Transmission of Campylobacter spp. in a poultry slaughterhouse and genetic characterisation of the isolates by pulsed-field gel electrophoresis

1. Contamination of retail products with Campylobacter spp. during the slaughter of poultry is a well-known problem of product hygiene. Mechanical evisceration often leads to intestinal rupture and discharge of gut contents, which can contain zoonotic and human pathogens. Processes along the slaughter line cause aerosols and airborne droplets, containing bacterial loads. 2. To estimate the possible transmission routes of intestinal Campylobacter, 36 measurements of the bioaerosol (Andersen sampler and SKC BioSampler), 30 cloacal (of three flocks), 10 equipment and 4 sedimentation samples were tested for the presence of Campylobacter species. 3. The results imply that, in addition to contaminated equipment, which was Campylobacter-positive in 80% of cases, aerosols with peak values of 4.0 x 10(4) (test series 1) and 1.4 x 10(4) (test series 2) CFU/m3 also provide a potential vector for horizontal transmission. 4. To explore the genetic similarities of isolates from different origins, 18 isolates recovered from air, 26 cloacal, 8 equipment and 4 sedimentation isolates were analysed by pulsed-field gel electrophoresis (PFGE), using the restriction enzymes Sma I and Sal I. The similarity of cloacal isolates with isolates from equipment, air and sediment, suggest that the contamination is of intestinal origin. 5. There were direct links between Campylobacter-positive flocks and the presence of the same strains in the aerosol of the slaughter hall. Air as a potential source for microbial transmission must be taken into account.     

Distribution of Campylobacter jejuni isolates from turkey farms and different stages at slaughter using pulsed-field gel electrophoresis and flaA-short variable region sequencing

The aim of this study was to assess the diversity of thermotolerant Campylobacter spp. isolated from turkey flocks at six rearing farms 1-2 weeks prior to slaughter (360 faecal swab samples) and from 11 different stages at the slaughterhouse (636 caecal, environmental, neck skin and meat samples). A total of 121 Campylobacter isolates were identified to species level using a multiplex PCR assay and were typed by pulsed-field gel electrophoresis (PFGE) and flaA-short variable region (SVR) sequencing. All Campylobacter isolates were identified as Campylobacter jejuni. PFGE analysis with KpnI restriction enzyme resulted in 11 PFGE types (I-XI) and flaA SVR typing yielded in nine flaA-SVR alleles. The Campylobacter-positive turkey flocks A, C and E were colonized by a limited number of Campylobacter clones at the farm and slaughter. The present study confirms the traceability of flock-specific strains (PFGE types I, V and IX; flaA types 21, 36 and 161) from the farm along the entire processing line to meat cuts. It seems that stress factors such as high temperature of the defeathering water (54-56 °C), drying of the carcass skin during air chilling (24 h at 2 °C), and oxygen in the air could not eliminate Campylobacter completely. Campylobacter-negative flocks became contaminated during processing by the same subtypes of Campylobacter introduced into the slaughter house by preceeding positive flocks even if they were slaughtered on subsequent days. Proper and efficient cleaning and disinfection of slaughter and processing premises are needed to avoid cross-contamination, especially in countries with a low prevalence of Campylobacter spp. The majority of flaA SVR alleles displayed a distinct association with a specific PFGE type. However, a linear relationship for all strains among both typing methods could not be established. To specify genetic relatedness of strains, a combination of different genotyping methods, is needed.     

