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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Nutrient Utilization, Lactational Performance, and Profitability of Dairy Cows by Feeding Protein Supplements in High-Forage Lactation Diets

Neal, Kathryn 01 May 2014 (has links)
Due to the increasing cost of soybean meal and concerns of excess N being excreted into the environment, new protein supplements have been developed. Two products that have shown potential in increasing N utilization efficiency are slow release urea (SRU; Optigen) and ruminal escape protein derived from yeast (YMP; DEMP). The objective of this study was to assess the effects of feeding these 2 supplements in high-forage [(54% of total dietary dry matter (DM)] dairy diets on nutrient utilization, feed efficiency, lactational performance of dairy cows, and their impacts on income-over feed costs. Twelve multiparous dairy cows were used in a triple 4 × 4 Latin square design with one square consisting of ruminally cannulated cows. Treatments included: 1) control, 2) SRU-supplemented total mixed ration (TMR, SRUT), 3) YMP-supplemented TMR (YMPT), and 4) SRU and YMP-supplemented TMR (SYT). The control consisted only of a mixture of soybean meal and canola meal (SBMCM) in a 50:50 ratio. The SRU and the YMP were supplemented at 0.49% and 1.15% DM, respectively. The experiment consisted of 4 periods lasting 28 d each (21 d of adaptation and 7 d of sampling). Cows fed YMPT and SYT had decreased intake of DM, and all supplemented treatments had lower crude protein intake compared to those fed the control. Milk yield tended to have the greatest increase in YMPT compared with the control (41.1 vs. 39.7 kg/d) as well as a tendency for increased milk fat and protein yields. Feed efficiencies based on yields of milk, 3.5% fat-corrected milk, and energy-corrected milk increased at 10-16% due to protein supplementation. Cows fed with protein supplements partitioned less energy toward body weight gain, but tended to partition more energy toward milk production. Efficiency of use of feed N to milk N increased by feeding SRUT and YMPT, and milk N-to-manure N ratio increased in YMPT. Cows fed SRUT or YMPT tended to improve income-over feed costs. Overall results from this experiment indicate that replacing SBMCM with SRU and YMP in high-forage dairy diets can be a good approach to enhance dairy profitability through improved nutrient utilization efficiencies by lactating dairy cows.
192

