Investigating the role of free-ranging wild boar (Sus scrofa) in the re-emergence of enzootic pneumonia in domestic pig herds: a pathological, prevalence and risk-factor study

Enzootic pneumonia (EP) caused by Mycoplasma hyopneumoniae has a significant economic impact on domestic pig production. A control program carried out from 1999 to 2003 successfully reduced disease occurrence in domestic pigs in Switzerland, but recurrent outbreaks suggested a potential role of free-ranging wild boar (Sus scrofa) as a source of re-infection. Since little is known on the epidemiology of EP in wild boar populations, our aims were: (1) to estimate the prevalence of M. hyopneumoniae infections in wild boar in Switzerland; (2) to identify risk factors for infection in wild boar; and (3) to assess whether infection in wild boar is associated with the same gross and microscopic lesions typical of EP in domestic pigs. Nasal swabs, bronchial swabs and lung samples were collected from 978 wild boar from five study areas in Switzerland between October 2011 and May 2013. Swabs were analyzed by qualitative real time PCR and a histopathological study was conducted on lung tissues. Risk factor analysis was performed using multivariable logistic regression modeling. Overall prevalence in nasal swabs was 26.2% (95% CI 23.3-29.3%) but significant geographical differences were observed. Wild boar density, occurrence of EP outbreaks in domestic pigs and young age were identified as risk factors for infection. There was a significant association between infection and lesions consistent with EP in domestic pigs. We have concluded that M. hyopneumoniae is widespread in the Swiss wild boar population, that the same risk factors for infection of domestic pigs also act as risk factors for infection of wild boar, and that infected wild boar develop lesions similar to those found in domestic pigs. However, based on our data and the outbreak pattern in domestic pigs, we propose that spillover from domestic pigs to wild boar is more likely than transmission from wild boar to pigs.

[Evaluation of risk factors for Mastitis-Metritis-Agalactia in pig farms in Switzerland].

Mastitis-Metritis-Agalactia (MMA), also known as postpartum dysgalactia syndrome (PPDS) is the most important disease complex in sows after birth. The present study compared 30 MMA problem herds (over 12% of farrowing sows affected) with 30 control farms (less than 10% of farrowing sows affected) to identify risk factors and treatment incidence. Important risk factors identified were in gilts the integration into the herd after the first farrowing, in gestating sows firm fecal consistency as well as in lactating sows soiled troughs, a low flow rate (<2 liters per minute) in drinking nipples and a high prevalence of lameness. The treatment incidence was also significantly different between the two groups. The MMA prevalence could be reduced through optimization of husbandry, feeding and management, which could essentially diminish the use of antibiotics.

Longitudinal study on the colonisation and transmission of methicillin-resistant Staphylococcus aureus in pig farms.

Knowledge about the dynamics of methicillin-resistant Staphylococcus aureus (MRSA) in pigs lacks detail at the level of individual animal. The aim of our study was therefore to determine the colonisation status of MRSA in individual pigs from birth to slaughter in order to gain a better understanding of substantial factors involved in transmission. Two farrow-to-finish and two grow-to-finish herds were included in the study. A total of 1728 nasal swabs from 390 pigs and 592 environmental wipes were collected at 11 different time points. Intermittent colonisation throughout the entire production cycle was conspicuous in the tracking of MRSA in individual pigs. Almost all pigs from a MRSA-positive herd changed MRSA status several times, which implies that pigs are transiently rather than permanently colonised. We highly recommend the definition of MRSA status at herd level rather that at the level of the individual pig when considering prevention measures against MRSA. Therefore, to avoid the further spread of MRSA in countries with moderate prevalence, such as in Switzerland, defining farms as MRSA positive or MRSA negative and allowing the trade of pigs only within herds of the same status seems feasible. This will also be important for combating the further dissemination of livestock-associated (LA)-MRSA into healthcare facilities and the community via humans who have close contact with animals.

