Pig House Research Articles

Supplementation of Non-Starch Polysaccharide Enzymes Cocktail in a Corn-Miscellaneous Meal Diet Improves Nutrient Digestibility and Reduces Carbon Dioxide Emissions in Finishing Pigs.

Simple SummaryThe objective of the present study was to investigate the effect of the non-starch polysaccharide enzymes cocktail (NSPEC) on growth performance, nutrient digestion and gas emissions on finishing pigs. The addition of the NSPEC into a corn-miscellaneous meal diet improved feed conversion ratio and increased the apparent total tract digestibility of dry matter, neutral detergent fiber, acid detergent fiber, crude protein and gross energy of the finishing pigs. Furthermore, the digestible energy of the diet was also increased by the NSPEC supplementation in the diet. In addition, the inclusion of NSPEC in the corn-miscellaneous meal diet reduced carbon dioxide emissions of a finishing pig house. The accumulation of manure could increase the release of ammonia in a pig house.This study was carried out to evaluate the effect of the addition of the non-starch polysaccharide enzymes cocktail (NSPEC) on growth performance, nutrient digestibility and gas emissions in a corn-miscellaneous meal-based diet for finishing pigs. The NSPEC is a combination of cellulase, xylanase, β-glucanase, β-mannanase, α-galactosidase and pectinase optimized by assessing the in vitro dry matter digestibility (IVDMD) of corn-miscellaneous meal diet using an in vitro method of simulating digestion in the stomach and intestine of growing pigs. Growth performance and apparent total tract digestibility (ATTD) of nutrients and energy were measured. The gas concentration of ammonia, carbon dioxide, nitrous oxide and methane in the environmental assessment chambers were determined. The gas detecting period was divided into three frequencies of manure removal of every 1d, 2d and 3d. The addition of NSPEC into the corn-miscellaneous meal diet decreased feed conversation rate (FCR) and increased the ATTD of dry matter, crude protein, gross energy, neutral detergent fiber and acid detergent fiber of pigs (p < 0.05). The digestible energy was also improved (p < 0.05) significantly by NSPEC supplementation in the diet. Furthermore, the supplementation of the NSPEC reduced (p < 0.05) carbon dioxide concentration in the chambers. The ammonia emissions were significantly increased according to average 1d, 2d and 3d manure removal procedures (p < 0.01). These results indicated that the inclusion of optimal NSPEC in a corn-miscellaneous meal diet improved growth performance, nutrient digestibility and reduced carbon dioxide emissions on finishing pigs. The accumulated manure could increase the release of ammonia in a pig house.

Enrichment use in finishing pigs and its relationship with damaging behaviours: Comparing three wood species and a rubber floor toy

Environmental enrichment in pig housing is a legal requirement under current EU legislation, but some recommended loose materials may cause obstructions in fully-slatted systems. Wood is an organic material that could be compatible with slatted systems. This study investigated enrichment use in finishing pigs (three wood species and a rubber floor toy) and explored the relationship between use and damaging behaviours, and physiological and physical measures of stress and injury. Individual variation in enrichment use within pen was also investigated. Pigs (12 weeks old; week 0) were housed in 40 pens of seven pigs (n = 280). One of four different enrichment items (one spruce, larch, or beech wooden post, or rubber floor toy) was randomly assigned to each pen (10 pens/treatment). The behaviour of each individually marked pig was observed continuously from video recordings taken on six different occasions (twice during week 2, 4 and 7; 1 h per occasion). Individual tail/ear lesion and tear staining scores were recorded every 2 weeks. Saliva samples for cortisol analysis were obtained from three focal pigs per pen every 2 weeks. These focal pigs were selected based on the latency to approach the experimenter on the first sampling day and classified as ‘Approach’, ‘Neutral’ or ‘Avoid’. Carcasses were inspected for tail lesions and potential oral damage. Time spent using enrichment was higher in pigs with spruce and rubber toy than with larch and beech (P < 0.001). Spruce was used up the most quickly and was the softest of the wood species (P < 0.001). High use of spruce was not due to consistent high use by certain pigs. No treatment effect on any other behaviour was recorded, but enrichment use was positively correlated with damaging behaviours at pen level (P < 0.001). Spruce pigs had slightly more severe tail lesion scores than Beech (P < 0.05). Salivary cortisol did not differ between treatments but was higher in ‘Avoid’ than ‘Approach’ pigs (P = 0.04). No clear oral damage that could be attributed to using wood was found. By investigating enrichment use at both pen and individual level, a more complete picture was obtained of how pigs used the enrichment. Wood appears to be a safe material to use as environmental enrichment for pigs and a softer wood species was preferred by pigs with equal preference for the rubber floor toy.

