Bulk growth procedures and a button agglutination test for Campylobacter

Bulk-cell yields were obtained from 4 Campylobacter spp incubated aerobically without the use of a special atmosphere. A button agglutination test was developed for quantitation of blood serum antibodies against C fetus subsp venerealis, C fetus subsp fetus, C jejuni, and "C hyointestinalis." The test was sensitive, and different individuals reading it usually attained the same titers. Cells of C fetus subsp venerealis, C fetus subsp fetus, and "C hyointestinalis" grown aerobically in broth made satisfactory antigens for the button test, but some cell pools of C jejuni had a tendency to autoagglutinate. Cells of C jejuni grown on blood agar had less tendency to autoagglutinate.     

Development and evaluation of an enzyme-linked immunosorbent assay for quantification of the humoral response of cattle vaccinated against Campylobacter fetus

OBJECTIVE: To develop a reliable ELISA by use of a unique antigen preparation for serum IgG quantification after vaccination against Campylobacter fetus in cattle. ANIMALS: Twenty-six 24-month-old virgin Hereford heifers and a naturally infected Hereford bull. PROCEDURES: 5 antigens were prepared from a cell suspension of C fetus. Antigen preparations were the same as those reported in the literature, with the exception of antigens that were obtained by detergent solubilization of a C fetus cell suspension. For each antigen preparation, the optimal ELISA conditions for its immobilization were determined. Biotinylated antibodies against bovine immunoglobulins were obtained and used in the ELISA. Two groups of heifers were inoculated with commercial vaccines according to manufacturers' instructions. A control group was included. The immune response of vaccinated heifers and controls was followed for 6 months. RESULTS: Detergent solubilized C fetus antigens resulted in better ELISA performance than other antigen preparations. Antigens were optimally immobilized at neutral pH and low ionic strength. All antigen preparations saturated the well with the same amount of protein. The vaccination schedule that advised a booster resulted in higher antibody titers, which were sustained over a longer period than the other schedule. CONCLUSIONS AND CLINICAL RELEVANCE: In the vaccination of cattle against C fetus, the ELISA we have developed may be used to evaluate serum antibody concentrations in response to various vaccines and vaccination schedules. Our results indicate that it is advisable to include a booster in the immunization protocol.     

Serum agglutinin titers against somatic and flagellar antigens of Campylobacter jejuni and isolation of Campylobacter spp in chickens

From June 1983 to June 1984, two hundred twenty-five 3- to 30-month-old chickens (hens) on 10 different farms were examined for Campylobacter spp. Watering trays and fly vectors also were examined for Campylobacter spp on 6 of the 10 farms. Campylobacter jejuni was isolated from fecal specimens from 64 hens (28.4%), C coli was isolated from 6 hens (2.7%), and C laridis was isolated from 9 hens (4%). The isolation rate of C jejuni was 6.7% to 46.7% for 9 of the 10 farms. On 2 farms, agglutinin titers greater than or equal to 1:40 against somatic and flagellar antigen of C jejuni were detected in hens from which the bacteria were isolated. Hens having titers greater than or equal to 1:40 against C jejuni or hens from which C jejuni had been isolated often occupied adjacent pens. Campylobacter jejuni was isolated from a watering tray on 1 farm and from fly vectors on 2 farms.     

IMMUNISATION OF CATTLE AGAINST VIBRIOSIS WITH VACCINES PREPARED FROM CAMPYLOBACTER FETUS SUBSP FETUS

Subcutaneous administration of vaccines prepared from cells of Campylobacter fetus subsp fetus strain A28 to heifers gave substantial protection against infertility due to C. fetus subsp venerealis strain B6. Strains A28 and B6 had different heat-stable antigens and conformed respectively to serotype B and serotype A of Berg et al (1971). The results suggested that the protective antigens were heat-labile antigens common to both strains. Although vaccines prepared from serotype B strains of C. fetus subsp fetus could be used to immunise cattle against vibriosis, the results did not suggest that their use in preference to those prepared from C. fetus subsp venerealis would offer any advantages.     

