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This book is a unique cross fertilization of aquatic ecology and aquaculture. It shows how diets structure the digestive tract and its microbiota and, in turn, the microbiota influences life history traits of its host, including behavior. Short-term starvation can have beneficial effects on individuals themselves and succeeding generations which may acquire multiple stress resistances – a mechanism strengthening the persistence of populations. From terrestrial, but not yet from aquatic animals, it is understood that circadian the rhythmicity makes toxins or good food. On the long-term, the dietary basis impacts succeeding generations and can trigger a sympatric speciation by (epi)-genetics. This volume defines gaps in nutritional research and practice of farmed fishes and invertebrates by referring to knowledge from marine and freshwater biology. It also points out that dietary benefits and deficiencies have effects on several succeeding generations, indicating that well designed diets may have the potential to successfully improve broodstock and breeding effort.

Not all stress is stressful; instead, it appears that stress in the environment, below the mutation threshold, is essential for many subtle manifestations of population structures and biodiversity, and has played a substantial role in the evolution of life. Intrigued by the behavior of laboratory animals that contradicted our current understanding of stress, the author and his group studied the beneficial effects of stress on animals and plants. The seemingly “crazy” animals demonstrated that several stress paradigms are outdated and have to be reconsidered. The book describes the general stress responses in microorganisms, plants, and animals to abiotic and biotic, to natural and anthropogenic stressors. These stress responses include the activation of oxygen, the biotransformation system, the stress proteins, and the metal-binding proteins. The potential of stress response lies in the transcription of genes, whereas the actual response is manifested by proteins and metabolites. Yet, not all stress responses are in the genes: micro-RNAs and epigenetics play central roles. Multiple stressors, such as environmental realism, do not always act additively; they may even diminish one another. Furthermore, one stressor often prepares the subject for the next one to come and may produce extended lifespans and increased offspring numbers, thus causing shifts in population structures. This book provides the first comprehensive analysis of the ecological and evolutionary effects of stress.

Humic Substances color all waters more or less brown. Their concentrations exceed all carbon of living organisms by at least one order of magnitude. Opposite to former paradigms, they participate in almost any metabolic pathway. They protect against UV-irradation, enable indirect photolysis and, thus, purify hazardous chemicals, they provide inorganic and organic nutrients, may form cryptic genes with DNA and dampen metabolic fluctuations. More recently they can increase adverse effects of hazardous chemicals and they can directly interfere with organisms. The book tries to relate effects to structural features.

The Enigmatic Academy is a provocative look at the purpose and practice of education in America. Authors Christian Churchill and Gerald Levy use three case studies—a liberal arts college, a boarding school, and a Job Corps center—to illustrate how class, bureaucratic, and secular-religious dimensions of education prepare youth for participation in American foreign and domestic policy at all levels. The authors describe how schools contribute to the formation of a bureaucratic character; how middle and upper class students are trained for leadership positions in corporations, government, and the military; and how the education of lower class students often serves more powerful classes and institutions. Exploring how youth and their educators encounter the complexities of ideology and bureaucracy in school, The Enigmatic Academy deepens our understanding of the flawed redemptive relationship between education and society in the United States. Paradoxically, these three studied schools all prepare students to participate in a society whose values they oppose.

