The major histocompatability complex (MHC) is a multigene family of receptors that bind and present antigenic peptides to T‐cells. Genes of the MHC are characterized by an outstanding genetic polymorphism, which is considered to be maintained by positive selection. Sites involved in peptide binding form binding pockets (P) that are collectively termed the peptide‐binding region (PBR). In this study, we examined the level of MH...

Sensitivity of skeletal ontogenesis to temperature was assessed in Mozambican tilapia Oreochromis mossambicus and culture temperature manipulations (22, 27 and 32° C) were used to establish if age or length gave the most suitable metric for standardization. Oreochromis mossambicus larval growth was composed of two growth stanzas: an initial period of rapid growth, followed by a slower growth phase. Irrespective of culture temp...

Analysis of the genetic structure of the Norway lobster ( Nephrops norvegicus ), a marine crustacean with high commercial value, was undertaken to gain information regarding the differentiation of Atlantic from Mediterranean populations of marine invertebrates. Restriction fragment length polymorphism analysis of two mitochondrial DNA segments, 3.6 kilobases in total, was performed. Twelve populations from the North Sea, Irish...

The development and severity of fin damage was examined in groups of juvenile rainbow trout Oncorhynchus mykiss of different strength of feeding hierarchies. The development of dorsal and caudal fin damage over time was compared between four groups fed different ration levels (0·25, 0·5, 1·0 and 1·5% body weight day −1 ) and between individuals of different feeding rank within each group. Dominance hierarchies were assessed fr...