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Association mapping of early mortality syndrome (EMS)-acute hepatopancreatic necrosis disease (AHPND) tolerance in Pacific white shrimp |
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| รหัสดีโอไอ | |
| Title | Association mapping of early mortality syndrome (EMS)-acute hepatopancreatic necrosis disease (AHPND) tolerance in Pacific white shrimp |
| Creator | Anong Nimlamai |
| Contributor | Kittipat Ukotkij, Advisor |
| Publisher | Thammasat University |
| Publication Year | 2568 |
| Keyword | Association mapping, EMS-AHPND tolerance, Genotyping-by sequencing, Microsatellite, Pacific white shrimp, Single nucleotide polymorphisms |
| Abstract | The Pacific white shrimp (Litopenaeus vannamei (Boone, 1931)) is a key aquaculture species in Thailand with substantial economic importance. Ensuring genetic diversity is critical for sustaining a robust gene pool in farmed populations, ensuring resilience to diseases, environmental changes, and enhancing overall productivity. In the present study, genetic variation and population structure across 35 families of fourth-generation selective breeding lines of L. vannamei were monitored using five microsatellite DNA markers. The polymorphism information content (PIC) all microsatellite loci showed high polymorphism , with PIC greater than 0.70, indicating that the DNA markers were highly informative and effective in detecting allele variations in this population. The number of alleles per locus and the number of effective alleles (Ne) ranged from 3 to 6 and 2.809 to 4.598, with averages of 4.4 and 3.734, respectively. These values indicate that the population possessed a moderate level of genetic diversity. Overall average of observed heterozygosity (Ho) ranged from 0.209 to 0.492, a value below the expected heterozygosity (He) (0.714-0.784). The mean inbreeding (Fis) coefficient across all loci was 0.336 suggesting a moderate degree of inbreeding in this population. The population structure analysis showed that the 35 families were classified into two subpopulations (K=2), related to the sources of the base population collected from two private hatcheries. This study will offer important insights into population genetics and help guide breeding strategies of L. vannamei.Early Mortality Syndrome (EMS)-Acute Hepatopancreatic Necrosis Disease (AHPND) is a severe bacterial disease that significantly impacts L. vannamei farming, leading to substantial declines in shrimp production. To mitigate losses caused by EMS-AHPND, molecular breeding presents a promising approach for sustainable disease prevention. This study was directed toward the identification of SNP markers associated with EMS-AHPND tolerances using Genotyping-by sequencing (GBS). SNP markers were identified in fourth-generation selective breeding lines of L. vannamei. A total of 9,504 filtered SNPs were analyzed for their association with EMS-AHPND tolerances using the Fixed and Random Model Circulating Probability Unification (FarmCPU), accounting for population stratification and cryptic relatedness. Seven SNPs were identified as significantly associated with EMS-AHPND tolerances, with P-values passing the Bonferroni-adjusted threshold. This study provides a valuable genetic tool for the genetic improvement of EMS-AHPND tolerance in L. vannamei. |