As sequel to Aquatic Animal Nutrition – A Mechanistic Perspective from Individuals to Generations, the present treatise on organic macro- and micronutrients continues the unique cross fertilization of aquatic ecology/ecophysiology and aquaculture. This treatise considers proteins and their constituents, carbohydrates from mono- to polysaccharides, fatty acids from free acids to fat, and waxes. It becomes obvious that these organic nutrients are more than only simple fuel for the metabolism of animals; rather, their constituents have messenger and controlling function for the actual consuming individual and even for succeeding generations. This aspect will become particularly clear by putting the organisms under consideration back into their ecosystem with their interrelationships and interdependencies. Furthermore, micronutrients, such as vitamins and nucleotides as well as exogenous enzymes, are in the focus of this volume with known and still-to-be-discovered controlling physiological and biomolecular functions. Aquatic Animal Nutrition – Organic Macro and Micro Nutrients addresses several gaps in nutritional research and practice. One major gap is the lack of common research standards and protocols for nutritional studies so that virtually incomparable approaches have to be compared. This applies also to the studied animals, since most approaches disregard intraspecific variabilities and the existence of epimutations in farmed individuals. Furthermore, recalling the Mechanistic Perspective from Individuals to Generations, dietary benefits and deficiencies have effects on succeeding generations. In most studies, this long-term and sustainable aspect is overruled by pure short-term production aspects. By comparing nutritional behavior and success of fishes and invertebrates, Aquatic Animal Nutrition points out different metabolic pathways in these animal groups and discusses how, for instance, fishes would benefit when having some successful metabolic pathway of invertebrates. Application of novel genetic techniques will help turn this vision into reality. However, a widely missing link in the current nutritional research is epigenetics regarding transgenerational heritages of acquired morphological and physiological properties. To increase public acceptance, nutritional optimization of farmed animals based on this mechanism, rather than genetical engineering, appears promising.

This volume first covers the supplementation of aquafeeds with terrestrial plant material used in human medicine and nutrition. Mainly based on the “trial and error” approach, many supplements enhance growth, immunity and resistance to stress. However, other supplements appear to be ineffective and some have adverse effects. A robust and guiding hypothesis for supplementation is not apparent. Therefore, the book proposes the use of artificial intelligence to end the trial-and-error phase. In addition, a graded dosing is rarely used, especially in the low-dose range, so the physiological mechanisms behind the supplements are often only partially understood. This topic of aquatic animal nutrition is still in its infancy. Chapters cover medicinal plants in general, selected medicinal plants in detail, food plants, fruits, essential oils, fermentation residues, and genetically modified plants. One chapter attempts to answer the question of what mechanism may underlie ineffective or even harmful supplementation. Overall, the importance of the intestinal microflora is becoming increasingly clear and points to the imperative need to include gut microbiota in replacement studies. Based on the few epigenetic studies currently available, the importance of these processes is demonstrated. The need to integrate such approaches into future studies is emphasized. The so-called hologenomics approach is inevitable. Can adverse effects be mitigated by adding functional feed ingredients such as prebiotics or probiotics? This volume concludes with aquatic plants (macroalgae, filamentous algae, and macrophytes) as food sources for natural and farmed aquatic animals. Can aquaculture learn from natural aquatic herbivores?

Associations of marine algae with symbiotic or parasitic microorganisms are ubiquitous phenomena known for a long time. However, there is an almost complete lack of knowledge on details of such interactions. The intention of this study is to use the potentials of modern biological and biochemical techniques in order to analyze the reaction of brown algal hosts to the attack by pathogens and epibionts. A 3-year field study at different localities on the European Atlantic coast revealed that Pylaiella littoralis populations were subject to massive epidemics of the parasites Eurychasma dicksonii, Chytridium polysiphoniae and Anisolpidium rosenvingei. Laboratory cultures were used to investigate the association of Eurychasma and Chytridium with brown algal hosts from different taxonomic groups: Eurychasma has a much broader host range than Chytridium, comprising members of all brown algal orders investigated, and it tolerates a wider range of temperatures than the latter. Phylogenetic studies based upon 18 S rRNA genes revealed that Eurychasma dicksonii belongs to the Oomycota, branching at an ancestral position between terrestrial plant pathogens and free-living members of the marine heterotrophic picoplankton. Chytridium polysiphoniae, a fungus, appears more closely related to the genera Rhizophydium and Spizellomyces (Chytridiomycota) than to other known Chytridium species. Chytridium produces chitin, whilst Eurychasma does not. Early stages of Eurychasma infection have a rather modest effect on host physiology. The photosynthetic capacity is enhanced, suggesting a temporary stimulation of host metabolism for hypertrophic growth. Chytridium, in contrast, has an immediate detrimental effect on host photosynthesis, which breaks down once a cell is infected, leading to the rapid death of infected cells.