Modelling Crustacean Fisheries: Effects of Parasites on Management Strategies

1992 ◽  
Vol 49 (2) ◽  
pp. 327-336 ◽  
Author(s):  
Armand M. Kuris ◽  
Kevin D. Lafferty
Keyword(s):  
Mathematical Models ◽  
Spatial Scale ◽  
Reproductive Performance ◽  
Management Practices ◽  
Management Strategies ◽  
Larval Recruitment ◽  
Commercially Important ◽  
The Common ◽  
The Impact ◽  
Crustacean Fisheries

The reproductive performance of commercially important crustaceans may be considerably affected by symbiotic nemertean egg predators and parasitic castrators. Because these parasites commonly affect only females or feminize males, they may be protected by management practices that protect females. To manage a parasitized stock, we suggest that strategies should vary depending on the recruitment dynamics of both host and parasite. For a certain spatial scale, recruitment to a population may be "open" or "closed" depending on the behavior of planktonic larvae, the duration of these planktonic stages, and the flush rate of the environment of the adult host. Both hosts and parasites may have open or closed larval recruitment. We developed mathematical models to investigate the impact of protection of females on a hypothetical fishery for different combinations of host and parasite recruitment dynamics. The models suggest that the common practice of releasing females is not advantageous when a fishery is affected by a parasite. Retaining females in the catch is preferable in most cases. Treating or culling infected females may be advisable when host recruitment is closed.

scholarly journals Rural Roads Are Paving the Way for Land-Use Intensification in the Uplands of Laos

Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 330
Author(s):  
Jean-Christophe Castella ◽  
Sonnasack Phaipasith
Keyword(s):  
Land Use ◽  
Management Practices ◽  
Management Strategies ◽  
Farming Systems ◽  
Long Term Effects ◽  
Group Discussions ◽  
Rural Roads ◽  
External Resources ◽  
Hybrid Maize ◽  
The Impact

Road expansion has played a prominent role in the agrarian transition that marked the integration of swidden-based farming systems into the market economy in Southeast Asia. Rural roads deeply altered the landscape and livelihood structures by allowing the penetration of boom crops such as hybrid maize in remote territories. In this article, we investigate the impact of rural road developments on livelihoods in northern Laos through a longitudinal study conducted over a period of 15 years in a forest frontier. We studied adaptive management strategies of local stakeholders through the combination of individual surveys, focus group discussions, participatory mapping and remote-sensing approaches. The study revealed the short-term benefits of the maize feeder roads on poverty alleviation and rural development, but also the negative long-term effects on agroecosystem health and agricultural productivity related to unsustainable land use. Lessons learnt about the mechanisms of agricultural intensification helped understanding the constraints faced by external interventions promoting sustainable land management practices. When negotiated by local communities for their own interest, roads may provide livelihood-enhancing opportunities through access to external resources, rather than undermining them.

scholarly journals Exploring the impact of a decision support algorithm to improve clinicians’ chemotherapy-induced peripheral neuropathy assessment and management practices: a two-phase, longitudinal study

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Robert Knoerl ◽  
Emanuele Mazzola ◽  
Fangxin Hong ◽  
Elahe Salehi ◽  
Nadine McCleary ◽  
...  
Keyword(s):  
Decision Support ◽  
Peripheral Neuropathy ◽  
Management Practices ◽  
Management Strategies ◽  
Clinic Visit ◽  
Evidence Based ◽  
Two Phase ◽  
Assessment Index ◽  
Patient Reported ◽  
The Impact

