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Campylobacter (C.) spp. are well recognised as the leading cause of bacterial food-borne diarrheal disease worldwide, with C. jejuni and C. coli as the most important species: C. coli is highly abundant in pigs and pork meat has often been implicated as a source for human infection. Intestinal colonisation of C. coli in pigs plays a role in carcass contamination during slaughter. Different pre-harvest intervention measures are proposed to reduce the C. coli burden in the porcine intestine. Among others, the use of probiotics to prevent or reduce the colonisation of intestinal pathogens is discussed. One aim of this study was to screen a variety of probiotics to evaluate their inhibitory activity against Campylobacter spp. in vitro. Therefore, cell-free culture supernatants of Lactobacillus spp., Bifidobacterium spp., Enterococcus (E.) faecium NCIMB 10415, and Escherichia coli Nissle 1917 were tested against C. jejuni and C. coli by a well-diffusion agar assay. Seven out of eleven Lactobacillus strains showed an inhibitory activity against at least one of the three tested Campylobacter strains. This antagonistic activity against Campylobacter spp. was caused by the production of organic acids that lowered the pH. Application with pH neutralised cell-free culture supernatants abolished this inhibitory effect. Other tested strains with probiotic properties showed no inhibitory activity against any Campylobacter spp. strain. The strain E. faecium NCIMB 10415 was chosen to test its inhibitory activity against C. coli in vivo. Twenty weaned piglets were allocated into two groups, a probiotic group and a control group.The diet of the probiotic group was supplemented with E. faecium NCIMB 10415 (10(9) cfu/kg feed, Cylactin) since weaning, whereas the control group received no probiotic treatment. All piglets were naturally colonised with C. coli. The excretion load of C. coli was monitored for 28 days. The results indicate that dietary supplementation of E. faecium NCIMB 10415 did not significantly affect C. coli excretion levels in pigs. In this study, E. faecium NCIMB 10415 showed no antagonistic activity against C. coli in vitro and in vivo and had no impact on the growth performance of weaned piglets.

Trichinella surveillance data in Germany show for indoor housed pigs hardly any cases. Nevertheless, obligatory testing is in place for each slaughtered pig. According to EU legislation systematic Trichinella testing can be replaced by a risk-based surveillance system if the risk of Trichinella infection in fattening pigs is negligible. The probability to detect a positive herd (herd sensitivity) was taken as an indicator for the effectiveness of the surveillance. Four different diagnostic methods: a) digestion method, b) E/S-ELISA, c) Western Blot, and d) ELISA sequentially combined with Western Blot, were compared regarding herd sensitivity and specificity for different herd and sample sizes and different levels of prevalence. In a further step three potential surveillance systems were compared with regard to their suitability for herd classification: (i) classical Trichinella examination by artificial digestion method, (ii) ELISA screening followed by classical Trichinella examination and (iii) ELISA screening followed by Western Blot. Results show that: 1) testing by the artificial digestion method (i) provides only low sensitivity of detection for positive herds at present levels of prevalence despite perfect specificity. 2) The ELISA alone provides a high sensitivity of detection even at low sample sizes but at the cost of a very low herd specificity, converging towards zero at increasing sample sizes. In surveillance system (ii), a large number of farms would still need to be tested with the classical digestion method, as they would be misclassified as positive by the ELISA. 3) The Western Blot as well as ELISA screening followed by Western Blot offer a high probability of correct herd classification. The latter diagnostic system appears to be the most suitable for a risk based surveillance (iii) and provides--despite reduced sample sizes--a higher probability for a correct herd classification than the traditional Trichinella examination.

Trichinellosis is a food-borne, zoonotic disease caused by a parasitic organism. Pork containing muscle larvae represents the most important source of human trichinellosis. In Germany, each slaughtered domestic swine is systematically sampled and examined for Trichinella spp. European Union legislation (EC (No.) 2075/2005) condones the approach of a risk-oriented meat inspection for Trichinella in pigs which is accompanied by monitoring programmes for pig holdings and reservoir animals. Here we discuss the current epidemiological situation of Trichinella in the sylvatic cycle in Germany and the implications for the implementation of risk-based sampling.

The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs.Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were orally infected with a porcine S. Infantis or S. Derby strain. Clinical and bacteriological parameters were monitored weekly during an observation period of 130 days after infection and serum samples were investigated in parallel with the respective ELISAs. Apparently, the LPS-based ELISA systems used in this study failed to recognize S. Infantis-infected pigs although those animals shed the pathogen in high amounts throughout the study until day 81 post infection (p. i.). In contrast, the isotype-specific Salmonella Typhimurium whole-cell-lysate based ELISA was capable of detecting Salmonella-infected pigs from day ten p. i. at all tested serotypes and revealed the highest sensitivity in detection of S. Infantis-infected pigs. Furthermore, it became apparent that the often used surveillance cut-off value of 40 OD% is not appropriate for intra-vitam detection of S. Infantis- and S. Derby-infected pigs. In contrast, the cut-off values of the ELISAs given by the suppliers result in considerable higher detection rates.

