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Livestock grazing is the most widespread land management practice in western North America. Seventy percent of the western United States is grazed, including wilderness areas, wildlife refuges, national forests, and even some national parks. The ecological costs of this nearly ubiquitous form of land use can be dramatic. Examples of such costs include loss of biodiversity; lowering of population densities for a wide variety of taxa; disruption of ecosystem functions, including nutrient cycling and succession; change in community organization; and change in the physical characteristics of both terrestrial and aquatic habitats. Because livestock congregate in riparian ecosystems, which are among the biologically richest habitats in arid and semiarid regions, the ecological costs of grazing are magnified in these sites. Range science has traditionally been laden with economic assumptions favoring resource use. Conservation biologists are encouraged to contribute to the ongoing social and scientific on grazing issues.

Slovenia, like other developed countries, is characterized by the fact that the number of farm takeovers is decreasing and farms are not being transferred to successors in a timely manner. As an EU member state, Slovenia is entitled to financial incentives intended to halt or at least ameliorate this trend, but the situation is nonetheless not improving. This article proceeds from the hypothesis that economic factors are not the only ones that affect succession on Slovenian farms. The hypothesis was confirmed in a study limited to mountain farms. It was determined that, although economic factors have a significant effect on succession on Slovenian farms, at the same time other factors also affect this. Among these, the factors that stand out the most are those through which tradition or traditional thought and behavioral patterns are expressed, as well as the factors that express the standpoints, perceptions, and opinions of farm owners.

We monitored the presence of Listeria monocytogenes in environmental sources and evaluated phenotypic and molecular characteristics of the isolates recovered. L. monocytogenes was isolated in 12 of the 107 samples from wild and farm environments, and from vegetation. Most isolates (83.3%) were of serotype 1/2a and the remainder (2) were of serotype 4b. All 12 isolates were susceptible to the whole range of antimicrobials tested. These 12 strains were carriers of the virulence genes prfA, hlyA, actA, plcA, plcB, inlA, inlB, inlC, and inlJ. The detection of the inlA gene in 4 strains using the PCR-RFLP suggests the potential of some of these strains to penetrate into epithelial cells of the intestinal barrier. Macrorestriction analysis also confirmed clonal identity of some environmental isolates with food and human isolates. These results indicate that the external environment is a source of potentially pathogenic strains of L. monocytogenes.

A total of 46 Listeria spp. were isolated from 719 samples (milk, bulk tank swabs, cheese, feed, water, faeces and the environment) collected from 415 cattle and 304 sheep over 12 months (from February 2007 to January 2008). These isolates were identified by conventional and PCR techniques as belonging to L. monocytogenes (17.4%), to Listeria innocua (39.1%), to Listeria seeligeri (17.4%), to Listeria grayi (15.2%) and to Listeria welshimeri (11%). No Listeria ivanovii were isolated from any of the samples. Listeria spp. were not isolated from cheese and bulk tank swabs. With regard to seasonal variations most Listeria spp. were isolated in the spring and winter seasons. The eight L. monocytogenes isolates were characterized by PCR-RFLP with AluI and Tsp509I. RFLP typing of the isolates revealed two different profiles with both restriction enzymes. Four and six different profiles were produced in the examination of L. monocytogenes isolates with RAPD analysis with HLWL74 and HLWL85 primers, respectively. This is the first report on the genotyping of L. monocytogenes isolates from various sources in Turkey. This study has highlighted the need for improved control and epidemiologic strategies to prevent the transmission of Listeria spp. to animals and humans.

More than one hundred volatile organic substances were identified by gas chromatography and mass spectrometry (GC/MS) in the indoor and outdoor air, stable and farm road dust and farm soil samples from two pig and cattle farms in the South Moravian Region. Volatile fatty acids (acetic, propanoic, butanoic and pentanoic) and their esters dominated along with aldehydes (butanal, pentanal and hexanal) and 4-methylphenol in the indoor and outdoor air samples. Road dust and soil samples contained mainly volatile aromatic compounds (toluene, benzene, ethylbenzene, styrene and xylenes), aliphatic hydrocarbons (largely n-alkanes), dichloromethane and carbon disulphide.

The aim of this study was to report the detection of methicillin-resistant Staphylococcus aureus (MRSA) strains at a veterinary university goat breeding farm and their characteristics. A total of 278 samples collected from animals, milk, environment and farm personnel between June 2006 and March 2008 were examined. The identification of S. aureus isolates was performed by a species specific PCR assay. All detected isolates were tested for resistance to oxacillin and other antimicrobials by phenotypic methods and for the mecA gene by PCR method. Eight MRSA were detected in this study. Five of them originated from goat's milk and three were recovered from one human carrier of the farm personnel. All obtained MRSA isolates were clonally consistent and were characterized as: SCCmec type IV, spa type t064, seb positive and for genes encoding TSST-1, PVL and exfoliative toxins A and B negative.

Between 1982 and 1992, trends in farm structural change resumed patterns that had existed from the Great Depression to the 1970s. That is, farms became fewer and larger. By 1992, the number of American farms declined below two million for the first time since the Civil War. Also, the trend toward dualism noted in the 1970s is over, as the number of small farms again declined rapidly during the 1980s. The trend toward large-scale agriculture is most prominent in the most important agricultural counties

The paper focuses on costs and yields of sugar beet in the Czech Republic in the context of economic efficiency and competitiveness in the period 2007-2011. The results are based on a sample survey of product costs and yields of agricultural commodities which has been carried out annually by the Institute of Agricultural Economics and Information. The economic efficiency is evaluated using Data Envelopment Analysis method (DEA). The paper also presents international comparison of the cost structure of sugar beet growing based on Agri benchmark Cash Crop network. Based on that, cost and revenues for the individual crops on \"typical farms\" are calculated for the various locations. The results show decreasing average cost per tonne of root, especially staff costs, and increasing profitability of Czech sugar beet producers between 2007 and 2011. Most producers are highly economically effective. However, there is potential in efficiency of material costs and sugar yields. Sugar beet seems to maintain its irreplaceable position in the Czech agriculture.

Con el objetivo de entender el comportamiento del conocimiento como parte de los factores de producción y competitividad del sector ovino caprino, desde el punto de vista epistemológico se estudiaron algunas fuentes de conocimiento tácito (la imaginación, un familiar, la propia experiencia, entre otras) y explícito (las estadísticas, un investigador, las normas), en 66 granjas ovino caprinas en Colombia durante cinco años, de 2007 a 2012. En el transcurso del proceso se evaluó el efecto que tuvieron en ellas dos sistemas de gestión: el primero correspondió a un sistema de asistencia técnica “tradicional”, con análisis y recomendaciones directas del profesional al productor, y en el segundo se trabajó con asistencia basada en creación y evolución del conocimiento, según los planteamientos de la gestión del conocimiento. Los datos se examinaron mediante pruebas de Kruskal-Wallis y Chi², y análisis de clúster y de correspondencia multivariado. Se encontró que, al tomar una decisión, las granjas tienden a privilegiar las fuentes de conocimiento tácito sobre las correspondientes al explícito. La aplicación de asistencia técnica clásica con recomendaciones directas no generó diferencias en las fuentes de conocimiento explícito (p>0,05), ni en aquellas de conocimiento tácito (p>0,05). De igual forma, las granjas intervenidas con gestión del conocimiento no presentaron diferencias en las fuentes de conocimiento tácito (p>0,05),ni en las de conocimiento explícito (p>0,05). Independientemente del sistema de gestión que se utilizó, las granjas mantuvieron su predilección por las fuentes de conocimiento tácito.