Enteric colonisation following natural exposure to Campylobacter in pigs

A survey was conducted to establish the prevalence of Campylobacter in pigs from an integrated commercial hog farm. This study was carried out in four different groups of pigs: 1) adult gilts (50); 2) pregnant sows (9); 3) piglets at day-of-birth (73); 4) weaned piglets (20). Rectal and/or caecal samples were collected from each pig. Campylobacter was cultured and enumerated from such samples using Bolton enrichment broth and Campy-Cephex agar plates. Both biochemical and serological tests were used to determine Campylobacter species. Gilts had a 76 per cent incidence of Campylobacter with a mean of 76.3 per cent for C. jejuni, 21 per cent for C. coli and 2.6 per cent for C. lari. Pregnant sows had a 100 per cent incidence of Campylobacter with a mean of 87 per cent for C. jejuni and 13 per cent for C. coli. Newborn piglets had a 57. 8 per cent incidence of Campylobacter, rising to 100 per cent by the time of weaning. Thus it appears that pigs, from the day of birth, are highly susceptible to colonisation by Campylobacter.     

Recovery of Campylobacter jejuni in feces and semen of caged broiler breeder roosters following three routes of inoculation

We previously reported the recovery of Campylobacter (naturally colonized) from the ductus deferens of 5 of 101 broiler breeder roosters, and four of those five positive roosters had previously produced Campylobacter-positive semen samples. Those results prompted further evaluation to determine if inoculation route influenced the prevalence or level of Campylobacter contamination of semen, the digestive tract, or reproductive organs. Individually caged roosters, confirmed to be feces and semen negative for Campylobacter, were challenged with a marker strain of Campylobacter jejuni either orally using 1.0 ml of a diluted cell suspension (log(10)4.3 to 6.0 cells), by dropping 0.1 ml of suspension (log(10)5.3 to 7.0 cells) on the everted phallus immediately after semen collection or by dip coating an ultrasound probe in the diluted cell suspension (log(10)4.3 to 6.0 cells) and then inserting the probe through the vent into the colon. Six days postinoculation, individual feces and semen samples were again collected and cultured for Campylobacter. Seven days postinoculation, roosters were killed, the abdomen aseptically opened to expose the viscera, and one cecum, one testis, and both ductus deferens were collected. The samples were then suspended 1:3 (weight/volume) in Bolton enrichment broth for the culture of Campylobacter. Samples were also directly plated onto Cefex agar to enumerate Campylobacter. Campylobacter was recovered 6 days after challenge from feces in 82% of samples (log(10)4.1 colony-forming units [CFU]/g sample), 85% of semen samples (log(10)2.9 CFU/ml), and on the seventh day postchallenge from 88% of cecal samples (log(10)5.8 CFU/g sample). Campylobacter was not directly isolated from any testis sample but was detected following enrichment from 9% (3/33) of ductus deferens samples. Roosters challenged with Campylobacter orally, on the phallus, or by insertion of a Campylobacter dip-coated ultrasound probe were all readily colonized in the ceca and produced Campylobacter-positive semen and feces on day 6 after challenge. The low prevalence of recovery of Campylobacter from the ductus deferens samples and failure to recover from any testis sample suggests that semen may become Campylobacter positive while traversing the cloaca upon the everted phallus. The production of Campylobacter-positive semen could provide a route in addition to fecal-oral for the horizontal transmission of Campylobacter from the rooster to the reproductive tract of the hen.     

Prevalence of thermophilic Campylobacter species in cats and dogs in two animal shelters in Ireland

Rectal swabs or faecal samples for the isolation of Campylobacter species were taken from 120 dogs and cats in an animal shelter in which only one kitten showed signs of gastrointestinal disease, and rectal swabs were taken from 46 dogs, 22 of which showed signs of gastrointestinal disease, in another shelter. At the first shelter, the swabs from 24 of 47 dogs (51.1 per cent) and 36 of 48 cats (75 per cent) yielded a Campylobacter species. The rate of isolation was significantly higher from dogs and cats less than six months old, and significantly higher from cats than from dogs (P< or =0.05). At the second shelter Campylobacter species were isolated from 40 of 46 dogs (87 per cent), but there was no significant difference between the age groups. Campylobacter species were isolated from 19 (86.4 per cent) of the 22 dogs with signs of gastrointestinal disease and from 21 (87.5 per cent) of the 24 unaffected dogs. Several culture methods were applied to the samples collected from both shelters, and the combination significantly increased the recovery of Campylobacter species.     

