Fattening Pig Farms Research Articles

Prevalence and molecular characterization of C. pecorum detected in Swiss fattening pigs

Chlamydia (C.) pecorum, an obligate intracellular bacterial species commonly found in ruminants, can also occur in pigs. However, its significance as a potential porcine pathogen, or commensal, is still unclear. In a previous study (Hoffmann et al. 2015), mixed infections of C. suis and C. pecorum were detected in 14 Swiss fattening pig farms. Using these samples, we aimed to investigate the infection dynamics of C. suis and C. pecorum mixed infections in these farms. In addition, we analyzed the genetic diversity of Swiss porcine C. pecorum strains in relation to globally circulating strains. In total, 1284 conjunctival and rectal swabs from 391 pigs, collected at the beginning and end of the fattening period, were tested during the course of this study. We determined the bacterial loads of C. suis and C. pecorum using species-specific real-time PCR (qPCR) and compared these results to already existing DNA-microarray and Chlamydiaceae qPCR data. Overall, C. suis and Chlamydiaceae copy numbers decreased in the course of the fattening period, whereas C. pecorum copy numbers increased. No association was found between clinical signs (conjunctivitis, lameness and diarrhea) and the bacterial loads. Preventive antibiotic treatment at the beginning of the fattening period significantly lowered the chlamydial load and outdoor access was associated with higher loads. Proximity to the nearest ruminants correlated with increased C. pecorum loads, indicating that C. pecorum could be transmitted from ruminants to pigs. Multi-locus sequence typing (MLST) and major outer membrane protein (ompA) genotyping revealed two novel sequence types (STs) (301, 302) and seven unique ompA genotypes (1–7) that appear to form a specific clade separate from other European C. pecorum strains.

Environmental and economic consequences of pig-cooling strategies implemented in a European pig-fattening unit

Abstract The increased frequency of hot days due to climate change can potentially impair the environmental and economic performance of pig-fattening farms. Several pig-cooling strategies have been proposed to address these impacts, however their implementation is not always economically viable and the potential environmental-economic trade-offs not well understood. Here, we propose and implement a novel framework for environmental and economic evaluation of pig-cooling strategies in a whole farm context. We also demonstrate through a sensitivity analysis how such models can be integrated with projected climate data to investigate how climate change may affect the assessment of capital investments that are made over significant timescales. We considered two strategies implemented in a pig-fattening farm in south Sweden: pig-cooling with showers and with increased air velocity. Operation of the farm under non-cooling conditions was considered as the baseline system against which the analysis was conducted. We calculated whole-farm annual equivalent values (AEV) with the implementation of each strategy through a discounted cash flow analysis and annualised system environmental impact through a life cycle assessment. Both cooling strategies significantly reduced system environmental impact across all categories except water footprint. Acidification potential was reduced the most, exhibiting a −3.28% reduction with pig showers and −1.51% with increased air velocity. Farm profitability improved by +6.79% with showers and +3.37% with increased air velocity. Ambient temperature increase under non-cooling conditions significantly increased all impact categories with acidification being affected the most (+2.24%), and caused a −4.43% decrease in AEV. Both pig-cooling strategies mitigated these effects on system environmental performance. With increased air velocity we observed a +0.718% increase in acidification, while pig showers were the more resilient option exhibiting a +0.690% increase. The study represents a case-in-point for how to rationalise economically environmental management technologies in pig housing systems based on their cost-effectiveness in mitigating environmental impacts.

The Use of Antimicrobials in Italian Heavy Pig Fattening Farms.

Data on antimicrobial use (AMU) in heavy pig production (>150 kg) are limited. The aim of this study was to investigate the AMU in this production. Data from 2015 were collected for 143 fattening farms. The AMU was estimated through a treatment index per 100 days (TI100) using the defined daily dose animal for Italy (DDDAit). When possible, a comparison with the European Medicines Agency’s defined daily doses for animals (DDDvet) was performed. The median TI100 was 10.7 (range, 0.2–49.5). Group treatments represented 94.6% of overall consumption. The AMU calculated using DDDAit and DDDvet were strongly correlated (ρ = 0.976; p < 0.001). The AMU was negatively correlated with injectables use (ρ = −0.46, p < 0.001) and positively correlated with oral products (ρ = 0.21, p = 0.014), premixes (ρ = 0.26, p = 0.002), and mortality (ρ = 0.18; p = 0.027). Farm size was negatively correlated with AMU (ρ = −0.29, p < 0.001). Smaller farms were more frequently above the median TI100 (odds ratio = 2.3, 95% confidence interval = 1.2–4.7), suggesting that they may have lower biosecurity and management standards. The results of this study should provide useful insights for the development of an Italian monitoring system.

