Pig Fattening Research Articles

Automatically detecting pig position and posture by 2D camera imaging and deep learning

Prior livestock research provides evidence for the importance of accurate detection of pig positions and postures for better understanding animal welfare. Position and posture detection can be accomplished by machine vision systems. However, current machine vision systems require rigid setups of fixed vertical lighting, vertical top-view camera perspectives or complex camera systems, which hinder their adoption in practice. Moreover, existing detection systems focus on specific pen contexts and may be difficult to apply in other livestock facilities. Our main contribution is twofold: First, we design a deep learning system for position and posture detection that only requires standard 2D camera imaging with no adaptations to the application setting. This deep learning system applies the state-of-the-art Faster R-CNN object detection pipeline and the state-of-the-art Neural Architecture Search (NAS) base network for feature extraction. Second, we provide a labelled open access dataset with 7277 human-made annotations from 21 standard 2D cameras, covering 31 different one-hour long video recordings and 18 different pens to train and test the approach under realistic conditions. On unseen pens under similar experimental conditions with sufficient similar training images of pig fattening, the deep learning system detects pig position with an Average Precision (AP) of 87.4%, and pig position and posture with a mean Average Precision (mAP) of 80.2%. Given different and more difficult experimental conditions of pig rearing with no or little similar images in the training set, an AP of over 67.7% was achieved for position detection. However, detecting the position and posture achieved a mAP between 44.8% and 58.8% only. Furthermore, we demonstrate exemplary applications that can aid pen design by visualizing where pigs are lying and how their lying behavior changes through the day. Finally, we contribute open data that can be used for further studies, replication, and pig position detection applications.

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.

Acceptance and Feasibility of a Guideline for the Animal Welfare Assessment of Fattening Pigs from Farmers' Point of View.

Simple SummaryThe German Association for Technology and Structures in Agriculture has published the guide “Animal Welfare Indicators: Practical Guide—Pigs”, which is intended to help farmers to evaluate the welfare of pigs. Crucial for the acceptance of the guide by farmers is a high degree of feasibility of the contained indicators as well as the proposed procedure for recording them. To evaluate this, 40 farmers keeping fattening pigs were interviewed. The result is that, apart from faecal soiling and tail length, all the other eleven indicators are accepted for the assessment of fattening pig welfare by a majority of the interviewed farmers (between 57.5% and 90% acceptance per indicator). The feasibility of the individual indicators is overall assessed as positive. However, the study also shows a need for revision of the guide and makes suggestions for its improvement.The welfare of farm animals is being increasingly discussed in society and politics. To evaluate animal welfare, indicator systems are often used. Such a system has been developed by the German Association for Technology and Structures in Agriculture and suggested in the publication “Animal Welfare Indicators: Practical Guide—Pigs”. The association’s aim is to provide farmers with a useful method for recording the welfare of pigs. Crucial for the acceptance of the guide by farmers is a high degree of feasibility of the recommended indicators as well as the proposed methods for their recording. To evaluate this, 40 farmers keeping fattening pigs were interviewed. The guided semi-structured interview was conducted on the farms after the farmers evaluated the welfare of their fattening pigs according to the guide. The results are: Apart from the indicators faecal soiling and tail length, all the other eleven indicators are accepted for the assessment of fattening pig welfare by a majority of the interviewed farmers (between 57.5% and 90% acceptance per indicator). Furthermore, the feasibility of the individual indicators was assessed as being positive. The relationship between time expenditure and benefit was rated on a five-point scale at an average of 3.1 (medium), which clearly shows that there is a need for further development of this guide. Some possible changes with a potential for improvement could be identified; for example, the aggregation of the results after the collection of the individual indicators to an overall result that can be compared and interpreted.

A value chain analysis of interventions to control production diseases in the intensive pig production sector.