Model-based evaluation of ammonia removal in biological air scrubbers

A mechanistic model for ammonia removal in a countercurrent biological air scrubber was set up. This model was used to study the effect of the influent characteristics – air temperature, ventilation rate and ammonia load, on ammonia removal efficiency. Besides mass balances of the components participating in the biological conversions, the water mass balance and the heat balance were considered. The effects of the pH and the concentration of the nitrogen components on the driving force for mass transfer were examined. The model output was compared against experimental data from a pig housing facility. Simulations were performed to assess the usefulness of pH control and to investigate the effect of inflow air conditions on the ammonia removal efficiency. The study found out that although pH control affected the nitrogen component distribution in the washing water, it hardly affected the ammonia removal efficiency. Thus, pH control for biological air scrubbers is not recommended in practice, however, an on/off pH control system adding only acid at critical moments (pH above 7.5) could be considered. The variations in the ammonia removal efficiency are mainly caused by a changing ventilation rate rather than air temperature fluctuations or ammonia load.

Prioritization of Farm Animal Welfare Issues Using Expert Consensus

Prioritization of animal welfare issues can help identify which areas most require research funding and raise awareness of best practices. A modified Delphi method was used to obtain expert opinion on the highest priority welfare issues for UK farmed livestock. Fifty-eight UK-based experts were recruited onto the study, with a minimum of 3 years experience of working with either cattle, pigs, poultry, or small ruminants (12–16 experts per group). Experts were chosen to represent a broad range of opinions. Two rounds of surveys were conducted online using Online Survey, and the final round was an in-person workshop with 21 experts. In the first survey, experts were provided with a comprehensive list of species-specific welfare issues derived from the literature. Participants were asked to score each welfare issue, for (i) severity, (ii) duration, and (iii) prevalence on a 6-point Likert scale. The results of the first survey were reviewed and the welfare issues which scored a neutral-to-high response (scores 3–6) were carried forward. In round 2, participants were asked whether they agreed or disagreed with the rankings that were made from the results of round 1. The final stage of the process was a workshop, which consisted of a combination of group exercises and discussions, to reach the final consensus. Welfare priority lists were divided into two categories: severity/duration, and prevalence, to identify the priority welfare issues affecting individual animals and the population, respectively. Across all farmed species common concerns were inadequate or inappropriate nutrition, inability of stockpeople to recognize or treat welfare issues (such as pain or behavioral problems), lameness, chronic or endemic health issues, euthanasia and mortality and morbidity of neonates. Specific concerns related to behavioral restriction and damaging or abnormal behavior in pigs, poultry and dairy animals, inadequate housing for pigs and poultry, consequences of breeding decisions in pigs and poultry, and lack of access to veterinary care in sheep and beef. This Delphi process resulted in consensus on the most significant welfare challenges faced by UK livestock species and can help to guide future research and education priority decisions.

Environmental impacts of housing conditions and manure management in European pig production systems through a life cycle perspective: A case study in Denmark

The potential of modifications in the housing conditions and manure management to reduce the environmental impact of a European pig production system were evaluated. The study was carried out using a cradle-to-farm gate life cycle assessment (LCA), with a functional unit of 1 kg of live weight pig at farm gate. The study used Danish pig systems as a case in point, with data provided by the Danish Pig Research Centre (SEGES).Potential environmental impact hotspots at pig housing and manure management were identified through a local sensitivity analysis. A set of pig housing and manure management alternative scenarios were analysed using parallel Monte Carlo simulations, to quantify interactions between these two components of the system. The manure management scenarios were slurry acidification, screw-press slurry separation and centralised anaerobic digestion of slurry. The pig housing scenarios were constructed around variations of the following factors: i) level of barn insulation, ii) in-barn temperature, iii) ventilation efficiency, iv) level of slurry dilution and v) frequency of slurry removal from barn pits.Anaerobic digestion significantly reduced the environmental impact for Non-Renewable Resource Use (−34.1% compared to baseline), Non-Renewable Energy Use (−40.1%) and Global Warming Potential (−9.20%). Slurry acidification led to significant reductions in Acidification (−28.1%) and Eutrophication Potential (−14.2%). Slurry separation significantly reduced only Non-Renewable Energy Use (−2.26%).The scenario analysis showed that the environmental performance of all manure management alternatives was affected by variations in all housing related factors, except for in-barn temperature. The largest improvement in environmental performance of the manure management component was achieved for Acidification Potential (−5.51%) by increasing the level of slurry dilution under baseline manure management conditions. Slurry acidification was the least sensitive manure management alternative to modifications in pig housing. Both manure management and housing conditions have the potential to reduce the environmental impact of pig systems in Europe.