Financial management and profitability of small and medium enterprises

Nguyen, Kieu Minh Unknown Date (has links)
After a decade of reforming policy, building and developing the multi-sector market economy, Small and Medium Enterprises (SMEs) in Vietnam have developed strongly and contributed to creating employment, increasing GDP, and raising the nation’s volume of exports. However, SMEs have found difficulties on the way to development due to lack of management experience and financial resources, and due to uncertainty within the business environment. As a result, SMEs often faced obstacles during their operations. This thesis examines the relationship between financial management and profitability of SMEs to determine whether financial management practices and financial characteristics impact on SME profitability. Objectives of the thesis are (1) to investigate and describe features of financial management practices and financial characteristics of SMEs in Vietnam, (2) to develop and test a model of SME profitability, and (3) to contribute knowledge of the relationships between financial management and characteristics to improve SME profitability by using tools of efficient financial management. In terms of structure, the thesis has six chapters. The thesis begins by defining the research problem and questions, and providing a justification for the research study. Chapter one also reviews the research background, and presents definitions of terms, significance and scope of the study. Chapter two examines the economic background, business structure and the development of SMEs in Vietnam. This chapter also reviews previous research related to financial management for SMEs in Vietnam to identify gaps between financial management for SMEs in Vietnam and financial management for SMEs worldwide. Chapter three reviews financial management including financial management practices, financial characteristics and profitability of SMEs around the world, especially in the developed economies such as the United States of America (USA), the United Kingdom (UK), Australia and Canada. This review emphasizes profitability and the impact of financial management practices and financial characteristics on SME profitability. Objectives of this chapter are to review previous research related to the areas of financial management practices, financial characteristics, and profitability of SMEs and to build a model of the impact of financial management practices and financial characteristics on SME profitability. Chapter four discusses aspects of the research methodology including research design, data collection and data analysis methods, and hypothesis testing to support the model. Objectives of this chapter are: (1) to justify the research methodology of this study, (2) to explain research methodology used in the study, and (3) to demonstrate how research design, and data collection and analysis can be utilized in this study to answer the research questions outlined in the chapter 1. Data analysis and findings are presented in chapter five. This chapter presents descriptive findings of financial management practices, financial characteristics and SME profitability and findings of the research study related to testing the model of SME profitability. Objectives of this chapter are (1) to systematically present the descriptive findings of the research study, (2) to interpret significance of these findings based on data analysis, (3) to present the results of testing the model of SME profitability, and (4) to explain how the model, developed from a literature review, was supported by data analysis. Finally, the thesis ends with chapter six where conclusions are summarized and applications of the research findings are indicated for the financial management practitioners. The thesis provides descriptive findings of financial management practices and financial characteristics and demonstrates the simultaneous impact of financial management practices and financial characteristics on SME profitability. In addition, the research study provides a model of SME profitability, in which profitability was found to be related to financial management practices and financial characteristics. With the exception of debt ratios, all other variables including current ratio, total asset turnover, working capital management and short-term planning practices, fixed asset management and long-term planning practices, and financial and accounting information systems were found to be significantly related to SME profitability. With the findings as presented above, this research study provides many implications for financial management practices and contributes to knowledge of financial management of SMEs. The model of SME profitability can be used as guidance for actions to improve the profitability of SMEs in Vietnam.
193

台灣網通業持續性競爭優勢之研究 / A study on the sustained competitive advantage of networking equipment industry

鄭吉利, Cheng, Chi Li Unknown Date (has links)
台灣今天所面對的國際競爭壓力與經營困境不是突然發生的,觀察台灣高科技產業獲利能力的持續下滑現象,企業經營者早就應該想到,台灣代工製造模式要如何繼續發展下去?透過對台灣網路通訊設備產業持續性競爭優勢之探討,分析企業的競爭策略,期望協助台灣廠商及投資大眾在對的時間做對的決定,讓台灣產業掌握提升價值及持續成長的契機,強化獨特的優勢與資源,增進國際競爭力。 學術上有許多篇論文探討網通產業競爭優勢,並建議很多的策略,網通業為了成長與獲利,必然採取類似的競爭策略,但近年來產業獲利結果卻呈現衰退,這是大部分台灣電子代工業的宿命嗎?是否台灣品牌廠商仍有持續的競爭優勢?本研究將依據相關理論,從獲利能力來看企業的績效變化,從競爭優勢來探討企業獨特能耐、資源與經營策略的差距,並從未來產業發展趨勢來看台灣企業應如何改變或加強策略,才能開創或持續其競爭優勢。 以台灣網通產業而言,品牌廠商過去的超額利潤,隨著經營環境的改變,成功要件不復存在,勢必調整商業獲利模式;而取得被重要供應鏈整合的代工業者,保有較低的代工利潤,加上深耕研發及製程技術,在市場需求增溫時,發揮規模經濟的低成本優勢,因此較具持續性競爭優勢。 依本研究發現即便網通業有機會創造出未來黃金十年,隨產品售價與獲利下滑後,台灣網通產業的淨獲利率只在3%至4%之間,建議各企業依據所處的競爭形勢,適度調整經營策略,方可提升或維持其競爭優勢。 / Observing the phenomenon of continuous declining profitability in Taiwan’s high-tech industry, enterprises in Taiwan should have long anticipated that functioning businesses nowadays face higher difficulties in sustaining international competitive advantage. How Taiwan’s Original Equipment Manufacturers (OEM) involves in development process should be taken into prior consideration. Analyzing the competitive strategy of Taiwan’s network communications equipment industry, not only allows the industry to strengthen its values and enhance the efficiency of interior resources; it can also help investors grasp the right timing in making investing decision. In order to gain profit and growth, most competitors in the industry chose to yield a similar operating strategy when confronting its rival. However, as the issue of deteriorating profitability rise to the surface, it is necessary to reconsider the options. Can major Taiwanese brand companies maintain its competitive advantage? Based on relevant theories, this research will evaluate alterations in business performance though profitability and estimate business competitiveness according to the difference in resources and operating strategies. In addition, this study will give suggestion on how to create or strengthen competitive advantage in perspective of future industrial trends. In the past, brand companies in the CNC industry had excessing profits. However, due to changes in business environment, the elements of past success no longer exist and companies are focus to adjust their profitability formula; the companies that were integrated into key supply chains are able to maintain low OEM margins, achieve economies of scale when market demand rises though their R&D bedrock and manufacturing technology. This study reveals that even the Network industry has the opportunity to create its golden years. Due to declining sale prices and profitability, Taiwan CNC industry's net profit is merely 3% to 4%, therefore companies are recommended to base on its current competitive position, moderately adjust its business strategy, to enhance or maintain their competitive advantage.
194

