CAMPYLOBACTER JEJUNI IN . SLAUGHTERED CmCKENS FROM THE VIEWPOINT OF FOOD HYGmNE

MatdovsU Norika, Olga SladU, o. Mdz, Z. MatyU and Iva Tomancova: Campylobacter jejuni in Slaughtered Chickens from the Viewpoint of Food Hygiene. Acta vet. Bmo, 61, 1992: 61-67. A total of 440 slaughtered chickens coming from 27 farms were examined for presence of Campylobacter jejuni between 1st Feb. 1990 and 31st Tan. 1991. The relevant specimens were taken from the outer and inner carcass surfaces, ileum contents, liver parenchyma and bile from groups of 10 birds each week. Isolation attempts yielded 366 C. jejuni strains. Of the 38 and 47 (10.3 % and 12.8 %) were isolated from the outer and inner carcass surfaces, respectively, 121 (35 %) from ileum contents, 92 (25 %) from liver parenchyma and 68 (18.6 %) from bile. The proportions of contaminated chicken carcasses showed two peaks, reaching 62.5 % and 62 % in Mayand October, respectively. An almost parallel trend vas recorded for the isolations from ileum contents and liver parenchyma where the highest number of strains (45 % and 30 % respectively) coincided with the May peak, whereas the highest proportions of isolations from bile (30 %) coincided rather with the second peak. The proportions of C. jejuni isolated from the outer and inner carcass surfaces were relatively low, averaging 9.4 % and 11.4 % respectively, and did not show much fluctuation. The proportions of C. jejuni isolated from bile averaged 13.8 %. In 82 (22.4 %) C. jejuni strains solitary colonies were observed also after control aerobic incubation at 42 °c, but attempts at their further passage under these conditions yielded negative results. C. jejuni carriers and shedders as well as the incidence of asymptomatic C. jejuni infection among chickens do not urge either the farmer or the veterinarian to take any measures, but the consumption of C.jejuniinfected chicken meat constitutes a major health hazard for man. Campylobacter jejuni, slaughtered chickens, food hygiene Campylobacter jejuni was first described as Vibrio jejuni a ones et a1. 1931) and is also known under the names of Vibrio hepaticus (Mathey and Rissberger 1964) or Campylobacter fetus subsp. jejuni (Smibert 1974). It is a causative agent of abortion in sheep, diarrhoea in calves and lambs, campylobacter hepatitis in chickens and febrile enteritis in man. A point of particular epidemiological importance is the fact that C. jejuni can also be iso'ated from the intestinal tract of clinically healthy cattle, sheep, goats, pigs, rabbits, domestic fowls, nirkeys, ducks, pigeons, dogs, cats, monkeys, sparrows, blackbirds and starlings (Smibert 1984). From the intestinal tract it can make its way to the liver and, upon evisceration, also to the outer and inner surfaces of farm animal carcasses. In the domestic fowl this possibility has been demonstrated: (1) on the outer sUrface after scalding and plucking (Baker et al. 1987) in 20 % of the carcasses; (2) on the inner surface after evisceration (Pl!gfimkova 1986, Marinescu et al. 1987; Mfl!kova 1987) in 28.7 % to 92 % of the carcasses; (3) in the liver (Khalafalla 1990) in 40 % of the carcasses. Examination of the bile has yielded negative results (00 sterom et al. 1983).

The proportions of contaminated chicken carcasses showed two peaks, reaching 62.5 % and 62 % in Mayand October, respectively.An almost parallel trend vas recorded for the isolations from ileum contents and liver parenchyma where the highest number of strains (45 % and 30 % respectively) coincided with the May peak, whereas the highest proportions of isolations from bile (30 %) coincided rather with the second peak.The proportions of C. jejuni isolated from the outer and inner carcass surfaces were relatively low, averaging 9.4 % and 11.4 % respectively, and did not show much fluctuation.The proportions of C. jejuni isolated from bile averaged 13.8 %.
In 82 (22.4 %) C. jejuni strains solitary colonies were observed also after control aerobic incubation at 42 °c, but attempts at their further passage under these conditions yielded negative results.C. jejuni carriers and shedders as well as the incidence of asymptomatic C. jejuni infection among chickens do not urge either the farmer or the veterinarian to take any measures, but the consumption of C.jejuni-infected chicken meat constitutes a major health hazard for man.