Development of Wearable Device for Monitoring Working Environment in Pig House

Development of Wearable Device for Monitoring Working Environment in Pig House

Impact of Slatted Floor Configuration on Manure Drainage and Growth Performance of Finishing Pigs

HighlightsUnder the same conditions of cast-iron usage, increasing the width of the gap and slat width within a certain range can enhance the bearing capacity of the slatted floors.Variations in the gap and slat width do not significantly affect pig growth performance.The recommended gap width of a cast-iron slatted floor in a fattening pig house is 15 mm.Abstract.Slatted flooring is an important part of the structure of pig houses and can aid in the removal of pig manure to underground ditches via gravity and locomotion. In this study, four different cast-iron slatted floor configurations with different gap widths (10, 15, and 20 mm) and slat widths (10 and 15 mm) were set up in 11 partially slatted-floor pig pens of the same size, each housing 10 fattening pigs with body weights of approximately 63 kg. The residual manure on the solid concrete floor area and a cast-iron slatted floor area were collected at different time intervals (24, 48, and 72 h) and weighed. According to previous studies on total manure and total urine production of pigs, the manure drainage capacity of four types of slatted floor was calculated. The growth performance of all of the pigs was monitored throughout the experiment. The ultimate bearing capacity of the four types of slatted floors was measured by a third-party professional testing organization. The results showed that the gap width and slat width of the cast-iron slatted floor had significant effects on its ultimate bearing capacity and manure drainage capacity (P&amp;lt;0.05) but had no significant effect on pig growth performance (P&amp;gt;0.05). The recommended gap width of a cast-iron slatted floor in a fattening pigs house is 15 mm. These findings can be used to optimize the design of cast-iron slatted flooring for fattening pigs, which must also be safe, economical, and efficient. Keywords: Cast iron, Dimensions, Fattening pig, Manure drainage, Slatted floor.

Optimum insulation thickness for the sandwich structure livestock buildings external envelopes in different climate regions of China

Determining the optimum insulation thicknesses of external envelopes for livestock buildings are one of the most effective metrics to decrease energy requirements. This study was carried out to determine the optimum insulation thicknesses for livestock buildings in different climate zones, to examine the effects of insulation thickness and material (foam glass, mineral wool, expanded polystyrene, foamed polyurethane, foamed polyvinyl chloride, and expanded polyethylene) on life cycle total cost, life cycle savings, and payback period. The finishing pig houses and laying hen buildings with sandwich wall structures (color steel laminboard) in five typical cities were studied using the degree-days method with economic models. Optimal insulation thicknesses ranged from 0.05 m to 0.25 m and 0.02 m to 0.24 m in finishing pig houses and poultry buildings, respectively; the life cycle total costs ranged from 16.49 to 37.98 $/m2 and 13.37 to 36.84 $/m2; the life cycle savings ranged from 29.13 to 220.60 $/m2 and 0 to 202.13 $/m2; and the payback period ranged from 1.11 to 5.81 years and 1.19 to 20.76 years, respectively. Foamed polyurethane provided the highest life cycle savings, while foam glass had the lowest. In this research, the insulation thicknesses for the sandwich structure livestock buildings external envelopes are optimized, and the energy saving can be obtained by using proper insulation thickness in different regions. Furthermore, it can increase the knowledge about energy consumption in the livestock buildings and the results can be also a useful tool for farmers. Keywords: livestock building, insulation material, optimum insulation thicknesses, degree-days, life cycle total cost, life cycle saving, payback period DOI: 10.25165/j.ijabe.20201301.5280 Citation: Wang Y, Li B M, Zheng W C. Optimum insulation thickness for the sandwich structure livestock buildings external envelopes in different climate regions of China. Int J Agric & Biol Eng, 2020; 13(1): 29–41.

