Developmental stability and genetic heterozygosity in wild and cultured stocks of gilthead sea bream (Sparus aurata)

2001 ◽  
Vol 81 (2) ◽  
pp. 283-288 ◽  
Author(s):  
J. Palma ◽  
J.A. Alarcon ◽  
C. Alvarez ◽  
E. Zouros ◽  
A. Magoulas ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Fluctuating Asymmetry ◽  
Dna Analysis ◽  
Sparus Aurata ◽  
Branchial Arch ◽  
Developmental Stability ◽  
Distinct Pattern ◽  
Sea Bream ◽  
In The Wild ◽  
The Right

The present study checks on the validity of the hypothesis that heterozygosity and the fluctuating asymmetry (FA), common measure of the developmental stability, are linked in populations of wild and cultured stocks of Sparus aurata from five countries. Muscle and liver samples were analysed for variation in 26 allozymes and three microsatellite loci. Pectoral fin rays and upper and lower gill rakers of the first branchial arch were counted on the left and on the right sides of each fish. Fluctuating asymmetry existed in the majority of the samples although their values were consistently low, (0·305±0·147), but higher in the cultured samples. The allozyme heterozygosity values were always high, but lower in the cultured samples. The microsatellite DNA analysis produced similar results. Heterozygosity was higher in cultured individuals (except for the Greek samples). These findings seem to be early evidence that the reared samples are losing some genetic variation, especially due to the loss of the rarest alleles (which were present in the wild populations). Genetic drift, probably caused by propagation practices, is most likely responsible for the decrease of the genetic variation. No distinct pattern of geographic separation was identified.

scholarly journals Genome-wide analysis clarifies the population genetic structure of wild Gilthead Sea Bream (Sparus aurata)

2020 ◽  
Author(s):  
Francesco Maroso ◽  
Konstantinos Gkagkavouzis ◽  
Sabina De Innocentiis ◽  
Jasmien Hillen ◽  
Fernanda do Prado ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Sparus Aurata ◽  
Snp Markers ◽  
Gilthead Sea Bream ◽  
Sea Bream ◽  
Commercial Fishing ◽  
North East ◽  
The North ◽  
In The Wild ◽  
The Mediterranean

AbstractGilthead sea bream is an important target for both recreational and commercial fishing in Europe, where it is also one of the most important cultured fish. Its distribution range goes from the Mediterranean to the African and European coasts of the North-East Atlantic. So far, the genetic structure of this species in the wild has been studied with microsatellite DNA, but the pattern of differentiation could not be fully clarified. In this study, almost 1000 wild sea bream from 23 locations in the Mediterranean Sea and Atlantic ocean where genotyped at 1159 SNP markers, of which 18 potentially under selection. Neutral markers suggested the presence of a weak subdivision into three genetic clusters: Atlantic, West and East Mediterranean. This last group could be further subdivided into an Ionian/Adriatic and an Aegean group using outlier markers. Seascape analysis suggested that this differentiation was mainly due to difference in salinity, and this was also supported by preliminary genomic functional analysis. These results are of fundamental importance for the development of proper management of this species in the wild and are a first step toward the study of the potential genetic impact of the sea bream aquaculture industry.

scholarly journals Genetic Variation, GWAS and Accuracy of Prediction for Host Resistance to Sparicotyle chrysophrii in Farmed Gilthead Sea Bream (Sparus aurata)

2020 ◽  
Vol 11 ◽  
Author(s):  
Muhammad Luqman Aslam ◽  
Roberta Carraro ◽  
Anna Kristina Sonesson ◽  
Theodorus Meuwissen ◽  
Costas S. Tsigenopoulos ◽  
...  
Keyword(s):  
Body Weight ◽  
Genetic Variation ◽  
Host Resistance ◽  
Sparus Aurata ◽  
Challenge Test ◽  
Gilthead Sea Bream ◽  
Sea Bream ◽  
Genomic Information ◽  
Parasite Count ◽  
Accuracy Of Prediction

Gilthead sea bream (Sparus aurata) belongs to a group of teleost which has high importance in Mediterranean aquaculture industry. However, industrial production is increasingly compromised by an elevated outbreak of diseases in sea cages, especially a disease caused by monogeneans parasite Sparicotyle chrysophrii. This parasite mainly colonizes gill tissues of host and causes considerable economical losses with mortality and reduction in growth. The aim of current study was to explore the genetics of host resistance against S. chrysophrii and investigate the potential for genomic selection to possibly accelerate genetic progress. To achieve the desired goals, a test population derived from the breeding nucleus of Andromeda Group was produced. This experimental population was established by crossing of parents mated in partial factorial crosses of ∼8 × 8 using 58 sires and 62 dams. The progeny obtained from this mating design was challenged with S. chrysophrii using a controllable cohabitation infection model. At the end of the challenge, fish were recorded for parasite count, and all the recorded fish were tissue sampled for genotyping by sequencing using 2b-RAD methodology. The initial (before challenge test) and the final body weight (after challenge test) of the fish were also recorded. The results obtained through the analysis of phenotypic records (n = 615) and the genotypic data (n = 841, 724 offspring and 117 parents) revealed that the resistance against this parasite is lowly heritable (h2 = 0.147 with pedigree and 0.137 with genomic information). We observed moderately favorable genetic correlation (Rg = −0.549 to −0.807) between production traits (i.e., body weight and specific growth rate) and parasite count, which signals a possibility of indirect selection. A locus at linkage group 17 was identified that surpassed chromosome-wide Bonferroni threshold which explained 22.68% of the total genetic variance, and might be playing role in producing genetic variation. The accuracy of prediction was improved by 8% with genomic information compared to pedigree.