Effects of asbestos and silica on superoxide anion production in the guinea pig alveolar macrophage

Asbestos and silica are important industrial hazards. Exposure to these dusts can result in pulmonary fibrosis and, in the case of asbestos, cancer. Although the hazards of asbestos and silica exposure have long been known, the pathogenesis of dust-related disease is not well understood. Both silica and asbestos are thought to alter the function of the alveolar macrophage, but the nature of the biochemical alteration is unknown. Therefore, this study examined the effect of asbestos and silica on the activation pathway of the guinea pig alveolar macrophage. Activation of macrophages by physiological agents results in stimulation of phospholipase C causing phosphatidyl inositol turnover and intracellular calcium mobilization. Phosphatidyl inositol turnover produces diacylglycerol which activates protein kinase C causing superoxide anion production.^ Chrysotile stimulated alveolar macrophages to produce superoxide anion. This stimulation proceeded via phospholipase C, since chrysotile stimulated phosphatidyl inositol turnover and intracellular calcium mobilization. The possible involvement of a coupling protein was evaluated by pretreating cells with pertussis toxin. Pertussis toxin pretreatment partially inhibited chrysotile stimulation, suggesting that chrysotile activates a coupling protein in an non-classical manner. Potential binding sites for chrysotile stimulation were examined using a series of nine lectins. Chrysotile-stimulated superoxide anion production was blocked by pretreatment with lectins which bound to N-acetylglucosamine, but not by lectins which bound to mannose, fucose, or N-acetylgalactosamine. In addition, incubation with the N-acetylglucosamine polymer, chitin, inhibited chrysotile-stimulated superoxide anion production, suggesting that chrysotile stimulated superoxide anion production by binding to N-acetylglucosamine residues.^ On the other hand, silica did not stimulate superoxide anion production. The effect of silica on agonist stimulation of this pathway was examined using two stimulants of superoxide anion production, N-formyl-nle-leu-phe (FNLP, which stimulates through phospholipase C) and phorbol-12,13-dibutyrate (which directly activates protein kinase C). Sublethal doses of silica inhibited FNLP-stimulated superoxide anion production, but did not affect phorbol-12,13-dibutyrate-stimulated superoxide anion production, suggesting that the site of inhibition precedes protein kinase C. This inhibition was not due to cell membrane damage, since cell permeability to calcium-45 and rubidium-86 was not increased. It is concluded that chrysotile binds to N-acetylglucosamine residues on macrophage surface glycoproteins to stimulate the physiological pathway resulting in superoxide anion production. In contrast, silica does not stimulate superoxide anion production, but it did inhibit FNLP-stimulated superoxide anion production. ^

Effects of Bedding on Pig Performance

More pigs are being produced in bedded systems such as hoop barns due to the increase in demand for niche pork. Most of the current swine nutrition information has been generated in confinement settings without bedding. As omnivores, pigs ingest some bedding. There are questions about the effects of the ingested bedding on growth and feed utilization by the modern market pig. More knowledge in this area will allow for more accurate feed formulation in bedded systems.

Qué autonomía es posible en una empresa recuperada? : Reflexiones en torno a la organización productiva y del trabajo en la Cooperativa de Trabajo Textiles Pigüé