Survey of campylobacter, salmonella and mycoplasmas in house crows (Corvus splendens) in Malaysia

House crows (Corvus splendens) in Selangor, Malaysia were examined for the presence of Campylobacter species, Salmonella species, Mycoplasma gallisepticum and Mycoplasma synoviae by serology, culture and pcr. For the detection of Campylobacter and Salmonella species swabs were taken either from the intestine or cloaca. For the detection of mycoplasmas, swabs were taken either from the choanal cleft or trachea for culture and pcr and serum samples were tested by the rapid serum agglutination (rsa) and monoclonal antibody-blocking elisa (mbelisa) for antibodies to M gallisepticum and M synoviae. For campylobacter, 25.3 per cent of the crows were positive by culture, and the species identified were Campylobacter jejuni and Campylobacter coli. No Salmonella species were isolated. Four of 24 swabs were positive for M gallisepticum dna but none gave positive results for M synoviae dna. No M gallisepticum or M synoviae antibodies were detected by rsa but 60 per cent of the sera gave positive reactions for M gallisepticum and 13 per cent gave positive reactions for M synoviae by mbelisa.     

Campylobacter in the dog: a clinical and experimental study

Faecal samples from 54 dogs with diarrhoea and 54 control dogs were cultured for Campylobacter, Salmonella and Yersinia species and controlled for enteric viruses. The campylobacter were identified as either C jejuni/coli or C upsaliensis. In the diarrhoeic group 16 dogs (29.6 per cent) were positive for campylobacter, 10 C upsaliensis and six C jejuni/coli. Concomitant infection with parvovirus was evident in six of the dogs with diarrhoea and campylobacter-positive faecal cultures. In the control group 13 dogs (24.1 per cent) were positive for campylobacter; three of the isolates were C upsaliensis and six C jejuni/coli. Four isolates could not be identified. The most prominent clinical findings in naturally occurring cases were an acute onset of vomiting (12 of 16), diarrhoea (16 of 16) which was often haemorrhagic (nine of 16) and a raised rectal temperature. Dogs were infected experimentally with both C jejuni (three dogs) and C upsaliensis (three dogs). The challenge strains could be identified in faecal samples from all the dogs, but clinical signs of diarrhoea were seen in only one dog infected with C jejuni. Soft faeces was passed by one dog infected with C upsaliensis. It is concluded that C jejuni/coli or C upsaliensis are either primary pathogens or, after predisposing factors such as virus infections, act as secondary pathogens. It also seems probable that Campylobacter species are present in the intestinal flora of the normal dog.     

Prevalence of Campylobacter and four endoparasites in dog populations associated with Hearing Dogs

OBJECTIVES: This study established the prevalence of four gastrointestinal parasites (Isopora species, Giardia species, Uncinaria stenocephala, Toxocara canis) and one bacterial infection (Campylobacter jejuni/coli) in dogs associated with the charity Hearing Dogs for Deaf People. METHODS: Dogs' faeces were routinely sampled from dogs according to whether they were in Socialising, Kennelling or Visiting the Hearing Dogs site. A further group consisted of dogs with diarrhoea. RESULTS: Prevalence rates for dogs in Socialising (n=326), Kennelling (n=117), Visiting (n=106) and Diarrhoea (n=59) groups, respectively, were as follows: Campylobacter- 26, 21, 15 and 31 per cent; Coccidia - 3, 0, 0 and 2 per cent; Giardia- 13, 3, 2 and 10 per cent; hookworm - 1, 1, 4 and 5 per cent; and Toxocara- 4, 2, 3 and 2 per cent. There were significant differences in the levels of Giardia and hookworm found between the four different groups of dogs. No significant gender differences were found, and dogs that were positive for Campylobacter in the Visiting group were significantly younger. CLINICAL SIGNIFICANCE: This study provides current information on the infection rates in specific dog populations in the UK. This is relevant to the veterinary health of dogs and the possible risk of zoonotic infection to humans.     