Dressed for Success : A study of Success Factors For Small and Medium-sized Manufacturing Enterprises in Sweden

Lingegård, Sofia, Sandström, Emma January 2008 (has links)
<p>The business climate of today, with increasing globalization, has resulted in structural changes in the commercial and industrial sectors. As a result, many large companies have moved their production abroad. Therefore the smaller companies have become increasingly important for growth and employment nationally. Small businesses are a significant contributor to the well-being of nations and small and medium-sized enterprises (SMEs) play an important role for Sweden, both in terms of economic contribution and employment.</p><p>Success has been discussed and investigated for a long period of time and the question is how it should be defined and measured. Many theories have been produced including different definitions and research methods. For this thesis, however, success is defined as the growth and financial performance of a firm measured in volume growth, relative change in net turnover, and value growth, relative change in equity. As a side condition, profit margins must be positive for a company to be classified as successful. This thesis hence aims to determine which factors influence the success of small and medium-sized enterprises in Sweden and how they influence the success of these enterprises.</p><p>Eleven manufacturing SMEs, seven successful and four unsuccessful, were investigated and analyzed separately and then compared with one another in an attempt to determine which specific factors contributed to their respective performance. The four unsuccessful companies were included in the investigation for comparison to be able to identify the specific factors for successful companies. The analyses resulted in the following areas: Organization, Vision and Strategy, Characteristics of the CEO, Core Competences, Recruiting, Product Development and Innovations and Market. Among these factors Vision and Strategy, Core Competences and Customer Interaction were identified as the factors that have the greatest impact on success. Additionally, two clear relations between factors could be determined, i.e. between Clear vision and strategy and Defined culture as well as a relation between Flexibility and Customer Interaction.</p><p>The conclusions are generalizable to all manufacturing SMEs in Sweden since the sample selection is representative for the target population. Furthermore, the success factors could be applied to companies abroad as well if the business climate and the conditions are similar. Whether the factors can be applied to firms that act within different SNI-codes (Swedish Standard Industrial Classification) besides manufacturing is yet to be proved.</p><p>For further research we suggest a deeper investigation, where the information is obtained from more than one sources within the company. Also, the external networks of the company could be of interest to interview. Other aspects to investigate further would be potential differences between small and medium-sized firms and whether or not the results are applicable for other industries.</p>
195