Value chain analysis (VCA) calculated the financial effects on food chain actors of interventions to improve animal health and welfare in the intensive pig sector. Two interventions to reduce production diseases were studied. A generic chain diagram of linkages between stakeholders and value-added dimensions was designed. Data on structure and financial performance were collected for the sector. The production parameters and financial effects of the interventions were then described to illustrate impact on the supply chain. The effects of the interventions were also assessed at market level using economic welfare analysis. The sectors in Finland and the UK are small in farm numbers and few companies produced much of the output in a largely vertically-integrated structure. The most beneficial intervention in financial terms to farmers was improved hygiene in pig fattening (around +50% in gross margin). It was calculated to reduce the consumer price for pig meat by up to 5% when applied at large, whereas for improved management measures, it would reduce consumer price by less than 0.5%. However, the latter added value also through food quality attributes. We show that good hygiene and animal care can add value. However, evaluation of the financial and social viability of the interventions is needed to decide what interventions are adopted. The structure of supply chains influences which policy measures could be applied. Of the two interventions, improved pig hygiene had the largest potential to improve efficiency and reduce costs. The studied interventions can also provide new business opportunities to farms, slaughterhouses and food sector companies. More evidence is needed to support public policies and business decision-making in the sector. For this, evidence on consumer attitudes to production diseases is needed. Nevertheless, the study makes an important contribution by showing how improvements in health and welfare benefit the whole chain.

Effects of Different Selenium Sources on Meat Quality and Shelf Life of Fattening Pigs.

Simple SummaryThis study was conducted to assess the effects of different Se sources on the growth performance, carcass performance, meat quality and shelf life of fattening pigs. A control diet was supplemented with SS, and experimental diets were supplemented SY, Se-Met, and SS + Se-Met, respectively. The data showed that using organic Se in fattening pig’s diet could improve meat quality and prolong the shelf life of pork. Thus, replacing inorganic Se in diet with organic Se improved meat quality and pork shelf life of fattening pigs significantly under the conditions of the current study.The aim of this study was to evaluate the effects of different Se sources on the meat quality and shelf life of fattening pigs. The control diet was supplemented with 0.3 mg/kg of Se from sodium selenite (SS), and experimental diets included 0.3, 0.3 and 0.15 + 0.15 mg/kg of Se from Se-enriched yeast (SY), selenomethionine (Se-Met) and SS + Se-Met, respectively. The results showed that using organic Se or Se + Se-Met in fattening pigs’ diet could increase average daily gain (ADG) (p < 0.05), decrease F/G (p < 0.05), reduce (p < 0.01) moisture, drip loss and cooking loss of longissimus thoracis, as well as increase (p < 0.05) protein and fat contents of longissimus thoracis. Diet supplementation with SY or Se + Se-Met could increase (p < 0.01) back fat thickness and skin thickness, and SY could increase (p < 0.01) belly fat rat. Adding SY or Se + Se-Met could reduce (p < 0.01) L value (45 min, 24 h). Adding Se-Met could decrease (p < 0.01) b value (45 min, 24 h), adding Se + Se-Met could reduce b value (45 min), and adding SY could reduce the b value (24 h). However, there were no (p < 0.05) significant effects on dressing percentage, carcass sloping length, eye muscle area, pH, a value (45 min) and a value (24 h) of longissimus thoracis. Moreover, the TVB-N contents of longissimus thoracis on the first and fifth days, the numbers of Lactobacillus on the third to seventh days and the numbers of E. coli in in the fifth to seventh days of longissimus thoracis were reduced (p < 0.01) by diet supplementation with organic Se. In conclusion, all the results indicate that replacing inorganic Se in diet with organic Se could improve meat quality of fattening pigs. In addition, organic Se could reduce the total volatile basic nitrogen (TVB-N) contents of longissimus thoracis and reduce the numbers of E. coli and Lactobacillus in longissimus thoracis, prolonging the shelf life of pork. These results demonstrated that organic Se supplementation was more effective than SS supplementation for meat quality and the shelf life of fattening pigs.

Validation of a New Resource-Efficient Feeding System for Fattening Pigs Using Increased Crude Fiber Concentrations in Diets: Feed Intake and Ammonia Emissions.

