Pig Production Systems Research Articles

Prevalence and antimicrobial resistance of MRSA across different pig age groups in an intensive pig production system in Australia.

This observational study aimed to determine MRSA prevalence using strain-specific real-time PCR at the pig level, stratified by age groupings, within a pig enterprise. A total of 658 samples were collected from individual pigs (n=618) and the piggery environment (n=40), distributed amongst five different pig age groups. Presumptive MRSA isolates were confirmed by the presence of mecA, and MALDI-TOF was performed for species verification. All isolates were tested against 18 different antimicrobials. MRSA was isolated from 75.2% (95% CI 71.8-78.6) of samples collected from pigs, and 71% of the MRSA isolates from this source were identified as community-associated (CA)-MRSA ST93, while the remainder were livestock-associated (LA)-MRSA ST398. Amongst environmental isolates, 80% (CI 64.3-95.7) were ST93 and the remainder ST398. All MRSA isolates from pigs and the environment were susceptible to ciprofloxacin, gentamicin, linezolid, mupirocin, rifampicin, sulfamethoxazole-trimethoprim, teicoplanin and vancomycin. Phenotypic rates of resistance were penicillin (100%), clindamycin (97.6%), erythromycin (96.3%), ceftiofur (93.7%), chloramphenicol (81.2%), tetracycline (63.1%) and amoxicillin-clavulanate (63.9%). A low prevalence of resistance (9.2%) was observed against neomycin and quinupristin-dalfopristin. The probability of MRSA carriage in dry sows (42.2%) was found to be significantly lower (p<.001) when compared to other age groups: farrowing sows (76.8%, RR1.82), weaners (97.8%, RR 2.32), growers (94.2%, RR 2.23) and finishers (98.3%, RR 2.33). Amongst different production age groups, a significant difference was also found in antimicrobial resistance for amoxicillin-clavulanate, neomycin, chloramphenicol and tetracycline. Using the RT-PCR assay adopted in this study, filtering of highly prevalent ST93 and non-ST93 isolates was performed at high throughput and low cost. In conclusion, this study found that weaner pigs presented a higher risk for CA-MRSA and antimicrobial resistance compared to other age groups. These findings have major implications for how investigations of MRSA outbreaks should be approached under the One-Health context.

Vaccination Is a Suitable Tool in the Control of Aujeszky's Disease Outbreaks in Pigs Using a Population Dynamics P Systems Model.

Simple SummaryMaximizing the efficiency of pork production in line with sustainability and environmental restrictions presents a challenge for the pig industry in the coming years. It is necessary to develop practices based on cost/benefit analyses of the effects of disease on animal performance. Diseases can be controlled in various ways, such as vaccination programs and management protocols, among others, to control pathogens. We have developed a model to disentangle the effects of management and vaccination strategies to control one of the most important pig viral diseases, Aujeszky disease. Our results suggest that after confirming the diagnosis, early vaccination of most of the population is critical to decrease the spread of the virus and minimize its impact on pig productivity. However, the effect of management is negligible for the control of this virus. Thus, this model can be used to evaluate preventive medicine programs in the control of known diseases and for new ones that could appear in the future.Aujeszky’s disease is one of the main pig viral diseases and results in considerable economic losses in the pork production industry. The disease can be controlled using preventive measures such as improved stock management and vaccination throughout the pig-rearing period. We developed a stochastic model based on Population Dynamics P systems (PDP) models for a standard pig production system to differentiate between the effects of pig farm management regimes and vaccination strategies on the control of Aujeszky’s disease under several different epidemiological scenarios. Our results suggest that after confirming the diagnosis, early vaccination of most of the population (>75%) is critical to decrease the spread of the virus and minimize its impact on pig productivity. The direct economic cost of an outbreak of Aujeszky’s disease can be extremely high on a previously uninfected farm (from 352–792 Euros/sow/year) and highlights the positive benefits of investing in vaccination measures to control infections. We demonstrate the usefulness of computational models as tools in the evaluation of preventive medicine programs aimed at limiting the impact of disease on animal production.

Portuguese Local Pig Breeds: Genotype Effects on Meat and Fat Quality Traits.