Styrning mot lönsamhet : ur ledningens perspektiv

Svensson, Jesper January 2008 (has links)
<p>Uppsatsens syfte avser att beskriva hur ACB Laminat, ur ledningens perspektiv, arbetar med lönsamhetsstyrning. Vidare ska eventuella brister i detta tillvägagångssätt belysas och analyseras, för att förslag till tänkbara åtgärder ska presenteras för företaget.</p><p>För att nå uppsatsens syfte har en fallstudiebaserad kvalitativ studie använts. En tydlig avgränsning av vad som ingår i undersökningen och vad som ligger utanför finns då uppsatsen enbart avsåg att undersöka ledningens syn på hur företaget arbetar med lönsamhetsstyrning. En kvalitativ ansats har använts för att genom en djupgående intervju belysa en helhet och med hjälp av mina egna tolkningar finna en förståelse i det undersökta.</p><p>En beskrivning på hur företaget, enligt ledningen arbetar med lönsamhetsstyrning har presenteras. Vidare har undersökningen resulterat i att brister i företagets arbetssätt funnits och förslag till hur de kan avhjälpas har presenterats. De rekommendationer som gjorts är att ACB Laminat AB måste lägga tid och resurser på att utforma ett för företaget lämpligt belöningssystem. För att skapa största möjliga gensvar bland företagets anställda rekommenderas antingen ett lönebaserat belöningssystem eller ett bonussystem baserat på produktionsresultat. Vidare anser jag att företaget ska analysera i vilka delar av management nivån bristerna finns för att sedan utföra de typer av åtgärder som krävs för att avhjälpa problemet.</p>
196

Traditionella flygbolag och Lågprisflygbolag : En jämförande studie av fem europeiska flygbolags operativa effektivitet och finansiella strategier

Karp, Christopher, Sahlström, Fredrik January 2008 (has links)
<p><strong>Frågeställning: </strong>Hur skiljer sig lågprisflygbolagens strategier jämfört med de traditionella, vilken är den vinnande strategin?</p><p><strong>Huvudsyfte: </strong>Genom utvalda teorier<strong> </strong>och nyckeltal jämföra och se skillnader mellan flygbolagens strategier och hur det påverkar lönsamhet och utveckling<strong>.</strong></p><p><strong>Metoder: </strong>En jämförande studie baserad på sekundärdata på fem stora flygbolag för att hitta olikheter i strategier. Främst används bolagens årsredovisningar, vetenskapliga artiklar och relevanta teorier för insamlandet av data.</p><p><strong>Slutsatser: </strong>Biljettpriset inom flygindustrin blir en allt viktigare faktor att anpassa sig efter för överlevnad på marknaden. Lågprisflygen har genom kostnadsreduceringar genom enklare bokningssystem, mindre personalstyrka, avlägsna flygplatser och enhetlig flotta kunnat sätta lägre priser än de traditionella. Detta innebär att effektiviteten har ökat och detta sätter press på de traditionella flygbolagen att kostnadsreducera och utveckla servicen ytterligare för att ha en chans att klara konkurrensen. Marginalerna har blivit mindre vilket pressar ner lönsamheten inom industrin. Traditionella flygbolag behöver anpassa sig efter de nya kraven och omstruktureringar är nödvändigt.</p> / <p><strong>Problem formulation:  </strong>How does the low price airlines strategies differ from the traditional airlines strategy, which is the winning strategy?</p><p><strong>Main purpose: </strong>With chosen theories and key figures see the differences between airlines strategy and how it affects profitability and development.</p><p><strong>Method: </strong>A comparing study based on secondary data from five big airlines in order to find differences in strategy. Mostly the companies' annual reports, scientific articles and relevant theories are used for the collection of data.</p><p><strong>Conclusions: </strong>It is becoming more important to adjust the ticket price on air travelling to survive on the aviation-market. Low-price airlines have been able to lower the ticket price through cost reductions with easier booking systems, smaller workforce, less attractive airports and a uniform fleet. This productivity increase is forcing the traditional airlines to reduce their costs and improve their service to deal with the competition. The marginal's are getting smaller and profitability is getting lower. Traditional airlines have to adjust after the new demands and restructures are needed.</p>
197

Impact of Liquidity Management on Profitability : A study of the adaption of liquidity strategies in a financial crisis

