Swimming is an integral part of the life history of many fish species as is intimately linked with their ability to express feeding and predator avoidance behaviors, habitat selection and environmental preferences, social and reproductive behaviors as well as migratory behaviors. Therefore, swimming is an important determinant factor of fitness in a true Darwinian sense and, not surprisingly, swimming performance has been often used as a measure of physiological fitness in fish. The main aim of this Research Topic is to showcase some of the current studies designed to improve our understanding of the physiological energetic and metabolic requirements of swimming and of the adaptive responses to swimming in fish.

Traditionally, behaviour and physiology have been considered two separate fields of biology with the majority of available literature focusing on one or the other. Recently the need for a multidisciplinary approach to these topics has been realised, highlighted by some of the sessions to be held at the 2003 annual meeting of the Society for Integrative and Comparative Biology such as 'regulation of behaviour' and 'mechanisms of behaviour'. The proposed volume aims to bring together these disciplines in a comprehensive review of the available literature. Fish Physiology: Behaviour and Physiology of Fish will be novel in actively bridging these two areas of fish biology together and considering them as inextricably linked. The progression of chapters focuses on different aspects of the life history of a fish, from predator avoidance through to reproduction, each written by scientists currently bridging the gap between behaviour and physiology in their own specialised subdiscipline. Multidisciplinary and integrative research in fish biology Written by internationally recognized researchers Encompasses the whole life span of fish A wide variety of inter-related topics presented in a cohesive format

From a global perspective aquaculture is an activity related to food production with large potential for growth. Considering a continuously growing population, the efficiency and sustainability of this activity will be crucial to meet the needs of protein for human consumption in the near future. However, for continuous enhancement of the culture of both fish and shellfish there are still challenges to overcome, mostly related to the biology of the cultured species and their interaction with (increasingly changing) environmental factors. Examples of these challenges include early sexual maturation, feed meal replacement, immune response to infectious diseases and parasites, and temperature and salinity tolerance. Moreover, it is estimated that less than 10% of the total aquaculture production in the world is based on populations genetically improved by means of artificial selection. Thus, there is considerable room for implementing breeding schemes aimed at improving productive traits having significant economic impact. By far the most economically relevant trait is growth rate, which can be efficiently improved by conventional genetic selection (i.e. based on breeding values of selection candidates). However, there are other important traits that cannot be measured directly on selection candidates, such as resistance against infectious and parasitic agents and carcass quality traits (e.g. fillet yield and meat color). However, these traits can be more efficiently improved using molecular tools to assist breeding programs by means of marker-assisted selection, using a few markers explaining a high proportion of the trait variation, or genomic selection, using thousands of markers to estimate genomic breeding values. The development and implementation of new technologies applied to molecular biology and genomics, such as next-generation sequencing methods and high-throughput genotyping platforms, are allowing the rapid increase of availability of genomic resources in aquaculture species. These resources will provide powerful tools to the research community and will aid in the determination of the genetic factors involved in several biological aspects of aquaculture species. In this regard, it is important to establish discussion in terms of which strategies will be more efficient to solve the primary challenges that are affecting aquaculture systems around the world. The main objective of this Research Topic is to provide a forum to communicate recent research and implementation strategies in the use of genomics in aquaculture species with emphasis on (1) a better understanding of fish and shellfish biological processes having considerable impact on aquaculture systems; and (2) the efficient incorporation of molecular information into breeding programs to accelerate genetic progress of economically relevant traits.

The genetic improvement of fish for aquaculture and related fisheries has seen huge advances over recent years. Building upon the previous two editions of Aquaculture and Fisheries Biotechnology: Genetic Approaches, this 3rd edition offers a presentation of traditional selective breeding, modern genetic biotechnology, genomics, gene transfer and gene editing, and the latest developments in genetic biotechnology such as epigenetics, xenogenesis and genome-wide association study coupled with commercial application, the impact of government regulation and expectations for the future. It provides a firm grounding in relevant aspects of classical genetics, before focusing on particular aspects such as sex reversal and breeding as applied in aquaculture and fisheries. It also explores how more recent molecular genetics, genomics and biotechnology techniques can be used and combined in improvement programmes for fish and aquaculture species. A glossary explains the latest terminology used in biotechnology and genetics. This book will be useful for research scientists and students in marine biotechnology, aquaculture biotechnology, and fish genetics and breeding.