In order to evaluate suitability of Fluorescence Polarisation Assay (FPA) for serological Brucella diagnostic, 1739 samples of sera from cattle, pigs, sheep and goats (65 Brucella-positive, 960-negative and 714 false-positive sera) were investigated at a dilution of 1:10. The cut-off was adjusted by means of ROC analysis. Furthermore, the serum samples were examined for Brucella antibodies using SAT, CFT and ELISA and the results were evaluated regarding sensitivity and specificity. FPA, SAT, CFT and ELISA attained a sensitivity of 92.3, 98.5, 84.6 and 86.2%. In comparison, specificity varied with 87.8, 72.6, 92.5 and 85.8%, respectively. Accordingly, FPA is a suitable test for serodiagnosis of brucellosis.

Brucella (B.) canis was isolated from ejaculate of a 4-year old Korthals-Griffon male dog after occurrence of epididymitis and orchitis. Despite several trials of therapy with different antibiotics relapes occurred, with B. canis being isolated from ejaculate, blood and urine samples, respectively. Bacteriological examinations were added by serological testing over a period of about 1.5 years. During the study SAT serum titre steadily dropped from 1:200 to 1:50. By CFT, B. canis antibodies were detectable at the beginning with a titre of 1:320 and to the end of the study with titres between 1:80 and 1:160.

Internal organs of 74 racoon dogs originating from the eastern districts of the Federal Land Brandenburg were subjected to a complete helminthological dissection. In addition, samples of diaphragma muscles from 46 further animals were examined for Trichinella larvae. Altogether 3 trematode- (Alaria alata, Isthmiophora melis, Metorchis bilis), 3 cestode- (Mesocestoides sp., Echinococcus multilocularis, Taenia polyacantha) and 7 nematode species (Capillaria aerophila, C. plica, Trichinella spiralis, Uncinaria stenocephala, Molineus patens, Crenosoma vulpis, Toxocara canis) could be identified. Thereby, the racoon dog has a comparable helminth spectrum as well known in red foxes. Differences in the frequency of the occurrence of helminths in both hosts can be explained by different food preferences.

Brucella and Yersinia enterocolitca O:9 (Y.e.O:9) have antigenic determinants in common causing cross-reactions which interfere strongly in Brucella serology. Hoffmann (1988) observed cross-reactivity between Y.e.O:9, Y.e.O:5, and Y.e.O:6 and used an ELISA for the differentiation between Brucella- and Yersinia antibodies since Y.e.O:5 and Y.e.O:6 produced only low-level cross-reactions with Brucella antigen. The observations of Hoffmann were confirmed and led to the construction of an ELISA with 4 antigens. Sera from natural outbreaks of brucellosis and from artificial infections with Brucella and Y.e.O:9 were properly identifiable by this system. Furthermore, the test material has been used to measure the antibody avidity by a specially designed ELISA. This test produced a further divergence between specific and non-specific reactions.

In the last century already, Friedrich Albert Zenker and Rudolf Virchow have provided the essential prerequisites for the examination of pork for Trichinella in Germany. According to Directives 64/433/EEC and 77/96/EEC, this examination is still required in all member states of the European Union (EU) for trade between EU countries and for pork imported from third countries. According to Directive 64/433/EEC (Article 6, para 2), the examination of swine for Trichinella may be dispensed with if, on the basis of epidemiological studies, the stocks are found to be free from Trichinella and there is an efficient system of ante-mortem and post-mortem examination and control. However, it had been impossible to introduce these provisions into practice due to the fact that criteria were lacking. Therefore, the Scientific Veterinary Committee of the European Commission established a working group which has elaborated a concept for the certification of Trichinella-free pig stocks. The concept includes, inter alia, definitions of the essential components of "non-endemic area" and "Trichinella-free stock" and the requirement to be complied with for certification. Details are given on measures taken to control continued compliance with the certification requirements, the reporting and documentation system and the measures to be taken when trichinellosis is detected at a certified farm.

A modified E/S-ELISA based on the procedure described by Gamble et al. (1988) was used for the diagnosis of trichinellosis in the domestic pig. The results of screening the sera of 92 pigs experimentally infected with Trichinella larvae (T. spiralis, T. nativa) with different doses, confirmed that the E/S-ELISA is suitable for the serological detection of Trichinella-specific IgG. Although the serotest shows a high sensitivity especially in the case of a low infection rate, it can not be used as an alternative for traditional meat inspection methods because of its so called diagnostic window. On the other hand, this serotest is considered to be useful for herd monitoring. False-negative results prior to completed seroconversion (the diagnostic window) were in most cases encountered up to the 4th-5th week post infection (p.i.), depending on the infectious dose used. Due to the prolonged persistence of antibodies, it was possible to demonstrate Trichinella infections by serology for a relatively long period (at least 80 weeks p.i.). Predictably, all 960 swine sera from the field tested in the E/S ELISA were negative for Trichinella. Separation and staining of the E/S antigen in SDS-PAGE revealed altogether 4 major protein bands with molecular weights of 44-67 kD. The 44 kD band showed the most intense reaction in an immunoblot using Trichinella antibodies. In contrast to the E/S-antigen, in the immunoblot using the same defined sera, the protein bands of somatic antigen caused cross reactions with non specific antibodies, which would lead to false-positive results in the ELISA.