms aureomycin per ml. Inoculum was sterile.

Bacteriological examinations were car-ried out by inoculating suspensions of skinscrapings or tissue onto bovine blood agarplates. Routine bacteriological procedureswere then applied for identification. Theinocula used, were collected from field casesof exudative epidermitis or from experi-mentally produced cases following contactor parenteral exposure. Scrapings and tis-sues were ground as a 1/10 suspension in aphosphate buffer solution or in nutrientbroth. Infectious suspensions were treatedas indicated with antibiotics for one to 3hours followed by light centrifugation. Fil-trations were carried out through micro-porous porcelain filters1 of maximum poresize of 0.85 microns using negative pres-sure or through cellulose membrane filters2of average pore diameter of 0.45 micronsusing positive pressure. All filtrates wereexamined for sterility by inoculation ontoblood agar plates.

Experimental results7Transmission Trials

Table I, summarizes the results of ex-perimental inoculation of pigs with skinscrapings, tissues or bacteria from fieldand experimentally produced cases of exu-dative epidermitis. Typical lesions wereproduced in pigs by the inoculation of un-

1. Selas Filters.2. Millipore Filter Corporation, Bedford, Massachusetts.

treated skin scraping from pigs in herdsE and F and from experimentally infectedpigs 2605 and 3209. Typical lesions werealso produced with skin scrapings from pig2601 after treatment with antibiotics.However, the suspension used for this in-oculation had not been rendered sterile asindicated by subsequent culture. The in-oculation of scrapings or tissue suspen-sions sterilized by antibiotic treatment orby filtration gave in every case a negativeresult. Furthermore cultures of C. pyogenesisolated from herd A and of beta-hemolyticstreptococci isolated from herds B and Dgave negative results when inoculated intopigs.The pigs were inoculated by scarification

or intravenously and the extent of lesionsproduced, varied according to the inoculumused, the route of inoculation, and the in-dividual pig. In pigs inoculated by scari-fication, positive reactions were character-ized by the formation within 24 hours ofhyperemic welts along the scratch marks.Vesicle formation in a narrow line alongthe crest of the welts occurred quickly andwas followed by pustule formation with-in 48 hours of inoculation. The white,raised pustules were easily removed if thearea was rubbed. Typical brown scabs wereformed along the scratch marks and thelesions became confluent to involve the en-tire scarified area. Generalization occurredslowly by extension from the scarifiedareas, however, in most cases little or no

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TABLE II. Results of experimental inoculation of micrococci isolated from field or contacttransmission cases

Herd Strain No. Rouet1 No. of Pigs Age (weeks) Results2 Reisolation

A 7 IV 1 5 ++++ +A 7 SCN 2 5 ++ +B 123 IV & SCN 3 5 -B 14 IV & SCN 2 8 -B 4 IV & SCN 2 8 -

B 3 IV&SCN 2 5 -D 21 IV 1 5 -D 21 SCN 1 5 + ....

D 21 IV 2 3.5 ++++ +D 21 SCN 1 3.5 ++++ +E 19 IV 1 8 ++++ +E 19 SCN 1 8 ++ ....

F 20 IV 1 5 -F 20 SCN 1 5 +++ +

1. - IV = intravenous: SCN = scarification.2. -++++ = generalized skin lesions; + ++ = extensive lesions over many parts; ++ = mild

extension; and + = focal exudation.3. - Three other biochemically identical strains from Herd B were similarly inoculated with negative

results.generalization followed inoculation by sca-rification.

After intravenous inoculation there wasusually a mild rise in temperature andgeneral signs such as loss of appetite, roughhair coat, and stiffness. This appeared inone to 3 days and the pigs remained ap-parently normal until the fifth day post-inoculation (PI) at which time, red, raisedfoci covered with pustules, developed onthe lower abdomen and thorax. These fociquickly became covered with the typicalbrown, greasy exudate and the lesionsspread over the ventral surface of the bodyonto the sides, head, ears and lower legs.At necropsy, usually on the seventh or

eighth day PI, the lesions showed varyingdegrees of generalization. Internally, no le-sions were found except for a serous or oc-casionally purulent polyarthritis in somecases, and enlarged, moist superficiallymph nodes. One pig, No. 3209, inoculatedintravenously with scrapings from pig No.2601, showed signs of posterior paralysisin addition to severe exudative epidermitisand at necropsy was found to have an ab-cess in the lumbar spinal canal. The 2 pigsinoculated intravenously with a culture ofC. pyogenes isolated from herd A had apurulent polyarthritis at necropsy. In pigsinoculated by scarification with non-infec-tious suspensions, narrow, raised welts ap-peared along the scratch marks. Thesewelts developed a thin, narrow brown scabbut both reddened welt and scab had disap-peared by 6 or 7 days PI.