Simple SummaryLocal breeds are generally associated with slower growth rates, higher slaughter weights, and fatter carcasses due to genetic and rearing system characteristics. When compared to intensive pig production systems, those based on European local breeds generally provide a more favourable response to the required increase in the production of high-quality pork and pork products in sustainable chains, meeting consumer demands. Reducing costs and improving the economic viability of production systems while preserving the quality of the products obtained is of vital importance. In this work, we propose that Portuguese local pig production chains could improve their performance and productivity without compromising the quality of the final product by crossing local breeds instead of crossing with modern breeds. This could help to maintain or increase local breed populations, supporting conservation of animal biodiversity.This work investigated the contribution of cross-breeding between two local Portuguese pig breeds to the conservation of animal biodiversity and income of local pig producers. Quality traits of semimembranosus (SM), gluteus medius (GM) and dorsal subcutaneous fat (DSF) were studied in Alentejano (AL), Bísaro (BI), AL × BI, and BI × AL (Ribatejano—RI) castrated male pigs. Pigs were reared outdoors, fed ad libitum, and slaughtered at ~65 (trial 1) and 150 kg BW (trial 2). In trial 1, AL pigs showed higher SM intramuscular fat, lower total collagen, and higher soluble collagen than BI pigs, while AL × BI and BI × AL pigs showed intermediate (NS) values. AL, AL × BI, and BI × AL pigs showed higher SM myoglobin content, and AL a more intense red colour than BI pigs. Finally, AL, AL × BI, and BI × AL showed higher total lipids in DSF than BI pigs. In trial 2, SM and DSF results were similar to those obtained in trial 1. In GM, AL and BI × AL showed higher intramuscular fat than BI and AL × BI pigs, while AL, AL × BI and BI × AL showed lower total collagen content than BI pigs. In conclusion, these results suggest that RI crosses are a productive alternative, with overall muscle and DSF traits statistically not different between AL × BI and BI × AL, and similar to those observed in AL pigs.

Cost-effectiveness of environmental impact abatement measures in a European pig production system

Many emerging technologies and alternative farm management practices have the potential to improve the sustainability of pig production systems. The implementation of such practices is not always economically viable. The goal of this study was to assess the cost-effectiveness of such environmental mitigation strategies in pig systems, using an Environmental Abatement Cost analysis. We considered four pig housing (improved insulation, increased ventilation efficiency, frequent slurry removal, increased slurry dilution) and three manure management related abatement strategies (anaerobic digestion, slurry acidification, slurry separation), implemented as stand-alone and as a set of “pig housing–pig housing” and “pig housing–manure management” combinations. We calculated their annual equivalent value through a discounted cash flow analysis and then their annualised abatement potential through a cradle-to-farm gate life cycle assessment. The baseline system against which the analysis was conducted was a typical Danish pig production system, over a 25-year time horizon. The environmental impact categories considered were Non-Renewable Resource Use (NRRU), Non-Renewable Energy Use (NREU), Global Warming Potential (GWP), Acidification Potential (AP) and Eutrophication Potential (EP). Pig housing–anaerobic digestion combinations were the most cost-effective options for GWP, NRRU and NREU. Their abatement costs ranged from −€0.237 to €0.70 per tonne CO2 eq., −€0.146 to €0.36 per g Sb eq. and -€1.75−04 to €3.11−04 per GJ abated respectively. Anaerobic digestion was the most cost-effective stand-alone investment for GWP (−€0.206 per tonne CO2 eq.), NRRU (−€0.0493 per g Sb eq.) and NREU (−€1.00−04 per GJ), and slurry acidification for AP (€303 per tonne SO2− eq.) and EP (€1190 per tonne PO43− eq.) mitigation. Overall, measures for mitigation of GWP, NRRU and NREU required higher investments than for AP and EP, but also generated profit. The framework developed in this study can potentially aid decision making in the choice of environmentally and economically sustainable pig system modifications.

