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M.S.

Epioblasma capsaeformis, commonly named the oyster mussel, once occupied thousands of miles of stream reaches, but has now been reduced in range to small, isolated populations in a few river reaches. Due to this significant decline in population numbers, a study was conducted to develop a diet for propagating this endangered species under captive conditions. Oyster mussel juveniles were collected from several sites on the Clinch River and sacrificed for gut content and biochemical composition analyses in summer. Feces and pseudofeces from live river-collected juveniles were examined seasonally for algae, detritus, and bacteria to qualitatively determine diet of specimens. Two feeding trials also were conducted in this study to evaluate effect of diet (commercial and non-commercial diets), on growth and survival of oyster mussel juveniles. From examination of gut contents, fecal and pseudofecal samples, it was apparent that algae and a significant amount of detritus (~90%) composed wild juvenile diets. E. capsaeformis juveniles (1-3 y of age) could have fed on particles up to 20 µm in size and seemed they were mostly ingesting particles within the 1.5-12 µm size range. Protein content of sacrificed juveniles ranged from 313 to 884 mg/g and was highly variable. Glycogen content ranged from 49-171 mg/g. Caloric content of four juveniles ranged from 2,935.10 to 4,287.94 cal/g, providing a preliminary baseline range for future energetic studies on freshwater mussels. Growth was significantly higher in those juveniles fed the triple concentration algae-mix (62,076 cells/ml) than all other diets tested in trial 1. Results of both feeding trials indicated that survival of juvenile oyster mussels was enhanced when fed an algal diet supplemented by bioflocs. / Master of Science

The purpose of this study was to determine attitudes toward low carbohydrate diets among consumers and the attributes that influence their purchase decision. A growing number of diet trends are spreading across the nation in an effort to improve health and lose weight such as the Atkins diet and the South Beach diet.

The main objective of this thesis was to gain new insights in three of Florida’s high value food and stock enhancement finfish nutrition (Common snook, Florida pompano and red drum) to improve larviculture protocols. The main bottleneck in snook production is the extremely low larval survival rate, which hinders subsequent research. This work first focused on the source of the larvae by looking at potential nutritional deficiencies in captive broodstock. The lipid composition of wild and captive common snook broodstock were compared to identify disparities and gain the information necessary for the formulation of a suitable diet for captive stocks. Results showed that captive snook lipid content was significantly higher than that of wild fish. However, cholesterol and arachidonic acid (ARA) levels were significantly lower compared to wild broodstock, with potential impact on steroid and prostaglandin production, reproductive behavior and gametogenesis. Eggs from captive broodstock incorporated high docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels and low ARA levels. Consequently, ARA/EPA ratio in captive eggs was more than half of that in wild eggs (2.3 ± 0.6 and 0.9 ± 0.1 respectively), with a probable perturbation in eicosanoid production and adverse effects on embryo and larval development. The large differences observed between wild and captive broodstock most likely contributed to the reproductive dysfunctions observed in captive snook broodstock (e.g. incomplete oocyte maturation, low milt production and poor egg quality). In addition, the presence of hydrocarbons was detected in the liver of most of the wild snook sampled. This requires further investigation to identify the source of the contamination, monitor a potential impact on reproductive performances and protect the species habitat. Another major bottleneck in marine fish rearing occurs during the transition from endogenous feeding to exogenous feeding, with mass mortality events linked to inadequate first feeding diets. To gain insight on the early fatty acid requirements and mobilization of pompano and snook larvae, the pattern of conservation and loss of fatty acids from the yolk sac during the endogenous feeding period and subsequent starvation was studied. In both species, fatty acids were utilized as an energy source after