Abstract Background Chemotherapy-induced peripheral neuropathy (CIPN) negatively affects physical function and chemotherapy dosing, yet, clinicians infrequently document CIPN assessment and/or adhere to evidence-based CIPN management in practice. The primary aims of this two-phase, pre-posttest study were to explore the impact of a CIPN clinician decision support algorithm on clinicians’ frequency of CIPN assessment documentation and adherence to evidence-based management. Methods One hundred sixty-two patients receiving neurotoxic chemotherapy (e.g., taxanes, platinums, or bortezomib) answered patient-reported outcome measures on CIPN severity and interference prior to three clinic visits at breast, gastrointestinal, or multiple myeloma outpatient clinics (n = 81 usual care phase [UCP], n = 81 algorithm phase [AP]). During the AP, study staff delivered a copy of the CIPN assessment and management algorithm to clinicians (N = 53) prior to each clinic visit. Changes in clinicians’ CIPN assessment documentation (i.e., index of numbness, tingling, and/or CIPN pain documentation) and adherence to evidence-based management at the third clinic visit were compared between the AP and UCP using Pearson’s chi-squared test. Results Clinicians’ frequency of adherence to evidence-based CIPN management was higher in the AP (29/52 [56%]) than the UCP (20/46 [43%]), but the change was not statistically significant (p = 0.31). There were no improvements in clinicians’ CIPN assessment frequency during the AP (assessment index = 0.5440) in comparison to during the UCP (assessment index = 0.6468). Conclusions Implementation of a clinician-decision support algorithm did not significantly improve clinicians’ CIPN assessment documentation or adherence to evidence-based management. Further research is needed to develop theory-based implementation interventions to bolster the frequency of CIPN assessment and use of evidence-based management strategies in practice. Trial registration ClinicalTrials.Gov, NCT03514680. Registered 21 April 2018.

Covid-19 Crisis Management Responses of Small Tourism Firms in South Africa

2022 ◽  
Author(s):  
Irma Booyens ◽  
Christian M. Rogerson ◽  
Jayne M. Rogerson ◽  
Tom Baum
Keyword(s):  
South Africa ◽  
Crisis Management ◽  
Management Practices ◽  
Management Strategies ◽  
Tourism Industry ◽  
Government Support ◽  
Interview Survey ◽  
Tourism Enterprises ◽  
And Coping ◽  
The Impact

Although the literature on COVID-19 is expanding, particularly in relation to crisis management responses pursued by large tourism enterprises, currently few studies exist on the responses of small tourism firms and more specifically of the crisis management practices of small and microaccom modation establishments. The aim in this study is to investigate the business management responses of small tourism firms to the COVID-19 pandemic crisis and restrictions in South Africa. Themes of concern are whether enterprises have been able to sustain operations and adopt certain coping mechanisms or management strategies to mitigate the pandemic’s impact. The article reports on an interview survey of small and microenterprises engaged in accommodation services (N = 75) in South Africa under lockdown restrictions as a means of assessing the responses and coping strategies during an unprecedented crisis of this core component of the country’s tourism industry. Among key findings are that small and microlodging firms that have suffered severe financial losses because of the COVID-19 shock have few viable mechanisms to cope with the impact of the crisis and that government support to aid recovery has been insufficient in South Africa. This research contributes to the limited body of international scholarship that examines how small and microaccommodation firms, a major group and contributor of many economies, are navigating the unprecedented COVID-19 environment.

scholarly journals Meta-Analysis of Strategies to Reduce NH3 Emissions from Slurries in European Agriculture and Consequences for Greenhouse Gas Emissions

Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1633
Author(s):  
Christoph Emmerling ◽  
Andreas Krein ◽  
Jürgen Junk
Keyword(s):  
Carbon Dioxide ◽  
Nitrous Oxide ◽  
Greenhouse Gases ◽  
Greenhouse Gas ◽  
Management Practices ◽  
Meta Analysis ◽  
Management Strategies ◽  
Ammonia Emission ◽  
Ammonia Emissions ◽  
The Impact

The intensification of livestock production, to accommodate rising human population, has led to a higher emission of ammonia into the environment. For the reduction of ammonia emissions, different management steps have been reported in most EU countries. Some authors, however, have criticized such individual measures, because attempts to abate the emission of ammonia may lead to significant increases in either methane, nitrous oxide, or carbon dioxide. In this study, we carried out a meta-analysis of experimental European data published in peer-reviewed journals to evaluate the impact of major agricultural management practices on ammonia emissions, including the pollution swapping effect. The result of our meta-analysis showed that for the treatment, storage, and application stages, only slurry acidification was effective for the reduction of ammonia emissions (−69%), and had no pollution swapping effect with other greenhouse gases, like nitrous oxide (−21%), methane (−86%), and carbon dioxide (−15%). All other management strategies, like biological treatment, separation strategies, different storage types, the concealing of the liquid slurry with different materials, and variable field applications were effective to varying degrees for the abatement of ammonia emission, but also resulted in the increased emission of at least one other greenhouse gas. The strategies focusing on the decrease of ammonia emissions neglected the consequences of the emissions of other greenhouse gases. We recommend a combination of treatment technologies, like acidification and soil incorporation, and/or embracing emerging technologies, such as microbial inhibitors and slow release fertilizers.