Serogroups of Campylobacter fetus and Campylobacter jejuni isolated in cases of ovine abortion

Of 38 aborted ovine fetuses from 23 sheep flocks 29 C. fetus subsp. fetus and 22 C. jejuni were isolated and examined biochemically and serologically for heat-stable antigens. Serologic examinations were carried out by passive haemagglutination test. In case of C. fetus subsp. fetus strains alkaline antigen extraction was used. Antisera to two serogroups of C. fetus and to Penner serotype reference strains 1 to 60 were produced in rabbits. Abortion was caused in 18 (78.3%) flocks by C. fetus subsp. fetus and in 5 (21.7%) flocks by C. jejuni. Six C. fetus subsp. fetus strains grew well at both 43 and 25 degrees C. With one exception all C. fetus subsp. fetus were resistant, whereas all 29 C. fetus subsp. venerealis strains were sensitive to 30 micrograms/ml cefoxitin and cefamandole. These two cephalosporins can be used to differentiate the two subspecies of C. fetus. Passive haemagglutination test using alkaline antigen extraction is a proper method for the examination of heat-stable antigens of both C. fetus subspecies. Out of 24 C. fetus subsp. fetus strains 13 belonged to serogroup A(01), and 11 to serogroup B(02). C. jejuni strains examined belonged to Penner serogroup 1 (6 strains), to serogroup 5 (4 strains) and to serogroup 8 (4 strains).     

Detection of Campylobacter antibodies in sheep sera by a Dot-ELISA using acid extracts from c. fetus ssp. fetus and c. jejuni strains and comparison with a complement fixation test

In this study, a dot-enzyme-linked immunosorbent assay (Dot-ELISA) was evaluated in comparison with a complement fixation test (CFT) for the detection of Campylobacter antibodies in sheep sera. Acid glycine extracts (AGE) of both Campylobacter fetus ssp. fetus and Campylobacter jejuni strains that had been isolated from the gall-bladder of slaughtered sheep was used as antigen in both tests. A total of 153 sheep sera from aborted (74) and slaughtered (79) sheep were examined by both Dot-ELISA and CFT. Twenty-two sera showed anti-complementary activity were not suitable for CFT. Of the 22 sera showing anti-complementary activity, two sera were found to be positive in Dot-ELISA. Eighty-eight (67.2%) of the remaining 131 sera were negative by both Dot-ELISA and CFT using AGE of both Campylobacter strains whereas 43 sera (32.8%) gave different reaction patterns in Dot-ELISA and CFT with the extracts of both Campylobacter strains. Twelve sera were positive by both tests using AGE of C. fetus ssp. fetus but CFT failed to detect antibodies in nine of these sera when AGE of C. jejuni was used. Twelve sera were positive by both tests only when AGE of C. fetus ssp. fetus was used. Eleven sera were positive only by CFT. Seven of these reacted only with the AGE of C. fetus ssp. fetus and four sera were positive by using AGE of both Campylobacter strains. The remaining eight sera were found to be positive only by dot-immunobinding assay either with the AGE of both Campylobacter strains or with the AGE of one of the Campylobacter strains. It is concluded that Dot-ELISA using AGE from C. fetus ssp. fetus could be employed for the detection of Campylobacter antibodies in sheep sera and the additional use of AGE from C. jejuni as antigen appeared not to be profitable for this purpose.     

Detection of bovine antibodies to the outer membrane of ruminal Bacteroides succinogenes by enzyme-linked immunosorbent assay (ELISA)

The enzyme-linked immunosorbent assay (ELISA) was used to detect bovine serum antibodies directed to the outer membrane antigen of a ruminal bacteria, Bacteroides succinogenes. The outer membrane antigen of B. succinogenes was highly reactive against homologous antiserum, compared with rabbit sera raised against B. ruminicola subsp. ruminicola, B. ruminicola subsp. brevis and Selenomonas ruminantium. The titers of sera from colostrum-deprived calves were negligible level, while those of sera from colostrum-fed calves were relatively high. The mean titer of sera from 10 day-old calves was significantly (p less than 0.01) higher than that of 40 day-old calves, and was significantly (p less than 0.01) lower than that of adult cattle. The mean titer of sera from dairy cows which fed high-roughage diet was higher than that of feedlot cattle which fed high-concentrate diet. These results suggest that the antibodies against the outer membrane antigen of B. succinogenes transfer to calves via the colostrum, and that the titers of cows are affected by the way of feed management.     

