Type, areal extent and localization of carcass contaminations during industrial pig slaughter.

The aim of the study is to provide an up-to date overall evaluation of visual contamination occurring on the slaughter line in order to provide a basis for implementing contamination control measures and to the hygienic quality of the processes. For this purpose, 627 contaminated pig carcasses in an industrial slaughterhouse in north western Germany were examined in 2021 for its distribution of type, areal extent and localization of slaughter contamination. Prior to official meat inspection, two persons visually scanned dorsal and ventral surfaces of the eviscerated but not yet split pig carcasses from cranial to caudal and recorded types, areal extent and localization of the contamination. The main contamination type were intestinal contents, bile, stomach contents, tubular rail fat and "others", which mostly consisted of a reddish foam from the respiratory tract. 103 out of 627 contaminated animals showed more than one contamination, which leads to a total number of 754 contaminations detected. Intestinal contents accounted for almost half of all contaminations and "others" for 30%. Forelimb, back and ham together counted for 70% of the contaminated regions. The affected area was smaller than that of a one euro coin (diameter about 23 mm) in 86% of the cases.

Phenotypic antimicrobial resistance in Escherichia coli strains isolated from swine husbandries in North Western Germany - temporal patterns in samples from laboratory practice from 2006 to 2017.

BACKGROUND: Since 2011, antibiotic usage has decreased continuously in livestock in Germany. Whether this is accompanied by a reduction in bacterial antimicrobial resistance has not been proven so far. In this study 3054 Escherichia coli (E. coli) isolates from pigs which had suffered from disease on 2161 farms in North Western Germany were evaluated retrospectively from 2006 to 2017 for trends in their antimicrobial resistance pattern. Data were substantially related to the "pre-reduction period" and were therefore suggested as a basis for this task. Minimal inhibitory concentrations for selected antimicrobial substances were evaluated for E. coli strains isolated from different organs of diseased swine sampled for routine diagnostic. In total, 81% of E. coli were isolated from faeces or the gastrointestinal tract, 11% from the genito-urinary tract and 8% from other organs. Susceptibility testing and classification of isolates in accordance with clinical cut-offs followed the Clinical and Laboratory Standards Institute (CLSI). If no clinical cut-offs were available for the respective combination of species, substance and organ, other published clinical cut-offs were used. RESULTS: Differences in susceptibility patterns between isolates from the gastrointestinal and genito-urinary tract were found for most substances. Isolates from the genito-urinary tract were less frequently resistant to ampicillin, apramycin, colistin, neomycin, spectinomycin and tetracycline and more frequently resistant to enrofloxacin and florfenicol. A multifactorial logistic regression model revealed time-dependent decreases in frequency of resistant isolates for neomycin, spectinomycin and tetracycline. For colistin, the highest percentage of resistant isolates with 16.0% was found in 2015 followed by a decrease to the level of 2009-2010 in 2017. A decrease in frequencies of ampicillin-resistant isolates was dependent on the age-group and time period. Irrespective of the year, less than 15% E. coli isolates were resistant to apramycin, cephalosporins, colistin, enrofloxacin, florfenicol, gentamicin and neomycin. CONCLUSION: An overall time-dependent decrease in the percentage of resistant E. coli isolates was found for some substances. These data from diseased animals indicate an impact of a general reduction in antibiotic usage on development of bacterial antimicrobial resistance in the field and can support the decision-making of swine practitioners for treatment options in swine.

Effects of isoflavones on breast tissue and the thyroid hormone system in humans: a comprehensive safety evaluation.