Table II. summarizes the results of theinoculation of pigs with various micrococ-

cus cultures isolated from field or contacttransmission cases. Four of the 11 strainsused, produced typical lesions in experi-mentally infected pigs. The lesions variedconsiderably in severity from one strainto another and according to the route ofinoculation. Three of the four strainscaused lesions when inoculated either in-travenously or by scarification. One straininduced lesions only on scarification.Strains No. 7, 19 and 21 produced a gener-alized form of the disease with foci of exu-dation over the entire body, (Fig. 1). Therewas involvement of the hoofs in the pigswhich received strain 21 either by scari-fication or intravenously. The diseasewhich followed the inoculation of strainsNo. 7 and 20 by scarification was onlymoderately extensive. Micrococcus organ-isms apparently identical to those used,were re-isolated from the experimentallyinoculated pigs in each instance whereisolation was attempted.

Seven of the strains did not cause clinic-al disease in the inoculated pigs; theseinoculations were usually carried out inparallel with those of some pathogenicstrains and frequently were in littermates.The age of the pigs at time of inoculationand the concentration of the inoculated bac-terial suspension seemed to be of some im-portance in obtaining positive transmis-sions. Strain 21, isolated from Herd D,gave negative results following intravenousinoculation and only mild focal lesions byscarification when a light suspension ofthe organism was used in pigs 5 weeks ofage. When this strain was repropagated in

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Fig. 1. Experimentally produced lesions of exudativeepidermitis following intravenous inoculation of abroth culture of a micrococcus isolated from a fieldcase of the disease.

an enriched broth which provided a muchheavier suspension and inoculation was car-ried out in pigs 3.5 weeks old, severe le-sions followed inoculation by both routes.The incubation period, the course of the

disease, the evolution of the lesions wereidentical to those seen in the disease whichfollowed inoculation by the irntravenousroute or by scarification of skin scrapingsuspensions from field or experimentalcases. At necropsy, aside from the more orless extensive skin lesions, there was en-largement and edema in the superficiallymph nodes and mild serous polyarthritisbut no synovial membrane reaction. Theviscera and cavities appeared normal.

Clinical PathologyA group of 6 pigs aged 4 weeks, were ex-

posed by pen contact to 2 infected pigs.Two littermates were housed separately asnegative controls. Temperatures were takendaily from time of exposure and bloodsamples were collected by cardiac puncture,every second day starting on the day of ex-posure.Average daily temperatures of the in-

fected group were slightly raised (0.5 to1.00 F) in comparison to the control group,

from the fourth day to the twelfth day postexposure (PE). Average total white bloodcell counts of the infected group wereslightly higher than those of the controlsfrom the fourth day PE through to the con-clusion of the experiment. Neutrophils pre-dominated after the sixth day PE and ju-venile forms became predominant as thedisease progressed. The lesions in the ex-posed pigs were mild, with foci of exuda-tion scattered over the head, neck and body.The lesions never became confluent and nonew foci developed after the tenth day PE.The control pigs remained free of lesions.Necropsy examination of the infected andcontrol pigs, failed to reveal any viscerallesions.

BacteriologyThe 4 micrococcus strains isolated from

the field outbreaks were small Gram-posi-tive cocci often arranged in twos, shortchains of 4 or 5 cocci or as irregular pack-ets. The cultivation of the 4 strains onbovine blood-agar yielded white, opaque,slightly convex, non-hemolytic colonies withentire edges. All 4 strains produced acidbut no gas from lactose, glucose, andsucrose. No acid was formed in the pre-sence of maltose, manitol or salicin. Hy-

Fig. 2. Pustule formation with early epidermal hyper-plasia, dermal congestion, and migration of neutrophils.H. & E. X 210.

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Fig. 3. Hyperkeratosis with neutrophilic infiltration,acanthosis with the formation of long and compoundinterpapillary pegs, congestion and infiltration of thedermis. H. & E. X 100

drogen sulfide or indol were not producedand nitrates were not reduced to nitrites.Litmus milk was acidified and partiallyreduced within 18 hours of inoculation,coagulation occurred between 24 and 48hours and digestion had begun to occur by72 hours but was only partial after 7 daysof incubation. Gelatinase was formed by allstrains with complete liquefaction occurringbetween the second and seventh day of in-cubation. Although these data are insuf-ficient to properly classify these organismsthey would appear to be similar to Micro-coccus hyicus (Sompolinsky).