Comparative studies on detection of Chlamydophila psittaci and Chlamydophila abortus in meat turkey flocks using cell culture, ELISA, and PCR

The prevalence of chlamydia in 10 meat turkey flocks was investigated. As samples served of each moment of collection and sex of the animals 10 cloacal swabs which were taken at the age of 1, 4, 8 and 12 (females) or 16 weeks (males) and at the time of slaughter at the age of 16 or 20 weeks. Spleen samples were taken at the time of slaughter, additionally. These were pooled making 1 pool out of 5 individual samples. The cloacal and spleen pools were examined by nested PCR (nPCR), Capture-ELISA and Capture Blocking-ELISA directly as well as after isolation attempts in cell cultures. The most sensitive method to detect chlamydia, with 6 isolates proved to be the isolation by cell culture followed by detection using nPCR. Not corresponding to the results of the nPCR were 4 positive reactions found by the Capture-ELISA which could in no case be affirmed by Capture-Blocking-ELISA. The direct examination of cloacal swab pools by nPCR proved positive in only 2 cases. In contrast to this the examination of these samples by Capture-ELISA showed a high percentage of 71.9% positive results, of which only 2 cases were confirmed by nPCR and none by Capture-Blocking-ELISA. Of the 8 Chlamydia positive results in the nPCR 7 could be classified by DNA sequencing to Cp. abortus and only one to Cp. psittaci.     

Immunopathological investigations on bovine digital epidermitis

Paraffin-embedded fragments of bovine digital skin lesions were sectioned and stained with Warthin-Starry, haematoxylin and eosin, Grocott's methenamine silver and immunohistochemical techniques. Microorganisms observed in the silver-stained sections were classified into four major morphological groups. Spirochaetes were the most prevalent organisms, but bacillary and coccoid elements were also present in most sections. Immunohistochemical probing demonstrated that approximately 80 per cent, 46 per cent and 41 per cent of the digital and interdigital dermatitis sections stained positively with polyclonal antisera to Treponema pallidum, Campylobacter jejuni and Fusobacterium necrophorum, respectively. An unidentified branching filamentous organism (presumed to be an actinomycete) was consistently present in the sections of samples from mild interdigital lesions.     

Detection of pigeon circovirus in cloacal swabs: implications for diagnosis, epidemiology and control

Pigeon circovirus (picv) was detected in cloacal swab samples by means of a newly-developed, sensitive pcr. An initial investigation of 17 Belgian racing pigeons aged up to eight months showed that rates of detection of 88 per cent and above were achieved using samples of cloacal swab, blood and bursa of Fabricius. The sampling of 15 caged pigeons six times when they were from three to 31 weeks of age indicated that picv infections were more readily detected in cloacal swabs than in blood, and that the virus could be detected in cloacal swabs for longer periods after infection than in blood. picv infections were detected in cloacal swabs from 38 of 47 young pigeons aged from two to 31 weeks, from 12 racing lofts, which had clinical signs including diarrhoea and weight loss, regurgitation and respiratory signs. Samples from birds from two infected lofts indicated that picv could be detected in some birds for at least 27 weeks. Although nine of 14 pigeons aged from 32 to 45 weeks were virus-positive, picv was detected in only one of 18 adult pigeons that originated from four infected lofts.     