Ammonia emissions from different pig production scales and their temporal variations in the North China Plain

ABSTRACT Pig production systems in China are shifting from small to industrial scale. Significant variation in housing ammonia (NH3) emissions can exist due to differences in diet, housing design, and management practices. However, there is a knowledge gap regarding the impacts of farm-scale in China, which may be critical in identifying hotspots and mitigation targets. Here, continuous in-situ NH3 concentration measurements were made at pig farms of different scales for sows and fattening pigs over periods of 3–6 days during two different seasons (summer vs. winter). For the sow farms, NH3 emission rates were greater at the small farm (summer: 0.52 g pig−1 hr−1; winter: 0.21 g pig−1 hr−1) than at the large farm (summer: 0.34 g pig−1 hr−1; winter: 0.12 g pig−1 hr−1). For the fattening pig farms, NH3 emission rates were greater at the large farm (summer: 0.22 g pig−1 hr−1; winter: 0.16 g pig−1 hr−1) than at the small farm (summer: 0.19 g pig−1 hr−1; winter: 0.07 g pig−1 hr−1). Regardless of farm scale, the NH3 emission rates measured in summer were greater than those in winter; the NH3 emission rates were greater in the daytime than at the nighttime; a positive relationship (R2 = 0.06–0.68) was established between temperature and NH3 emission rate, whereas a negative relationship (R2 = 0.10–0.47) was found between relative humidity and NH3 emission rate. The effect of farm-scale on indoor NH3 concentration could mostly be explained by the differences in ventilation rates between farms. The diurnal variation in NH3 concentration could be partly explained by ventilation rate (R2 = 0.48–0.78) in the small traditional farms and by emission rate (R2 = 0.26–0.85) in the large industrial farms, except for the large fattening pig farm in summer. Overall, mitigation of NH3 emissions from sow farms should be a top priority in the North China Plain. Implications: The present study firstly examined the farm-scale effect of ammonia emissions in the North China Plain. Of all farms, the sow farm was identified as the greatest source of ammonia emission. Regardless of farm scale, ammonia emission rates were observed to be higher in summer. Ammonia concentrations were mostly higher in the large industrial farms partly due to lower ventilation rates than in the small traditional farms.

Biosecurity levels of pig fattening farms from four EU countries and links with the farm characteristics

Introduction of infectious agents (e.g. African swine fever) in a farm could have severe implications beyond the farm level. Among the solutions required to minimize the risk of disease introduction and spread, the strengthening of biosecurity is a priority. Yet, although the pig fattening (finishing) herds comprise 41.2% of the pig herds on a European level, the so far published studies on assessing biosecurity levels have focused on farrow-to-finish (closed) pig herds. In response, the aim of this study was to quantify the level of biosecurity of pig fattening farms in four European countries (Belgium, Poland, UK and Finland) and to study associations with management characteristics of the participating farms. The well-established Biocheck.UGent™ biosecurity scoring system was used and adapted to fattening pig farms. Biocheck.UGent™ provides risk-based scores to assess on-farm (external and internal) biosecurity ranging from 0 (worst) to 100 (best).Due to anonymity requirements, countries were coded in A, B, C and D; country codes do not correspond with the order of the countries above. Biosecurity and production data from 108 pig farms (country A: 9, country B: 38, country C: 51 and country D: 10) were collected during 2016. All differences between countries were assessed using Kruskal-Wallis H tests. External biosecurity had an overall median score of 66 (95% CI: 65–68) with differences (p ≤ 0.050) among countries (country A: 58.5, country B: 67.8, country C: 65.5 and country D: 75.3). Internal biosecurity had an overall median score of 71.6 (95% CI: 57.7–75.8) also with differences (p ≤ 0.050) among countries (country A: 51.4, country B: 45.5, country C: 84.1 and country D: 71.2).Using Spearman's correlation rank (rs) tests, non-significant correlation was seen between external and internal biosecurity (rs = 0.09, P = 0.340). Low to moderate negative correlations were seen between the internal biosecurity scores and either the farmer experience in keeping pigs (rs = −0.25, P = 0.008) or the farm size (rs = −0.31, P = 0.001). In conclusion, the present study informed of the biosecurity levels in these four countries and revealed links between biosecurity and farm-related parameters. Farm-specific investments and advice are jointly needed to further improve biosecurity in fattening farms.