Campylobacter jejuni, slaughtered chickens, food hygiene
Campylobacter jejuni was first described as Vibrio jejuni a ones et a1.1931) and is also known under the names of Vibrio hepaticus (Mathey and Rissberger 1964) or Campylobacter fetus subsp.jejuni (Smibert 1974).It is a causative agent of abortion in sheep, diarrhoea in calves and lambs, campylobacter hepatitis in chickens and febrile enteritis in man.
A point of particular epidemiological importance is the fact that C. jejuni can also be iso'ated from the intestinal tract of clinically healthy cattle, sheep, goats, pigs, rabbits, domestic fowls, nirkeys, ducks, pigeons, dogs, cats, monkeys, sparrows, blackbirds and starlings (Smibert 1984).From the intestinal tract it can make its way to the liver and, upon evisceration, also to the outer and inner surfaces of farm animal carcasses.In the domestic fowl this possibility has been demonstrated: (1) on the outer sUrface after scalding and plucking (Baker et al. 1987) in 20 % of the carcasses; (2) on the inner surface after evisceration (Pl!gfimkova 1986, Marinescu et al. 1987;Mfl!kova 1987) in 28.7 % to 92 % of the carcasses; (3) in the liver (Khalafalla 1990) in 40 % of the carcasses.
Examination of the bile has yielded negative results (00 sterom et al. 1983).
Further fate of these bacteria depend on the mode of carcass processing and on culinary pro-• cessing of chicken meat.
Campylobacteriosis of this aetiology in man was demonstrated in Europe (Belgium, England, Holland, Sweden), Mrica (Zaire, South Mrica) and Australia in the seventies.In our country it has been described by Tesarova and Kubecova (1982), Kahlich et al. (1983) and Kovacova (1986), but in all these cases direct isolation of C. jejuni from the incriminated food is lacking.According to Oosterom (1985) the main cause of the disease is the consumption of chicken meat or chicken meat products.
Clinical signs of the disease are observed after a 3-to 5-day incubation period.They include pyrexia, headache, back-pain and muscle ache, soon followed by pain in the abdominal region and diarrhoea.The stools are thin to liquid and occasionally bile or blood-tinged.The diarrhoea generally subsides after 2 to 3 days and the.disease as a whole lasts 1 to 2 weeks.Non-medicated patients shed the bacteria for as many as 5 weeks (Butzler and Skirrow 1979).
The present study was designed to obtain information on C. jejuni occurrence in flocks of domestic fowls and on C.jejuni contamination of chicken meat and giblets in our country.