Risk factors for Campylobacter colonization in broiler flocks in Japan

The present study was conducted to estimate the prevalence of and to identify the risk factors for Campylobacter colonization in broiler flocks in Japan. Campylobacter colonization status in flock was evaluated by culturing pooled caecal excrement from 124 broiler flocks. Potential exposure to risk factors was evaluated with a questionnaire for the broiler producers. Odds ratios (ORs) were calculated using a multivariable logistic regression analysis. The prevalence of Campylobacter-positive flocks was 43.5% (upper and lower limits of 95% confidence interval (CI(95%) ): 34.8, 52.3). Multivariable logistic regression model identified two variables as risk factors for Campylobacter colonization. The ORs of Campylobacter colonization were higher in flocks in western Japan (OR=2.68; CI(95%) : 1.04, 6.91) than in eastern Japan, and in flocks supplied with undisinfected drinking water (OR=7.41; CI(95%) : 3.11, 17.66) than in those supplied with disinfected drinking water. These findings indicate that water may play an important role in Campylobacter colonization in broiler flocks in Japan and the use of disinfected water may reduce the risk of Campylobacter colonization.     

Dynamics of Campylobacter spp. spread investigated in 14 broiler flocks in Switzerland

Ten conventional and four extensive outdoor broiler flocks, distributed over nine farms, were investigated twice per week during a 35-58-day rearing period to observe the dynamics of Campylobacter spp. spread within these flocks. Strains isolated during this period were genotyped by restriction fragment length polymorphism analysis of the flaA gene and macrorestriction profiling with pulsed field gel electrophoresis. A total of 4112 samples were collected; 157 (3.8%) of these samples were Campylobacter positive, with all C. jejuni. The positive samples were distributed over three conventional and two extensive outdoor flocks on five farms. These five positive flocks were colonized from the fifth to the seventh week of age and remained colonized until slaughter. Each of the flocks showed a flock-specific genotype of Campylobacter that predominated until slaughter. Presuming different ways of entry, a combination of this fact and the observed dynamics of C. jejuni spread within the flocks indicates that a single source from the environment may have been responsible for the colonization of each flock. These conclusions may serve to further develop combat strategies at farm level.     

Bayesian estimation of true between-herd and within-herd prevalence of Salmonella in Danish veal calves

Specialised veal producers that purchase and raise calves from several dairy herds are potentially at high risk of delivering Salmonella-infected animals to slaughter. However, the true prevalence of Salmonella infected veal producing herds and the prevalence of infected calves delivered to slaughter from infected herds are unknown in Denmark. Due to uncertainties about test sensitivity and specificity, these prevalences are not straightforward to assess. The objective of this study was to estimate the within-herd- and between-herd prevalence of Salmonella in veal calves delivered for slaughter to abattoirs in Denmark. Furthermore, it was investigated to which extent the estimates differed between a setup using both serological tests and faecal culture, compared to just serological tests, and whether the applied sampling scheme in the national surveillance programme in Denmark was sufficient to establish high posterior estimates of freedom from infection in individual herds. We used Bayesian analysis to avoid bias as a result of fixed test validity estimates. Serological test results from 753 animals and faecal culture from 1233 animals from 68 randomly selected Danish veal producing herds that delivered more than 100 calves to slaughter per year were used to estimate the prevalences and estimates of freedom from Salmonella. Serological test results of 7726 animals from 185 herds were used to compare the difference in prevalence estimates between serology alone vs. faecal culture combined with serology. We estimated that 34-57% of specialised veal producing herds were infected with Salmonella. Within the infected herds, 21-49% of the animals were infected. Few herds obtained high posterior estimates for the probability of freedom from infection given the collected data, with only six of 68 herds obtaining posterior probability of being infected less than 10%. Furthermore, this study indicated that serology is sufficiently sensitive and specific to be used for estimating the prevalence of Salmonella-infected specialised veal producing herds.     