Lamberg, Sanna, Vålming, Sandra January 2009 (has links)
<p>The ongoing financial crisis which has upset the financial markets of the world since the late summer of 2007 has not left Swedish corporations unaffected. Strategies which can be adapted within the firm to improve liquidity and cash flows concern the management of working capital and cash management, areas which are usually neglected in times of favourable business conditions.</p><p>In this study it is examined how companies have adjusted their liquidity strategies before the crisis started to spread worldwide and a year afterwards, in the beginning of the 2009 when economies are in the middle of the turbulence, still feeling the consequences of the financial crisis and not yet started to recover. Research problem consisted of two main questions:</p><p><em>Do active liquidity strategies have a positive effect on company’s profitability in times of financial turbulence/ economic turbulence? </em></p><p><em> </em></p><p><em>Have the importance of key ratios in the measurement of liquidity changed during the time period?</em></p><p>The primary purpose of the study was to evaluate and compare the use and extent of the liquidity practices in two time points. Furthermore, the aim was to measure if the changing of liquidity strategy is related to the profitability measured by return on assets (ROA).</p><p>Sample consisted of companies listed on Stockholm Stock Exchange’s Small and Mid cap- lists, with some restrictions. The quantitative research strategy was employed and data was collected by using telephone interviews and financial ratios from financial statements. Hypotheses tested different aspects of cash management and liquidity practices. Statistical analysis was conducted by using regression analysis of the change scores and profitability.</p><p>Overall findings suggested that the adaptation of liquidity strategies do not have a significant impact on ROA. Only increased use of liquidity forecasting and short-term financing during financial crisis had a positive impact on ROA. Moreover, it was found that the importance of the key ratios monitoring companies liquidity have not changed between the studied time points. Working capital ratio is the most commonly used liquidity measurement and in addition the use of working capital and DIO metrics has increased most during the crisis.</p><p>More frequent monitoring and forecasting on liquidity levels and making more short-term investments can provide gains in profitability Based on the findings the adjustment of liquidity practices is beneficial for the companies, even though benefits are not always directly measurable in profitability. Furthermore, companies are recommended to maintain their focus on liquidity and working capital management in an economic downturn.</p><p> </p>
198

The Impact of Board composition on Accounting Profitability of the Firm : A Study of Large Caps in Sweden

Zemichael, Rahel Tsehaye, Basazinew, Serkalem Tilahun January 2010 (has links)
<p>Background: The issue about corporate governance became more prominent in recent years as a result of corporate scandals and misconduct of executives. Firms, board members, and executives have been subject to criminal and civil actions over hidden debt, inflated earnings, insider trading, tax evasion, misuse of funds, and breaches of fiduciary duties. Firms such as Enron, WorldCom, and Tyco became well-known because of huge failures in governance. In addition to the scandals, nowadays, we can see that the financial crises have brought attention for today’s debate of corporate governance issue as well.</p><p>Board is the major component of corporate governance like chief executive office (CEO), shareholders, stakeholders or community in general. This board is authorized to decide on the operations, management, and strategy of the company on behalf of the shareholders. Since the board members suppose to represent their interests.</p><p>Problem: What is the relationship between main board composition factors and firm’s accounting profitability?</p><p>Purpose: This thesis strives to analyze the level of correlation between selected board composition factors and accounting profitability of the Swedish Large Companies; by using appropriate statistical tools of correlation we aim to identify the association of selected variables.</p><p>Method: This research is conducted with sample of 63 large caps from the OMX Nordic Exchange-Stockholm and includes data from 2005 to 2009. We adopt the perspective of a shareholder and the philosophical stance of a positivist. The study uses quantitative method since our sample size is large enough to use the method.</p><p>Conclusion: The findings highlight that there is no significant relationship between some of the board composition factors namely- number of board directors, percentage of independent directors and experience of board member and the accounting profitability measure (Av. ROE) of Swedish large firms.</p><p>Where as, in case of the proportion of female directors, we do find a significant correlation between the accounting profitability measure (Av. ROE) and percentage of female directors of Swedish large firms. The correlation results show a positive relationship between the variables</p>
199