Isoflavones are secondary plant constituents of certain foods and feeds such as soy, linseeds, and red clover. Furthermore, isoflavone-containing preparations are marketed as food supplements and so-called dietary food for special medical purposes to alleviate health complaints of peri- and postmenopausal women. Based on the bioactivity of isoflavones, especially their hormonal properties, there is an ongoing discussion regarding their potential adverse effects on human health. This review evaluates and summarises the evidence from interventional and observational studies addressing potential unintended effects of isoflavones on the female breast in healthy women as well as in breast cancer patients and on the thyroid hormone system. In addition, evidence from animal and in vitro studies considered relevant in this context was taken into account along with their strengths and limitations. Key factors influencing the biological effects of isoflavones, e.g., bioavailability, plasma and tissue concentrations, metabolism, temporality (pre- vs. postmenopausal women), and duration of isoflavone exposure, were also addressed. Final conclusions on the safety of isoflavones are guided by the aim of precautionary consumer protection.

Joint use of Disparate Data for the Surveillance of Zoonoses: A Feasibility Study for a One Health Approach in Germany.

Zoonotic diseases concern human and animal populations and are transmitted between both humans and animals. Nevertheless, surveillance data on zoonoses are collected separately for the most part in different databases for either humans or animals. Bearing in mind the concept of One Health, it is assumed that a global view of these data might help to prevent and control zoonotic diseases. In following this approach, we wanted to determine which zoonotic data are routinely collected in Germany and whether these data could be integrated in a useful way to improve surveillance. Therefore, we conducted an inventory of the existing data collections and gathered information on possible One Health surveillance areas in Germany by approaching experts through a scoping survey, personal interviews and during a workshop. In matching the information between the status quo for existing data collections and the possible use cases for One Health surveillance, this study revealed that data integration is currently hindered by missing data, missing pathogen information or a lack of timeliness, depending on the surveillance purpose. Therefore, integrating the existing data would require substantial efforts and changes to adapt the collection procedures for routine databases. Nevertheless, during this study, we observed a need for different stakeholders from the human and animal health sectors to share information to improve the surveillance of zoonoses. Therefore, our findings suggest that before the data sets from different databases are integrated for joint analyses, the surveillance could be improved by the sharing of information and knowledge through a collaboration of stakeholders from different sectors and institutions.

Low-level antimicrobial resistance of Enterobacteriaceae isolated from the nares of pig-exposed persons.

Extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-E) have recently emerged in livestock and humans. Therefore, this study assessed the carriage of Enterobacteriaceae in the anterior nares and associated antimicrobial resistance in pig-exposed persons. Nasal swabs were enriched in non-selective broth and then plated on MacConkey and ESBL-selective agars. Species was confirmed by matrix-assisted laser-desorption ionization-time-of-flight mass spectrometry (MALDI-ToF MS). Antimicrobial susceptibility testing was performed according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. Of 114 pig-exposed persons tested, Enterobacteriaceae were detected in the nares of 76 (66·7%) participants. The predominant species were Proteus mirabilis (n = 17, 14·9%), Pantoea agglomerans (n = 13, 11·4%), Morganella morganii (n = 9, 7·9%), Citrobacter koseri (n = 9, 7·9%), Klebsiella pneumoniae, Escherichia coli and Proteus vulgaris (each n = 8, 7·0%). ESBL-E were not detected. Of all isolates tested, 3·4% were resistant against ciprofloxacin, 2·3% against gentamicin, 23·9% against trimethoprim-sulfamethoxazole and 44·3% against tigecycline. Despite the high prevalence of ESBL-E in livestock, pig-exposed persons did not carry ESBL-E in their nares. This finding is important, because colonization of the nasal reservoir might cause endogenous infections or facilitate transmission of ESBL-E in the general population.

Epidemiological analysis of the dynamic and diversity of Salmonella spp. in five German pig production clusters using pheno- and genotyping methods: an exploratory study.

