First steps on technological and genetic improvement of European abalone (<i>Haliotis tuberculata</i>) based on investigations in full-sib families

Abstract

The European abalone Haliotis tuberculata is of economical importance in Europe, and recently in France where most of the consumed abalones remained wild animals fished on the coast. Recently, the creation of hatcheries allowed the production of cultured animals, and aquaculture is in progress. To optimize selective breeding programs, different studies were performed on adults and on their progenies. First, ten adult families, assumed to be bi-parental and produced in 2007 were analyzed. As these families were developed at the beginning of the hatchery production, the parentage of the individual necessitated to be tested. The progenies parentage assignment was done by using eight microsatellite DNA loci. In fine, the heritability was estimated from the analysis of variance of seven full-sib families which include from 23 to 27 progenies. Heritability estimate was the higher for length, width and weight (0.37, 0.29 and 0.40 respectively). A high correlation was also shown between these heritable traits which can be useful during animal breeding. Shell color traits were also analyzed, using image treatment procedure. Two traits were selected according to the global color of the shell: red color and hue. The distribution of these traits evidenced a polygenic genetic control of shell color and measure of heritability evidenced a high to medium value for red color (Cr) and Hue (H) (0.33 and 0.20 respectively). No correlation was shown between growth and this parameter. In a second time, juveniles families produced in 2010 were studied from parents issued of the first selection. A correlation between size and density at juvenile stage was established but a statistical analysis demonstrated, by using density as co-variable a significant effect of family on size. In these conditions, growth is highly heritable (0.74). This study is a first step toward the use of genetic markers for selection, but also a step toward the breeding improvement of European abalone.

Anti-predator response of Haliotis tuberculata is modified after only one generation of domestication

“…Numerous studies have shown that growth is a heritable trait in Haliotis spp. (Lucas et al 2006, Robinson et al 2013, Roussel et al 2013, Camara & Symonds 2014, Brokordt et al 2015, although the estimation of heritability varies widely among species and for the same species. Neverthe-less, improved growth of the F 1 generation is not always observed in spite of the fact that growth in weight is a heritable trait.…”

Seasonal and diurnal variability in carbon respiration, calcification and excretion rates of the abalone Haliotis tuberculata L.

“…Nonetheless, the natural variations (day–night and season cycles) in the metabolism of abalone from the natural habitat and the effect of body size upon respiratory rates in mature individuals (i.e. size over 50 mm, Hayashi, 1980a), are still not well understood and represent important biological information for the recently developed industry in Europe (Roussel et al , 2013; Cook, 2014; Lachambre et al , 2017). Indeed, many abalone farms rely on coastal seawater and hence factors such as seawater temperature or dissolved oxygen, which vary according to season, day–night and tidal cycles, are likely to impact abalone physiology (Morash & Alter, 2015).…”