High biosecurity and welfare standards in fattening pig farms are associated with reduced antimicrobial use

In order to reduce antimicrobial use in pig production, the consequences of insufficient biosecurity and welfare problems need to be known. This study aimed to investigate associations between the number of antimicrobial treatments per fattening pig, and biosecurity, indicators for animal welfare as well as the prevalence of lesions at slaughter. The data used in this study were extracted from the pig health and welfare classification system (Sikava), which gathers data on medicine usage, meat inspection, animal welfare and the condition of farm buildings from over 95% of pig production in Finland. The data were registered during years from 2011 to 2013. Upon antimicrobial prescription, information on the number of fattening pigs treated and the main reason for treatment was recorded. In addition, at least 4 times per year, pig farms registered in Sikava were visited by the farm veterinarian who assessed, among other things, biosecurity and indicators for animal welfare (air quality, condition of facilities, cleanliness, enrichment and stocking density). Finally, data from slaughterhouse inspections were collected (number of carcasses with joint infection, abscesses, lung lesions, pleurisy and liver lesions). For analysis, these datasets were aggregated at the farm level to a quarter of a year. During the studied period, the mean number of antimicrobial treatments per fattening pig per 3 months was equal to 0.09. The main reasons for antimicrobial treatments were musculoskeletal diseases, tail biting and respiratory disorders (42, 33 and 12% of diagnoses, respectively). The meat inspection scoring indicated that as much as 14.7% of all pigs had pleurisy, 5.3% liver lesions and 4.1% abscesses. A standard zero-inflated negative binomial model was used to identify factors associated with the number of antimicrobial treatments per pig. The count of antimicrobial treatments per pig increased with the size of a farm. Regardless of prevalence of lesions, farms with poor drinking equipment, insufficient enrichment and a combination of poor condition of pens and high stocking density were associated with an increased number of antimicrobial treatments for musculoskeletal diseases per pig. Problems with stocking density and enrichment were associated with the number of antimicrobial treatments for tail biting, although these results depended on prevalence of joint infections. Problems with air quality and the combination of poor cleanliness and poor condition of facilities were associated with increased number of antimicrobial treatments due to respiratory diseases. This study suggests that by improving biosecurity and welfare at pig farms, antimicrobial use can be reduced.

PRRSV eradication on large-scale fattening pig farms in Hungary between 2014 and 2019.

Eradication of porcine reproductive and respiratory syndrome virus (PRRSV) from the pig population of Hungary started in 2014 on the basis of the territorial principle. In order to reach this goal it was crucial to render each fattening unit free of this disease, since fattening units play a significant role in spreading the virus all over the country. In 2015, 188 out of 307 large-scale fattening farms (61.2%) kept PRRS-positive animals. The main source of infection of these farms was the import of PRRS-infected fattening pigs. The following methods were used during the eradication from 2017: (1) Only pigs coming from PRRS-free farms were allowed to be used for fattening in Hungary; (2) Quarantine of all herds for 60 days; (3) PCR test for PRRS 48 hours after the arrival of the prefattening animals; (4) Serological test for PRRS at the end of the quarantine period. If any diagnostic test gave even one positive result and the result was confirmed by another test, the stock had to be sold for slaughter within 15 days or placed outside Hungary, so that the infected stock would not compromise the PRRS status of that area. PRRSV eradication on large-scale fattening units applying all-in/all-out operation was relatively simple, using the depopulation-repopulation method. On permanently operating farms, the infected herd was sold from time to time, without having to be repopulated until the last delivery. After cleaning, disinfection and restocking, the repopulation was done with PRRS-free animals. As the eradication progressed over the years, a ban on the import of infected fattening pigs was imposed. As a consequence of these measures, by the end of 2018, Hungarian large-scale fattening farms became free of PRRS. Maintaining the national-level PRRS-free status of large-scale pig fattening units contributes to eliminating a significant cost factor from the Hungarian pork production industry, and opens the way for a significant reduction in antibiotic consumption as well.