An exploratory study in five conventional pig production clusters was carried out to investigate the dynamic and diversity of Salmonella spp. within different production stages and sample site categories (pooled feces, direct and non-direct environment). Observing two production cycles per production cluster, a total of 1276 samples were collected along the pig production chain. Following a microbiological examination via culture, 2246 subcultures were generated out of 285 Salmonella positive samples and analysed by pheno- and genotyping methods. Based on a combination of serotyping, MLVA (multiple-locus variable-number tandem repeat (VNTR) analysis), PFGE (pulse-field gel electrophoresis) and MLST (multilocus sequence typing), an amount of 22.3% Salmonella positive samples were characterized in clonal lineages and its variants. Within each production cluster, one main clonal lineage could be identified and persisted over both production cycles with a large diversity of variants and a wide distribution in sample site categories and production stages. Results underline the importance of biosecurity with emphasis on the environment to prevent persistence and circulation of Salmonella within herds. Furthermore, the combined implementation of MLVA, PFGE and MLST with conventional culture techniques for isolate classification could be successfully applied as an effective and valuable tool for identifying similar pattern of Salmonella occurrence within pig production clusters.

Sporadic salmonellosis in Lower Saxony, Germany, 2011-2013: raw ground pork consumption is associated with Salmonella Typhimurium infections and foreign travel with Salmonella Enteritidis infections.

To investigate risk factors for sporadic salmonellosis, for each notified case four randomly selected population controls matched for age, sex and geographical region were interviewed via self-administered questionnaire. Conditional logistic regression analysis of 285 matched pairs revealed significant associations for raw ground pork consumption [odds ratio (OR) 6·0, 95% confidence interval (CI) 1·8-20·1], taking antacids (OR 5·8, 95% CI 1·4-24·5), eating meat outside the home (OR 5·7, 95% CI 2·2-14·6) and daily changing or cleaning of dishcloth (OR 2·1, 95% CI 1·2-3·9). Animal contact and ice cream consumption were negatively associated with salmonellosis (OR 0·5, 95% CI 0·2-1 and OR 0·3, 95% CI 0·1-0·6, respectively). S. Typhimurium infections were significantly associated with raw ground pork consumption (OR 16·7, 95% CI 1·4-194·4) and S. Enteritidis infections with having travelled abroad (OR 9·7, 95% CI 2·0-47·3). Raw egg consumption was not a risk factor, substantiating the success of recently implemented national control programmes in the poultry industry. Unexpectedly, hygienic behaviour was more frequently reported by cases, probably because they overestimated their hygiene precautions retrospectively. Although animal contact might enhance human immunocompetence, underreporting of salmonellosis by pet owners could have occurred. Eating raw pork products is the major risk factor for sporadic human S. Typhimurium infections in Lower Saxony.

Risk factors associated with sporadic salmonellosis in children: a case-control study in Lower Saxony, Germany, 2008-2011.

We conducted a case-control study based on 884 laboratory-confirmed sporadic Salmonella cases reported to the German infectious disease notification system. For controls, we recruited 510 rotavirus cases via the same system. Univariable and multivariable logistic regression analyses were performed separately for children aged 0-3 years and 4-14 years. In both age groups, the highest odds ratios (OR) were found for raw ground pork consumption [0-3 years: OR 8·6, 95% confidence interval (CI) 2·4-30·8; 4-14 years: OR 4·5, 95% CI 1·1-19]. Further risk factors were exposure to animals (OR 1·6, 95% CI 1·1-2·1), consumption of poultry (OR 1·5, 95% CI 1·1-2·1), food items containing eggs (OR 1·5, 95% CI 1·1-2) and black pepper (OR 1·7, 95% CI 1·1-3·5) in children aged 0-3 years, and consumption of uncooked pork sausage (OR 3·6, 95% CI 1·4-9·3) in children aged 4-14 years. This study highlights the significance of raw pork products ('Mett' in German) as risk factors for sporadic salmonellosis in children in Germany.

Zoonotic disease surveillance--inventory of systems integrating human and animal disease information.