Histopa,thologyThe histopathology of experimentally

produced exudative epidermitis presenteda fairly uniform picture regardless ofsource of inoculum or of method of inocula-tion. There were variations in the severityof lesions from pig to pig and from onesite to another on individual pigs. Earlylesions (Fig. 2) were characterized by:mild hyperplasia of the stratum corneum,as indicated by the presence of flattenedcells with elongated nuclei and hyaline,eosinophilic cytoplasm; invasion of the deeplayers of the stratum corneum and the su-

g: .& .. ., _ -

Fig. 4. Microcolonies of coccoid bacteria in the super-ficial hyalinized layers of the stratum corneum. H. & E.X 700

perficial layers of the stratum germina-tivum by neutrophils, leading to pustuleformation; hydropic degeneration of cellsin the superficial layers of the stratum ger-minativum; acanthosis and lengthening ofthe interpapillary pegs; marked congestionof the papillary vessels of the dermis; andinfiltration of the dermis with neutrophilsand eosinophils.As the lesions progressed (Fig. 3), hy-

perplasia of the stratum corneum becamepronounced with massive infiltration byneutrophils and hyaline degeneration of thesuperficial layers. The superficial hyalini-zed zone was found to contain numerousmicrocolonies of coccoid organisms (Fig.4). Acanthosis was marked and frequentmitotic figures were seen in the germinallayer. The hair follicles were regularly in-volved and seemed to represent the site ofthe original lesions. The epidermal and der-mal lesions involving the follicles were sim-ilar to those described above, with a morepronounced neutrophilic invasion of theepidermis and the presence of colonies ofbacteria around the hair shafts.

In severe cases (Fig. 5), the epidermiswas 6 to 7 times normal thickness for thearea involved. The stratum corneum becamea thick, necrotic, hyaline layer, containing

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Fig. 5. Severe lesion of exudative epidermitis showing:thickening and hyaline degeneration of the stratumcorneum with infiltration of neutrophils, abscessationof the hair follicle, degeneration and ulceration of thestratum germinativum, and invasion of the dermis.H. & E. X 100

neutrophils at all stages of degeneration.Colonies of coccoid bacteria were frequen-tly seen near the surface and throughoutthe necrotic layers. Microabscesses werealso seen. The stratum germinativum wasdisorganized with islands of cells extendinginto the exudate, hydropic degeneration ofcells in the superficial layers, numerousmigrating neutrophils, hyperplasia of theinterpapillary pegs and frequent mitosis.Ulceration with invasion of the dermis wasusually seen around the abscessed hair fol-licles. At this stage, the hair follicles wereseverely involved with necrosis of the ger-minal layers, purulent exudates around thehair shaft and in the adjacent dermal pa-pillae, and heavy invasion of coccoid bac-teria around the hair shaft. The dermal tis-sues were edematous with congestion ofthe papillary vessels, heavy infiltration ofthe superficial layers by neutrophils, eosi-nophils, lymphocytes and plasma cells. Thedeeper portions of the hair follicles did notseem to be involved, nor were any changesseen beyond the papillary layer of the der-mis. The sebaceous glands were intact andthe sweat glands were active in some casesand dilated in others.

DiscussionThe results of the experimental inocula-

tion of pigs with skin scrapings from fieldand experimentally produced cases of exu-dative epidermitis clearly indicate the in-fectious nature of this disease. Further-more the clear-cut results obtained by theinoculation either by scarification or in-travenously of pure cultures of 4 strains ofMicrococcus sp. indicate that these organ-isms are of primary etiological signifi-cance in the production of exudative epider-mitis. That other bacterial organisms (C.pyogenes, streptococci) may be of second-ary importance in producing the verysevere and fatal forms of this disease islikely. Viral agents would seem to play nopart in the primary etiology of exudativeepidermitis as seen in weaned pigs. Thenegative results on inoculation of sterile,antibiotic treated or filtered scraping sus-pensions would tend to discount the possi-ble significance of virus agents in thisdisease.The clinical evolution of the skin disease

and the lesions produced following experi-mental inoculation of the micrococcus or-ganisms was similar to that seen in thefield or in contact transmission trials. Thecausative micrococcus organism seems topossess extraordinary epidermotropic char-acteristics. Following intravenous inocula-tion of broth cultures the only significantlesions, save a mild serous polyarthritis,were the exudative epidermitis lesionsdescribed. The ability of this organism toproduce lesions in the skin and proliferatein this tissue was in marked contrast to itsinability to survive in the visceral organsand tissues. *The micrococcus organismsinoculated were not recovered from any ofthe joints showing the mild serous arthritisat time of necropsy, some 7 or 8 days PI.However the organism seems to have theability to localize and proliferate in theepidermal layers of the skin as shown bythe identification of microcolonies of coc-coid organisms in histopathological sectionsof infected skin and by reisolation of ap-parently identical strains upon bacteriolo-gical culture of these same lesions. Thefinal species classification of these micro-coccus strains must await further studiesin depth of the physiological characteristicsof these organisms. Tentatively thesestrains all seem to uniformly possess thephysiological characteristics described forthe strain Micrococcus hyicus by Som-

Can. J. Comp. Med. Vet. Sci.100

polinsky (12). Further studies are beingundertaken in an attempt to properlyclassify this organism either among thestaphylococci or the micrococci.