Status quo analysis of noise levels in pig fattening units in Germany

This study was conducted within the MulTiViS-project consortium on multivariate animal welfare assessment. The aim of this investigation was to perform a status quo analysis of the noise level in fattening pig farms (n = 214) and to evaluate the suitability of noise as an animal welfare indicator. In 755 conventional fattening compartments, noise measurements were carried out for one minute at animal height using the Acoustic Analyser XL2, including microphone M2210 (NTI Audio, Schaan, Liechtenstein). In addition, various animal health and environmental factors of 33,668 pigs were recorded in randomly selected pens (n = 1,668) of these compartments. The mean equivalent noise level was 70.2 ± 5.2 dB (min 52.5, max 92.4 dB). Noise levels in compartments housing older pigs were higher (72.0 ± 5.2 dB) than those in compartments housing younger pigs (68.5 ± 4.7 dB, ***P < 0.001). Compartments in which the pigs were fed liquid feed were louder (70.3 ± 4.1 dB) than compartments with dry feed (67.5 ± 6.9 dB, ***P < 0.001). Slightly more noise was caused by partially slatted floors (70.3 ± 6.7 dB) compared to fully slatted floors (70.2 ± 5.0 dB, **P < 0.01), whereas straw bedding tended to reduce the noise level. In addition, the noise level in diffuse fresh air systems was lower (66.7 ± 5.1 dB, **P < 0.01) than in all other ventilation systems. There were no statistical associations identified between animal health factors (e.g. tail biting, ear biting, superficial skin lesions and Bursa auxiliaris) and noise levels. The present study provided useful indications on the status of the noise level in fattening compartments.

Characterization of VIM-1-Producing E. coli Isolated From a German Fattening Pig Farm by an Improved Isolation Procedure.

A few reports indicate that livestock might represent a new reservoir for carbapenemase-producing Enterobacteriaceae (CPE). In 2015, VIM-1-producing Escherichia coli were detected at slaughter in colon contents of animals from a German fattening pig farm within the national monitoring on ESBL-producing E. coli. In this study, pooled faces samples from pigs, as well as samples from the barn surrounding environment of this fattening farm were taken, to evaluate the dissemination of CPEs. Several modifications of the culture-dependent detection procedure were investigated for their potential to improve the sensitivity of the CPE isolation method. The current reference procedure was adapted by adding a real-time PCR pre-screening and additional enrichment steps. It was possible to isolate 32 VIM-1-producing E. coli from four fecal samples of three different barns using two serial enrichment steps in combination with real-time PCR and selective agar plates. By genetic typing, we confirmed the presence of two E. coli clonal lineages circulating on this particular farm: one was harboring the blaVIM–1 on an IncHI2 plasmid while the second lineage carried the gene on the chromosome. Despite its different locations, the blaVIM–1 gene was harbored on a class 1 integron in both clonal lineages. Whole-genome sequencing revealed that the VIM-1-carrying plasmids exhibited only slight variability in its compositions and sizes. We assume that the prevalence of CPEs in animal production in Germany and other European countries might be underestimated and there is a concern of further spread of VIM-1-producing bacteria in German livestock and food.