Although 65% of recent major disease outbreaks throughout the world have a zoonotic origin, there is still a sharp division among the disciplines into the human and animal health sectors. In the last few decades, a global integrative concept, often referred to as 'One Health', has been strongly endorsed. Surveillance and monitoring efforts are major components for effective disease prevention and control. As human health and animal health are inextricably linked, it is assumed that a cross-sectoral data interpretation of zoonotic disease information will improve their prevention, prediction and control. To provide an overview of existing systems throughout the world which integrate information from humans and animals on zoonotic diseases, a literature review was conducted. Twenty projects were identified and described regarding their concepts and realization. They all vary widely depending on their surveillance purpose, their structure and the source of information they use. What they have in common is that they quite often use data which have already been collected for another purpose. Therefore, the challenges of how to make use of such secondary data are of great interest.

Statistical tools to improve assessing agreement between several observers.

In the context of assessing the impact of management and environmental factors on animal health, behaviour or performance it has become increasingly important to conduct (epidemiological) studies in the field. Hence, the number of investigated farms per study is considerably high so that numerous observers are needed for investigation. In order to maintain the quality and validity of study results calibration meetings where observers are trained and the current level of agreement is assessed have to be conducted to minimise the observer effect. When study animals were rated independently by the same observers by a categorical variable the exclusion test can be performed to identify disagreeing observers. This statistical test compares for each variable and each observer the observer-specific agreement with the overall agreement among all observers based on kappa coefficients. It accounts for two major challenges, namely the absence of a gold-standard observer and different data type comprising ordinal, nominal and binary data. The presented methods are applied on a reliability study to assess the agreement among eight observers rating welfare parameters of laying hens. The degree to which the observers agreed depended on the investigated item (global weighted kappa coefficients: 0.37 to 0.94). The proposed method and graphical description served to assess the direction and degree to which an observer deviates from the others. It is suggested to further improve studies with numerous observers by conducting calibration meetings and accounting for observer bias.

Herd-level risk factors for the seropositivity to Mycoplasma hyopneumoniae and the occurrence of enzootic pneumonia among fattening pigs in areas of endemic infection and high pig density.

The aim of the present study was to identify potential risk factors for the occurrence of enzootic pneumonia (EP) in herds situated in a region of high pig density, where a majority of herds is endemically infected with Mycoplasma hyopneumoniae. Between 2006 and 2010, overall 100 herds were enrolled in a case-control study. Data were collected through personal interview with the farmers, clinical examination of pigs and their environments, and serological testing for M. hyopneumoniae, swine influenza virus and porcine reproductive and respiratory syndrome virus. There were 40 case herds (coughing index high, seroprevalence high) with a mean coughing index of 4.3 and a seroprevalence of 86.6%. There were two control groups. Control group I consisted of 25 herds (coughing index low, seroprevalence low) with mean values of 0.7 and 11.2%, and 35 herds were allocated to control group II (coughing index low, seroprevalence high) where the mean coughing index was 0.9 and seroprevalence 86.3%. Case herds and control II herds had an increased age of piglets at weaning compared to control I herds. Any contact between fattening pigs of different age during restocking of compartments increased the risk for the occurrence of EP in a herd. Finally, farms that use living animals for the exposure to gilts during the acclimatization and farms that had increased number of weaned piglets per sow and year were less likely to test positive for M. hyopneumoniae and less likely to develop clinical symptoms of EP in fattening pigs.

Associations between host characteristics and antimicrobial resistance of Salmonella typhimurium.

A collection of Salmonella Typhimurium isolates obtained from sporadic salmonellosis cases in humans from Lower Saxony, Germany between June 2008 and May 2010 was used to perform an exploratory risk-factor analysis on antimicrobial resistance (AMR) using comprehensive host information on sociodemographic attributes, medical history, food habits and animal contact. Multivariate resistance profiles of minimum inhibitory concentrations for 13 antimicrobial agents were analysed using a non-parametric approach with multifactorial models adjusted for phage types. Statistically significant associations were observed for consumption of antimicrobial agents, region type and three factors on egg-purchasing behaviour, indicating that besides antimicrobial use the proximity to other community members, health consciousness and other lifestyle-related attributes may play a role in the dissemination of resistances. Furthermore, a statistically significant increase in AMR from the first study year to the second year was observed.