Productive and reproductive performance of crossbred and indigenous dairy cows at smallholdings in selected towns of Jimma Zone, Ethiopia

2021 ◽  
Vol 61 (1) ◽  
pp. 92
Author(s):  
Belay Duguma
Keyword(s):  
Dairy Cattle ◽  
Dairy Cows ◽  
Milk Yield ◽  
Reproductive Performance ◽  
Management Practices ◽  
Production Systems ◽  
Management Strategies ◽  
Factors Affecting ◽  
Jimma Zone ◽  
Improvement Programs

Context Evaluation of the performance of dairy cows kept in different production systems is essential for the development of appropriate breeding strategies. Aims To examine milk production and reproductive performance of crossbred (CB) and indigenous (I) dairy cows, farmers’ traits preference for CB and I breeding females, and factors affecting the performance of dairy cattle on smallholdings in selected towns of Jimma Zone, Ethiopia. Methods In total, 52 smallholder dairy cattle farmers were randomly sampled and data were collected through individual face-to-face interviews by using structured questionnaires. The traits studied were daily milk yield (DMY), lactation milk yield (LMY), lactation length (LL), age at first service (AFS), age at first calving (AFC), calving interval (CI), days open (DO), and number of service per conception (NSC), all being factors affecting performance of dairy cattle and farmers’ preferred dairy traits. Results On average, CB cows had significantly (P < 0.05) higher DMY (6.0 ± 0.33 vs 1.8 ± 0.07 L/cow), LMY (1466.7 ± 1.13 vs 376.0 ± 21.02 L (L)), LL (8.1 ± 0.41 vs 6.9 ± 0.22 months), and lower AFS (2.69 ± 0.1 vs 3.3 ± 0.07 years), AFC (3.7 ± 0.13 vs 4.3 ± 0.07 years) and CI (21.2 ± 1.37 vs 29.8 ± 1.30 months) than did I cows. However, DO and NSC were not significantly (P > 0.05) affected by genotype. In order of perceived importance, high milk yield (mean rank = 0.306), LL (0.292) and fertility (0.199) were farmers’ most preferred traits for CB breeding cows, and the corresponding preferred traits for I cows were high milk yield (0.253), adaptability (0.229) and LL (0.192). The most important factors perceived by farmers affecting the performance of dairy cattle were breed, nutrition, diseases, breeding and management practices Conclusions The findings of the study indicated that even though CB cows performed better, the performance of both breeds of dairy cows in the study area was found to be generally low due to delayed AFS, late AFC, long CI, shorter LL, low daily and LMY and high NSC. Implications The study highlighted that there is a potential for increasing the performance of dairy cows in the study area, through improved management strategies leading to shorter AFS, AFC, CI and lower NSC. Furthermore, future breed-improvement programs should take into consideration farmers’ trait preferences in design of sustainable improvement programs.

Understanding rider:horse bodyweight ratio trends, weight management practices and rider weight perceptions within leisure and amateur riders in the UK

2021 ◽  
pp. 1-16
Author(s):  
C.L. Challinor ◽  
H. Randle ◽  
J.M. Williams
Keyword(s):  
Weight Management ◽  
Online Survey ◽  
Management Practices ◽  
Management Strategies ◽  
Legal Responsibility ◽  
Estimation Methods ◽  
Social Licence To Operate ◽  
The Uk ◽  
Post Hoc ◽  
The Impact