Occurrence and significance of different Campylobacter types in domestic animals in Hungary

Experiences, including results of original experimental work on Campylobacter fetus, C. jejuni and C. coli induced diseases of cattle, sheep, dogs, rabbits poultry and men in Hungary are reviewed. Out of 31 cases of abortion in cows 29 (93.5%) were causes by C. fetus subsp. venerealis and only one case each (3.2%) by C. fetus subsp. fetus and C. jejuni, respectively. Out of the 29 strains of C. fetus subsp. venerealis, 26 belonged to serogroup 01 (A) and only 3 to serogroup 02 (B). Campylobacter abortions in sheep flocks were caused in 18 cases (78.3%) by C. fetus subsp. fetus and in 5 cases (21.7%) by C. jejuni. The latter strains belonged to Penner's serogroup 1 (6 strains), 5 (4 strains) and 8 (5 strains), respectively. In scouring dogs 12.7% of the cases were caused by C. jejuni. The same pathogen caused diarrhoea also in young rabbits. Isolated strains belonged to serogroup 2. In cases of Campylobacter hepatitis of laying hens, egg production has been reduced by 8 to 15% for 2 to 3 weeks. Row poultry meat represents often the source of infection for men. The 32 strains of C. jejuni isolated from faecal samples of men affected with diarrhoea belonged to 12 serogroups.     

Biotin-streptavidin enzyme-linked immunosorbent assay for the detection of antibodies to Campylobacter jejuni and C. coli in chickens.

An enzyme-linked immunosorbent assay (ELISA) was developed in a homologous system with bacterial ultrasonic-treated proteins as the antigen and antisera from chickens infected orally and subcutaneously with the strain Campylobacter jejuni serovar 6 (CJ 6). The cut-off level was determined using antisera from non-infected specific-pathogen-free chickens up to the age of 10 weeks. The suitability of the ELISA system was verified using antisera taken from chickens orally infected at the age of 4 weeks with CJ 1, 6, 28 or 36 or with Campylobacter coli serovar 28 (CC 28). The development of antibodies was monitored up to 6 weeks post-infection (p.i.). Sera from chickens infected with CJ 1, 6, 36 or CC 28 contained specific antibodies to Campylobacter, whereas in those infected with CJ 28 no specific antibodies were found. Distinct cross-reactions were observed between CJ 6, 28 and CC 28 antigens and their antisera 6 weeks p.i., while poor cross-reactions were found with antisera to CJ 1 and 28. Antibodies to strains of all heterologous serovars were successfully detected with an antigen pool comprised of CJ 1, 6 and 36 antigens. In 11 out of the 12 field sera obtained from 5- and 9-week-old broiler chickens suffering from campylobacteriosis, high specific antibody titres to Campylobacter jejuni were found.     

Experimental production of infectious bovine keratoconjunctivitis: comparison of serological and immunological responses using pili fractions of Moraxella bovis.

The effect of vaccinating cattle and mice on the development of keratoconjunctivitis was studied. Cattle were vaccinated with whole cells, disrupted cells and pili fractions of three strains of Moraxella bovis. Mice were vaccinated with pili fractions of three strains. The resistance of all vaccinated animals was challenged with virulent cultures of M. bovis. In an attempt to correlate the response seen after vaccination and challenge with a pili fraction of M. bovis, vaccinated cattle and mice were grouped on the basis of signs of disease manifested and compared on the basis of serological responses. Serum samples were tested for antibodies by a gel diffusion precipitin test. A greater number of the sera of resistant cattle had antibodies to the homologous pili antigen than those of vaccinated nonresistant cattle. Cattle vaccinated with disrupted cells were not resistant to infectious bovine kerato-conjuctivitis and their sera lacked antibodies against the pili antigens. Vaccinated mice were more resistant to infectious bovine kerato-conjuctivitis and their sera lacked antibodies against the pili antigens. Vaccinated mice were more resistant to challenge exposure by homologous than heterologous cultures. A greater number of the sera of resistant mice had antibodies to pili antigens than nonresistant mice.     

Antibodies against Helicobacter felis in sera of cats and dogs.