Simple SummaryThe feeding of fattening pigs and its associated ammonia emissions are current core problems in social debate that affects climate change and sustainability. Feeding methods offer great potential to increase animal welfare and sustainability, and negative impacts on the environment can be reduced. Fattening pigs differ in their performance potential and in their nutrient requirements. A high feed intake capacity can lead to luxury consumption. Diets rich in crude fiber should prevent excess feed intake and cause better nitrogen fixation by microorganisms in the animals’ large intestines. In a pig fattening farm, it was investigated whether and how diets rich in crude fiber can influence feed intake and ammonia emissions. The animals were divided into feeding groups according to their presumed performance potential by ultrasound examinations. Therein, body compositions were evaluated, and feed intake capacity and body weight were automatically recorded. The aim of the study was to enable adapted feeding of the animals by regarding their individual differences in body composition and performance potential. Roughage-based diets had significant influence on feed intake and did not increase ammonia emissions. Based on the results of this study a performance-based control of the feed intake should be made possible.The housing of fattening pigs, their feeding, and the emissions associated with this process are subjects of criticism. In order to reduce emissions and ensure resource efficiency, new paths must be taken; animals must be fed closer to their actual needs. In a pig fattening farm, 655 animals were grouped according their body weight and their body composition, consisting of weight and muscle-fat-ratio, which was determined by ultrasound examinations. The influence of different concentrations of triticale whole plant silage (WPS) (from 2.5% to 10%) on the feed intake capacity (3.88 kg to 2.71 kg (88% dry matter (DM))) of each group and the ability to control it was determined. Ammonia emissions were measured and the pens floor pollution was assessed. The animals could be distinguished significantly from each other by ultrasound examinations. The crude fiber influenced the level of daily feed intake. Ammonia emissions were not negatively influenced and could be partly reduced. There was no negative impact on surface contamination due to the increased use of crude fiber. The amount of daily feed intake was controlled by crude fiber rich diets. If these findings are adapted to certain types of pigs, a reduction of emissions and an increased resource efficiency can be expected.

Effect of blood serum enzymes on meat qualities of piglet productivity

The article presents the results of studies of fattening and meat qualities of young white pigs of different white breeds of different intensity of formation (Δt) in early ontogeny, biochemical parameters of blood serum (aspartate aminotransferase activity, alanine aminotransferase, alkaline transferase, alkaline phosphatase. It is established that according to the main indicators of fattening and meat qualities (age of reaching live weight of 100 kg, days; thickness of the sleeve at the level of 6-7 thoracic vertebrae, mm; length of chilled carcass, mm) young pigs of the controlled herd belong to the first class and class elite, and serum biochemical parameters are consistent with the physiological norm of clinically healthy animals. Taking into account the class of distribution by intensity of formation (Δt), a significant difference was established between animals of I (Δt = 0.795–0.832) and III (Δt = 0.660–0.703) groups on the average daily gain of live weight and age of reaching live weight of 100 kg. The relationship between the biochemical parameters of serum, fattening and meat characteristics of young pigs ranges from -0.250 to +0.385 and is unlikely. We offer in breeding and breeding work, along with the traditional methods of evaluation and selection of high-yielding animals use the method of evaluation and breeding indices.

Press review no 1-2020

Coronaviruses as well as influenza A viruses are widely spread in pig fattening and can cause high economical loss. Here we infected porcine precision-cut lung slices with porcine respiratory coronavirus and two Influenza A viruses to analyze if co-infection with these viruses may enhance disease outcome in swine. Ciliary activity of the epithelial cells in the bronchus of precision-cut lung slices was measured. Co-infection of PCLS reduced virulence of both virus species compared to mono-infection. Similar results were obtained by mono- and co-infection experiments on a porcine respiratory cell line. Again lower titers in co-infection groups indicated an interference of the two RNA viruses. This is in accordance with in vivo experiments, revealing cell innate immune answers to both PRCoV and SIV that are able to restrict the virulence and pathogenicity of the viruses.

Investigation of influence of growing pigs' positive affective state on behavioral and physiological parameters using structural equation modeling.

