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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Species Identification of 3 Hypsibarbus spp. (Pisces: Cyprinidae) Using PCR–RFLP of Cytochrome b Gene) ผู้เขียน: ดร.พัฒนี จันทรโรทัย, รองศาสตราจารย์ , สุรภพ สุทธิวิเศษ, Wongpathom Kamonrat, สุรินทร์ ปิยะโชคณากุล, Chavalit Vidthayanon สื่อสิ่งพิมพ์:pdf AbstractPolymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) was used to identify 3 closely related Hypsibarbus spp: Hypsibarbus wetmorei, H. vernayi, and H. malcolmi. Mitochondrial cytochrome b gene (993 bp) in 3 Hypsibarbus spp. showed single PCR– product. The sequencing results of PCR–products in 3 Hypsibarbus spp. showed very low interspecific variation. However it could be used to discriminate these species by RFLP analysis. The combination of 2 restriction enzymes; Bsp143I and BcuI were used to identify 3 Hypsibarbus spp. Bsp143I could discriminate H. vernayi from H. wetmorei and H. malcolmi, by generating 3 fragments (535 bp, 234 bp and 224 bp) in H. vernayi whereas 2 fragments of 769 bp and 224 bp in H. wetmorei and H. malcolmi. Thereafter, BcuI was effectively discriminated H. wetmorei from H. malcolmi by generating 3 fragments (591 bp, 288 bp and 114 bp) in H. malcolmi and uncut fragment in H. wetmorei. There were intraspecific restriction polymorphism in H. vernayi using BcuI which generated 2 patterns; an uncut fragment and 2 fragment of approximately 700 bp and 300 bp. Thus, PCR–RFLP technique could be used to identify 3 closely related Hypsibarbus spp. |
 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Genetic and Morphological Variation among Hatchery Stocks of Thai Silver Barb Barbonymus gonionotus (Bleeker, 1850)) ผู้เขียน: Santi Pannusa, ดร.สุภาวดี พุ่มพวง, ศาสตราจารย์ , Wongpathom Kamonrat สื่อสิ่งพิมพ์:pdf AbstractMicrosatellite loci and truss morphometrics were used to discriminate eight hatchery stocks of silver barb (Barbonymus gonionotus) in Northeast Thailand. The results showed significant genetic (P < 0.0017) and morphological differences (P < 0.0017) in 18 and 25 out of 28 pair-wise comparisons, respectively. However, cluster analyses revealed a weak association between genetic differentiation and morphometric variation. Principal components analysis identified three truss measurements in the abdominal regions as the most powerful variables to distinguish stocks. Discriminant function analysis, based on 13 truss elements, assigned individuals to four distinct groups, and one group consisted of samples from four stocks. Among distinct stocks that showed variation in body shape, the Buri Ram samples displayed the largest body size as a result of breeding selection. The identity of a stock could be constructed from three measurements for body shape that were significantly correlated. Findings demonstrated the use of the truss morphometric approach in discriminating different hatchery stocks of silver barb within the studied stations. |
 หัวเรื่อง:การทดสอบปลาไนฮังการีลูกผสม (P-31) เพื่อการผลิตสายพ่อแม่พันธุ์รุ่นที่ 2 ผู้เขียน: Wongpathom Kamonrat, Surang Summanojitraporn, Amornwit Oonjanohm, Surin Apirak สื่อสิ่งพิมพ์:pdf AbstractA breeding experiment was set to produce the pure lines of scaled and mirror carp from the Hungarian hybrid (P-31) introduced from Fisheries Research Institute of Hungary. The two lines will be used to produce a second generation of the Hungarian hybrid to be used for aquaculture production. The experiment was carried out during 1989 to 1996 at the National Aquaculture Genetics Research Institute?s Strain Testing Unit in Phitsanulok and Khonkaen provinces. The procedures included the breeding of P-31 and a test cross of its phenotypically scaled F1 offspring with a scattered mirror carp, which was also its F1 offspring. Although the test cross procedure is strait- forward, it is time consuming, laborious and facility demanding. The result from this experiment indicated a noticeable shape differences among the scaled phenotype offspring of P-31. The shape differences were confirmed and linked, to some degree, with their genotypes controlling scale appearances using a truss network method and principal components analysis. The finding suggested that by selecting a certain shape of fish before subjecting to a test cross procedure would improve the probability of obtaining the pure line scaled carp from the scaled phenotype offspring of the P-31. |
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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Microsatellite Markers Suggested Moderate Genetic Variation in Indian Mackerel (Rastrelliger kanagurta) Populations from the Andaman Sea, Thailand) ผู้เขียน: Nut Munpholsri, ดร.สุภาวดี พุ่มพวง, ศาสตราจารย์ , Wansuk Senanan, Wongpathom Kamonrat สื่อสิ่งพิมพ์:pdf AbstractThe Indian mackerel (Rastrelliger kanagurta) fi shery in Thailand has experienced declining catches during the past several years and was identifi ed as over-exploited. The study obtained population genetic information to support the ongoing management of the fi shery. Six microsatellite loci from short mackerel (Rastrelliger brachysoma) were screened to assess the genetic diversity in Indian mackerel stocks from four localities on the Andaman Sea coast. All population samples exhibited similar and moderate genetic variation with an average of 6.5 to 7.8 alleles per locus and average expected heterozygosity at all loci of 0.60 to 0.69. There was no evidence to support population substructure (overall genetic differentiation = FST = 0.012; non-signifi cant pairwise FST values). Gene fl ow was detected through the presence of rare alleles at three loci across samples. The contemporary estimated effective population size was approximately 330 if a single stock unit was considered. This moderate size of the breeding population is crucial for the short-term conservation of genetic variability in Indian mackerel stocks. Genetic data from the present study provides baseline genetic information and supports the management of Indian mackerel as a single unit. |
 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of Warm Temperatures on Ovarian Development of Walking Catfi sh Clarias macrocephalus (G?nther, 1864) During Post-Spawning Season) ผู้เขียน: พรพรรณ พุ่มพวง, ดร.สุภาวดี พุ่มพวง, ศาสตราจารย์ , Wongpathom Kamonrat สื่อสิ่งพิมพ์:pdf AbstractThis study aimed to determine the possibility of using temperature manipulation to stimulate ovarian activities of Clarias macrocephalus during the post-spawning season. The ovarian development and monthly change in the gonado-somatic index (GSI) of females held under pond conditions was monitored over a 1 yr period from April 2008 to March 2009. In October, 13 mth-old female fi sh (weight ? SD= 108 ? 12.7 g) were randomly collected from an earthen pond and exposed to different temperatures at 25, 30 and 35 ?C under hatchery conditions for 6 wk. The results indicated that the change in the GSI appeared to be correlated with the amount of rainfall, but not to the variation in seasonal temperature. A signifi cant (P < 0.05) variation of mean GSI values was observed among months with the highest value ? SE (13.91 ? 3.63%) in July. Histological examination of ovaries revealed that in females held under 25, 30 and 35 ?C, the number of vitellogenic oocytes progressively increased from 0.5–4.7% at week 2 to 4.6–19.7% at week 6, whereas in females held in the earthen pond, ovaries contained only immature oocytes. Exposure to warm temperatures resulted in signifi cant elevations of plasma cortisol but not glucose concentrations. Although fully matured females could not be obtained, the present study suggested that temperature manipulation was probably the practical way to increase the number of maturing females during the off reproductive season for walking catfi sh. |
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