Horse riders in the UK have a legal responsibility for the welfare of the horses in their care, outlined by the Animal Welfare Act (2006). Understanding weight management factors that influence rider: horse bodyweight (RHBW) ratio is key to safeguarding horse welfare as human obesity rates increase. Recent high-profile incidents have seen riders being asked to dismount for being too heavy, demonstrating an awareness of the possible impact of excessive rider weight, threatening the equestrian industry’s social licence to operate. This study investigated RHBW trends within the UK leisure and amateur rider population to understand rider perception of ‘ideal’ RHBW and factors influencing rider and horse weight management. An online survey (SurveyMonkey®) was distributed via UK equine-related Facebook™ groups and collected information on horse and rider demographics, rider weight management strategies and respondents’ views on the importance of rider weight on horse welfare. Kruskal-Wallis analyses with Mann Whitney U post-hoc tests identified whether differences in respondent views differed between RHBW groups. A total of 971 riders completed the survey; respondents were aged between 18-65+ years old and 88% (n=953) were experienced riders. RHBWs were calculated for 764 (79%) of respondents as 21.2% (n=206) did not know either their own and/or their horses’ weight. Weight tapes (44.5%; n=432) and weigh bridges (29.5%; n=286) were common horse weight estimation methods. RHBWs ranged from 4.9% to 21.88%, mean: 12.5%±2.7%. Riders with lower RHBW thought about their own weight less and measured their horses’ weight less often than those with higher ratios (P<0.005, P<0.0004, respectively). The majority of riders who participated were weight conscious and recognised potential detrimental impacts associated with increased rider weight. Development of RHBW guidelines supported by equestrian governing bodies would highlight the need for riders to consider the impact of weight and support them in choosing suitable horses.

Managing risk in mergers and acquisitions activity: beyond ‘good’ and ‘bad’ management

2015 ◽  
Vol 30 (2) ◽  
pp. 160-175 ◽  
Author(s):  
Alnoor Bhimani ◽  
Mthuli Ncube ◽  
Prabhu Sivabalan
Keyword(s):  
Risk Management ◽  
Management Practices ◽  
Global Financial Crisis ◽  
Management Strategies ◽  
Future Research ◽  
Agency Conflicts ◽  
Complex Behaviour ◽  
Content Type ◽  
The Global Financial Crisis ◽  
The Impact

Purpose – This paper aims to assess the impact of the presence/absence of risk management practices on the risk of merger and acquisition (M&A) failure. Design/methodology/approach – An agency theoretic perspective is adopted, along with a mixed-methods approach to study managerial complexity beyond simply “good” and “bad”. The focus is on an agency conflicts. Findings – The authors first present an integrated framework that classifies managerial behaviour and risk management, where M&A bids can become vehicles for maximising managerial benefits rather than shareholder value. The authors proceed to consider M&A activity that benefits both managers and shareholders in the presence of risk management strategies. Research limitations/implications – The paper highlights the benefits of multiple paradigms and research paths that address dimensions captured by an agency theoretic perspective. Practical implications – The authors regard this paper as having particular significance in that the global financial crisis has impacted M&A activities and objectives, shifting the employment and related risks faced by managers. Originality/value – The paper suggests future research paths to advance the understanding of the complex behaviour of managers involved in M&A activities that go beyond the classification of “good” and “bad” managers.

scholarly journals 203 Development and evaluation of a dynamic simulation model of farm management strategies affecting the reproductive performance of a suckled beef cow herd

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 32-32
Author(s):  
Richard Lynch ◽  
Paul Crosson ◽  
Alan Kelly ◽  
David Kenny
Keyword(s):  
Simulation Model ◽  
Dynamic Simulation ◽  
Reproductive Performance ◽  
Management Strategies ◽  
Farm Management ◽  
Beef Cow ◽  
Reproductive Management ◽  
Dynamic Simulation Model ◽  
Production Cycles ◽  
The Impact

Abstract Reproductive output in suckled beef cow systems is underpinned by a combination of genetics and the impact of efficient animal management strategies which given their cumulative nature, are difficult to evaluate. A dynamic simulation model (Grange Reproductive Management Model; GReMM) was developed replicating the reproductive performance of a suckled beef cow herd over multiple production cycles using the Stella Architect dynamic modelling platform (isee systems, Ventana, Lebanon, USA). Model inputs for farm parameters include dates and duration of breeding seasons in addition to nutrition and management of the periparturient beef cow. Specific management parameters pertaining to the duration of the postpartum anoestrus interval (PPAI), such as the body condition score of the cow at calving (BCSc), level of postpartum nutrition (PPN), management of the suckling calf and bio-stimulation of the dam pre-breeding are modelled. Outputs are displayed in the form of shifts in calving distribution, calving rates and calves per cow per year. Scenario analysis consisted of the implementation of a BASE scenario representative of current industry best practice (Normal reproductive management; NRM: BCSc, 2.75; PPN, 100 MJ ME/d; ad libitum suckling). Two further scenarios were developed representing a more intensively managed herd, with high levels of nutrition pre and post calving in addition to alternative reproductive management strategies (Intensive reproductive management; IRM), and a herd with a low level of nutritional management pre and postpartum (Poor reproductive management; PRM). Outputs generated in terms of calving distribution over six production cycles, indicated that a shift in the calving spread towards later in the calving season occurred in the PRM scenario, and a small improvement in reproductive efficiency evident in the IRM scenario over NRM. The model developed offers a decision support tool with the capability of evaluating practical on-farm management decisions on herd reproductive performance.