The aim of the present study was to investigate whether the primarily positive affective state of fattening pigs influences various behavioral and physiological parameters such as the pigs' playing behavior, way of behaving in behavioral tests, body language signals, or diameter, and astroglia cell numbers of hippocampi, salivary immunoglobulin A (IgA) content, or salivary protein composition. Additionally, the suitability of the variables mentioned was examined to assess the pigs' positive affective state in practice, which still constitutes a latent variable not itself measurable. For this, a dataset including behavioral and physiological data of 60 fattening pigs from 3 different farms with different housing systems was analyzed by the partial least squares structural equation modeling (PLS-SEM) method. A hierarchical component model (HCM) was used including the pigs' positive affective state as a higher-order component (HOC) and the behavioral and physiological parameters as lower-order components (LOC). Playing behavior, body language signals, and behavioral tests were revealed, in this order, to be most influenced by the pigs' positive affective state since these resulted in the corresponding path coefficients (PC) of PC = 0.83, PC = 0.79, and PC = 0.62, respectively. Additionally moderate and weak R2-values occurred for the endogenous latent variables playing behavior (R2 = 69.8%), body language signals (R2 = 62.7%), and behavioral tests (R2 = 39.5%). Furthermore, the indicator of the "locomotor play" showed the highest indicator reliability (IR) (IR = 0.85) to estimate the latent variable of pigs' positive affective state. The results of the present study supplement the comprehension and assessment of the pigs' positive affective state in general.

Efficiency of pig fattening

Efficiency of pig fattening

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.

Risk factors for the infection with Brachyspira hyodysenteriae in pig herds

Swine dysentery (SD), caused by infection with Brachyspira hyodysenteriae, is a serious disease in pig production worldwide. Quantitative risk factors triggering the occurrence of infection are unknown. The present case-control study aimed at identifying major risk factors related to presence of B. hyodysenteriae in pig herds. Twenty case herds and 60 randomly selected control herds with a minimum herd size of ‘10 sows/ 80 fattening pigs’ were examined by means of a questionnaire-based interview and a herd examination. Herds with previous eradication of SD were excluded. Logistic regression models revealed that the ‘positive/suspicious SD status of source herds’, the regular application of treatment, purchasing more than 4 batches/ year, contact to foxes, diagnostics performed during last 12 months, liquid feeding systems, rats on farm, and >250 fatting places were associated with higher chances of a herd to be infected. On the contrary, having different sources of grower pigs within one batch, the presence of raptor birds and the presence of martens in the region were associated with fewer chances of being infected. The final multivariable logistic regression model identified purchasing more than 4 batches/ year (OR = 7.5, 95 % CI 1.8–54.3) and contact to foxes (OR = 5.9; 97.5 % CI 1.2–34.6) as the two main risk factors in our study. ‘More than 4 batches/ year’ implies continuous herd management supporting persistence of B. hyodysenteriae in an infected herd, but also increased number of purchases each increasing the risk of B. hyodysenteriae introduction by carrier pigs or transport vehicles. Foxes might be infected with B. hyodysenteriae by feeding on positive piglets and rodents. Besides, ‘contact to foxes’ might represent a lack in biosecurity. In conclusion, the risk factors detected underline the importance of biosecurity in SD prevention and control.

Comparative 1-year performance study of two full-scale biotrickling filters for ammonia removal including nitrous oxide emission monitoring

This study presents the start-up and 1-year performance study of two full-scale biotrickling filters or biological air scrubbers at a pig fattening facility in terms of ammonia removal and nitrous oxide production. Two newly-built multi-stage biotrickling filters were continuously monitored for these gases and for washing water characteristics. Although pH and electrical conductivity in the washing water are used in practice as a cheap and easy way to monitor the ammonia removal efficiency of biotrickling filters at pig housing facilities, it was shown that the relation between these variables is not always straightforward. Setting up a nitrogen balance over both biotrickling filters suggested denitrification activity. Additionally, the effect of inoculation with activated sludge of a wastewater treatment plant was investigated by inoculation of one of the two biotrickling filters. The inoculated biotrickling filter showed a fast start-up of nitrification and hardly any nitrite accumulation in the washing water. The ammonia removal efficiency was higher and the nitrous oxide production was slightly lower in the inoculated biotrickling filter compared to the non-inoculated.

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.

Evaluation of a Cost-Effective Ammonia Monitoring System for Continuous Real-Time Concentration Measurements in a Fattening Pig Barn.