Coupling crop and bio-economic farm modelling to evaluate the revised fertilization regulations in Germany

The German Fertilization Ordinance, implementing mainly the EU Nitrates Directive, was revised in 2017. We couple the bio-economic farm model FarmDyn and the crop system modelling framework SIMPLACE to assess the environmental and economic impact of the revised ordinance. The analysis focuses on specialized pig fattening and arable farms in the federal state of North Rhine-Westphalia. Most dominant farm types are derived from a farm typology based on the German Farm Structure Survey 2016. Following the revised ordinance, a farm type representing pig farms with a high stocking density lowers its emissions from 50 to 38 kg nitrate (NO3−) nitrogen ha−1 and 18 to 8 kg ammonia (NH3) nitrogen ha−1 from manure application. Compliance costs are 2.32 Euro (€) pig−1 and are mainly caused by the need to export manure to meet the stricter nutrient surplus thresholds. A pig farm type with lower stocking density mainly adapts to the compulsory use of low-emission manure application techniques, resulting in almost constant NO3− leaching, a NH3 reduction from manure application of 13 to 9 kg NH3- nitrogen ha−1, and compliance costs of 0.42 € pig−1. The two assessed arable farm types, which start to import manure under the revised ordinance, can lower costs by 109 and 118 € ha−1. However, manure import increases NO3− leaching and NH3 volatilization. Our results show that intensive pig farms realize a high emission reduction and lose a relevant share of their standard gross margin when complying with the revised ordinance. However, farm types with low stocking density, representing a high share of the pig farms in the study area, show little or no changes in costs and emissions. These findings are relevant for efficient enforcement and targeted support measures. Furthermore, the import of manure on arable farms comprises the danger of regional pollution swapping, which policymakers should address by complementary measures. Future research should focus on improving the data base for crop modelling and on scaling-up the farm model to the regional scale to directly link emission changes and environmental targets.

MRSA in swine, farmers and abattoir workers in Southern Italy

Methicillin-resistant Staphylococcus aureus (MRSA) is an important medical issue, since it causes serious and sometimes fatal infections in humans. Intensively reared swine may serve as reservoirs for MRSA that can infect swine workers, and also consumers (via contaminated meat). In this study, MRSA strains were isolated from 55 of the 85 (64.7%) intensive pig farms surveyed, and prevalence was greater on pig fattening farms than on breeding farms. In addition, we included in the study 63 foreign pigs imported for slaughter. Overall, the prevalence of MRSA in the 418 sampled swine was 59.1%; 12 genotypes were identified among the isolates; ST398 (96.4%) was most prevalent, followed by ST97 (2%), ST9 (0.8%) and ST1 (0.8%). MRSA isolates were also detected in 26 (17.3%) of the 150 operators included in the study; the genotypes detected were ST398 (85%), ST9 (7.6%), ST5 (3.8%) and ST1 (3.8%). All the strains were pvl negative and pia positive. Both swine and human strains displayed a multi-resistance pattern, and almost all were resistant to tetracycline. The results obtained in this study confirm the high prevalence of MRSA in swine reared and slaughtered in Italy, and underline the public health risk linked to the spread of antimicrobial-resistant Staphylococcus aureus among intensively reared pigs.

Assessment of the feasibility of serological monitoring and on-farm information about health status for the future meat inspection of fattening pigs

Current macroscopic meat inspection cannot detect the most common pork-borne pathogens (Salmonella spp., Yersinia enterocolitica and Toxoplasma gondii). Furthermore, food chain information (FCI) may not provide sufficient data for visual-only inspection, which is supposed to be the common way of inspection of pigs in the European Union. Our observational study aimed to evaluate the serological monitoring and the clinical evaluation of on-farm health status of pigs and assess the feasibility of these data as part of the FCI in meat inspection. We studied the serological status of Salmonella spp., Yersinia spp. and T. gondii in pigs during the fattening period. Additionally, we evaluated the association between on-farm health status and meat inspection findings. On 57 indoor fattening pig farms in Finland, we collected blood samples (mean of 20 pigs/farm) and assessed the on-farm health (coughing, tail biting, lameness) at the end of the fattening period. We visited 34 of these farms also at the beginning of the fattening for sampling and on-farm health evaluation of the same pigs. Meat inspection results were obtained after slaughter for all 57 farms. Salmonella seroprevalence was low at the end of the fattening period: it was 17.6%, 10.6% or 1.9%, with the cut-off values of OD15% (recommended by the test manufacturer), OD20% (used by Danish monitoring programme) and OD40% (used by German monitoring programme), respectively. The overall seroprevalence of Salmonella spp. and Yersinia spp. increased significantly (P < 0.001) during the fattening period (from 8.1% to 17.2% and from 30.3% to 72.3%, respectively), while the seroprevalence of T. gondii remained low (<1%). The within-farm seroprevalences of Salmonella spp. and Yersinia spp. differed significantly between the farms and this farm-level serological data could be used as FCI for risk-based decisions to improve food safety. Such potentially feasible decisions could include additional carcass testing, carcass decontamination, carcass processing, slaughtering arrangements and improved biosecurity measures at the farm. However, risk mitigation targets and procedures must be carefully adjusted for each pathogen regarding also economic aspects. Tail biting observed on farm was associated with partial carcass condemnations and arthritis at slaughter. This information could be included in the FCI and used when making decisions regarding meat inspection procedure: visual-only or additional inspections.