Field Test and Economic Analysis of Energy-Saving Renovation for an Old Nursery Pig Building in Beijing, China

HighlightsAn old nursery pig building was retrofitted to potentially improve envelope insulation capacity.A mathematical theory based on coal consumption was established to evaluate energy efficiency of insulation renovation for a nursery pig building.The heat loss of the nursery pig house with 90-mm-thick extruded polystyrene boards was 60% lower than that without the materials.Ground source heat pump and air source heat pump are economical and environmental-friendly heating systems.Abstract. Appropriate renovation of old buildings is critical for energy-efficient pig production. Currently, energy consumption, especially coal consumption, keeps on rising in the production. Therefore, it is essential to develop energy-saving renovation methods for old nursery pig buildings and use cleaner heating energies. A mathematical theory based on coal consumption was established to evaluate energy efficiency of insulation renovation. Two nursery pig houses were tested in this experiment. One was the retrofitted house with the 90-mm-thick extruded polystyrene boards embedded onto outer walls, and the other one was served as a control house without those insulation materials. The results show that the air temperature and inside surface temperature of the retrofitted house were significantly higher than those of the control house in winter. Therefore, though adding insulation layers to walls, the envelope insulation capacity was improved. Meanwhile, the heat loss of the retrofitted house was 60% lower than that of the control house (11.08 W m-2 vs. 27.93 W m-2), when the theoretical ventilation rate was 1560 m3 h-1. In addition, with the prohibition of the coal usage in forseeable future of China, the ground source heat pump and air source heat pump can be economical solutions for heating systems with clean and renewable energy. Keywords: Air source heat pump, Extruded polystyrene board, Ground source heat pump, Heating, Thermal insulation.

다종물질이송 전산해석기법을 이용한 양돈사 환기 분석

한국의 경제 발전에 따라 양돈 사업의 규모가 커지고 대단지화 되면서, 생산성 향상과 높은 품질을 충족시키기 위해 축사시설의 체계적인 관리가 요구되고 있다. 그러나 효율성을 위해 밀집된 구조에서는 종종 여름철에 공기의 질이 나빠지고 온도가 높아지는 등의 문제를 일으킬 수 있다. 돼지는 저산소 및 고온에 매우 취약하기 때문에 생산성을 높이기 위한 환기 유지는 매우 중요하다. 이에 본 연구에서는 전산유체역학(CFD, computational fluid dynamics)을 이용하여 환기 시스템의 문제점 및 개선 사항을 분석하는 방법을 제안하였다. 유한체적법(FVM, finite volume method) 기반의 fluent 프로그램이 사용되었고 난류 모델로 RNG standard k-ε 모델을 사용하였다. 환기 시스템의 효율적인 설계를 위해 실제 단층의 단순 구조 양돈사와 다층의 대형 양돈사를 대상으로 다종물질이송(multispecies transport) 해석기법을 이용하여 환기 효율 및 성능을 분석하였으며, 개선된 시스템의 유동순환이 원활하게 이루어짐을 확인하였다.

The investigation of combined ventilation-biofilter systems using recycled treated wastewater on odor reduction efficiency.

ObjectiveThe present study aimed to evaluate the performance of odor abatement by using two different ventilation-biofilter systems with recycled stablized swine wastewater.MethodsThe performance of odor removal efficiency was evaluated using two different ventilation-biofilter-recycled wastewater arrangements. A recirculating air-flow ventilation system connected to a vertical biofilter (M1) and a plug-flow ventilation system connected to a horizontal biofilter (M2) were installed. Water dripping over the surface of the biofilter was recycled at a flow rate of 0.83 L/h in summer and 0.58 L/h in winter to reduce odorous compounds and particulate matter (PM). The experiments were performed for 64 days with M1 and M2 to investigate how these two ventilation-biofilter systems influenced the reduction of odor compounds in the model houses. Odorous compounds, NH3 and volatile organic compounds (VOCs) were analyzed, and microclimatic variables such as temperature, humidity, and PM were monitored.ResultsAmmonia concentration inside M1 was about 41% higher on average than that in M2. PM and total suspended particles (TSPs) inside M1 were about 62.2% and 69.9%, respectively, higher than those in M2. TSPs in the model house were positively correlated with the concentration of NH3 and VOCs.ConclusionM2 emitted lower concentration of odorous compounds than M1. Moreover, M2 could maintain the optimum temperature condition for a swine house during the cooler season. The plug-flow ventilation–horizontal biofilter system could be used for pig houses to minimize air pollution produced by swine farming activities and maintain optimum microclimate conditions for pigs.