Ammonia (NH3) emission is one of the major environmental issues in livestock farming. Gas measurements are required to study the emission process, to establish emission factors, and to assess the efficiency of emission reduction techniques. However, the current methods for acquiring reference measurements of NH3 are either high in cost or labor intensive. In this study, a cost-effective ammonia monitoring system (AMS) was constructed from a commercially-available gas analyzing module based on tunable diode laser absorption (TDLA) spectroscopy. To cope with the negative measurement biases caused by differing inlet pressures, a set of correction equations was formulated. Field validation of the AMS on NH3 measurement was conducted in a fattening pig barn, where the system was compared to a Fourier-transform infrared (FTIR) spectroscopy analyzer. Under two test conditions in a fattening pig barn, the absolute error of the AMS measurements with respect to the average obtained values between the AMS and the FTIR was respectively 0.66 and 0.08 ppmv, corresponding to 5.9% and 0.5% relative error. Potential sources of the measurement uncertainties in both the AMS and FTIR were discussed. The test results demonstrated that the AMS was capable of performing high-quality measurement with sub-ppm accuracy, making it a promising cost-effective tool for establishing NH3 emission factors and studying NH3 emission processes in pig houses.

Prevalence and Dynamics of Pathogenic Yersinia enterocolitica 4/O:3 Among Finnish Piglets, Fattening Pigs, and Sows.

Pigs are considered the main reservoir of Yersinia enterocolitica, and hence, understanding the ecology of this foodborne pathogen at the farm level is crucial. We calculated Bayesian estimates for the ability of a commercial enzyme-linked immunosorbent assay (ELISA) diagnostic test kit to detect antibodies against pathogenic Yersinia in pigs. The sensitivity and specificity of the test were 75.4% and 98.1%, respectively. We also studied the dynamics of Y. enterocolitica infection in 3 farrow-to-finish pig farms by following the same 30 pens of pigs through their lifetime from farrowing unit to slaughterhouse. Each farm was sampled 4 times, and 864 fecal and 730 serum samples were collected altogether. Pathogenic Y. enterocolitica 4/O:3 was isolated from 31.6% of the fecal samples by culturing, and Yersinia antibodies were detected in 38.2% of the serum samples with the commercial ELISA test. The pathogen was not isolated from farrowing units or all-in/all-out weaning units. However, in the weaning and fattening units using continuous management systems, the pathogen was isolated from every pen at some point of the study. After the pigs were transported into slaughterhouse, 150 tonsils were collected and 96.7% were positive by culturing. Among the strains isolated from feces and tonsils, 56 different genotypes of pathogenic Y. enterocolitica 4/O:3 were found by multilocus variable-number tandem-repeat analysis (MLVA). Finally, we collected tonsils of 266 sows from 115 farrowing farms, and Y. enterocolitica 4/O:3 was detected in 6.0% of the samples by the culture method, whereas 77.1% of the tonsils were serologically positive; the estimate for true seroprevalence was 95.8%. In conclusion, sows may not be the main source of Y. enterocolitica for piglets, although sows may still play a role in maintaining Y. enterocolitica in pig farms. Instead, pigs appear to get this foodborne pathogen mainly during the fattening period, especially if continuous management is applied.

Effect of housing system on fattening and slaughter results and profitability of pig fattening

Effect of housing system on fattening and slaughter results and profitability of pig fattening

Ammonia volatilization from different pig slurries applied on wheat stubble using different land spreading techniques under French conditions

Field experiments were conducted in Brittany (western France) in 2012 to measure and compare ammonia emissions after surface application and injection of fattening and farrowing-gestating pig slurry. Experiments were conducted on wheat stubble. Ammonia emissions were measured using wind tunnels. The results showed a reduction in ammonia emissions after injection compared to broadcast spreading whatever the slurry. However, the reduction in ammonia volatilization using the injection technique was less with the farrowing/gestating slurry (65% reduction) than with the fattening slurry (97% reduction). The lesser reduction was associated with lower emissions of total ammonia nitrogen in farrowing slurry (16% of the N-NH4+ applied) compared to the fattening slurry (74% of the N-NH4+ applied). The lower ammonia emissions were attributed to lower dry matter content and less ammonium in the farrowing/gestating pig slurry compared to the fattening pig slurry.