Combining conventional and participatory approaches to identify and prioritise management and health-related constraints to smallholder pig production in San Simon, Pampanga, Philippines

Pork is the main meat produced and consumed in the Philippines. The majority of pigs are raised by smallholders who experience a range of constraints to their pig production. This study presents the findings of the first part of an overarching project that used an Ecohealth approach and aimed to improve the production and competitiveness of the smallholder pig system in an area of the Philippines. A participatory approach was embraced, combining conventional and participatory epidemiology methods followed by a stakeholder discussion. The first aim was to identify management and health-related constraints to pig production among smallholder famers in San Simon, Pampanga, Philippines. The second aim was for the project team and stakeholders to jointly prioritise activities for the immediate future to address these constraints. Key management and health-related constraints identified included inadequate water supply to pigs, particularly lactating and gestating sows, and a range of feeding-related issues. Diarrhoea was recognised as the disease syndrome of highest priority and limited record keeping meant that farmers were unable to assess the productivity and profitability of their pig farming enterprises. Actions jointly prioritised by stakeholders and the project team were: the appointment of a project coordinator within each barangay; conduct two sets of seminars, the first covering water and nutrition and the second piglet management and diarrhoea, to be delivered by technical experts but with farmer “trusted sources” also sharing their experiences; development of easily understandable leaflets and posters covering key technical information; promotion of nipple drinkers attached to five-gallon water containers and creep boxes for piglets, and conduct of a record keeping workshop with a small group of innovative farmers to develop a useful and usable tool for record keeping. The use of multiple approaches to data-gathering enabled triangulation of study findings. Without any one of these components the understanding of the pig production system would have been less complete and it is possible that the proposed actions would not have been as well-tailored to the needs of the farmers. The participatory approach, in particular the stakeholder discussion, provided the opportunity to embrace the “deciding together” and “acting together” stances of participation rather than the lower “information giving” stance, thereby giving stakeholders greater ownership of the future activities of the overarching project and beyond.

Mitigation potential for carbon and nitrogen emissions in pig production systems: lessons from the North China Plain

China produces approximately half of the world’s pork at a high environmental cost. Implementing mitigation measures requires a better understanding of pig farming systems that are often diverse in practice. Nutrient uses and losses can be largely altered due to these variations but have not, however, been fully evaluated; moreover, attention is rarely paid to pollution swapping. Our study evaluated carbon (C) and nitrogen (N) flows among pig farms on the North China Plain using the mass flow approach. The impacts of advanced mitigation measures on nitrogen use efficiency (NUE) and on C and N emissions were further analyzed via scenario analyses. The results showed that large variations among farms were observed by comparing the best-performing farms (“top 20%”) with the “other” farms; the comparisons showed 31.3 vs. 21.3% for the system NUE, 3.0 vs. 5.7 kg N ·100 kg liveweight gain (LWG)−1 for manure N losses, and 108.1 vs. 146.4 kg CO2-eg·100 kg LWG−1 for greenhouse gas (GHG) emissions, respectively. Lower system NUE was caused by lower NUEs of pigs, followed by high N emissions from manure and excessive manure application. Scenario analyses indicated that the total N loss of systems can be mitigated by 10–13% through dietary manipulation and by 26%, 27%, and 13% by low-emission storage, biogas production with improved storage, and balanced fertilization, respectively. Anaerobic digestion was solely effective for GHG mitigation (46% reduction), but no impacts were observed for all other low-NH3 measures. Combining mitigation measures simultaneously decreased total N and GHG losses by 56% and 54%, respectively, and increased the system NUEs by 89%. The wide variations among farms suggest largely attainable improvements in productivity and nutrient use by closing the management gaps related to these factors. Proper combinations of advanced measures are further needed to achieve more effective mitigation goals for multiple pollutants.

Performance of Doom pigs under different production systems in subtropical ecosystem of north east India

Doom pig is a newly registered indigenous breed from subtropical ecosystem of north east India. This breed adapt well to the harsh agro-climatic condition with minimum input. The population of this pig breed showed a declining trend, mainly due to high rate of crossbreeding, lack of breeding policy and lacunae in production system. Under field condition, the farmers follow two different types of production systems, viz. migratory scavenging and backyard production system. Doom pigs reared under backyard production system has higher growth performance and carcass yield. However, pigs in migratory scavenging system have better reproductive efficiency and quality pork yield. Therefore, it can be concluded from the present study that backyard production system is more suitable for fattener pig production and migratory scavenging system for breeding pig production. The results from this study can be suitably exploited to design conservation and breeding strategies for newly registered Doom pigs of north east India.