hatching. Mono-unsaturated fatty acids were catabolized, while saturated and poly-unsaturated fatty acids were conserved. High levels of arachidonic acid (ARA) in pompano and snook eggs (respectively 2.44 ± 0.1 and 5.43 ± 0.3 % of total fatty acids), as well as selective retention in the unfed larvae, suggested a high dietary requirement for this fatty acid during the early stages of larval development. The effect of an ARA supplementation was therefore investigated in snook larvae at the rotifer feeding stage. Larvae receiving the supplementation did incorporate higher levels of ARA, and DHA/EPA and ARA/EPA ratios were successfully modified to match those observed in wild eggs. No significant improvements in growth or survival were observed, however the success in fatty acid profile modification suggest a possible impact of the supplementation on a longer period of time and a possible effect on stress resistance. Probiotics have been shown to enhance larval performances of several species and this strategy was therefore investigated to evaluate a potential impact on Florida pompano, red drum and common snook larvae. The effect of a commercial mix of Bacillus sp. was studied on larval survival, growth and digestive enzyme activities. Larvae were fed either live feed enriched with Algamac 3050 (Control), Algamac 3050 and probiotics (PB), or the previous diet combined with a daily addition of probiotics to the tank water (PB+). Microbiological analyses were performed at the end of the pompano trial. Numbers of presumptive Vibrio sp. were low and not statistically different between treatments, therefore no additional microbiological analyses were performed on the system. At the end of the pompano and snook trial, standard lengths of larvae from the PB and PB+ treatments were significantly greater than for the control larvae. For both pompano and snook, trypsin specific activity was higher in PB and PB+ larvae compared to the control larvae. Similarly, alkaline phosphatase activity was higher for the pompano larvae fed the PB and PB+ treatments and for the snook larvae fed the PB+ treatment compared to the control larvae. No enhancement of growth or digestive enzymes activities was observed in red drum larvae. Yet, no negative effects were noticed and a longer trial period and the study of additional parameters could reveal different effects. In all three species, survival was not affected by the supplementation; however, stress exposure should be further investigated as the supplementation may strengthen the larvae, especially pompano and snook larvae where the Bacillus sp. supplementation appears to promote growth through an early maturation of the digestive system. Another key challenge in marine fish larval rearing resides in weaning the larvae onto dry micro-diets. This step is commonly concurrent with larvae metamorphosis into juveniles, with extensive morphological and physiological changes that are likely to influence nutritional requirements. In the present project, three microdiets were tested on weaning of Florida pompano larvae: Otohime, Gemma and a reference diet LR803. The experimental system was stocked with 11-day-old larvae, which were co-fed micro-diets and live food from 11 dph to 17 dph then micro-diets only until 28 dph. Survival from 11 dph to 28 dph was similar for all treatments, with an average of 33 %. At the end of the trial, the Gemma larvae were significantly longer and heavier than larvae fed the other diets. Fatty acid composition of the diets and larvae varied significantly between treatments. The Gemma larvae incorporated the lowest amount of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (ARA). However, they presented the highest DHA/EPA and ARA/EPA ratios, supporting the concept that the proportions of polyunsaturated fatty acids are of greater importance than their absolute amount. Results from the enzyme analysis showed that fishmeal is a suitable main source of protein for Florida pompano larvae and demonstrated the full functionality of the pancreas at 16 days post hatch. These results provide the basis of a suitable weaning diet for pompano larvae and indicate the possibility of a weaning time prior to 16 days post hatch, which is of high interest in commercial production. Overall, this research provides new data on common snook, pompano and red drum nutritional requirements with results that can be directly applied to help overcome major bottlenecks in the hatchery phase and improve rearing protocols.