Campylobacter spp., Yersinia enterocolitica, and Salmonella enterica and their simultaneous occurrence in German fattening pig herds and their environment.

Campylobacter spp., Salmonella enterica, and Yersinia enterocolitica are common causes of foodborne infections in humans with pork as a potential source. Monitoring programs at farm level are, to date, only implemented for S. enterica, while epidemiological knowledge of the other two pathogens is still lacking. This study aimed to assess the pathogen load (in the pigs' environment) in fattening pig herds, their simultaneous occurrence, and the occurrence of Campylobacter spp. and Y. enterocolitica in herds in different Salmonella risk categories. In 50 fattening pig herds in northern Germany, four pooled fecal samples and 10 swab samples from the pigs' direct environment (pen walls, nipple drinkers), indirect environment (hallways, drive boards), and flies and rodent droppings were collected from each herd and submitted for cultural examination. Campylobacter spp. were detected in 38.1% of fecal, 32.7% of direct environment, 5.3% of indirect environment, and 4.6% of flies/pests samples collected, and Y. enterocolitica in 17.1, 8.1, 1.2, and 3.1% and S. enterica in 11.2, 7.7, 4.1, and 1.5%, respectively. For Campylobacter spp., Y. enterocolitica, and S. enterica, 80, 48, and 32% of herds were positive, respectively; 22 herds were positive for both Campylobacter spp. and Y. enterocolitica, 12 for Campylobacter spp. and S. enterica, and 7 for Y. enterocolitica and S. enterica. There was no significant association between the pathogens at herd level. Campylobacter spp. and Y. enterocolitica were found more often in samples from the low Salmonella risk category (odds ratio, 0.51; confidence interval, 0.36 to 0.73, and 0.3, 0.17 to 0.57), and this was also the case for Y. enterocolitica at herd level (odds ratio, 0.08; confidence interval, 0.02 to 0.3). This study provides evidence that the pigs' environment should be accounted for when implementing control measures on farms against Campylobacter spp. and Y. enterocolitica. An extrapolation from the current Salmonella monitoring to the other two pathogens does not seem feasible.

Longitudinal monitoring of extended-spectrum-beta-lactamase/AmpC-producing Escherichia coli at German broiler chicken fattening farms.

Antimicrobial resistance of Escherichia coli to modern beta-lactam antibiotics due to the production of extended-spectrum beta-lactamases (ESBL) and/or plasmid-mediated AmpC beta-lactamases (AmpC) represents an emerging and increasing resistance problem that dramatically limits therapeutic options in both human and veterinary medicine. The presence of ESBL/AmpC genes in commensal E. coli from food-producing animals like broilers may pose a human health hazard. However, there are no data available concerning the prevalence of ESBL/AmpC-producing E. coli in German broiler flocks using selective methods. In this longitudinal study, samples were taken from seven conventional broiler fattening farms at three different times within one fattening period. Various samples originating from the animals as well as from their direct environment in the barn were investigated for the occurrence of ESBL/AmpC-producing E. coli. Average detection levels of 51, 75, and 76% in animal samples collected during the three samplings in the course of the fattening period demonstrate a colonization of even 1-day-old chicks, as well as a continuous significant (P < 0.001) increase in prevalence thereafter. The detection frequencies in housing environmental samples were relatively high, with an increase over time, and ranged between 54.2 and 100%. A total of 359 E. coli isolates were characterized by PCR and partly via the disc diffusion method. This study shows that prevalence of ESBL/AmpC-producing E. coli increases during the fattening period of the broiler flocks examined. Both colonized day-old chicks and contaminated farm environments could represent significant sources of ESBL/AmpC-producing E. coli in German broiler fattening farms.

Subtype specific risk factor analyses for sporadic human salmonellosis: a case-case comparison in Lower Saxony, Germany.