Effects of Odorous Components Derived from Pig’s Feces on Pig House Odor

Effects of Odorous Components Derived from Pig’s Feces on Pig House Odor

Silver nanoparticles as potential antiviral agents against African swine fever virus

African swine fever virus (ASFV) is the cause of a highly contagious and fatal disease in domestic swine, but no vaccine or effective medicine is available so far, therefore, looking for a novel and effective anti-ASFV agent is a very imperative mission. Silver nanoparticles (SNPs) have been recently emerged as novel antiviral agents against numerous viruses, but, their antiviral activity against ASFV has not been investigated. In this study, the antiviral ability of SNPs against ASFV was reported. The microbial contamination in the pig house was significantly reduced by spraying the SNP solution 25 ppm. SNP solution with the concentration of 0.78 ppm does not show any toxicity to porcine alveolar macrophage cells; while completely inhibits ASFV at the titer of 103 HAD50. This study confirms that SNPs have a highly antiviral ability against ASFV and is a promising disinfectant that can be used to prevent the ASFV transmission.

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.

Seasonal variations of microbial assemblage in fine particulate matter from a nursery pig house

The microorganisms contained in PM2.5 from livestock houses can spread over long distances through airborne transmission. As such, the potential bacterial pathogens and fungal allergens within can pose a formidable threat to nearby residents’ health and the overall environment. However, little is known about the microbial assemblage contained in PM2.5 from pig houses. In this study, 16S and 18S rRNA gene sequencing was employed to analyze the bacterial and fungal assemblage contained in PM2.5 from a nursery pig house across four seasons, respectively. The results showed that alpha diversity was higher in summer and autumn compared to the spring and winter. The bacterial and fungal assemblage varied according to season. At the phylum level, the dominant bacteria and fungi were Firmicutes and Basidiomycota, respectively, across the four seasons. At the genus level, a total of five potential bacterial pathogen and 20 potential fungal allergen genera were identified across the samples. The most abundant bacterial pathogen and fungal allergen genera were observed in summer and autumn, respectively, but neither had a significant correlation with PM2.5 concentration. Moreover, microbial diversity and the relative abundance of fungal allergen genera were positively correlated with temperature and relative humidity. It can be concluded that microbial diversity and assemblage varied significantly among the seasons in a nursery pig house, and this can be useful in exploring the potential risks of PM2.5 from pig houses across all four seasons.

Floor space requirement for housing and welfare of pigs under Indian perspective

Pork production in India has almost doubled from 0.204 MT to 0.402 MT in last decade (2007–08 to 2017–18). Best utilization of pen space without adversely affecting the productivity and well-being of pigs is crucial for pork sector. Most of the developed countries recommend floor space requirement of 0.15 m2/pig for weaners and South Asian countries as 0.3 to 0.5 m2/pig without any provision of open space. In India, very few studies have been carried out on space allowance in pigs. Since, Indian Standards (IS: 3916–1966) for pig housing are very old (1960s), study on the floor space requirement for individual pig in all the stages and different group sizes is very much essential for practical pig rearing. The negative impact of crowding on feed intake and growth is well documented. Higher stocking density may also adversely affect feed conversion efficiency. However, reduction in floor area (33% and 50%) in comparison to IS did not affect major performance traits. Space allowance is one of the important factors in the establishment of social rank. In European countries, the most economical allocation of pen floor space was less than the space needed for optimal performance. Reduced space allowances may lead to amplified aggression-related skin lesion scores. Thus, in space restricted environments, the dominance hierarchy becomes less stable amongst pigs and tail and ear biting are also commonly observed. Based on studies done so far it is concluded that there is scope of reduction in floor space allowance in comparison to IS specifications without compromising welfare status of pigs and further research in this area need to be encouraged.

Rearing Pigs with Intact Tails-Experiences and Practical Solutions in Sweden.

Tail biting is a common issue within commercial pig production. It is mainly an indicator of inadequate housing environment and results in reduced health welfare and production. To reduce the impact of tail biting, pigs are commonly tail docked, without pain relief, within the first week of life. EU Council Directive 2008/120/EC prohibits routine tail docking, but the practice is still widely used in many Member States. Sweden has banned tail docking since 1988 and all pigs have intact tails, yet tail biting is a minor problem. This paper summarises and synthesises experimental findings and practical expertise in production of undocked pigs in Sweden and describes solutions to facilitate a transition to producing pigs with intact tails within intensive pig production in the EU. Swedish pig housing conditions and management differ in many aspects from those in other EU Member States. Swedish experiences show that lower stocking density, provision of sufficient feeding space, no fully slatted flooring, strict maximum levels for noxious gases and regular provision of litter material are crucial for success when rearing pigs with intact tails. To prevent tail biting and to eliminate the need for tail docking, we strongly recommend that EU legislation should more clearly match the biological needs of pigs, as is done in Swedish legislation.