Histopathological studies of the skinlesions produced following inoculation byscarification or intravenously of strains ofmicrococci revealed lesions which were ap-parently identical to those previously de-scribed by Hjjarre (10), Jones (1) andSompolinsky (11). These lesions were es-sentially limited to the superficial epider-mal layers with the deep epidermal layersand dermis becoming involved only in themost severe cases. It must be pointed outthat the lesions described here representthose produced by uncomplicated infectionswith the primary etiological agent. Thelesions seen in field cases may vary consi-derably in relation to those described heredue to the regular presence in the field ofsecondary complicating infections.

ACKNOWLEDGMENTS

The authors wish to express their appre-ciation to Mr. S. Klosevych, BiographicUnit, Scientific Information Section, Re-search Branch, Canada Agriculture for thephotomicrography. Technical Assistancewas provided by Mr. A. Beauvais, J. De-broux, R. Marenger, and G. Shock.

REFEREN CES

1. JONES, L. D. Exudative epidermitis of pigs. Am.J. Vet. Res. 17: 179-193. 1956.

2. JONES, L. D. Observations on exudative epidermitis.Vet. Med. 56: 95-103. 1961.

3. RISTIC, M., SANDERS, D. A. and WALLACE,H. D. Seborrhea oleosa in pigs. Vet. Med. 51: 421-422. 1°56.

4. TERPSTRA, J. I. and AKKERMANS, J. P. W. M.De dermatitis crustosa van het varken. Tydschr.Diergeneesk. 81: 755-762. 1956.

5. SANDBU, E. H. Impetigo contagiosa. En del under-solkelser, over silukdombnens arsakisforhold. NbrdVeterinarnotet VIII: 85-92, 1959.

6. BEHRENS, H. Vitamin-A-Bestimmungen bei Ferkelnmit seborrhoischen Ekzem. Dtsch. tierarzt. Wschr.72: 386-388. 1965.

7. IMAI, M., KAMIMURA, T., and TABUCHI, K.Papular dermatitis in pigs II. Pathogenicity of As-pergillus strains for pigs and precipitin and intra-dermal tests. Bull. Azabu Vet. Coll. 8: 91-104, 1961.Abstr. in Vet. Bull., 32: 741. 1962.

8. HANSON, L. J. Studies on parakeratosis and exuda-tive epidermitis in swine. Dissertation. University ofMinnesota, 1962, 104 pages. University Microfilms,Ann Arbor, Michigan.

9. L'ECUYER, C. Exudative epidermitis in pigs. Clinic-al studies and preliminary transmission trials.Canad. J. Comp. Med. 30: 9-16. 1966.

10. HJARRE, A. Kontagios pyodermi hos svin. Skand.Vet. Tidskrift 38: 662-682. 1948.

11. SOMPOLINSKY, D. Impetigo contagiosa suis. Dansk.Maanedsskrift Dyrlaeger 61: 401-453. 1950.

12. SOMPOLINSKY, D. De l'impetigo contagiosa suis etdu Micrococcus hyicus n. sp. Schweiz. Arch. Tier-keilk. 95: 302-309. 1953.

13. UJNDERDAHL, N. R., GRACE, 0. D. and YOUNG,G. A. Experimental transmission of exudative epider-mitis of pigs. J. Amer. Vet. Med. Ass. 142: 754-762.1963.

14. UNDERDAHL, N. R., GRACE, 0. D. and TWIE-HAUS, M. J. Porcine exudative epidermitis: charac-terization of bacterial agent. Am. J. Vet. Res. 26:617-624. 1965.

Case Report - Kidney Removal in a CowA successful removal of a kidney in a

cow was reported to this Journal by Dr.R. P. Jobin, La Guadeloupe, Frontenac,Quebec. Dr. Jobin described four attemptsat nephrectomy in which three cases werediscarded because of bilateral involvement.Dr. Jobin established his diagnosis on thebasis of symptoms and rectal examination.The site of entry was the left side, usingsedation and a local anesthectic, the cowstanding during the surgery. Dr. Jobin in-cised through the skin, muscles and perito-neum, 24 inches in length. The diseasedkidney was removed after ligating theuterer, vein and artery. Upon removal the

Vol. 30 - April, 1966

infected kidney burst, revealing the con-tents of brown coloured pus. Closure wasaffected in the usual way. Post operativesupportive therapy including fluids, anti-biotics and steroids. Rumen extracts werealso used. The cow improved daily till theeleventh day when a temperature elevationwas noted. 0 nthe 18th day the patientbegan to give milk. Eight weeks aftersurgery the cow gave 10-15 pounds of milkdaily and gained 100 lbs in weight.

Dr. Jobin feels that nephrectomy in thebovins is not any more difficult thancaesarian section.

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