Fish meals (FM) and fish oils (FO) are used extensively as the main protein and lipid sources respectively in industrially compounded salmon feeds, mainly due to their excellent nutritional properties. Nevertheless, several reasons dictate the utilisation of sustainable alternative protein and lipid sources and the subsequent reduction in the reliance on fishery-products in aquafeeds. Soy protein concentrate (SPC) is a very promising alternative to FM Hence, the main objective of the present thesis was to investigate the effects of the increased substitution of FM withSPC, lysine and methionine on the growth performance and immune responses of early and late stage Atlantic salmon parr prior to and after vaccination with commercial vaccines (Experiments II and V presented in Chapters 4 and 6). Furthermore the effects of increasing dietary levels of SPC with consistent and/or increasing dietary supplementation of phosphorus on the Atlantic salmon parr’ body proximate and mineral composition or the skeletal mineral composition respectively, prior and post-vaccination with commercial vaccines; under continuous light or under 12 hours light: 12 hours dark photoperiod (Experiments I and V presented in Chapters 3 and 5 respectively). Lastly the impact of FM-, FO- and fishery-free diets on the growth, carcass proximate composition and immune status of Atlantic salmon post-smolts was investigated (Experiment III presented in Chapter 7). In the latter experiment six diets were tested including: two commercially applied marine based diets, one with partial inclusion of vegetable proteins (VPs) and oils (VOs) according to the EU standards (2011-12) (MBE) and one with partial inclusion of VPs, VOs and land animal-by product (ABP) proteins according to the non-EU standards (MBABP); a fully vegetable protein (VP) diet; a fully algal and vegetable oil (VO) diet; a marine-free VP and VO and algal oil diet (VP/VO) diet; and a marine-free diet with a mix of VPs and land ABP proteins and lipid from VOs and algal oils (MFABP). The results of the Experiments I and II (Chapters 3 and 4) show that late Atlantic salmon parr can grow efficiently on SPC80 diets, however, they require longer periods to adapt to these diets compared to fish fed diets containing lower levels of SPC as a protein source. Decreased mineralisation of body cross-section was observed for salmon fed increasing dietary SPC. Vaccination improved mineralisation for the high dietary SPC salmon groups. However, continuous light exposure promoting fast growth appeared to be detrimental for Atlantic salmon body cross ash, Ca, Mg, Mn, P and Zn. Moreover, it was demonstrated that substitution of up to 50% of high quality FM protein with SPC and constantly added P has the minimum possible impact on late salmon parr growth, whereas it stimulates several immune parameters prior to immunisation. Immunostimulatory effects were also shown for the diets with higher dietary SPC levels. It is not clear if these results were an effect of increased FM replacement with SPC or not properly balanced levels of dietary P. The Experiments III and IV (Chapters 5 and 6) illustrated that early stage Atlantic salmon parr can accept diets with up to 58% protein from SPC without serious effects on body growth. However, higher levels can severely affect salmon growth performance. Moreover, it was shown that long-term feeding of salmon with increasing dietary SPC combined with increasing phosphate supplementation, alone or in combination with vaccination can actually be beneficial for Atlantic salmon parr bone mineralisation. However, mineralisation in vaccinated fish was higher than in PBS-injected fish. This could be linked to the slower growth of vaccinated salmon allowing their developing bones to mineralise properly. Changes in the modulation of the different components of the complement activity was revealed in Atlantic salmon fed increasing dietary levels of SPC. The modulation of complement activity was demonstrated at both studies utilising increasing dietary SPC concentrations, indicating that complement componenets are among the most prominent immunological markers upon dietary FM replacement with SPC. However, overall no differences in total complement activity and therefore the immune capacity and resistance against Aeromonas salmonicida were observed among the salmon groups receiving increasing levels of SPC. Lastly in Experiment V (Chapter 7) higher growth performance indices (weight gain, SGR and TGC) were evident in the MBE salmon compared to the MBABP group, salmon fed diets with complete eleimintion of FM or FO (VP and VO respectively) and fish fed two diets with total substitution of both marine derived feed ingredients, three months after the start of the feeding trial. Higher feed intake was demonstrated for both MBE and VP salmon compared to the other groups for the duration of the first period. The above results could have been influenced by discrepancies in the size of the fish at the start ofthe trial, revealing flaws in the experimental design. Both MBE and VP salmon groups also presented the highest feed conversion ratios, revealing the lowest efficiency in dietary nutrient utilisation in comparison to the rest of salmon which exhibited no differences in feed efficiency, revealing an overall better performance of the MBABP and diets with low levels of marine feedstuffs. Improved FI compared to the values of the first period and higher SGR and TGC values were demonstrated for salmon from the latter treatments compared to MBE and VP salmon, during the second part of the study, revealing compensatory growth for these groups. VP salmon demonstrated the highest and VO salmon the lowest condition factor values. The former finding might possibly be related with higher fat accumulation in the viscero-hepatic tissues. No differences were observed in carcass moisture, protein, fat and ash concentrations among the dietary groups of fish. Furthermore, no differences were demonstrated in terms of total and differential leucocyte counts, plasma haemolytic activity, plasma protein and total IgM levels, stimulated and non-stimulated HKM burst activity among the different dietary groups. However, lower haematocrit values were observed in the MB and VO-fed groups compared to the MFABP and VP/VO groups. Furthermore, decreased lysozyme activity was observed for all diets in contrast to the control groups, whereas FM-free diets promoted plasma anti-protease activity. The former result could have been an effect of either immune or stress induction, whereas the second is regarded as an immunostimulatory effect. The results suggest that marine-oil, marine-protein and marine-free diets could be satisfactorily used for Atlantic salmon post-smolts without severe reductions in their innate immune responses, although longer adaptation periods might be required for the fish to fully accept these diets.