Genetic variation in farmed populations of the gilthead sea bream Sparus aurata in Greece using microsatellite DNA markers

2011 ◽  
Vol 43 (2) ◽  
pp. 239-246 ◽  
Author(s):  
Dimitrios Loukovitis ◽  
Elena Sarropoulou ◽  
Emmanouella Vogiatzi ◽  
Costas S. Tsigenopoulos ◽  
Georgios Kotoulas ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Dna Markers ◽  
Microsatellite Dna ◽  
Sparus Aurata ◽  
Gilthead Sea Bream ◽  
Sea Bream ◽  
Microsatellite Dna Markers

scholarly journals Mitochondrial DNA analysis reveals extremely low genetic diversity in a managed population of the Critically Endangered Gharial (Gavialis gangeticus, Gmelin, 1789)

2020 ◽  
pp. 202-206
Author(s):  
Surya Prasad Sharma
Keyword(s):  
Genetic Variation ◽  
Control Region ◽  
Dna Analysis ◽  
Critically Endangered ◽  
Mt Dna ◽  
Low Level ◽  
Low Genetic Diversity ◽  
In The Wild ◽  
Gavialis Gangeticus ◽  
Genetic Assessment

A decline in the numbers of threatened species is often reversed by reintroduction with the aim of repopulating or strengthening the population to reduce the risk of extinction. The success of reintroduction programs is associated with demographic and genetic monitoring of the reintroduced populations. We undertook a genetic assessment of the Critically Endangered gharial (Gavialis gangeticus) to assess the current level of genetic variation using three partial mitochondrial (mt) DNA regions: cytochrome b, cytochrome c oxidase subunit-I and the control region. We sequenced 103 samples collected across 14 nesting sites. A low level of mtDNA variation was observed in the sampled population (hd = 0.462 ± 0.048; Pi = 0.00029 ± 0.00004). Only five distinct haplotypes were observed in three segregating sites. This is the first assessment of the genetic variation in the wild gharial population to be made using mtDNA. Homogeneity in the 520 bp hypervariable control region of the crocodilian mtDNA is reported here for the first time. The low mitochondrial diversity and no genetic structure in the sampled population is indicative of a genetic bottleneck, the founder effect and probably associated with humanassisted augmentation of the population of the gharial. An extremely low level of genetic variation in the largest gharial population highlights the vulnerability of the gharial population in the wild and calls for immediate genetic assessment of other gharial populations so that a robust conservation plan focusing on connectivity and enhanced protection can be developed for the long-term persistence of the gharial in the wild.

scholarly journals Loss of genetic variation in Greek hatchery populations of the European sea bass (Dicentrarchus labrax L.) as revealed by microsatellite DNA analysis

2014 ◽  
Vol 16 (1) ◽  
pp. 197 ◽  
Author(s):  
D. LOUKOVITIS ◽  
B. IOANNIDI ◽  
D. CHATZIPLIS ◽  
G. KOTOULAS ◽  
A. MAGOULAS ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Microsatellite Dna ◽  
Dna Analysis ◽  
Natural Populations ◽  
Dicentrarchus Labrax ◽  
Sea Bass ◽  
European Sea Bass ◽  
Allele Number ◽  
In The Wild ◽  
Breeding Programmes

Genetic variation in four reared stocks of European sea bass Dicentrarchus labrax L., originating from Greek commercial farms, was assessed using five polymorphic microsatellite markers and was compared with that of three natural populations from Greece and France. The total number of alleles per marker ranged from 8 to 22 alleles, and hatchery samples showed the same levels of observed heterozygosity with samples from the wild but substantially smaller allelic richness and expected heterozygosity. The genetic differentiation of cultivated samples between them as well as from the wild origin fish was significant as indicated by Fst analysis. All population pairwise comparisons were statistically significant, except for the pair of the two natural Greek populations. Results of microsatellite DNA analysis herein showed a 37 % reduction of the mean allele number in the hatchery samples compared to the wild ones, suggesting random genetic drift and inbreeding events operating in the hatcheries. Knowledge of the genetic variation in D. labrax cultured populations compared with that in the wild ones is essential for setting up appropriate guidelines for proper monitoring and management of the stocks either under traditional practices or for the implementation of selective breeding programmes.

Stress effects of amyloodiniosis in gilthead sea bream Sparus aurata

2018 ◽  
Vol 127 (3) ◽  
pp. 201-211 ◽  
Author(s):  
M Moreira ◽  
M Herrera ◽  
P Pousão-Ferreira ◽  
JI Navas Triano ◽  
F Soares
Keyword(s):  
Sparus Aurata ◽  
Gilthead Sea Bream ◽  
Sea Bream ◽  
Stress Effects

scholarly journals Branchial Cyst in the Parapharyngeal Space: A Case Report

2021 ◽  
pp. 1-4
Author(s):  
Iyad Said Hamadi ◽  
Lubna Lutfi ◽  
Asma Anan Mohammed ◽  
Zahr Alkhadem
Keyword(s):  
Branchial Arch ◽  
External Carotid Artery ◽  
Cystic Mass ◽  
External Carotid ◽  
Lateral Side ◽  
Branchial Cyst ◽  
Embryonic Life ◽  
Branchial Cleft ◽  
The Right

Branchial cleft cysts are congenital anomalies that most commonly arise from a failure of fusion of the second branchial arch during embryonic life. They usually present as a swelling in the lateral side of the neck, below the mandible. In this article, we present a case of a 28-year-old female patient with a right branchial cyst measuring 7 × 6 × 5 cm, who presented with an asymptomatic, rapidly growing mass in the right anterior triangle of the neck that abutted the right external carotid artery, leading to stenosis of the vessel that is preceded by dilatation above the site of compression. She underwent excision of the cystic mass with preservation of the facial nerve and presented no active complaints on follow-up a few weeks postoperatively.

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