Serum samples from 61 dogs and 49 cats were screened for circulating antibodies against Helicobacter felis by an enzyme-linked immunosorbent assay (ELISA) using sonicated bacteria as an antigen. To improve the specificity of the ELISA, sera were absorbed with Campylobacter jejuni subsp. jejuni H. pylori as well as H. felis. Sera from 26 dogs (43%) and 19 cats (39%) revealed clear positive absorbance readings determined as an optical density (OD) that was statistically significant above the OD mean value [P < 0.025 (one-tailed); log10]. The absorbance pattern of ELISA-positive sera corresponded to results obtained with bovine and human reference sera. Furthermore, a correlation between the immune response and results from histopathological examination of gastric specimens from 22 dogs was demonstrated. It could be shown that antibodies against H. felis in sera of cats and dogs can easily be detected using an ELISA. The diagnostic value of this test must be evaluated in further investigations.     

Pulsed-field gel electrophoresis typing of Campylobacter fetus subsp. fetus from sheep abortions in the Hawke's Bay region of New Zealand

AIM: To type Campylobacter isolates from sheep abortions from the Hawke's Bay region of New Zealand. METHODS: Campylobacter isolates were collected from aborted sheep fetuses from commercial farms in the Hawke's Bay region. Information on the Campylobacter vaccination status of flocks in the study was collected. Isolates were identified to species level using standard phenotypic tests, then typed using pulsed-field gel electrophoresis (PFGE). RESULTS: Eighty-one C. fetus subsp. fetus isolates were cultured from aborted sheep fetuses from 25 farms and four C. jejuni isolates were cultured from fetuses from three farms. The C. fetus subsp. fetus isolates were classified into six PFGE groups. A single pulsed-field type predominated amongst isolates from 19 of the 25 farms. The C. jejuni isolates comprised two types. CONCLUSIONS: A range of C. fetus subsp. fetus PFGE types was identified, and one type, B1, was found most frequently. Campylobacter fetus subsp. fetus was only isolated from samples from sheep that had not been vaccinated with C. fetus subsp. fetus vaccine that season.     

The indirect hemagglutination test for the detection of antibodies in cattle naturally infected mycoplasmas.

Stable mycoplasma antigens for the indirect hemagglutination test (IHA) were prepared employing glutaraldehyde treated sheep erythrocytes sensitized with Mycoplasma agalactiae subsp. bovis and Mycoplasma bovigenitalium antigens. Employing these antigens mycoplasma antibodies were detected in sera from cattle which had mastitic symptoms due to natural infection with either M. agalactiae subsp. bovis or M. bovigenitalium. A total of 200 cows from four herds were examined at varying intervals for the presence of M. agalactiae subsp. bovis and for the detection of antibody using growth inhibition and IHA tests. Mycoplasmas were isolated from 37 animals. Growth inhibiting antibody was detected from 56 of the 200 animals. In the IHA tests, antibody titer greater than or equal to 1:80 were detected in 148 animals, 76 of these having antibody titers greater than or equal to 1:160, while sera of 116 normal control animals had no growth inhibiting antibody and none had IHA antibody titers greater than 1:40. M. bovigenitalium was isolated from the milk of three of 26 animals in a fifth herd during an outbreak of mastitis. Growth inhibiting antibodies were demonstrated in the sera of ten of the 26 animals. However, the IHA test detected antibody titers of greater than or equal to 1:160 in 13 animals and of 1:80 in one of the 26 animals. To determine the specificity of the IHA tests, M. agalactiae subsp. bovis and M. bovigenitalium antigens were reacted with rabbit hyperimmune typing sera produced against 12 species of bovine mycoplasmatales. Homologous antisera showed IHA antibody titers of 1:1280 and 1:2560 against M. agalactiae subsp. bovis and M. bovigenitalium respectively, whereas heterologous antisera showed IHA antibody titers of less than or equal to 1:20. Also eight type-specific bovine antisera were reacted with M agalactiae subsp. bovis and M. bovigenitalium antigens in homologous and heterologous tests. Homoogous reactions showed IHA antibody titers greater than or equal to 1:320, whereas heterologous reactions showed IHA titers of less than or equal to 1:20. This IHA test promises to be useful for the detection of bovine mycoplasma antibodies in sera from cattle infected with M. agalactiae subsp. bovis or M. bovigenitalium. Thes test is sensitive, reproducible and specific and the technique is relatively simple and rapid. The antigens were stable for at least seven months.     

Serological distinction of bovine Salmonella carriers from vaccinated and acutely infected cows.