Si en las empresas recuperadas por sus trabajadores desaparece la figura del capitalista y de sus cuadros técnicos al interior del espacio productivo, disipándose el control directo del capital sobre el proceso de trabajo, éstas se ven en general presionadas a vincularse con el mercado para poder subsistir, debiendo entonces ajustarse a condiciones impuestas por la competitividad. Muchas empresas recuperadas se vinculan con el mercado como tercerizadoras, involucrándose en los extendidos procesos de descentralización y flexibilización de la producción que adoptan diversas empresas al subcontratar procesos para reducir costos. En ése marco, se analizará en profundidad el funcionamiento de la Cooperativa de Trabajo Textiles Pigüé, empresa proveniente de un proceso de recuperación por sus trabajadores. En este estudio se pretende examinar en qué sentido la autogestión posibilitaría que los trabajadores logren mayor autonomía frente al capital; considerando que autonomizarse no es despojarse de un capitalista particular sino lograr actuar con principios propios frente a los dictados/exigencias del capital. En relación con ello se platean los siguientes interrogantes: ¿Es posible que los trabajadores recobren la autonomía?, ¿hasta qué punto?, ¿qué posibilidad tienen de poder organizar su trabajo según criterios y necesidades propios?. Para dar cuenta de los objetivos de este trabajo, además de realizar una revisión bibliográfica sobre la temática, se recurrió a un abordaje metodológico cualitativo, utilizando las técnicas de entrevista, observación participante y análisis de fuentes secundarias

Qué autonomía es posible en una empresa recuperada? : Reflexiones en torno a la organización productiva y del trabajo en la Cooperativa de Trabajo Textiles Pigüé

Si en las empresas recuperadas por sus trabajadores desaparece la figura del capitalista y de sus cuadros técnicos al interior del espacio productivo, disipándose el control directo del capital sobre el proceso de trabajo, éstas se ven en general presionadas a vincularse con el mercado para poder subsistir, debiendo entonces ajustarse a condiciones impuestas por la competitividad. Muchas empresas recuperadas se vinculan con el mercado como tercerizadoras, involucrándose en los extendidos procesos de descentralización y flexibilización de la producción que adoptan diversas empresas al subcontratar procesos para reducir costos. En ése marco, se analizará en profundidad el funcionamiento de la Cooperativa de Trabajo Textiles Pigüé, empresa proveniente de un proceso de recuperación por sus trabajadores. En este estudio se pretende examinar en qué sentido la autogestión posibilitaría que los trabajadores logren mayor autonomía frente al capital; considerando que autonomizarse no es despojarse de un capitalista particular sino lograr actuar con principios propios frente a los dictados/exigencias del capital. En relación con ello se platean los siguientes interrogantes: ¿Es posible que los trabajadores recobren la autonomía?, ¿hasta qué punto?, ¿qué posibilidad tienen de poder organizar su trabajo según criterios y necesidades propios?. Para dar cuenta de los objetivos de este trabajo, además de realizar una revisión bibliográfica sobre la temática, se recurrió a un abordaje metodológico cualitativo, utilizando las técnicas de entrevista, observación participante y análisis de fuentes secundarias

Qué autonomía es posible en una empresa recuperada? : Reflexiones en torno a la organización productiva y del trabajo en la Cooperativa de Trabajo Textiles Pigüé

Si en las empresas recuperadas por sus trabajadores desaparece la figura del capitalista y de sus cuadros técnicos al interior del espacio productivo, disipándose el control directo del capital sobre el proceso de trabajo, éstas se ven en general presionadas a vincularse con el mercado para poder subsistir, debiendo entonces ajustarse a condiciones impuestas por la competitividad. Muchas empresas recuperadas se vinculan con el mercado como tercerizadoras, involucrándose en los extendidos procesos de descentralización y flexibilización de la producción que adoptan diversas empresas al subcontratar procesos para reducir costos. En ése marco, se analizará en profundidad el funcionamiento de la Cooperativa de Trabajo Textiles Pigüé, empresa proveniente de un proceso de recuperación por sus trabajadores. En este estudio se pretende examinar en qué sentido la autogestión posibilitaría que los trabajadores logren mayor autonomía frente al capital; considerando que autonomizarse no es despojarse de un capitalista particular sino lograr actuar con principios propios frente a los dictados/exigencias del capital. En relación con ello se platean los siguientes interrogantes: ¿Es posible que los trabajadores recobren la autonomía?, ¿hasta qué punto?, ¿qué posibilidad tienen de poder organizar su trabajo según criterios y necesidades propios?. Para dar cuenta de los objetivos de este trabajo, además de realizar una revisión bibliográfica sobre la temática, se recurrió a un abordaje metodológico cualitativo, utilizando las técnicas de entrevista, observación participante y análisis de fuentes secundarias