scholarly journals Plant Breeding and Management Strategies to Minimize the Impact of Water Scarcity and Biotic Stress in Cereal Crops under Mediterranean Conditions

Agronomy ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 75
Author(s):  
Néstor Pérez-Méndez ◽  
Cristina Miguel-Rojas ◽  
Jose Antonio Jimenez-Berni ◽  
David Gomez-Candon ◽  
Alejandro Pérez-de-Luque ◽  
...  
Keyword(s):  
Climate Change ◽  
Management Practices ◽  
Management Strategies ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Biotic And Abiotic Stress ◽  
Fungal Disease Resistance ◽  
New Varieties ◽  
Rice Water ◽  
The Impact

Wheat and rice are two main staple food crops that may suffer from yield losses due to drought episodes that are increasingly impacted by climate change, in addition to new epidemic outbreaks. Sustainable intensification of production will rely on several strategies, such as efficient use of water and variety improvement. This review updates the latest findings regarding complementary approaches in agronomy, genetics, and phenomics to cope with climate change challenges. The agronomic approach focuses on a case study examining alternative rice water management practices, with their impact on greenhouse gas emissions and biodiversity for ecosystem services. The genetic approach reviews in depth the latest technologies to achieve fungal disease resistance, as well as the use of landraces to increase the genetic diversity of new varieties. The phenomics approach explores recent advances in high-throughput remote sensing technologies useful in detecting both biotic and abiotic stress effects on breeding programs. The complementary nature of all these technologies indicates that only interdisciplinary work will ensure significant steps towards a more sustainable agriculture under future climate change scenarios.

scholarly journals Impacts of land management on the resilience of Mediterranean dry forests to fire

2016 ◽  
Author(s):  
Matteo Jucker Riva ◽  
Gudrun Schwilch ◽  
Hanspeter Liniger ◽  
Alejandro Valdecantos
Keyword(s):  
Land Management ◽  
Management Practices ◽  
Fire Regime ◽  
Management Strategies ◽  
Time Frame ◽  
Mediterranean Forests ◽  
Before And After ◽  
History Of ◽  
Time Specific ◽  
The Impact

Wildfires have always been a part of the history of Mediterranean forests. However, forest regeneration after a wildfire is not certain. It depends on many factors, some of which may be influenced by land management activities. Failure of regeneration will cause a regime shift in the ecosystem, reducing the provision of ecosystem services and ultimately leading to desertification. How can we increase Mediterranean forests&rsquo; resilience to fire? To answer this question, we did a literature review, investigating chains of processes that allow forests to regenerate (which we label &ldquo;regeneration mechanisms&rdquo;), and assessed the impact of selected management practices documented in the WOCAT database on the regeneration mechanisms. We identified three distinct regeneration mechanisms that enable Mediterranean forests to recover, as well as the time frame before and after a fire in which they are at work, and factors that can hinder or support resilience. The three regeneration mechanisms enabling a forest to regenerate after a fire consist of regeneration (1) from a seed bank; (2) from resprouting individuals; and (3) from unburned plants that escaped the fire. Management practices were grouped into four categories: (1) fuel breaks, (2) fuel management, (3) afforestation, and (4) mulching. We assessed how and under what conditions land management modifies the ecosystem&rsquo;s resilience. The results show that land management influences resilience by interacting with resilience mechanisms before and after the fire, and not just by modifying the fire regime. Our analysis demonstrates a need for adaptive &ndash; i.e. context- and time-specific &ndash; management strategies.

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