Short-term choice of fattening pigs for additional plant-based materials

A major problem in conventional pig production systems is the occurrence of abnormal behaviours such as tail biting. Tail biting is a multifactorial problem, but it seems that a lack of proper enrichment materials prevents the animals from performing normal species-specific behaviour, e.g., rooting, nosing or chewing, and thus increases the prevalence of tail biting. The aim of this study was to identify plant-based enrichment material and nutritive additives that are attractive to pigs and that can be used as enrichment in practice. Therefore, we carried out two choice tests to investigate (i) which plant-based enrichment materials, differing in structure and flavour, pigs prefer and (ii) what kind of nutritive additives can be used to further increase the attractiveness of plant-based enrichment materials. In each choice test, pigs had the choice of six offered options. Pigs were tested individually in their familiar environment in an arena for 150 s. The first choice test revealed that pelletized materials, i.e., lucerne pellets and straw pellets, were preferred over all other options tested (Friedman test, n = 55, p < 0.001). In the second choice test, the pigs’ interest was highest for the largest nutritive additive, i.e., maize kernels, compared to the other options tested (Friedman test, n = 65, p < 0.001). When choosing enrichment materials for pigs, structure, size and flavour should be considered. Pelletized plant-based enrichment materials or non-pelletized materials with nutritive additives can be recommended to stimulate exploration. Further studies should examine the interval at which enrichment material needs to be altered to keep pigs’ interest at a high level.

Removal of High Concentrations of Veterinary Antibiotics Through Co-composting of Swine Waste

The increasing demand for animal protein, mainly for porcine protein, has led companies and producers to investigate techniques capable of optimizing current production systems, as well as the use of drugs such as veterinary antibiotics. The incomplete absorption of these drugs by the digestive system of the animals generates effluents whose composition presents veterinary drug residues. Swine waste treatment systems (ponds) have reduced capacity to degrade these residues; thus, it is necessary to find treatment alternatives such as composting. Therefore, the aim of the current study was to evaluate the effectiveness of the composting technique in degrading 17 veterinary antibiotics often used in pig production systems. The herein adopted composting process comprised eucalyptus shavings and swine waste at the ratio 1:8 (1 kg of shavings to 8 L of swine waste). First, 25 L of swine waste were contaminated with 17 antibiotics and mixed in a bench-scale composting system for 150 days. The sample preparation consisted of the solid-liquid extraction followed by a clean-up by dispersive solid phase extraction, and then the extracts were analyzed by ultra-high performance liquid chromatography tandem mass spectrometry. Antibiotic groups such as quinolones, tetracyclines, and sulfonamides recorded fractions cumulative removal of 99.4%, 99.4% and 97.2%, respectively, at the end of the composting process. On the other hand, antibiotics such as sulfathiazole, chlortetracycline, and tetracycline recorded 100% degradation during the composting process.

African Swine Fever Epidemiology and Control.

African swine fever is a devastating disease that can result in death in almost all infected pigs. The continuing spread of African swine fever from Africa to Europe and recently to the high-pig production countries of China and others in Southeast Asia threatens global pork production and food security. The African swine fever virus is an unusual complex DNA virus and is not related to other viruses. This has presented challenges for vaccine development, and currently none is available. The virus is extremely well adapted to replicate in its hosts in the sylvatic cycle in East and South Africa. Its spread to other regions, with different wildlife hosts, climatic conditions, and pig production systems, has revealed unexpected epidemiological scenarios and different challenges for control. Here we review the epidemiology of African swine fever in these different scenarios and methods used for control. We also discuss progress toward vaccine development and research priorities to better understand this complex disease and improve control.

Viabilidad económica en construcción e implementación de biodigestores y lagunas de oxidación en la porcicultura

The aim of this study was evaluating the build and implantation costs of biodigester and deep pit recovered by PVC or PEAD geomembrane, to store the swine waste and use it to generate extra revenue for the system. Three swine production scale representatives to São Paulo state (small pig production size: 300 housed sows; medium pig production size: 650 housed sows; large pig production size) was simulated to estimate the waste pig production and biogas as well as electric power. To simulation development, were used scientific literature and cost identification of biodigester and deep pit build items from mesoregion of Campinas, SP. The base attractive rate used was 10% a year and the time frame were 20 years. By the cash flow were determinate the internal rate of return (IRR), net present value, payback and the profitability rate to each situation. The economic analysis of waste management systems demonstrated that deep pit implantation was most cost-effective to small pig production size when compared to biodigester implantation. However, to medium and large pig production size the simulation results showed that biodigester implantation was better due to higher waste production in higher pig production systems. This provided higher fertilizer and biogas production than can be turned in electric power; result in revenue for these production systems. However, if considered the pig manure valuation as equity to commercial fertilizer, until the easiest pig manure storage system become cost-effective due to add its greatness value by your fertilizing potencial.