The aggressiveness of pig slurry to cement mortars

The aim was to measure the behaviour of various mortars employed in livestock media in central Spain and to analyse the aggressiveness of pig slurry to cement blended with fly ash mortars. To achieve this, mortar specimens were immersed in ponds storing pig slurry. Mortar specimens, of 40 ? 40 ? 160 mm, were made from four types of cement commonly used and recommended for rural areas. The types were a sulphate-resistant Portland cement and three cements blended in different proportions with fly ash and limestone filler. After 3, 6, 12, 24, 36, 48 and 60 months of exposure, three or four specimens of each cement type were removed from the pond and washed with water. Their compressive strength and microstructure (X-ray diffraction, mercury intrusion pore-symmetry, thermal analysis and scanning electron microscopy) were then measured. Sulphate-resistant Portland cement (SR-PC), found to be more susceptible to degradation due to its greater proportion of macro-pores and increased total porosity, was found not to be suitable for use with livestock. After 60 months of immersion in the pig slurry medium, CEM II-A (40.3%) mortar retained the greatest compressive strength. Mortars with less than 20% replacement of cement by fly ash were found to be the most durable, with the most suitable mechanical behaviour.

Animal feeding strategies to reduce N2O and NH3 emission from surface-applied pig slurry to a grassland soil.

It is estimated that N losses from fertilized crops range between 50-70%, depending on management practices, climate and soil conditions. Ammonia (NH3) emissions following land application of animal manures give rise to a significant proportion of the total NH3 emissions from agricultural sources.

Dietary Fibre in Pig's Diets: Effects on Greenhouse Gas Emissions from Slurry Storage to Field Application

Pig’s slurry is a key source of greenhouse gases (GHG). In Spain, GHG emissions (CH4+ N2O) from pig slurry (storage and land application) accounted in 2011 for 18.4% of total GHG emissions (in CO2- equivalent) of the agriculture sector according to the National Inventory Report (NIR). Slurry composition can be modified through diet manipulation. The aim of this work was to evaluate the effect of different fibre types in fattening pigs’ diets on GHG emissions from pig slurry storage and field application.

Relationship among slurry characteristics and gaseous emissions at different types of commercial Spanish pig farms

This study aimed to analyse several factors of variation of slurry composition and to establish prediction equations for potential methane (CH4) and ammonia (NH3) emissions. Seventy-nine feed and slurry samples were collected at two seasons (summer and winter) from commercial pig farms sited at two Spanish regions (Centre and Mediterranean). Nursery, growing-fattening, gestating and lactating facilities were sampled. Feed and slurry composition were determined, and potential CH4 and NH3 emissions measured at laboratory. Feed nutrient contents were used as covariates in the analysis. Near infrared reflectance spectroscopy (NIRS) was evaluated as a predicting tool for slurry composition and potential gaseous emissions. A wide variability was found both in feed and slurry composition. Mediterranean farms had a higher pH (p<0.001) and ash (p=0.02) concentration than those located at the Centre of Spain. Also, type of farm affected ether extract content of the slurry (p=0.02), with highest values obtained for the youngest animal facilities. Results suggested a buffer effect of dietary fibre on slurry pH and a direct relationship (p<0.05) with fibre constituents of manure. Dietary protein content did not affect slurry nitrogen content but decreased (p=0.003) total and volatile solids concentration. Prediction models of potential NH3 emissions (R2=0.89) and CH4 yield (R2=0.61) were obtained from slurry composition. Predictions from NIRS showed a high accuracy for most slurry constituents (R2>0.90) and similar accuracy of prediction of potential NH3 and CH4 emissions (R2=0.84 and 0.68, respectively) to models using slurry characteristics, which can be of interest to estimate emissions from commercial farms and establish mitigation strategies or optimize biogas production.