Salmonella serotypes present on a sample of Irish pig farms

A survey of the prevalence of Salmonella species infection was conducted on 59 Irish farrow-to-finish pig herds. Faecal samples were collected from the pens of first-stage weaners (growing pigs approximately three to 10 weeks of age), second-stage weaners (approximately 10 to 17 weeks of age) and fatteners, and from the dry sow and farrowing sow houses. The prevalence of infection was estimated to within 5 per cent with a 95 per cent confidence interval. Thirty of the 59 herds were infected, 12 with Salmonella Typhimurium only, eight with Salmonella Derby only and seven with both S Typhimurium and S Derby; serotypes London, Livingstone and Infantis were each isolated from a single herd. Farms in Ireland are assigned to one of three infection categories on the basis of the antibody levels in samples of meat juice taken at slaughter. When a herd was classified as either positive or negative on the basis of the isolation of Salmonella from at least one faecal sample there was no association between the herd's category as determined by meat juice serology and the probability of the isolation of Salmonella from the faecal samples. However, there were differences in prevalence between pigs at different stages of production in herds of different categories. Farrowing sow houses in moderately infected (category 2) herds had significantly lower infection rates (P < or = 0.05) than other herd categories and other stages of production. Pigs from first-stage weaner pens in slightly infected (category 1) herds were more likely to be infected with Salmonella than pigs at any other stage of production or category of herd.     

Isolation of Campylobacter spp. from semen samples of commercial broiler breeder roosters

Pooled semen samples from 12 groups of mature commercial broiler breeder roosters were analyzed for the presence of Campylobacter. Each of the 12 groups was comprised of eight individuals and was sampled weekly for five consecutive weeks. Once a day, roosters were allowed to have a restricted amount of feed after the semen samples were collected by abdominal massage. This feeding schedule reduced the amount of fecal contamination in and around the vent as well as in the semen sample. For replications 1, 2, and 3, the numbers of Campylobacter-positive groups were 8, 5, and 5, respectively, out of 12. For replications 4 and 5, 6 of 8 and 6 of 11 groups were positive, respectively. Only two groups were positive for Campylobacter at all sampling times, two groups were negative each time, and eight groups produced variable results. Also, fecal droppings, external swabs of the genitalia, and semen samples were taken from individual roosters between 49 to 65 wk of age. Of the total 275 semen samples collected, 9.47% contained naturally occurring Campylobacter, whereas 9.6% of 114 fecal droppings and 7.9% of the 114 genital swabs were positive. Levels of the organism present in the fecal samples ranged from 1.0 to 4.2 log colony-forming units (CFU)/g with an average of 2.9 log CFU/g feces. For semen, the levels ranged from as low as enrichment recovery only to as high as 3.1 log CFU/ml of semen with an average of 1.2 log CFU/ml. For swabs of genitalia, the levels of Campylobacter were so low that recovery was achieved only through enrichment. These data suggest that rooster semen may serve as a vehicle for transmission of Campylobacter to the reproductive tract of the hen and subsequently to the fertile egg.     

Prevalence of Campylobacter jejuni and Salmonella during pig slaughtering

It was found that 79% of healthy pigs, slaughtered in three different slaughterhouses in the Netherlands, were intestinal carriers of Campylobacter jejuni (mean number 4000 cfu per g), and 21% of the same pigs had Salmonella in the intestinal tract (mean number 10 cfu per g). Immediately after slaughter, Campylobacter was swabbed from 9% of the carcasses and Salmonella from 13%. It is concluded from these data that most of the contamination on carcasses does not originate directly from the intestinal tracts of the animals but rather from surfaces, equipment, and utensils in the slaughter hall. It was demonstrated that Salmonella could survive in the slaughter hall, whereas Campylobacter died off, probably due to its vulnerability to drying conditions and its inability to grow at temperatures below 30 degrees C. Campylobacter was not isolated from the carcasses after cooling. It had been shown earlier that this again was caused by dry conditions, brought about by the use of forced ventilation in the cooling rooms. In an additional investigation, Campylobacter was not isolated from 248 samples of minced pork (10 g each), whereas Salmonella was found in 13% of these samples.     

