Innovative approaches in aquaculture for conservation and management of threatened fish species: the case of different strains of brown trout (Salmo trutta and Salmo ghigii)

Abstract

Innovative approaches in aquaculture for Conservation and management of threatened fish species: the case of different strains of brown trout (Salmo trutta and Salmo ghigii) Abstract In Salmonid species, direct factors that affect sperm concentration are culture conditions, stripping time, age, feeding and presence of males. It is reported that inside culture conditions, temperature of water can strongly influence quality of fish sperm, especially duration of motility. The aim of first part of this work is evaluate the quantity of fish milt in different Salmonid lineages; Atlantic brown trout (Salmo trutta), an albino strain of Mediterranean brown trout (Salmo ghigii), a pure Mediterranean lineage (Salmo cettii) and marble trout (Salmo marmoratus). Brown trout (Salmo trutta) have long been a favourite sport-fish among anglers, and have been transported primarily on the basis of recreational fishing. A balanced diet and proper feeding practices are important in aquaculture. It is necessary to have a proper amount of feed with ingredients necessary for fish such as protein for normal tissue function, maintenance and renewal of the fish body, carbohydrates and lipids for energy source, vitamins and minerals for body functions, growth, reproduction and maintenance of fish metabolism. The second part of an experiment conducted at the University of Parma in Italy in the summer 2016, and the aim is to investigate the effects of dietary black carbon on growth performance and survival rate of brown trout (Salmo trutta). Different factors such as Chemical, Physical, and perceived stressors can all evoke non-specific responses in fish, which are considered adaptive to enable the fish to cope with the disturbance and maintain its homeostatic state. Fish faced with stressful stimuli launch an endocrine stress response through activation of the hypothalamic-pituitary-interrenal (HPI) axis to release cortisol in to the blood. Scientifically validated biomarkers to capture systemic cortisol exposure over longer periods of time are of utmost importance to assess chronic stress in governmental, wild life, aquaculture and scientific settings. Cortisol is the main corticosteroid hormone in teleost secreted in response to stressor exposure and plays a key role in stress adaptation. The aim of last part of study is to check difference in stress resistance between wild type of Atlantic brown trout (Salmo trutta) and albino Mediterranean trout (Salmo ghigii). An experiment conducted at Monchio fish hatchery of Parma province in Italy during the summer 2017. Considering that, stress parameters effect on behavioral changes, and mentioned changes can increase stress, as well as reducing reproduction and decreasing growth rate and health status, consequently, the ability of stress factor managing and reducing these parameters have an important role for protection and conservation of endangered species.