scholarly journals LA35 Poultry Fecal Marker Persistence Is Correlated with That of Indicators and Pathogens in Environmental Waters

2015 ◽  
Vol 81 (14) ◽  
pp. 4616-4625 ◽  
Author(s):  
Bina Nayak ◽  
Jennifer Weidhaas ◽  
Valerie J. Harwood
Keyword(s):  
Water Quality ◽  
Health Risk ◽  
Water Column ◽  
Poultry Litter ◽  
Land Application ◽  
Gene Marker ◽  
Rrna Gene ◽  
Content Type ◽  
The Impact ◽  
Over Time

ABSTRACTDisposal of fecally contaminated poultry litter by land application can deliver pathogens and fecal indicator bacteria (FIB) into receiving waters via runoff. While water quality is regulated by FIB enumeration, FIB testing provides inadequate information about contamination source and health risk. This microbial source tracking (MST) study compared the persistence of theBrevibacteriumsp. strain LA35 16S rRNA gene (marker) for poultry litter with that of pathogens and FIB under outdoor, environmentally relevant conditions in freshwater, marine water, and sediments over 7 days.Salmonella enterica,Campylobacter jejuni,Campylobacter coli,Bacteroidales, and LA35 were enumerated by quantitative PCR (qPCR), andEnterococcusspp. andE. coliwere quantified by culture and qPCR. Unlike the other bacteria,C. jejuniwas not detectable after 48 h. Bacterial levels in the water column consistently declined over time and were highly correlated among species. Survival in sediments ranged from a slow decrease over time to growth, particularly in marine microcosms and forBacteroidales. S. entericaalso grew in marine sediments. Linear decay rates in water (k) ranged from −0.17 day−1for LA35 to −3.12 day−1forC. coli. LA35 levels correlated well with those of other bacteria in the water column but not in sediments. These observations suggest that, particularly in the water column, the fate of LA35 in aquatic environments is similar to that of FIB,C. coli, andSalmonella, supporting the hypothesis that the LA35 marker gene can be a useful tool for evaluating the impact of poultry litter on water quality and human health risk.

scholarly journals Correlation of Quantitative PCR for a Poultry-SpecificBrevibacteriumMarker Gene with Bacterial and Chemical Indicators of Water Pollution in a Watershed Impacted by Land Application of Poultry Litter

2011 ◽  
Vol 77 (6) ◽  
pp. 2094-2102 ◽  
Author(s):  
Jennifer L. Weidhaas ◽  
Tamzen W. Macbeth ◽  
Roger L. Olsen ◽  
Valerie J. Harwood
Keyword(s):  
Quantitative Pcr ◽  
Environmental Samples ◽  
Marker Gene ◽  
Poultry Litter ◽  
Land Application ◽  
Fecal Pollution ◽  
Health Concern ◽  
Rrna Gene ◽  
Fecal Indicator ◽  
The Impact

ABSTRACTThe impact of fecal contamination from human and agricultural animal waste on water quality is a major public health concern. Identification of the dominant source(s) of fecal pollution in a watershed is necessary for assessing the safety of recreational water and protecting water resources. A field study was conducted using quantitative PCR (qPCR) for the 16S rRNA gene ofBrevibacteriumsp. LA35 to track feces-contaminated poultry litter in environmental samples. Based on sensitivity and specificity characteristics of the qPCR method, the Bayesian conditional probability that detection of the LA35 marker gene in a water sample represented a true-positive result was 93%. The marker's covariance with fecal indicator bacteria (FIB) and metals associated with poultry litter was also assessed in litter, runoff, surface water, and groundwater samples. LA35 was detected in water and soil samples collected throughout the watershed, and its concentration covaried with concentrations ofEscherichia coli, enterococci, As, Cu, P, and Zn. Significantly greater concentrations of FIB, As, Cu, P, and Zn were observed in edge-of-field runoff samples in which LA35 was detected, compared to samples in which it was not detected. Furthermore, As, Cu, P, and Zn concentrations covaried in environmental samples in which LA35 was detected and typically did not in samples in which the marker gene was not detected. The covariance of the poultry-specific LA35 marker gene with these known contaminants from poultry feces provides further evidence that it is a useful tool for assessing the impact of poultry-derived fecal pollution in environmental waters.