What Characterises Successful Stocks? : A case study of Swedish companies between 1995 and 2005

Forss, Gabriel January 2006 (has links)
<p>This paper discusses the indicators of financial success for Swedish companies from 1995 until 2005. Quarterly data on 42 Swedish companies were collected from the Datastream data base and analysed by using both portfolio analyses and parametric analysis. In this study, financial success is measured by using the acclaimed concepts of the Sharpe ratio and the Jensen’s Alpha. The Sharpe ratios of the companies are studied between 1995-2005 and this discussion is complemented by analysis of the Jensen’s Alpha in the second half of that time period i.e. 2000-2005. The relationship between these performance metrics and certain company-characteristics such as the book-to-market ratio, the ROA measure and capital structure is studied. The conclusion is that companies that have a high degree of profitability and maintain high book-to-market ratios outperform other companies in terms of generating excess returns to shareholders. Another interesting observation is the fact that company size does not have any significant relationship to company performance.</p>
200

Effet de l’alimentation à base d’Azolla sur la production du tilapia du Nil en zones humides au Bénin Effect of feeding with Azolla on production of Nile tilapia in Benin wetlands

ABOU, Youssouf 19 December 2007 (has links)
Résumé Une meilleure intégration de la fougère aquatique Azolla dans les aliments de O. niloticus en vue de sa production en milieu rural a été recherchée en bassins et en étangs. Six aliments (29,2 % PB; 16,9 kJ g-1 EB, chacun) : A0, A10, A20, A30, A40 et A50 contenant respectivement 0, 10, 20, 30, 40 et 50 % de farine d’Azolla (FA) en remplacement partiel de la farine de poisson ont été testés. En bassins comme en étangs, une réduction de la croissance a été enregistrée lorsque la teneur en FA a dépassé 10 et 20 % respectivement. En étangs, les valeurs de production piscicoles (8220-5120 kg ha-1 an-1) et d’indice de profitabilité (0,42-0,89) sont similaires jusqu’à 20 % et 30 % de FA dans les aliments. L’élevage en étangs pourrait être plus avantageux en nourrissant les poissons avec A20 en étangs dont la surface est couverte à 45 % par un tapis d’Azolla. Dans les deux systèmes d’élevage, la composition des carcasses ne semble pas être affectée, excepté une réduction de la teneur en lipides totaux dans les poissons nourris avec A30, A40 et A50 en bassins et ceux nourris avec A50 en étangs. D’un point de vue environnemental, malgré que la teneur en phosphore des aliments soit passée de 1,13 % à 0,76 % en faisant varier leur teneur en Azolla de 0 % à 50 %, les compositions en phosphore (P) et azote (N) des poissons sont similaires, en bassins comme en étangs. En bassins, les quantités de P et de N rejetées par les poissons ont diminué avec l’augmentation de FA dans les aliments. De même, la quantité de P rejetée en étangs décroît, tandis que celle de l’azote est identique dans tous les traitements. La composition en acides gras des poissons élevés en bassins ressemble à celle des aliments, excepté une augmentation de la teneur en acide arachidonique (ARA) chez les poissons nourris à fort taux d’Azolla. Ceci pourrait être le fait d’une élongation et désaturation de l’acide linoléique. Les valeurs du ratio n-3/n-6 (0,08-0,17) qui en résultent sont faibles chez les poissons nourris avec A40 et A50. Le profil en acides gras des poissons d’étangs est par contre différent de celui des poissons de bassins et de la composition des aliments. Cette dissemblance est particulièrement prononcée chez les poissons nourris avec A30, A40 et A50 qui sont riches en acide éicosapentaénoique (EPA) et acide docosahexaénoique (DHA), principaux acides gras dans le plancton. Cette "signature" du plancton pourrait être due à une consommation supplémentaire de ces nourritures naturelles par ces poissons et expliquerait les valeurs