With the intention to deepen the knowledge of the vertical transmission of particular subtypes of Salmonella enterica from "the stable to the table" a case1-case2 analysis in Lower Saxony, Germany, was conducted. The data collection was based on standardised telephone interviews with 1741 Salmonella case persons. Single-factor-analyses revealed statistically significant associations between S. Typhimurium infections and animal keeping (odds ratio (OR): 1.4; 95%-Confidence-interval (CI): 1.2-1.7), especially rodents (OR 1.5; CI 1.2-2.1), and with consumption of meat (OR 1.9; CI 1.3-2.8), raw ground pork (OR 3.0; CI 2.1-4.2) and uncooked pork sausage (OR 2.1; CI 1.6-2.9). The S. Typhimurium phage type DT 104 was associated most with consumption of uncooked pork sausage (OR 3.6; CI 1.3-8.5). Multiple logistic regression analyses confirmed the associations between S. Typhimurium infection and consumption of raw ground pork and with animal contact. The results circumstantiate the assumption of raw pork products still being a relevant source for S. Typhimurium infections in Germany. Therefore, it is recommended to intensify efforts to reduce salmonella infections caused by raw pork products. S. Enteritidis infection was associated statistically significantly with travelling abroad (OR 2.1; CI 1.6-3.3), consumption of raw tomatoes (OR 1.8; CI 1.5-2.1), dried herbs (OR 2.1; CI 1.0-1.8), and undercooked eggs (OR 1.3; CI 1.1-1.6) compared with other serovars. These results were confirmed in multiple logistic regression analyses, as well.

Risk factors associated with sporadic salmonellosis in adults: a case-control study.

In order to identify and assess recent risk factors for sporadic human infections with Salmonella enterica, we conducted a case-control study in Lower Saxony, Germany. The data collection was based on standardized telephone interviews with 1017 cases and 346 controls aged >14 years. Odds ratios were calculated in single-factor and multi-factor analyses for Salmonella cases and two different control groups, i.e. population controls and controls with rotavirus infection. Multi-factor analysis revealed associations between sporadic Salmonella infections for two exposures by both sets of controls: consumption of raw ground pork [adjusted odds ratio (aOR) 2·38, 95% confidence interval (CI) 1·27-4·44] and foreign travel (aOR 2·12, 95% CI 1·00-4·52). Other exposures included consumption of food items containing eggs (aOR 1·43, 95% CI 0·80-2·54), consumption of chicken meat (aOR 1·77, 95% CI 1·26-2·50), outdoor meals/barbecues (aOR 3·96, 95% CI 1·41-11·12) and taking gastric acidity inhibitors (aOR 2·42, 95% CI 1·19-4·92), all were significantly associated with respect to one of the two control groups. The impact of consuming food items containing eggs or chicken meat was lower than expected from the literature. This might be a consequence of Salmonella control programmes as well as increased public awareness of eggs and chicken products being a risk factor for salmonellosis. Efforts to reduce Salmonella infections due to raw pork products should be intensified.

Owner-collected swabs of pets: a method fit for the purpose of zoonoses research.

As part of the preparation of a large cohort study in the entire German population, this study examined the feasibility of cat and dog owners collecting nasal and oral swabs of their animals at home as a method of assessing exposure to zoonoses. In veterinary clinics in Hannover, Germany, 100 pet owners were recruited. Nasal and oral swabs of pets were taken by a veterinarian at the clinic and owners took swabs at home. Swabs were analysed regarding bacterial growth and compared (owner vs. vet) using Cohen's kappa and McNemar's test. The return rate of kits was 92%, and 77% of owners thought it unnecessary to have veterinarian assistance to swab the mouth. McNemar's test results: oral swabs 78% agreement with Gram-positive bacterial growth, 87% agreement with Gram-negative bacterial growth; with similar results for nasal swabs. Although sample quality differed, this method allowed the receipt of swabs from pets in order to obtain information about colonization with zoonotic pathogens.

