Quantitative genetic properties of four measures of deformity in yellowtail kingfish Seriola lalandi Valenciennes, 1833

Abstract

The main aim of this study was to estimate the heritability for four measures of deformity and their genetic associations with growth (body weight and length), carcass (fillet weight and yield) and flesh-quality (fillet fat content) traits in yellowtail kingfish Seriola lalandi. The observed major deformities included lower jaw, nasal erosion, deformed operculum and skinny fish on 480 individuals from 22 families at Clean Seas Tuna Ltd. They were typically recorded as binary traits (presence or absence) and were analysed separately by both threshold generalized models and standard animal mixed models. Consistency of the models was evaluated by calculating simple Pearson correlation of breeding values of full-sib families for jaw deformity. Genetic and phenotypic correlations among traits were estimated using a multitrait linear mixed model in ASReml. Both threshold and linear mixed model analysis showed that there is additive genetic variation in the four measures of deformity, with the estimates of heritability obtained from the former (threshold) models on liability scale ranging from 0.14 to 0.66 (SE 0.32-0.56) and from the latter (linear animal and sire) models on original (observed) scale, 0.01-0.23 (SE 0.03-0.16). When the estimates on the underlying liability were transformed to the observed scale (0, 1), they were generally consistent between threshold and linear mixed models. Phenotypic correlations among deformity traits were weak (close to zero). The genetic correlations among deformity traits were not significantly different from zero. Body weight and fillet carcass showed significant positive genetic correlations with jaw deformity (0.75 and 0.95, respectively). Genetic correlation between body weight and operculum was negative (-0.51, P < 0.05). The genetic correlations' estimates of body and carcass traits with other deformity were not significant due to their relatively high standard errors. Our results showed that there are prospects for genetic selection to improve deformity in yellowtail kingfish and that measures of deformity should be included in the recording scheme, breeding objectives and selection index in practical selective breeding programmes due to the antagonistic genetic correlations of deformed jaws with body and carcass performance.

Does selection in a challenging environment produce Nile tilapia genotypes that can thrive in a range of production systems?

“…Due to the very low proportion of animals that had deformity (0.15%) and ‘pale’ gill condition (0.016%) in this population, the heritability for these traits are not significantly different from zero, indicating that continuing collection of the data in future generations is needed in order to obtain reliable estimates for binary characteristics. Other studies show existence of useful additive genetic component for a range of deformity measures but the heritability for these traits was low to moderate and associated with high standard errors: 0.16–0.29 in European sea bass Dicentrarchus labrax 40 and Yellowtail kingfish Seriola lalandi 41 .…”

“…However, selection experiments for high production performance in aquatic animals generally showed both negative 54 55 and positive 23 53 56 effects on maturation. In a long term, a multi-trait selection approach using a desired gain (or restricted) index, as demonstrated in kingfish 41 , can improve traits showing antagonistic genetic correlations.…”

Genetic improvement for important farmed aquaculture species with a reference to carp, tilapia and prawns in Asia: achievements, lessons and challenges

“…Under these situations, a desired gain selection index approach can be used to simultaneously improve traits as demonstrated in yellowtail kingfish Seriola lalandi, Valenciennes (Nguyen et al . ). In conclusion, it is recommended that economically important traits should be included in the recording scheme, breeding objective and selection index to ensure the sustainability of long‐term genetic improvement programmes for aquaculture species.…”

Prevalence of deformities in intensively reared peled Coregonus peled and comparative morphometry with pond‐reared fish

“…Skeletal and opercular deformities, often reported in fish reared in intensive systems, can seriously affect efficient culture (Koumoundouros, Oran, Divanach, Stefanakis, & Kentouri, ; Policar et al., ), negatively affecting fish physiology and welfare, growth performance, and quality and value of product (Fjelldal et al., ). The aetiology, frequency of occurrence and biological significance of deformities vary among fish species (Chin, Loh, Hong, & Gibson‐Kueh, ; Georgakopoulou, Katharios, Divanach, & Koumoundouros, ; Lü et al., ; Nguyen, Whatmore, Miller, & Knibb, ). The aim of this study was to record the frequency of vertebral, opercular and fin deformities in intensively reared peled Coregonus peled (Gmelin 1879).…”