scholarly journals Consumption of Lysozyme-Rich Milk Can Alter Microbial Fecal Populations

2012 ◽  
Vol 78 (17) ◽  
pp. 6153-6160 ◽  
Author(s):  
Elizabeth A. Maga ◽  
Prerak T. Desai ◽  
Bart C. Weimer ◽  
Nguyet Dao ◽  
Dietmar Kültz ◽  
...  
Keyword(s):  
Human Milk ◽  
Gut Microbiome ◽  
16S Rrna Gene Sequencing ◽  
Fecal Microbiota ◽  
Rrna Gene ◽  
Gut Health ◽  
Content Type ◽  
Microbiome Composition ◽  
The Impact ◽  
Over Time

ABSTRACTHuman milk contains antimicrobial factors such as lysozyme and lactoferrin that are thought to contribute to the development of an intestinal microbiota beneficial to host health. However, these factors are lacking in the milk of dairy animals. Here we report the establishment of an animal model to allow the dissection of the role of milk components in gut microbiota modulation and subsequent changes in overall and intestinal health. Using milk from transgenic goats expressing human lysozyme at 68%, the level found in human milk and young pigs as feeding subjects, the fecal microbiota was analyzed over time using 16S rRNA gene sequencing and the G2 Phylochip. The two methods yielded similar results, with the G2 Phylochip giving more comprehensive information by detecting more OTUs. Total community populations remained similar within the feeding groups, and community member diversity was changed significantly upon consumption of lysozyme milk. Levels ofFirmicutes(Clostridia) declined whereas those ofBacteroidetesincreased over time in response to the consumption of lysozyme-rich milk. The proportions of these major phyla were significantly different (P< 0.05) from the proportions seen with control-fed animals after 14 days of feeding. Within phyla, the abundance of bacteria associated with gut health (BifidobacteriaceaeandLactobacillaceae) increased and the abundance of those associated with disease (Mycobacteriaceae,Streptococcaceae,Campylobacterales) decreased with consumption of lysozyme milk. This study demonstrated that a single component of the diet with bioactivity changed the gut microbiome composition. Additionally, this model enabled the direct examination of the impact of lysozyme on beneficial microbe enrichment versus detrimental microbe reduction in the gut microbiome community.

scholarly journals Influence of Fishmeal-Free Diets on Microbial Communities in Atlantic Salmon (Salmo salar) Recirculation Aquaculture Systems

2016 ◽  
Vol 82 (15) ◽  
pp. 4470-4481 ◽  
Author(s):  
Victor Schmidt ◽  
Linda Amaral-Zettler ◽  
John Davidson ◽  
Steven Summerfelt ◽  
Christopher Good
Keyword(s):  
Water Quality ◽  
Atlantic Salmon ◽  
Microbial Communities ◽  
Salmo Salar ◽  
Rrna Gene ◽  
Fish Diet ◽  
Content Type ◽  
Recirculating Aquaculture Systems ◽  
Alternative Feeds ◽  
The Impact

ABSTRACTReliance on fishmeal as a primary protein source is among the chief economic and environmental concerns in aquaculture today. Fishmeal-based feeds often require harvest from wild fish stocks, placing pressure on natural ecosystems and causing price instability. Alternative diet formulations without the use of fishmeal provide a potential solution to this challenge. Although the impact of alternative diets on fish performance, intestinal inflammation, palatability, and gut microbiota has been a topic of recent interest, less is known about how alternative feeds impact the aquaculture environment as a whole. The recent focus on recirculating aquaculture systems (RAS) and the closed-containment approach to raising food fish highlights the need to maintain stable environmental and microbiological conditions within a farm environment. Microbial stability in RAS biofilters is particularly important, given its role in nutrient processing and water quality in these closed systems. If and how the impacts of alternative feeds on microbial communities in fish translate into changes to the biofilters are not known. We tested the influence of a fishmeal-free diet on the microbial communities in RAS water, biofilters, and salmon microbiomes using high-throughput 16S rRNA gene V6 hypervariable region amplicon sequencing. We grew Atlantic salmon (Salmo salar) to market size in six replicate RAS tanks, three with traditional fishmeal diets and three with alternative-protein, fishmeal-free diets. We sampled intestines and gills from market-ready adult fish, water, and biofilter medium in each corresponding RAS unit. Our results provide data on how fish diet influences the RAS environment and corroborate previous findings that diet has a clear influence on the microbiome structure of the salmon intestine, particularly within the orderLactobacillales(lactic acid bacteria). We conclude that the strong stability of taxa likely involved in water quality processing regardless of diet (e.g.,Nitrospira) may further alleviate concerns regarding the use of alternative feeds in RAS operations.IMPORTANCEThe growth of the aquaculture industry has outpaced terrestrial livestock production and wild-capture fisheries for over 2 decades, currently producing nearly 50% of all seafood consumed globally. As wild-capture fisheries continue to decline, aquaculture's role in food production will grow, and it will produce an estimated 62% of all seafood consumed in 2020. A significant environmental concern of the industry is the reliance on fishmeal as a primary feed ingredient, as its production still requires harvest from wild fisheries. Our study adds to the growing body of literature on the feasibility of alternative, fishmeal-free diets. Specifically, we asked how fishmeal-free diets influence microbial communities in recirculating salmon farms. Unlike previous studies, we extended our investigation beyond the microbiome of the fish itself and asked how alterative diets influence microbial communities in water and critical biofilter habitats. We found no evidence for adverse effects of alternative diets on any microbial habitat within the farm.