Assessing the welfare level of intensive fattening pig farms in Germany with the Welfare Quality® protocol: does farm size matter?

AbstractThe housing condition of pig (Sus scrofa) fattening farms are increasingly receiving criticism, because they are associated with impaired animal welfare. Consumers view the increase in farm sizes critically, even though scientifically based knowledge on the relationship between farm size and welfare is still limited. Therefore, the aim of this study was to assess the welfare level of conventional fattening pig farms in Germany and to evaluate the relationship between farm size and animal welfare level. In total, the Welfare Quality® protocol (WQ) for pigs was applied on 60 farms. Farms were classified according to their size into small (&lt; 1,500 pigs per farm), medium (1,500-3,000 pigs per farm) and large (&gt; 3,000 pigs per farm). Independent of the farm size, the overall WQ classifications ‘excellent’ and ‘not classified’ were not recorded in any of the farms, while ‘enhanced’ and ‘acceptable’ was achieved by 80 and 20% of the farms, respectively. Farm sizes had no effect on any of the four principles ‘good feeding’, ‘good housing’, ‘good health’ or ‘appropriate behaviour’. Overall, moderate bursitis (35%) was found to be the most prevalent indicator of welfare-related problems. However, it did not differ between farm sizes. Another highly prevalent indicator, moderately soiled body, increased from 11.1% in small-to 20.8% in large-sized farms. In conclusion, our findings show that none of the farm sizes were superior in terms of animal welfare. Overall, acceptable or enhanced scores were achieved for many of the criteria, however the need for improvement in other criteria such as ‘expression of other behaviour’ and ‘positive emotional state’, was clear.

Association of farm-related factors with characteristics profiles of extended-spectrum β-lactamase- / plasmid-mediated AmpC β-lactamase-producing Escherichia coli isolates from German livestock farms

Resistance to β-lactam antibiotics, including third-generation cephalosporins, is of major concern for animal and human health. In this study, extended-spectrum β-lactamase (ESBL) / plasmid-mediated AmpC (pAmpC) β-lactamase -producing Escherichia coli isolates from German livestock farms were characterised and associations of these isolate characteristics with farm-related factors were investigated across different types of livestock.A total of 469 isolates originating from 150 farms (34 broiler farms, 38 fattening pig farms, 43 dairy cattle farms, 35 beef cattle farms) was included in the analyses. ESBL-gene family, phylogroup and phenotypic antimicrobial susceptibility for several antimicrobial agents were determined. This data was used to define different profiles characterising the isolates. Multivariate analyses using a distance-based non-parametric approach were performed to investigate associations between the profiles of the isolates and farm-related factors (e.g. management, husbandry, and environment of the farms).Co-occurrence of ESBL-gene families were not found in any of the isolates analysed. Sixty-eight percent of the isolates carried blaCTX-M variant genes. The frequency of phylogroups was as follows: A (55%), B1 (35%), D (17%) and B2 (3%). The most frequent phenotypic non-wildtype profile was non-wildtype status of solely cefepime (27%). Profiles of isolates from broilers differed substantially from those of other isolates. Associations between farm-related factors and characteristics profiles differed, depending on the isolate characteristics included in the analyses. Some factors describing the farm environment, like waterfowl in the surrounding of the farm, were associated with all tested profiles.The epidemiological method applied defines distances between isolates on basis of isolate characteristics data and is capable of analysing associations between isolate characteristics and epidemiological factors. As additional data, such as plasmid characteristics, gene type, or sequence information could be included in future studies, the method is suitable to identify points of action to reduce the occurrence of antimicrobial resistant bacteria.