Vaccination studies for the control of campylobacteriosis in Jamaican cattle

Following the first diagnosis of campylobacteriosis in Jamaican cattle a field study was undertaken to determine the pathogenicity of Campylobacter fetus subspecies venerealis Jam (Jamaican strain) and to evaluate the effectiveness of vaccination in controlling the disease. A total of 46 nonpregnant yearling heifers and four two-year-old bulls were used in two separate experiments. The results showed that C fetus subspecies venerealis Jam readily colonised the reproductive tract of susceptible heifers and persisted in some animals (68 per cent of unvaccinated and 33 per cent of vaccinated animals) for the duration of the experiment. Pregnancy was confirmed in 13 of 18 (72 per cent) culture-negative heifers but in only eight of 28 (29 per cent) of the heifers with two or more positive cultures. Vaccination appeared to be curative because 44 per cent of vaccinated heifers were cleared of infection whereas 85 per cent of unvaccinated, inoculated heifers remained infected for at least 17 weeks. Vaccination improved the fertility level of the infected heifers threefold. Infection was not established in vaccinated bulls used for breeding infected heifers.     

Use of an avirulent live Salmonella Choleraesuis vaccine to reduce the prevalence of Salmonella carrier pigs at slaughter

This study evaluated the use of an avirulent live Salmonella Choleraesuis vaccine to reduce the seroprevalence and number of Salmonella carrier pigs at slaughter. Seven batches of 500 pigs were included in each of the two study groups: the vaccinated group (VG) that was orally vaccinated and the control group (CG) that received a placebo on the first day of life. The groups were managed in a three-site system and followed up from birth to slaughter. Blood samples (n=378) were collected from each VG and CG to monitor the on-farm seroprevalence in both groups. Mesenteric lymph nodes and blood from animals (n=390) belonging to each group were collected at slaughter. At the first day of life, the seroprevalence in control batches ranged from 77.9 to 96.3 per cent, while in vaccinated batches, it ranged from 66.6 to 92.6 per cent. At weaning (21 days of age), the number of seropositives decreased in both groups (mean of 12 and 3.7 per cent for CG and VG, respectively). At slaughter, batches of VG had a significantly (P<0.0001) lower seroprevalence (46.6±5 per cent) and isolation of Salmonella from lymph nodes (33.1±5 per cent) compared with CG batches (79.7±4 per cent and 59.5±5 per cent, respectively). The results indicate that administration of a Salmonella choleraesuis-attenuated vaccine on the first day of life decreases Salmonella isolation and seroprevalence in pigs at slaughter.     

Sarcoptic mite hypersensitivity: a cause of dermatitis in fattening pigs at slaughter

The prevalence of Sarcoptes scabiei in pigs in the Netherlands, and the causal relationship between infestation and dermatitis in fattening pigs were assessed in a survey in 1988. In the first part of the survey 400 fattening pigs from 88 farms and 200 sows were examined. In the second part of the survey 193 fattening pigs with normal skin and 201 with dermatitis were examined; the dermatitis was characterised by small round, slightly thickened skin lesions, mostly on the rump, flanks, abdomen and buttocks. Ear scrapings were collected from all the animals after slaughter and examined for the presence of sarcoptic mites. In the first part of the survey, 33 (8.25 per cent) of the 400 fattening pigs and nine (4.5 per cent) of the 200 sows were positive for S scabiei. Mange was detected in fattening pigs from 21 (23.9 per cent) of the 88 farms. In the second part of the survey, six (3.1 per cent) of the 193 fattening pigs with normal skin and 30 (14.9 per cent) of the 201 pigs with dermatitis were positive for S scabiei. This difference was statistically significant (P less than 0.001). Histological examination of the skin lesions revealed an eosinophilic perivasculitis compatible with an allergic reaction, and consistent with infestation with S scabiei. The results of this survey indicate that mange is common in the Netherlands, and that sarcoptic mite hypersensitivity can be a cause of the skin lesions seen in fattening pigs at slaughter.