scholarly journals Firm’s strategic choices and network knowledge dynamics: how do they affect innovation?

2018 ◽  
Vol 22 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Jose Antonio Belso-Martinez ◽  
Isabel Diez-Vial
Keyword(s):  
Absorptive Capacity ◽  
Knowledge Networks ◽  
Knowledge Network ◽  
Strategic Choices ◽  
Network Growth ◽  
Content Type ◽  
Endogenous Factors ◽  
The Impact ◽  
Innovative Capacity ◽  
Over Time

Purpose This paper aims to explain how the evolution of knowledge networks and firms’ strategic choices affect innovation. Endogenous factors associated with a path-dependent evolution of the knowledge network are jointly considered with a firm’s development of international relationships and increasing internal absorptive capacity over time. Design/methodology/approach In a biotech cluster, the authors gathered data on the firms’ characteristics and network relationships by asking about the technological knowledge they received in the cluster in 2007 and 2012 – “roster-recall” method. Estimation results were obtained using moderated regression analysis. Findings Firms that increase their involvement in knowledge networks over time also tend to increase their innovative capacity. However, efforts devoted to building international links or absorptive capacity negatively moderate the impact of network growth on innovation. Practical implications Practitioners have two alternative ways of increasing innovation inside knowledge networks: they can increase their centrality by developing their knowledge network interactions or invest in developing their internal absorptive capacity and new international sources of knowledge. Investing in both of these simultaneously does not seem to improve a firm’s innovative capacity. Originality/value Coupling firms’ strategic options with knowledge network dynamics provide a more complete way of explaining how firms can improve their innovative capacity.

scholarly journals Differences in the Rumen Methanogen Populations of Lactating Jersey and Holstein Dairy Cows under the Same Diet Regimen

2011 ◽  
Vol 77 (16) ◽  
pp. 5682-5687 ◽  
Author(s):  
Erin E. King ◽  
Rachel P. Smith ◽  
Benoit St-Pierre ◽  
André-Denis G. Wright
Keyword(s):  
Methanogenic Archaea ◽  
Milk Composition ◽  
Species Level ◽  
Rrna Gene ◽  
Content Type ◽  
Sequence Identity ◽  
Diet Regimen ◽  
Pcr Products ◽  
The Impact ◽  
Rumen Methanogen

ABSTRACTIn the dairy cattle industry, Holstein and Jersey are the breeds most commonly used for production. They differ in performance by various traits, such as body size, milk production, and milk composition. With increased concerns about the impact of agriculture on climate change, potential differences in other traits, such as methane emission, also need to be characterized further. Since methane is produced in the rumen by methanogenic archaea, we investigated whether the population structure of methanogen communities would differ between Holsteins and Jerseys. Breed-specific rumen methanogen 16S rRNA gene clone libraries were constructed from pooled PCR products obtained from lactating Holstein and Jersey cows, generating 180 and 185 clones, respectively. The combined 365 sequences were assigned to 55 species-level operational taxonomic units (OTUs). Twenty OTUs, representing 85% of the combined library sequences, were common to both breeds, while 23 OTUs (36 sequences) were found only in the Holstein library and 12 OTUs (18 sequences) were found only in the Jersey library, highlighting increased diversity in the Holstein library. Other differences included the observation that sequences with species-like sequence identity toMethanobrevibacter milleraewere represented more highly in the Jersey breed, whileMethanosphaera-related sequences and novel uncultured methanogen clones were more frequent in the Holstein library. In contrast, OTU sequences with species-level sequence identity toMethanobrevibacter ruminantiumwere represented similarly in both libraries. Since the sampled animals were from a single herd consisting of two breeds which were fed the same diet and maintained under the same environmental conditions, the differences we observed may be due to differences in host breed genetics.