Evaluating the Antibiotic Susceptibility of Chlamydia - New Approaches for in Vitro Assays.

Pigs are the natural hosts of Chlamydia suis, the only Chlamydia species known to spontaneously acquire homotypic resistance conferred by a class C tetracycline resistance gene. Various susceptibility assays have existed for several years, but there is no widely accepted, standardized assay to determine chlamydial antibiotic susceptibility. In this study, we developed new approaches to determine the in vitro susceptibility of Chlamydia to different antibiotics in view of existing protocols. Specifically, the minimal inhibitory concentration (MIC) is based on a consensus of both inclusion number reduction and alteration of inclusion size and morphology upon antibiotic exposure. In addition to these, we employed a recovery assay, allowing observation of the chlamydial response to drug removal and subsequent recovery, as compared to both continued exposure and to the unexposed control. We propose a simple and fast screening method to detect tetracycline resistant C. suis strains within 2 to 3 days with minimal use of consumables. For proof of principle, we evaluated the susceptibility of three C. suis field strains and the reference strain S45/6 to tetracycline, sulfamethoxazole, and penicillin, antibiotics commonly used to prevent respiratory and gastrointestinal diseases on fattening pig farms. We found that tetracycline sensitive strains can easily be distinguished from resistant strains using the evaluation parameters proposed in this study. Moreover, we report that S45/6 is sensitive to sulfamethoxazole while all evaluated C. suis field strains showed some degree of sulfamethoxazole resistance. Finally, we confirm that Penicillin G induces the chlamydial stress response in all evaluated C. suis strains.

Connecting Different Data Sources to Assess the Interconnections between Biosecurity, Health, Welfare, and Performance in Commercial Pig Farms in Great Britain.

This study aimed to provide an overview of the interconnections between biosecurity, health, welfare, and performance in commercial pig farms in Great Britain. We collected on-farm data about the level of biosecurity and animal performance in 40 fattening pig farms and 28 breeding pig farms between 2015 and 2016. We identified interconnections between these data, slaughterhouse health indicators, and welfare indicator records in fattening pig farms. After achieving the connections between databases, a secondary data analysis was performed to assess the interconnections between biosecurity, health, welfare, and performance using correlation analysis, principal component analysis, and hierarchical clustering. Although we could connect the different data sources the final sample size was limited, suggesting room for improvement in database connection to conduct secondary data analyses. The farm biosecurity scores ranged from 40 to 90 out of 100, with internal biosecurity scores being lower than external biosecurity scores. Our analysis suggested several interconnections between health, welfare, and performance. The initial correlation analysis showed that the prevalence of lameness and severe tail lesions was associated with the prevalence of enzootic pneumonia-like lesions and pyaemia, and the prevalence of severe body marks was associated with several disease indicators, including peritonitis and milk spots (r > 0.3; P < 0.05). Higher average daily weight gain (ADG) was associated with lower prevalence of pleurisy (r > 0.3; P < 0.05), but no connection was identified between mortality and health indicators. A subsequent cluster analysis enabled identification of patterns which considered concurrently indicators of health, welfare, and performance. Farms from cluster 1 had lower biosecurity scores, lower ADG, and higher prevalence of several disease and welfare indicators. Farms from cluster 2 had higher biosecurity scores than cluster 1, but a higher prevalence of pigs requiring hospitalization and lameness which confirmed the correlation between biosecurity and the prevalence of pigs requiring hospitalization (r > 0.3; P < 0.05). Farms from cluster 3 had higher biosecurity, higher ADG, and lower prevalence for some disease and welfare indicators. The study suggests a smaller impact of biosecurity on issues such as mortality, prevalence of lameness, and pig requiring hospitalization. The correlations and the identified clusters suggested the importance of animal welfare for the pig industry.

Occurrence of dysentery-like diarrhoea associated with Brachyspira suanatina infection on a German fattening pig farm

The anaerobic intestinal spirochaete Brachyspira (B.) suanatina was first described in 2007 but since then no further isolates have been reported from pigs. Accordingly, when the species was validly published...