The Bohemian land diet represents one of the most important institutions of the Bohemian estate monarchy in the late Middle Ages and early modern period, whose actions had considerable influence not only on the Czech kingdom itself, but often touched whole Land of the Bohemian Crown and surrounding states. This master thesis deals with the Bohemian Land Diets extensively between the years 1500 to 1526, focusing on how disability aspects of the functioning of the then land diets in the estates society and on individual topics and problems, which were on the diets discussed. Thesis deals with the organization of the diets, which are described and evaluated from their initiating, via the usual course of negotiations and meetings until their closure and completion. Particular areas of their interests are processed in the form of thematic summary of the topics of their negotiations.

Food consumption plays an important role for future sustainable livelihoods and, in particular, the vegan diet is becoming increasingly popular among consumers of different societies. Understanding how people change their food habits is a major research quest and there is growing interest in the role of social media sites since these are important platforms for visual presentation online where individuals can influence others. This article investigates how vegan ‘men’ present themselves on the social media network Instagram. Drawing on the analytical framework of ‘hegemonic masculinity’, the study examines what values these individuals visually portray online. By conducting a content analysis of 600 top-posts that appear under the hashtag #veganmen, narratives are examined for what they convey and how certain ‘masculine’ perceptions are re-shaped or reinforced. The findings reveal the visual significance of ‘masculine’ self-presentation by vegan ‘men’ over other narratives that portray values of sustainability, compassion and empathy. Nonetheless, this narrative of ‘masculine’ self-presentation can still be understood as an attempt to motivate other individuals to embrace a plant-based diet and thereby contribute to change towards more ‘sustainable’ food consumption habits.

The purpose of this qualitative research paper was to explore how companies who offer plant-based meat and dairy substitutes in the Swedish market, can influence flexitarians towards a more plant-based diet. This was based on the conflict between the need to substitute animal products with more plant-based alternatives and the current resistance among consumers to change from traditional eating patterns. A qualitative research approach was adopted, where seven semi-structured interviews were conducted in the empirical data collection process. The sample included six leading brands in the Swedish market, namely Oatly, Oumph!, Sproud, Violife, Fry and ICA, and one industry expert named Mattias from Vegomagasinet. The research identified seven themes where two of them were most significant; the need to direct the communication to flexitarians and the importance of creating a taste and texture that is similar to meat and dairy. The five remaining influential factors concerned collaborations with stakeholders, challenging packaging design, transformative marketing, earned media and premium prices.

Quatro experimentos foram conduzidos com o objetivo de avaliar o efeito da forma física da ração pré-inicial no desempenho e na alometria de órgãos do sistema digestório de frangos de corte, provenientes de ovos de pesos semelhantes ou distintos, produzidos por matrizes Ross de idades diferentes. Foram utilizados 2.340 ovos para os experimentos 1 e 2 e 2.160 ovos para os experimentos 3 e 4. A composição percentual dos ovos foi avaliada. Os experimentos 1 e 2, assim como os experimentos 3 e 4, ocorreram simultaneamente. O experimento 1 contou com 1.380 pintos de um dia, machos e fêmeas sexados, provenientes de ovos com peso médio de 57,8 g ou 68,8 g, de matrizes com, respectivamente, 29 e 55 semanas. O experimento 3 contou com 1.380 aves provenientes de matrizes com 29 e 55 semanas de idade, sendo o peso médio dos ovos padronizado em aproximadamente 62 g. O delineamento experimental utilizado foi o inteiramente casualizado, com seis tratamentos e cinco repetições, em esquema fatorial 2x3 (idade da matriz x forma física da ração pré-inicial). Na fase pré-inicial, a forma física da ração foi diferenciada em farelada, triturada e micro-peletizada, com fornecimento fixado em 200 g/ave. Do término da fase pré-inicial até os 42 dias de idade, foi fornecida uma ração comum farelada, para todos