The dynamics of regional and global expansion

2015 ◽  
Vol 23 (4) ◽  
pp. 306-327 ◽  
Author(s):  
Christian Geisler Asmussen ◽  
Bo Bernhard Nielsen ◽  
Tom Osegowitsch ◽  
Andre Sammartino
Keyword(s):  
Design Methodology ◽  
Global Market ◽  
Market Penetration ◽  
Content Type ◽  
Global Expansion ◽  
Rates Of Change ◽  
Global Space ◽  
The Impact ◽  
The Relationship ◽  
Over Time

Purpose – The purpose of this paper is to model and test the dynamics of home-regional and global penetration by multi-national enterprises (MNEs). Design/methodology/approach – Drawing on international business (IB) theory, the authors model MNEs adjusting their home-regional and global market presence over time. The authors test the resulting hypotheses using sales data from a sample of 220 of the world’s largest MNEs over the period 1995-2005. The authors focus specifically on the relationship between levels of market penetration inside and outside the home region and rates of change in each domain. Findings – The authors demonstrate that MNEs do penetrate both home-regional and global markets, often simultaneously, and that penetration levels often oscillate within an MNE over time. The authors show firms’ rates of regional and global expansion to be affected by their existing regional and global penetration, as well as their interplay. Finally, the authors identify differences in the steady states at which firms stabilize their penetration levels in the home-regional and the global space. The findings broadly confirm the MNE as an interdependent portfolio with important regional demarcations. Originality/value – The authors identify complex interdependencies between home-regional and global penetration and growth, paving the way for further studies of the impact of regions on MNE expansion.

The impact of investment on drinking water quality in rural China

2017 ◽  
Vol 9 (2) ◽  
pp. 255-269
Author(s):  
Ai Yue ◽  
Yaojiang Shi ◽  
Renfu Luo ◽  
Linxiu Zhang ◽  
Natalie Johnson ◽  
...  
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Rural Areas ◽  
Tap Water ◽  
Rural China ◽  
Ordinary Least Squares ◽  
Content Type ◽  
Representative Data ◽  
Nationally Representative ◽  
The Impact

Purpose Although access to safe drinking water is one of the most important health-related infrastructure programs in the world, drinking water remains a large problem in China today, especially in rural areas. Despite increased government investment in water resource protection and management, there is still an absence of academic studies that are able to document what path the investment has taken and whether it has had any tangible impact. The purpose of this paper is to analyze the impact of drinking water investment on drinking water in China. Design/methodology/approach The authors make use of nationally representative data from 2005 and 2012 to measure the impact of drinking water investment among 2,028 rural households in 101 villages across five provinces. Both ordinary least squares regression and probit regression are used to analyze the correlates and the impact of drinking water investment. Findings The authors demonstrate that water quality was likely a significant problem in 2004 but that China’s investment into drinking water appears to have resulted in initial improvements during the study period. The authors show that the most significant change came about in terms of hardware: villages that received more drinking water investment now have more piped tap water and more access to water treatment infrastructure (disinfecting and filtering facilities). High rates of rural resident satisfaction with drinking water suggest the effects of drinking water investment are being felt at the village level. Originality/value To the authors’ knowledge, this is the first empirical study on drinking water investment over time in rural China using nationally representative data.