Serological detection of Ascaris suum at fattening pig farms is linked with performance and management indices

The aim of the present study was to determine the association between the presence of Ascaris suum at fattening pig farms, using different serological methods and the percentage of affected livers at slaughter, with performance and management indices. In total, 21 fattening pig farms from the North of Spain were included in the study. Serum samples were collected from pigs at slaughter and analysed for the presence of anti-Ascaris antibodies. For this, two different ELISAs were used. The first was based on the antibody recognition of the A. suum haemoglobin (As-Hb) molecule whereas the second test used the total extract of A. suum lung stage L3. The serological results were subsequently correlated with the percentage of condemned livers at slaughter, management practices and technical performance parameters including average daily gain (ADG) and feed conversion ratio (FCR). According to the data from the slaughterhouse, 12 out of the 21 farms had livers condemned due to liver white spots. A total of 10 farms (48%) had an average optical density ratio (ODr) exceeding the test cutoff when the As-Hb ELISA was used. This number increased to 18 farms (81%) when using the As-Lung-L3 ELISA. The average ODr of the farms on both ELISAs correlated positively with the percentage of affected livers (P<0.01). Only the average ODr values obtained with the As-Lung-L3 ELISA were positively correlated with the FCR (P<0.01). No correlation was found between percentage of affected livers or serology and the ADG. In relation to management practices, farms with greater than or equal to 50% slatted flooring and that applied the ‘all-in/all-out’ flow system showed a lower percentage of liver condemnations (P<0.01), lower average ODr results on the As-Lung-L3 ELISA (P<0.05) and lower FCR (P<0.01) compared with those with less than 50% slatted flooring. This study emphasizes that serology is a promising diagnostic tool for diagnosing ascariasis at fattening pig farms. It also supports earlier findings that the presence of A. suum can have a significant negative impact on farm productivity and that stable infrastructure or management practices can have a considerable impact on the control of this parasite.

Molecular analysis of three Clostridium difficile strain genomes isolated from pig farm-related samples

Clostridium difficile is an anaerobic spore-forming bacillus that usually causes gastrointestinal disorders in man and other animal species. Most of the strains isolated from animals are toxigenic being the virulent ribotype (RT) 078 predominant in several animal species. Although C. difficile is pathogenic to both humans and animals, there is no direct evidence of zoonosis. Deep genome sequencing provides sufficient resolution to analyse which strains found in animals might be related to human pathogens. So far, there are only a few fully sequenced genomes of C. difficile strains isolated from domestic and wild animals. Using Illumina technology, we have sequenced the genome of three isolates; a strain isolated from the vagina of a sow (5754), one from rat (Rattus spp) intestinal content (RC10) and a third one isolated from environmental rat faeces (RF17). Both, rat and rat faeces were sampled in fattening pig farms. Our study reveals a close genetic relationship of two of these isolates with the virulent strain M120 (RT078) isolated from a human patient. The analysis of the sequences has revealed the presence of antibiotic resistance genes, mobile elements, including the transposon linked with virulence Tn6164, and the similarity of virulence factors between these isolates and human strains. This is the first study focused on the sequencing of C. difficile genomes obtained from wild animals like rats, which can be considered as potential reservoirs for humans and other animal species. This study can help to understand the genome composition and epidemiology of this bacterium species.

Investigation of potential risk factors for the occurrence of Escherichia coli isolates from German fattening pig farms harbouring the mcr-1 colistin–resistance gene

Within the scope of a cross-sectional investigation on fattening pig farms conducted in 2011 and 2012, 48 fattening farms in different agricultural regions of Germany were sampled. Primary cultures of boot swabs and collective faecal samples were stored at −80 °C and screened for the presence of the mcr-1 colistin–resistance gene. The laboratory results were linked to farm–related data collected via questionnaire. Logistic regression models were used to investigate the association between occurrence of mcr-1 and farm–related data. Escherichia coli carrying the mcr-1 gene were isolated from 26 of 216 (12.0%) mixed bacterial cultures originating from 12 of 48 (25.0%) farms. Results of the logistic regression analyses indicate that the transmission between pigs or their direct environment is crucial for the occurrence of these resistant bacteria. However, there was no statistically significant association between antimicrobial use and the occurrence of the mcr-1 gene.