Scophthalmus Maximus L. (scophthalmus + maximu_l)

Distribution by Scientific Domains

Selected Abstracts

A suite of highly polymorphic microsatellite markers in turbot (Scophthalmus maximus L.) with potential for use across several flatfish species

A. Iyengar

Influence of several non-nutrient additives on nonspecific immunity and growth of juvenile turbot, Scophthalmus maximus L.

Abstract The effects of three non-nutrient additives on nonspecific immunity and growth of juvenile turbot (Scophthalmus maximus L.) were studied in this feeding experiment. The five treatments are basal diet alone, basal diets containing three different additives [0.4 g kg,1 of xylo-oligosaccharides (XOS), 1.3 g kg ,1 of yeast cell wall and 0.8 g kg ,1 of bile acids] individually or in combination. Two hundred and twenty-five turbots (average initial weight 151.3 11.3 g) were randomly allotted in five treatments with three replicates within each treatment in a 72-day period. Comparing with basal diet group, activities of C3, C4, phagocyte, lysozyme, specific growth rate and feed conversion rate in yeast cell wall, XOS and the combined groups was enhanced significantly (P < 0.05); however, these parameters in bile acid groups were increased slightly (P > 0.05) except for phagocyte (P < 0.05); superoxide dismutase activity in additive groups was not significantly increased (P > 0.05) except for the combined group (P < 0.05). In conclusion, supplementation of yeast cell wall and XOS enhanced the nonspecific immunity of juvenile turbot. Synergistic or additive effect of the three additives was not observed. [source]

Effect of feed restriction on the growth performance of turbot (Scophthalmus maximus L.) juveniles under commercial rearing conditions

Isidro Blanquet
Abstract Two trials were performed to study the effect of periodic feed deprivation (trial 1) or feed restriction, followed by satiation feeding (trial 2) on the growth performance of turbot juveniles under commercial rearing conditions. In trial 1, duplicate groups of 350 fish with an initial weight of 62 g were fed a commercial diet to apparent visual satiation for 7, 6, 5 or 4 days a week for 83 days. At the end of the trial, fish weight was directly related to the number of feeding days but feed efficiency and protein efficiency ratio were not affected by treatments. At the end of the trial, there were no differences in whole-body composition among groups. In trial 2, duplicate groups of 500 fish with an initial weight of 33 g were fed a commercial diet to satiation (100%) or feed restricted to 90%, 80% and 70% of satiation for 90 days. Thereafter, all groups were fed to satiation for 34 days. During the feed restriction period, growth was directly related to feed intake, while during the satiation feeding period, it was inversely related to the previous feeding level. At the end of the trial, the final weight was not different among groups. At the end of the feed restriction period, whole-body lipid content showed a trend to decrease with an increase in the feed restriction level. The results of this study indicate that under practical conditions, turbot juveniles should be fed daily as even cycles of short periods of feed deprivation negatively affect growth, while not improving feed efficiency. On the contrary, even after a relatively long feed restriction period, fish shows compensatory growth, and this may be used as a feed management strategy for controlling fish production in commercial farms. [source]

Statistical properties and performance of pairwise relatedness estimators using turbot (Scophthalmus maximus L.) family data

Ania Pino-Querido
Abstract The statistical properties and performance of four estimators of pairwise relatedness were evaluated in several scenarios using the microsatellite genotype data from a set of large known full-sibships of turbot. All estimators showed a significant negative bias for the four kinships commonly used in these studies (unrelated: UR, half-sibs, full-sibs and parent,offspring), when allele frequencies of the reference population were estimated from the individuals analysed. When these frequencies were obtained from the base population from which all families proceeded, the bias was mostly corrected. The Wang (W) and Li (L) estimators were the least sensitive to this factor, while the Lynch and Ritland (L&R estimator) was the highest one. The error (mean around 0.130) was very similar in all scenarios for W, L and Queller and Goodnight (QG) estimators, while L&R was the highest error-prone estimator. Parent,offspring kinship resulted in the lowest error, when using W, L and QG estimators, while UR resulted in the lowest error with the L&R estimator. Globally, W was the best-performing estimator, although L&R could perform better in specific sampling scenarios. In summary, pairwise estimators represent useful tools for kinship classification in aquaculture broodstock management by applying appropriate thresholds depending on the goals of the analysis. [source]