Three stages of entrepreneurial orientation: the founder’s role

2019 ◽  
Vol 26 (2) ◽  
pp. 285-306 ◽  
Author(s):  
Torbjörn Ljungkvist ◽  
Börje Boers ◽  
Joachim Samuelsson
Keyword(s):  
Entrepreneurial Orientation ◽  
Single Case ◽  
Annual Reports ◽  
Structured Interviews ◽  
Theoretical Understanding ◽  
Content Type ◽  
Five Dimensions ◽  
The Impact ◽  
Over Time

Purpose The purpose of this paper is to understand the development of the five dimensions of entrepreneurial orientation (EO) over time by taking a founder’s perspective. Design/methodology/approach The paper draws on an in-depth single-case study. It combines semi-structured interviews in the company with archival data, such as annual reports, press clips and interviews in business magazines. Findings The results indicate that the EO dimensions change from being personalized and directly solution-oriented to being intangible value-creation-oriented. Originality/value By suggesting ownership-based EO configurations, this study contributes insights into how different ownership forms propel EO. These configurations – that is, personal, administrative based and intangible focused – show the impact of the EO dimensions and provide a systematic and theoretical understanding of EO change over time.

Brand awareness: revisiting an old metric for a new world

2017 ◽  
Vol 26 (5) ◽  
pp. 469-476 ◽  
Author(s):  
Jenni Romaniuk ◽  
Samuel Wight ◽  
Margaret Faulkner
Keyword(s):  
Market Share ◽  
Brand Management ◽  
Brand Awareness ◽  
Underlying Structure ◽  
Cross Sectional ◽  
Content Type ◽  
Country Level ◽  
Global Brand ◽  
The Impact ◽  
Over Time

Purpose Brand awareness is a pivotal, but often neglected, aspect of consumer-based brand equity. This paper revisits brand awareness measures in the context of global brand management. Design/methodology/approach Drawing on the method of Laurent et al. (1995), this cross-sectional longitudinal study examines changes in brand awareness over time, with sample sizes of approximately 300 whisky consumers per wave in three countries: United Kingdom, Taiwan and Greece. Findings There is consistency in the underlying structure of awareness scores across countries, and over time, extending the work of Laurent et al. (1995). Results show that a relevant operationalisation of brand awareness needs to account for the history of the brand. Furthermore, the nature of the variation of brand awareness over time interacts with a brand’s market share. Research limitations/implications When modelling the impact of brand awareness researchers need to consider two factors – the brand’s market share and whether a more stable or volatile measure is sought. This avoids mis-specifying the country-level contribution of brand awareness. Practical implications Global brand managers should be wary of adopting a “one size fits all” approach. The choice of brand awareness measure depends on the brand’s market share, and the desire for higher sensitivity or stability. Originality/value The paper provides one of the few multi-country investigations into brand awareness that can help inform global brand management.

Rebuilding Nepal: traditional and modern approaches, building or diminishing resilience?

2018 ◽  
Vol 9 (3) ◽  
pp. 218-229 ◽  
Author(s):  
Catherine Forbes
Keyword(s):  
Building Materials ◽  
Local Community ◽  
Vernacular Architecture ◽  
Research Approach ◽  
Content Type ◽  
Knowledge And Skills ◽  
Masonry Construction ◽  
Action Research Approach ◽  
The Impact ◽  
Over Time

Purpose The purpose of this paper is to highlight the importance of vernacular architecture and traditional knowledge to building resilience in Nepal and the impact of modernisation on that resilience and architectural diversity. Design/methodology/approach Using an action research approach, including field observations and discussions with local community members, artisans, architects, engineers and other international experts, the study examines the resilience of traditional building typologies to natural hazards in Nepal, including earthquake; the changes that have occurred over time leading to the failure and/or rejection of traditional construction; and a review of post-earthquake reconstruction options, both traditional and modern. Findings Although traditional approaches have been cyclically tested over time, this study found that changes in building materials, technologies, knowledge and skills, access to resources, maintenance practices, urban environments and societal aspirations have all contributed to the popular rejection of vernacular architecture following the earthquakes. Research limitations/implications The research is limited to traditional timber and masonry construction in the Kathmandu Valley and surrounding mountain areas. Practical implications To improve resilience the study identifies the need for capacity building in both traditional and modern construction technologies; adoption of approaches that use local materials, knowledge and skills, whilst addressing local timber shortages and access issues; a transparent construction certification system; good drainage; and regular maintenance. Originality/value The study critically evaluates the impact of technological, environmental, social and economic changes over time on the resilience of vernacular housing in Nepal.

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