Late weaning is associated with increased microbial diversity and Faecalibacterium prausnitzii abundance in the fecal microbiota of piglets

BackgroundIn pig production systems, weaning is a crucial period characterized by nutritional, environmental, and social stresses. Piglets transition from a milk-based diet to a solid, more complex plant-based diet, and their gut physiology must adapt accordingly. It is well established that piglets weaned later display improved health, better wean-to-finish growth performance, and lower mortality rates. The aim of this study was to evaluate the impact of weaning age on fecal microbiota diversity and composition in piglets. Forty-eight Large White piglets were divided into 4 groups of 12 animals that were weaned at different ages: 14 days (early weaning), 21 days (a common weaning age in intensive pig farming), 28 days (idem), and 42 days (late weaning). Microbiota composition was assessed in each group by sequencing the 16S rRNA gene using fecal samples taken on the day of weaning, 7 days later, and at 60 days of age.ResultsIn each group, there were significant differences in fecal microbiota composition before and after weaning (p < 0.05), confirming that weaning can drastically change the gut microbiota. Microbiota diversity was positively correlated with weaning age: microbial alpha diversity and richness were higher in piglets weaned at 42 days of age both on the day of weaning and 7 days later. The abundance of Faecalibacterium prausnitzii operational taxonomic units (OTUs) was also higher in piglets weaned at 42 days of age.ConclusionsOverall, these results show that late weaning increased gut microbiota diversity and the abundance of F. prausnitzii, a microorganism with positive effects in humans. Piglets might thus derive a competitive advantage from later weaning because they have more time to accumulate a higher diversity of potentially beneficial microbes prior to the stressful and risky weaning period.

Life Cycle Assessment of Iberian Traditional Pig Production System in Spain

Traditional Iberian pig production is characterized by outdoor systems that produce animals fed with natural resources. The aim of this study was to assess the environmental impacts of such systems through Life Cycle Assessment. Environmental impacts were analysed per kilogram of live weight at farm gate. Iberian pig production in montanera had the lowest impacts for climate change (CC), acidification (AC), eutrophication (EU) and cumulative energy demand (CED), being 3.4 kg CO2 eq, 0.091 molc H+ eq, 0.046 kg PO43− eq, and 20.7 MJ, respectively, due to the strict use of natural resources (acorns and grass) during the fattening period. As Iberian farms had a greater dependence on compound feed in cebo campo, environmental impacts on CC, AC, EU and CED were 22, 17, 95 and 28% higher, respectively, than with montanera. For land occupation (LO), however, cebo campo had a lower impact (31.6 m2·year) than montanera (43.0 m2·year) system. Traditional Iberian pig production systems have environmental impacts higher than conventional systems studied in literature but are similar to other traditional systems. Based on the present assessment, it is necessary to account for the contribution of emissions resulting from the consumption of natural resources to avoid the underestimation of environmental impacts.

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.

Trichinella britovi as a risk factor for alternative pig production systems in Greece and Europe.

Trichinellosis is an important zoonosis and the most common source of human infection is meat from pigs and wild boars. The European Union (EU) supports alternative pig production systems (organic and free-ranging) as sustainable farming systems. However, these systems that allow outdoor access for farm animals, may create new or reintroduce old risks to public health. During the last years, alternative pig production systems (free-ranging or organic pig) are growing in popularity in Greece due to the increasing interest of consumers for organic products. The majority of the trichinellosis outbreaks in the EU were associated with pork and meat products including wild boars. In Greece, from 2009 to 2012, 37 Trichinella spp. positive free-ranging pigs were reported in free-ranging pig farms of Northern-Eastern Greece (31 were identified as T. britovi). The recent re-emerging present of the Trichinella spp. infections in free-ranging pigs and wild boars are a high risk for the consumers and should alarm the Public Health Authorities in Greece and the EU. During the last years, the organic or free-ranging pig production systems are growing in popularity in the EU. However, these systems increase the risk of Trichinella spp. infections, since pigs are possible to be infected by feeding on carcasses or the offal of hunted or dead wild animals. For this reason, it is important for Public Health Authorities to be focused on the training of hunters and farmers in order to avoid the transmission among free-ranging pigs and prevent the cases of human infection.