Materials and Methods
A total of 440 chickens coming from 27 farms were examined for the presence of C. jejuni between 1st Feb. 1990 and31 Jan. 1991.The tissue specimens were taken from the (1) outer surface of plucked chicken carcasses, (2) inner surface of eviscerated carcasses, (3) ileum contents, (4) liver parenchyma and ( 5) bile in a poultry slaughter-house from groups of 10 birds each week.Five farms were represented on 2 occasions, two farms on 3 occasions and one farm on 9 occasions.The origin of each group of 10 birds was recorded.
Swabs taken from wet outer and inner carcass surfaces, ileum contents and liver parenchyma as well as 2 to 3 drops of bile obtained with a syringe were each placed into test tubes containing circa 7 ml transport medium (thioglycolate medium IMUNA) completed with 1 % liquid supplement "C" enriched with antibiotics (cephalotin, vankomycin) and trimethoprim.After 24-h incubation at 42°C inoculations were made into blood agar prepared from IMUNA base No.4, 7 % defibrinated horse blood and 1 % supplement "C".Incutation was carried out under micro-• aerophilic conditions at 42°C for 48 h in a modified apparatus according to Hussels as cited by • Hallman (1955).
From suspect colonies (generally showing a tendency to creeping growth) pure cultures were started on the blood agar as described above except that supplement "C" was replaced with its 1 % non-antibiotic version "A".The two supplements were obtained from the Department of Medical Microbiology, Medical Faculty Hospital, Motol, Prague 5.
The nutrient base used for testing for nitrate reduction, indole production, hydrogen sulphide production, glucose oxidation and growth in 1 % glycine contained 2.5 g tryptose peptone, 0.75 g beef extract, 1.25 g NaCl, 0.25 g Na HPO, and 250 ml distilled water.Mter addition of the test substrates, dispensing, steriziliation and inoculation we carried out incubation under microaerophilic conditions at 42 °C.The isolated strains were identified according to the latest edition of Bergey's Manual (Krieg and Holt 1984) and in the light ofthe published data on newly accepted campylobacters (Benjamin et al. 1983;Gebhart et al. 1985;McClung et al. 1983;Neil et al. 1985;Roop et al. 1985;Steele and Owen 1988;Tanner et al. 1981 andTotten et al. 1985).See Table 1.

Results
A total of 366 strains of C. jejuni were isolated from 440 chicken carcasses during 12 months.Of these 38 and 47. were isolated from the outer and inner carcass surfaces~ respectively~ 121 from the ileum contents~ 92 from the liver parenchyma and 68 from bile.
The positive results varied from week to week and from farm to farm~ ranging from 0 to 100 % (with an average of 50 %) without any clear trend.Nevertheless~ --  .In 82 (22.4 %) C. jejuni strains solitary colonies were observed also after control aerobic incubation at 42°C, but attempts at their further passage under these conditions yielded negative results.They were recorded occasionally throughout the year: 9 times (11 %) from the outer surface, 10 times (12.2 %) from the inner surface, 30 times (36.5 %) from the ileum contents, 16 times (19.5 %) from the liver parenchyma and 17 times (20.7 %) from bile.

Discussion
The information on C. jejuni published to date is extensive and a certain gap in the relevant literature regarding the investigations carried out in chickens became apparent.Essentially the same can be said about the characteristics used for the differentiation of campylobacters (see Table1) where vacancies appear mainly in the column "Growth at 30.5 °C".
The cultivation on the nutrient media used in our study and the evaluation of the results presented no difficulties thanks, among other things, to parallel inoculations of C. jejuni CCM 6207 type strain.The findings of solitary colonies growing also under aerobic conditions were due to the fact that we included this control incubation of the isolated strains.Their frequency with respect to the individual organs was more or less equal, amounting to 22.4 ± 5 %.It is of interest to note that similar observations were made in the strains of Campylohacter cryaernphila the subcultures of which were reported to grow under both aerobic and anaerobic conditions (Neil et al. 1985).
The seasonality in the occurrence of C. jejuni strains in our study became apparent particularly in the total percentages of contaminated chicken carcasses peaking in May and October.A similar observation was reported by Doyle (1984) in his study based on the investigation of faeces from laying hens.
The mean proportions of contaminated chickens in our study were twice to 2.5 times lower than those reported by Baker et al. (1987) and Mickova (1987) and the mean proportion of positive findings in the liver parenchyma was half that recorded by Khalafalla (1990).The reasons of these differences are difficult to discuss because they reflect both the epizootiological situation in the flocks and some poultry slaughter-house practices such as temperature of scalding water and general sanitation standard.
For assessing the bactericidal effect of heat treatment of poultry meat products

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• it would have been' of interest to examine the sensitivity of C. jejuni to temperatu-: res used in this operation but these questions have been thoroughly considered by other investigators (Doyle an" Ro.,rnlln 1981;Blankenship and Graven 1982;Matyas and Tomancova 1985).