Identification of Salmonella carriers using lipopolysaccharide (LPS) ELISA serology in a Salmonella-infected herd requires distinction of chronically infected cattle from convalescent and vaccinated cows. Cows responding to Salmonella infection and vaccination produce titers to Salmonella LPS that overlap with the lower titers of some Salmonella carriers. The objective of this study was to determine if the LPS antigen specificity of the bovine humoral immune response to Salmonella LPS antigens differs following vaccination and acute and chronic Salmonella infection. The study focused on the nondiscriminatory area of Salmonella ELISA serology, specifically, peak-titered sera from Salmonella bacterin-vaccinated and experimentally infected cows and low-titered sera from Salmonella carriers. The LPS serogroup specificity of the IgG1 and IgG2 response following acute and chronic Salmonella serotype Dublin infection and Salmonella bacterin vaccination was evaluated using 5 Salmonella serogroup (B, D, E1, C3, and C1) LPS ELISA assays. IgG, titers of carriers, vaccinated, and acutely infected cows were predominantly O antigen specific. Similarly, the IgG2 titers of acutely infected cows were also O antigen specific. In contrast, Salmonella carriers produced an IgG2 response to each of the heterologous LPS antigens (B, E1, C3, and C1) examined. The results of this study indicate that the bovine IgG1 isotype response to Salmonella LPS is serogroup specific. Conversely, production of IgG2 antibodies to core Salmonella LPS antigens shared across Salmonella serogroups is a feature of chronic Salmonella infections.     

Campylobacter as the cause of diarrhea in calves]

The modified Preston medium allows the isolation of C. jejuni, C. coli and C. fetus subsp. fetus from intestinal samples of calves at an incubation temperature of 37 degrees C. In the first series of investigation, Campylobacter excretion in calves (n = 7) was followed up to the age of 4 months. In the first 4 days of life, these bacteria could not be detected in any of the animals. Thereafter first C. coli we found in all calves. In 4 animals, only strains of this species were isolated during the whole investigation period. In 3 animals C. fetus subsp. fetus could be detected repeatedly, however C. coli and sometimes C. jejuni were found, too. In the second series of investigation, isolation of Campylobacter from different parts of the gastrointestinal tract or organs was successful in 19 out of 25 diarrhoeal, moribund calves. 16 out of 19 positive animals harboured large amounts of these gramnegative bacteria in the distal jejunum and ileum. In 10 animals out of these 16, the germ colonized also the proximal jejunum and abomasum. From 6 calves, C. fetus subsp. fetus was isolated, and C. jejuni from 7 calves. C. coli was relatively rare. From the lymph nodes of the proximal and distal jejunum, Campylobacter (exclusively C. jejuni) were isolated from 5 animals. Due to the Campylobacter presence in the small intestine of diarrhoeal calves, a contribution of this bacteria within the pathogenesis of calf diarrhoea is possible. Final evaluation of their pathogenesis importance is only positive by means of virulence tests.     

The occurrence and characterization of Campylobacter spp. in silver gulls (Larus argentatus), three-toed gulls (Rissa tridactyla) and house sparrows (Passer domesticus)

Altogether 16 Campylobacter (C.) isolates could be recovered from 65 Herring gulls: 5 x C. laridis, 2 x C. jejuni biovar 1, 4 x C. jejuni biovar 2 and 5 x C. coli. Campylobacter spp. were isolated from 15 out of 51 samples from Kittiwakes: 2 x C. jejuni biovar 1 and 13 x C. laridis. All C. coli isolates grew on agar containing 1.5% NaCl. Two Campylobacter isolates from 50 House sparrows differed from all other isolates by a distinct beta-hemolysis and other phenotypic characteristics and could not be associated with a certain Campylobacter species. Epidemiological aspects and the possible role of the examined birds as a source of infection for man and domestic animals are discussed.     

Prokaryotic Expression of PEB1A Protein of Campylobacter jejuni and Establishment of an Indirect ELISA

In order to develop an indirect ELISA method to detect Campylobacter jejuni antibody, PEB1A gene of Campylobacter jejuni was cloned and amplified by PCR, the prokaryotic expression vector pET32a-PEBIA was constructed, and then transferred into the expression strain E.coli BL21 (DE3), and obtained about 47 ku of soluble protein. Western blotting result showed that the expressed recombinant protein had good biological activity, an indirect ELISA method for detecting antibody against Campylobacter jejuni was developed using expressed PEB1A protein as coating antigen,and detected its specificity, sensitivity, repeatability, respectively. The results showed that the established method for detection of Campylobacter jejuni antibody critical value was 0.3424. This method only specifically reacts with Campylobacter jejuni positive sera, and had no cross-reactivity with other antiserum and strong specificity. In addition, the coefficients of variations in both inter-and intra-assay were less than 5% indicating that it had good repeatability and stability. The establishment of this method could be applied to the rapid detection of Campylobacter jejuni in serum, and provided basis for further prevention and control of Campylobacter jejuni diarrhea.     