élevées du ratio n-3/n-6 (0,35-0,53) dans les poissons nourris avec les aliments contenant 20 à 50 % de FA. Les paramètres de croissance et le profil en acides gras sont meilleurs en étangs qu’en bassins, et les nutriments rejétés en étangs sont relativement faibles, probablement à cause de la contribution de la nourriture naturelle. En conclusion, Azolla pourrait permettre de réduire le coût des aliments et le coût total de production des poissons, tout en garantissant un bon niveau trophique des étangs et une bonne qualité nutritionnelle des poissons produits. L’étude suggère d’utiliser la fougère jusqu’à 10 % dans les aliments en bassins et 20 à 30 % en étangs. Dans ce dernier système, une couverture des étangs de maximum 45 % de leur surface pourrait permettre de produire des poissons, en même temps qu’elle fournirait de l’Azolla à incorporer dans les aliments ou pour d’autres utilisations bénéfiques. Abstract An improved integration of the aquatic fern Azolla in diets for production of Nile tilapia O. niloticus in rural area was investigated in tanks and in ponds. Six diets (29.2% CP; 16.9 kJ g-1 GE, each) were tested, containing 0% (diet A0), 10% (diet A10), 20% (diet A20), 30% (diet A30), 40% (diet A40) and 50% (diet A50) of Azolla meal (AM) as fishmeal (FM) substitutes. The diet A0 served as a control. Growth parameters decreased, significantly when Azolla level exceeds 10% and 20% in diets, respectively in tanks and ponds. In ponds, the variation of annual fish production follows the trend in growth parameters, with values decreasing from 8220 to 5120 kg ha-1 year-1. Identical profitability index (range: 0.42-0.89) was obtained up to 30% Azolla. Feeding with A20 could be more advantageous by rearing fish in ponds covered with Azolla mat at a maximum of 45% of the water surface. In tanks and in ponds, fish carcass was not significantly affected, except for the total lipid content of fish fed 30, 40 and 50% Azolla in tanks, and those fed 50% Azolla in ponds. From an environmental point of view, phosphorus and nitrogen contents in experimental fish show similar values, both in tanks and ponds, although phosphorus content in diets varied from 1.13% to 0.76% when Azolla level increased from 0% to 50%. In tanks, phosphorus (P) and nitrogen (N) discharged as wastes by fish decreased with increasing Azolla level in diets. Also, P decreased significantly in ponds whereas identical values were found for nitrogen in all treatments. In tanks, fish fatty acids mirror the profile in diets, except for the high arachidonic acid content (ARA) in high AM-fed fish, probably as a result of elongation and desaturation of linoleic acid. This leads to a lower n-3/n-6 ratio (range: 0.08-0.17) in fish fed A40 and A50. Fatty acid composition of fish fed in ponds was different from that in fish fed in tanks, and from diets. The lower resemblance of fish composition was more pronounced in fish fed A30 to A50 in which large amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were found, reflecting closely the composition in plankton. The reason could be a supplemental consumption of plankton by those fish as a response to the deficiency in diets A30-A50. Then, the n-3/n-6 ratios (range: 0.35-0.53) were higher in fish fed A20 to A50. Growth and fatty acid composition were better in ponds, and nutrients loading into pond water were lower, probably due to the contribution of natural foods. In conclusion, Azolla use leads to reduced feed and total fish production costs, while ensuring a suitable pond trophic level and a good nutritional quality of the fish produced. The study suggests using Azolla in tanks up to 10% in diets, while up to 20-30% can be recommended in ponds. In the latter case, covering the ponds surface with Azolla mat at a maximum of 45% of its surface could lead to produce fish, while ensuring Azolla mass production for diets and other beneficial utilization.

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