Prevalence, Antibiogram, and Resistance Profile of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates from Pig Farms in Luzon, Philippines.

This cross-sectional study was conducted to determine the prevalence, antibiogram, and resistance profile of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) isolates from healthy pigs and pig farms in Luzon, Philippines. A total of 162 rectal samples from healthy finisher and breeder pigs and boot swab samples from pig houses were collected from 54 randomly selected pig farms. Bacteria were isolated and screened using MacConkey agar plate supplemented with 1 mg/L cefotaxime. Identification of bacteria and antimicrobial susceptibility test were carried out through Vitek® 2 and combined disk test. PCR amplifications were carried out in all isolates targeting blaCTX-M and its five major groupings, blaTEM, and blaSHV. The farm prevalence of ESBL-EC was 57.41% (95% confidence interval [CI] = 43.21-70.77). A total of 48 (29.63%) ESBL-EC isolates were isolated from samples that showed 14 different phenotypic multidrug resistance patterns. The prevalence of blaCTX-M gene was 91.67% (95% CI = 80.02-97.68). All major blaCTX-M-groups except blaCTX-M-25group were detected. The blaCTX-M-1 was the most prevalent blaCTX-M gene, 75.0% (95% CI = 60.40-86.36). The prevalence of blaTEM and blaSHV genes was 91.67% (95% CI = 80.02-97.68) and 60.42% (95% CI = 45.27-74.23), respectively. Coexistence of different blaCTX-M, blaTEM, and blaSHV genes was observed in 44 isolates with 20 different genotypic patterns. High prevalence, diverse antibiogram profile, and genotypic resistance pattern of ESBL-EC isolates from healthy pigs and pig farms were observed in this study that could result in possible transmission to farm workers, susceptible bacteria, and the environment.

Costs and Benefits of Alternative Strategies to Control the Spread of Livestock-Acquired Methicillin-Resistant Staphylococcus Aureus From Pig Production

BackgroundLivestock-acquired methicillin-resistant Staphylococcus aureus (LA-MRSA) is a concern in healthcare and a political priority in some countries. ObjectiveThis study investigates the net societal costs of 2 alternative strategies for controlling LA-MRSA in Denmark: (1) eradicating LA-MRSA in all pig housing units, and (2) containing LA-MRSA within the units. MethodsBenefits and costs are considered for affected economic sectors: healthcare, pig production, pig-related industries, and public administration. ResultsThe cost to society of eradication is estimated at €2.3 to €2.5 billion (present value). Containment will cost €55 to €93 million. For both strategies, the main cost lies in primary pig production—for containment this is mainly due to establishing and operating anterooms and shower rooms, and for eradication it is due to production losses, loss of genetic resources, and costs of cleaning and disinfection. ConclusionCompared with these costs, health economic benefits are moderate for both strategies. Containment is superior to eradication when measured by a benefit-cost ratio.

Multi-phase flow assessment for the fermentation process in mono-substrate reactor with skeleton bed

Abstract The selected techniques were reviewed and their technological aspects were characterized in the context of multi-phase flow for biogas production. The conditions of anaerobic fermentation for pig slurry in a mono-substrate reactor with skeleton bed were analysed. The required technical and technological criteria for producing raw biogas were indicated. Design and construction of the mono-substrate model, biogas flow reactor, developed for cooperation with livestock buildings of various sizes and power from 2.5 kW to 40 kW. The installation has the form of a sealed fermentation tank filled with a skeletal deposit constituting a peculiar spatial system with regular shapes and a rough surface. Incorporating a plant in such a production cycle that enables the entire slurry stream to be directed from the cowshed or pig house underrun channels to the reactor operating in the flow mode, where anaerobic digestion will take place, allows to obtain a biogas. The paper presents preliminary results of experimental investigations in the field of hydrodynamic substrate mixing system for biogas flow assessment by the adhesive bed in the context of biogas production. The aim of the study was to assessment and shows the influence of the Reynolds number on the biogas resistance factor for the fermentation process in mono-substrate reactor with adhesive deposit. The measurement results indicate a clear effect of the Reynolds number in relation to the descending flow resistance coefficient for the adhesive bed.