Mycoplasmal pneumonia of swine: Update and importance of the disease

The paper provides an overview of updated knowledge on this common disease with a strong impact on pig production efficiency. Mycoplasma hyopneumoniae (Mhp), the etiologic agent of the condition, is the smallest self-replicating bacteria, distinguished from most other bacteria by the lack of a cell wall. Colonization of the respiratory cilia is a unique feature of Mhp, which results in a persistent presence of Mhp in the airways and creates a population of infected asymptomatic animals that continually expose other pigs to infection. The economic consequences of a long-term persistence of infection within the herd include a chronic reduction in feed efficiency and increased opportunity for co-infection with other respiratory pathogens, leading to PRDC (porcine respiratory disease complex) syndrome. Chronic Mhp infection in the form of a respiratory disease with high morbidity and low mortality has been estimated to affect up to 70% of pigs worldwide. Diagnostic tools include clinical diagnosis, examination of gross lesions and histopathology. Mycoplasma hyopneumoniaespecific laboratory tests are critical to identify asymptomatic carriers or to detect antibodies as a sign of endemic infection. Tools that demonstrate the presence of Mhp rely on visualizing the organism (culture, FIA) or on detection of nucleic acid (PCR) or antigen specific for that pathogen (ELISA). Control of Mycoplasma hyopneumoniae has been attempted by several widely practiced methods. These include sow vaccination programmes, early vaccination of suckling piglets, use of antibiotics at peak transmission times, introduction of piglet flow in the all-in/all-out system and a segregated system of pig production. Several Mhp elimination protocols have been developed and can be implemented to eradicate this pathogen from the herd. One of them is a partial depopulation procedure, which consists in depopulation of pigs below 9 months of age. The other animals are subjected to medication.

Propuesta gastronómica con Cavia porcellus

Cavia porcellus is used as a kind of meat supply, it is part of the diet and source of sustenance in some regions of the world. In Mexico guinea pig production systems represent an opportunity to produce meat for self-consumption and even for local sale. The objective of this study was to evaluate sensorially the gastronomic proposal based on C. porcellus meat; which consisted of four stews (in mushroom cream, roasted, sweet and sour marinade and in yellow mole) and were tasted by 40 judges not trained by an acceptability test with a structured scale of hedonic satisfaction, the attributes considered were the appearance, smell, taste, tenderness and juiciness. Data were analysed using an Ascendant Hierarchical Classification and Principal Component Analysis to construct the quadratic mapping model of external preferences. The results indicated that for type 2 consumers there is a significant effect (R2=0.976, p<0.05), determining their general acceptance in common by guinea pig cream mushrooms. It was concluded that the gastronomic proposal of the four guinea pig stews was accepted, but the most widely accepted was the cuy in cream of mushroom soup.

Small-mammal assemblages in piggeries in a developing country: relationships with management practices and habitat complexity

Abstract ContextPig production is increasing in developing countries and is increasing the coexistence of different production systems regarding management practices. Small mammals can cause major economic and sanitary problems on pig farms. The interactions among small mammals, production practices and habitat complexity have been sparsely studied. AimsThe aim was to compare small-mammal assemblages on extensive and intensive pig-production systems, and to analyse the relationship with environmental characteristics and management practices. MethodsSeasonal live-trapping of small mammals within 18 farms (under intensive or extensive management) was performed in central Argentina, simultaneously with a survey of environmental and management practices. Multiple regression analyses were performed to assess the relation between infestation levels and environmental characteristics. Key results In total, 472 small mammals were captured, including the exotic murids Rattus norvegicus, R. rattus and Mus musculus, three native sigmodontines, namely, Akodon azarae, Oligoryzomys flavescens and Oxymycterus rufus, and two native marsupials, namely, Didelphis albiventris and Lutreolina crassicaudata. The location of waste deposits, the density of cats, the frequency of rodent control and the way pig food was stored influenced wild small-mammal abundance; exotic rodent species were lower when the density of cats increased. Rattus norvegicus was more abundant where rodent control was not frequent or null, contrary to M. musculus. Both species were more abundant in food and pig sheds, whereas native species were associated with vegetated areas outside of sheds. Also, A. azarae was associated with the density of pigs. Didelphis albiventris was more abundant on extensive farms, whereas L. crassicaudata was captured on intensive farms. Conclusions Small-mammal abundance did not respond to the type of production system per se, but exotic species abundance was influenced by management decisions. The most important human behaviours related to exotic rodent infestation were the possession of cats, the frequency of rodent control and the way waste and pig feed were managed. Implications Our findings highlighted the need for integrated studies on factors influencing the dynamics of rodent populations in commercial piggery systems, for the development of effective pest management. Management recommendations need to assess environmental complexity and human behaviour as important moderators of the population dynamics of small mammal species in and around piggeries.