Biotin-Streptavidin Enzyme-Linked Immunosorbent Assay for the Detection of Antibodies to Campylobacter jejuni and C. coli in Chickens

An enzyme-linked immunosorbent assay (ELISA) was developed in a homologous system with bacterial ultrasonic-treated proteins as the antigen and antisera from chickens infected orally and subcutaneously with the strain Campylobacter jejuni serovar 6 (CJ 6). The cut-off level was determined using antisera from non-infected specific-pathogen-free chickens up to the age of 10 weeks. The suitability of the ELISA system was verified using antisera taken from chickens orally infected at the age of 4 weeks with CJ 1, 6, 28 or 36 or with Campylobacter coli serovar 28 (CC 28). The development of antibodies was monitored up to 6 weeks post-infection (p.i.). Sera from chickens infected with CJ 1, 6, 36 or CC 28 contained specific antibodies to Campylobacter, whereas in those infected with CJ 28 no specific antibodies were found. Distinct cross-reactions were observed between CJ 6, 28 and CC 28 antigens and their antisera 6 weeks p.i., while poor cross-reactions were found with antisera to CJ 1 and 28. Antibodies to strains of all heterologous serovars were successfully detected with an antigen pool comprised of CJ 1, 6 and 36 antigens. In 11 out of the 12 field sera obtained from 5- and 9-week-old broiler chickens suffering from campylobacteriosis, high specific antibody titres to Campylobacter jejuni were found.     

Evaluation of gamma radiation levels for reducing pathogenic bacteria and fungi in animal sewage and laboratory effluents.

Sewage samples collected from animal wastes and from effluents at an animal disease laboratory were inoculated with known numbers of pathogenic organisms and subjected to various doses of gamma radiation from a 60Co source. Surviving test organisms were quantitatively determined by selective and enrichment techniques. The experiment was modeled as a quantal assay in which probit analysis was applied to obtain D10 values. The D10 value represents the irradiating dose required to reduce the population by 90%. The D10 value ranged from 13.4 krad for Campylobacter fetus to 156.6 krad for Streptococcus faecalis in animal sewage. However, the D10 value for the laboratory effluent was generally lower. Based on the estimated D10 values, the rating of the test organisms in decreasing order of radiosensitivity appeared as follows: Brucella abortus, Campylobacter fetus subsp. fetus, Campylobacter jejuni, Campylobacter coli, Campylobacter laridis, Mycobacterium fortuitum, Aspergillus fumigatus, Salmonella muenster, Candida albicans, Clostridium difficile and Streptococcus faecalis. If the D5 and D1 values were utilized, this listing would be only slightly altered.     

空肠弯曲菌PEB1A蛋白的原核表达及间接ELISA方法的建立

为了建立检测血清中空肠弯曲菌（Campylobacter jejuni）抗体的间接ELISA方法,试验通过PCR扩增并克隆空肠弯曲菌PEB1A基因,构建原核表达载体pET32a-PEB1A,将该表达载体转化大肠杆菌BL21（DE3）感受态细胞,诱导表达获得约47 ku的可溶性目的蛋白,通过Western blotting证明所表达的重组蛋白具有良好的生物学活性。以纯化后的重组蛋白作为包被抗原,建立空肠弯曲菌抗体间接ELISA方法,对其特异性、敏感性、重复性进行检测。结果表明,本试验建立的空肠弯曲菌抗体间接ELISA检测方法临界值为0.3424,本方法仅与空肠弯曲菌阳性血清发生特异性反应,与其他抗血清无交叉反应,具有较强的特异性,批内、批间的重复性试验变异系数均<5%,具有较好的重复性和稳定性。该方法的建立可应用于血清中空肠弯曲菌抗体的快速检测,为进一步防制空肠弯曲菌腹泻提供依据。