Antibiotic susceptibility of Salmonella, Campylobacter coli, and Campylobacter jejuni isolated from Northern German fattening pigs.

This study was conducted to assess the antimicrobial susceptibility rate of Salmonella and Campylobacter spp. isolated from Northern German fattening pigs. From 540 lymph node samples, 16 Salmonella Typhimurium, 1 Salmonella Brandenburg, 37 Campylobacter coli, and 11 Campylobacter jejuni strains were isolated. Antibiotic susceptibility testing was carried out by the broth dilution method. The 14 tested antibiotics for Salmonella were ampicillin, cefotaxime, ceftazidime, chloramphenicol, ciprofloxacin, colistin, florfenicol, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim. The eight tested antibiotics for Campylobacter spp. were ampicillin, ampicillin-sulbactam (2:1), ciprofloxacin, erythromycin, gentamicin, nalidixic acid, sulfamethoxazole-trimethoprim (1:19), and tetracycline. In total, 93.7% (n = 16) of Salmonella Typhimurium, 75.7% (n = 37) of C. coli, and 54.5% (n = 11) of C. jejuni isolates were resistant to at least one of the tested antibiotics. Multiresistance to three antibiotics was observed in 75% of Salmonella Typhimurium, 16.2% of C. coli, and 0% of C. jejuni isolates. Pansusceptibility was detected in 6.3% of Salmonella Typhimurium, 24.3% of C. coli, and 45.5% of C. jejuni isolates. Multiresistance is defined as resistance to three or more antibiotics, and pansusceptibility is defined as not having resistance to any antibiotic. Regarding drugs of last resort--cefotaxime, ciprofloxacin, and nalidixic acid--resistance was not common among Salmonella (6.3%). The resistance rate of Campylobacter spp. to last-resort drugs--erythromycin, ciprofloxacin, and nalidixic acid--varied between species. The observed trend was not statistically significant. No C. coli isolates and few C. jejuni isolates (9.1%) were resistant to erythromycin. In contrast to C. jejuni, the C. coli isolates were more likely to be resistant to ciprofloxacin (9.1 and 18.9%, respectively) and nalidixic acid (0 and 13.5%, respectively). The same phenomenon was detected for tetracycline (27.3 and 62.2%, respectively), sulfamethoxazole (9.1 and 43.2%, respectively), and ampicillin (9.1 and 21.6%, respectively).

Main risk factors for Salmonella-infections in pigs in north-western Germany.

Salmonellosis is one of the major zoonotic, food-borne diseases, among others, caused by pig derived food products. As infected pigs are one of the main sources of the introduction of the bacterium into the food chain, scientific research in the last years has focussed on identifying risk factors for infection as well as developing mitigation strategies on this level of production. In order to update the knowledge of the German situation by incorporating recent changes in the German pig industry, a case-control study was set up to identify the key contributing risk factors for farms located in the western part of Lower Saxony, the region with the highest pig density in Germany. Based on an extensive and systematic literature search, a comprehensive questionnaire with 302 questions concerning such topics as personnel hygiene, animal management, biosecurity, feeding management as well as cleaning and disinfection routines was utilized in a face-to-face interview on 104 case and 67 control farms. Within a stepwise forward selection process the preliminary identified factors were grouped contextually, associations between variables were calculated and multivariable logistic regression models were conducted. Identified risk factors were: the moving of individual animals during the fattening period (OR 5.3, CI 95% 1.35-20.35), not having a separate transporter for different age groups (OR 11.4, CI 95% 1.94-66.18) and pigs having contact to other animals (OR 4.3, CI 95% 1.39-12.96). The following factors were identified as being protective: not cleaning the transporter (OR 0.2, CI 95% 0.05-0.72) and not having clean boots available (OR 0.2, CI 95% 0.07-0.64). While this study was able to identify some factors which influence the Salmonella-infection of a herd, overall the process of analysis showed that the control of Salmonella on farm is due to a series of individual factors and therefore remains extremely complex.