os tratamentos. Os parâmetros de desempenho avaliados nos experimentos 1 e 3 foram: ganho de peso, consumo de ração, conversão alimentar e viabilidade criatória. O tempo utilizado para o consumo total da ração pré-inicial foi monitorado. Para a avaliação da alometria de órgãos (intestinos delgado e grosso, fígado, pâncreas, proventrículo, moela e saco vitelino), foram utilizados em cada experimento (2 e 4), 240 pintos de um dia, machos e fêmeas sexados, nos mesmos tratamentos adotados nos experimentos 1 (pesos distintos) e 3 (pesos semelhantes). Foram sacrificadas seis aves provenientes de cada idade de matriz ao alojamento e quatro aves por tratamento nos dias três, cinco, sete, 14 e 21, sendo cada ave considerada uma unidade experimental. A gema de ovos provenientes de matrizes adultas foi maior mesmo quando estes apresentavam pesos semelhantes aos de matrizes jovens. Em ambos os experimentos de desempenho, melhores resultados foram obtidos pelos frangos provenientes de matrizes de 55 semanas de idade, bem como, por aqueles que consumiram rações pré-iniciais processadas. As aves levaram menos tempo para consumir 200 g de rações processadas do que farelada. Ao alojamento, moela, proventrículo, fígado e intestino delgado foram mais pesados para as aves oriundas de matrizes adultas, quando estas apresentavam pesos iniciais superiores aos das aves de matrizes jovens. O desenvolvimento do pâncreas, intestino delgado, fígado e proventrículo na primeira semana de vida foi superior ao crescimento corpóreo das aves, independente da idade da matriz. Conclui-se que o peso do ovo influencia o peso do pinto à eclosão, porém, é a idade da matriz que atua sobre o desempenho de frangos de corte. Além disso, o consumo de dietas processadas na fase pré-inicial favorece o desempenho dos frangos até os 42 dias de idade. / Four trials were conducted to evaluate the physical form of pre-starter diets on performance and allometric growth of gastrointestinal organs of chickens from eggs having the same or different weights, hatched from Ross breeders of different ages. In trails1 and 2, 2,340 eggs were incubated and in trails 3 and 4, 2,160. The eggs percentage composition was evaluated. Trials 1 and 2, as well as trials 3 and 4, were carried out simultaneously. After hatching, 1,380 day-old chicks, males and females, from young breeders (29 weeks) or adult breeders (55 weeks) were used in performance experiments: in experiment 1 the eggs weighted 57,8 g or 68,8 g, respectively, and in experiment 3, egg weight was standardized at 62 g. The performance trials were conducted in a completely randomized design with 6 treatments and 5 replicates, and the treatments consisted of a 2 3 factorial arrangement of breeder age (young and adult) and physical form of the pre-starter feed (mash, crumbled or micro-pellets). This feed was provided at a fixed amount of 200 g per chick and, after that, the birds in all treatments were fed a common starter, grower and finisher diet in mash form, to 42 days of age. Live weight, weight gain, feed intake, feed conversion and viability were evaluated on a pen basis. The time required for total consumption of the pre-starter feeds was monitored. To evaluate the allometric growth of gastrointestinal organs (small and large intestines, liver, pancreas, proventriculus, gizzard and yolk sac), in experiments 2 and 4, 240 one-day-chicks, males and females, were distributed to six pens with the same treatments as experiments 1 and 3, respectively. Six chicks from each breeder age on the first day and four chicks at ages three, five, seven, 14 and 21 days were sacrificed. The experimental unit was each chick. The yolk from adult breeder eggs was heavier, even when the eggs had similar weight of those from young breeders. In both performance trials, better results were obtained for chickens from adult breeders, as well as, for chickens fed processed pre-starter diets. The chickens consumed 200 g of processed diets faster than the mash diet. On the first day, gizzard, proventriculus, liver and small intestine were heavier in chicks from adult breeders than in chicks from young breeders, when the former presented heavier initial weight. Pancreas, small intestine, liver and proventriculus development was superior to body growth, independent of breeder age. It is concluded that egg weight influences the chick weight at hatching, however, breeder age affects the overall performance of the chickens. Furthermore, processed feeds benefit the chicks in the pre-starter phase and this benefit is maintained in the broilers to market weight.