Use of organic coagulant/flocculant for treatment of effluents generated in intensive rearing of swine

AbstractSeparation of water for reuse is essential in an effluent treatment system, especially in activities with high water consumption, such as a pig production system. The objective of this work was to evaluate the efficiency of Tanfloc SG® coagulant tannin/organic flocculant used to treat effluent generated during the intensive rearing of swine. For the evaluation, laboratory and in situ tests (field test) were performed. The laboratory tests were performed to define the concentration (1 and 16%), dosage (0, 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, 2.0, 4.0, 8.0, and 16.0 milliliters of the solution), and time (24, 48, 72, and 96 hours) of coagulation/flocculation treatment of the solid portion of the effluent. The parameters pH, turbidity, oxidation reduction potential, dissolved oxygen, and electroconductivity (in microsiemens per centimeter) were evaluated using a multiparameter probe and the parameters ammonia (NH3), nitrate (NO3), and nitrite (NO2) in the laboratory, in relation to the coagulation/flocculation time of the solid part of the effluent. The use of tannin as a coagulant/flocculant of plant origin in the treatment of swine effluents was effective in reducing turbidity and concentrations of ammonia, nitrite, and nitrate, and it allowed separation of the solid–liquid phase in approximately 68% as liquid phase.

Network analysis of swine movements in a multi-site pig production system in Iowa, USA

Pig production in the United States is based on multi-site systems in which pigs are transported between farms after the conclusion of each particular production phase. Although ground transportation is a critical component of the pork supply chain, it might constitute a potential route of infectious disease dissemination. Here, we used a time series network analysis to: (1) describe pig movement flow in a multi-site production system in Iowa, USA, (2) conduct percolation analysis to investigate network robustness to interventions for diseases with different transmissibility, and (3) assess the potential impact of each farm type on disease dissemination across the system. Movement reports from 2014–2016 were provided by Iowa Select Farms, Iowa Fall, IA. A total of 76,566 shipments across sites was analyzed, and time series network analyses with temporal resolution of 1, 3, 6, 12, and 36 months were considered. The general topological properties of networks with resolution of 1, 3, 6, and 12 months were compared with the whole period static network (36 months) and included the following features: number of nodes and edges, degree assortativity, density, average path length, diameter, clustering coefficients, giant strongly connected component, giant weakly connected component, giant in component, and giant out component. Small-world and scale-free topologies, centrality parameters, and percolation analysis were investigated for the networks with 1-month window. Networks’ robustness to interventions was assessed by using the Basic Reproduction Number (R0). Centrality parameters indicate that gilt development units (GDU), nursery, and sow farms have more central role in the pig production hierarchical structure. Therefore, they are potentially major factors of introduction and spread of diseases over the system. Wean-to-finishing and finishing sites displayed high in-degree values, indicating that they are more susceptible to be infected. Percolation analysis combined with general properties (i.e. heavy-tailed distributions and degree disassortative) suggested that networks with 1-month time resolution were highly responsive to interventions. Furthermore, the characteristics of a disease should have strong implications in the biosecurity practices across production sites. For instance, biosecurity practices should be focused on sow farms for highly contagious disease (e.g., foot and mouth disease), while it should target nursery sites in the case of a less contagious diseases (i.e. mycobacterial infections). Understanding the patterns of swine movements is crucial for the swine industry decision-making in the case of an epidemic, as well as to design cost-effective approaches to monitor, prevent, control and eradicate infectious diseases in multi-site systems.