Juvenile tench ( Tinca tinca L.) response to practical diets with different replacement levels of fish meal by pea protein concentrate supplemented with methionine

.The effects of methionine supplementation in diets with different replacement levels of fish meal (FM) by pea protein concentrate (PPC) on survival, growth performance and body composition of juvenile tench (0.39 g of initial weight) were studied in a 90-day experiment. Six practical diets (50% crude protein) differing in replacement level of FM by PPC were tested: 0% (control diet), 35%,45%, 60%, 75% or 85%, corresponding to 0, 285, 366, 487, 608 and 685.4 g PPC kg−1 diet respectively. To provide the same amount as in control diet, methionine was included from the 45% substitution level. Survival rates were high, between 93.7% and 100%, without differences among treatments. Juveniles fed 75% and 85% of replacement diets showed lower (p < 0.05) weight and specific growth rate, which cannot be attributed to methionine deficiency. In all treatments, percentages of fish with externally visible deformities were low (under 0.1%). The increase in PPC diet content resulted in a significant reduction of lipid content in whole-body juvenile. Minimum methionine requirements for juvenile tench could be estimated in 10 g kg−1 diet and supplementation over this amount would be not necessary. Juvenile tench exhibited a high tolerance to PPC dietary content, up to 487 g kg−1, without affecting growth performance, which make possible to consider this vegetal source of protein as a suitable substitute to FM.S

Evaluating dietary supply of microminerals as a premix in a complete plant ingredient-based diet to juvenile rainbow trout (Oncorhynchus mykiss)

Two basal diets M0 and V0 were formulated with marine and plant based ingredient composition. Seven experimental diets were prepared from the two basal diets namely M0, M100, V0, V30, V60, V100 and V150 by incorporating different levels of a micromineral premix (Cu, Fe, Mn, Se and Zn). Triplicate groups of rainbow trout (initial weight: 20 g) reared at 17°C were fed one of each diet to apparent visual satiation over 12 weeks. Among the V diet fed fish, growth and feed intake exhibited maximal response at V60 level of premix inclusion; Apparent availability coefficient of Fe, Cu and Zn decreased linearly with increasing level of premix whereas apparent availability coefficient of Mn and Se was unaffected. The available dietary concentration in basal V0 diet was for Fe, 20.6; Cu, 2.8; Mn, 6.5; Zn, 17.3 and Se, 0.195 (in mg/kg DM) and in the M0 diet for Fe, 63.3; Cu, 5.2; Mn, 2.9; Zn, 35.2 and Se, 0.87 (in mg/kg DM). In reference to NRC (Nutrient requirements of fish and shrimp. Washington, DC: National Research Council, The National Academies Press, 2011) recommendations, the V0 basal diet accounted for 34.3%, 92.9%, 53.9%, 115% and 130.2% and the contribution from M0 diet for 105.5%, 173.3%, 24.2%, 234.7% and 580% of the minimal dietary inclusion levels of Fe, Cu, Mn, Zn and Se to rainbow trout, respectively. However, data on whole body mineral contents showed that normal levels were maintained only for Cu and Mn through supply from basal V0 diet. For Zn and Se, available supply even from the highest supplemented diet (V150) was not sufficient to maintain normal body mineral levels of rainbow trout in the present study. On the whole, optimal dietary inclusion levels of microminerals are altered while using fishmeal-free diets for rainbow trout

Chapter 6. Skeletal Anomalies in Reared European Fish Larvae and Juveniles. Part 1: Normal and Anomalous Skeletogenic Processes

The successful production of good quality larvae is a vital element for the success and commercial stability of the fish farming industry. This important new book reviews our current understanding of larval biology, including how external (environmental and nutritional) and internal (molecular/ developmental/ physiological/ behavioral/ genetic) factors interact in defining the phenotype and quality of fish larvae and juveniles. The detailed coverage within Success Factors for Fish Larval Production includes broodstock genetics and husbandry, water quality, larval nutrition and feeding, growth physiology, health, metamorphosis, underlying molecular mechanisms for development, larval behavior and environmental conditions. The book also discusses the research needs and the available tools to: improve egg quality and larval production via broodstock management and nutrition control the phenotype of juveniles and table-size fish via manipulations of the conditions of larval rearing (phenotypic plasticity); reduce high mortality in fish larvae control the growth rate independent of a larval batch overcome the limited digestive capacity in first feeding larvae optimize diet composition, formulation and technology minimize skeletal abnormalities, improve disease and stress resistance in fish larvae. Success Factors for Fish Larval Production also reviews research and commercially applicable larval quality indicators and predictors, including their integration into IT-based prediction matrices. This book will be of great use and interest to fish biologists, developmental biologists, physiologists and zoologists. All those working in fish aquaculture facilities and hatcheries will find much of great interest and commercial use within this book. All libraries in universities and research establishments where biological sciences, aquaculture and fisheries are studied and taught should have copies of this book on their shelves