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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Reproductive Performance and Larval Quality of First and Second Spawning of Pond-Reared Blue Swimming Crab, Portunus pelagicus, Broodstock) ผู้เขียน: ดร.วุฒิชัย อ่อนเอี่ยม , นางสาววาสนา อากรรัตน์ สื่อสิ่งพิมพ์:pdf AbstractThe current was conducted to compare the reproductive performance and larval quality of fi rst (1st) and second (2nd) spawning produced by female blue swimming crab, Portunus pelagicus. The results showed that there were signifi cant differences in several important reproductive parameters and larval quality, 2nd spawning had lower fecundity (508,657 eggs for 1st spawning and 395,118 eggs for 2nd spawning), a lower total number of zoea larvae (259,985 crabs for 1st spawning and 160,900 crabs for 2nd spawning), a lower hatching rate (54.01% for 1st spawning and 41.41% for 2nd spawning) and a lower survival rates of zoea I (87.87% for 1st spawning and 67.19% for 2nd spawning) than 1st spawning. However, the survival rates of the megalopa (30.94% for 1st spawning and 20.29% for 2nd spawning) and fi rst crab stages (1.57% for 1st spawning and 0.85% for 2nd spawning) were not signifi cantly different. Similar crab larval development of 1st and 2nd spawning from the zoea I to megalopa stages (11.2 d for 1st spawning and 11.4 d for 2nd spawning) and the megalopa to fi rst crab stages (4.8 d for 1st spawning and 5.0 d for 2nd spawning) were not signifi cantly different. This study contends that 2nd spawning of female P. pelagicus affected the reproductive performance and survival rates of zoea I. |
 ที่มา:KASETSART UNIVERSITY FISHERIES RESEARCH BULLETINหัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Fecundity Relationship, Maturity Size and Spawning Season of Shark Catfish Helicophagus waandersii Bleeker, 1858 in the Mun River, Thailand) สื่อสิ่งพิมพ์:pdf AbstractA 48 shark catfish Helicophagus waandersii from the Mun River, Thailand was monthly sampled in 19 consecutive months (June 2003 - December 2004) for studying in fecundity relationship, maturity size and spawning season. The fecundity ranged from 21,547 to 191,539 eggs which the average was 85,174?43,206 eggs fish" . The maximum fecundity belonged to a fish with 54.2 cm in total length (TL) and 1,067 g in body weight (BW) whereas the minimum fecundity belonged to a fish with 36.0 cm and 290 g. Fecundity increased with the increase of length and weight. The regression equations of fecundity (F) on total length (TL) and body weight (BW) were log F = 0.8445+2.4518 log TL (r=0.67) and log F = 2.8492+0.7308 log BW (r=0.7), respectively. The length at 50% maturity was estimated using frequency of occurrence of matured female was 42.01 cm which gave the expected fecundity as 66,933 eggs. Maximum GS1 was in June and the minimum GSI was in November. Shark catfish was a group-synchronous spawner with a short spawning season during the rainy season from May to July. Shark catfish started moving from the Mekong mainstream since January and developed the eggs in the Mun River. After spawning, parental stock moved back to deep pools in the Mekong mainstream whereas the juvenile moved farther to the upstream floodplain for nursing and feeding purposes. Then it moved backward and joins with adult stock in September. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : A Comparison of the Potency of Dopamine Antagonists on Spawning Induction in Thai Carp (Puntius gonionotus Bleeker)) ผู้เขียน: Naruepon Sukumasavin, Suwannee Sakulthong, Ravee Sangthong สื่อสิ่งพิมพ์:pdf AbstractThe potency of three dopamine antagonists (DA) i.e., domperidone (DOM), sulpiride (SUL), and metoclopramide (MET) on spawning induction in Thai carp was compared. Sexually mature female Thai carp were injected with DOM, SUL or MET at concentrations of 5, 10, 20 or 40 mg/kg alone or in combination with the LHRH analog Buserelin (BUS) at 5 or 20 ?g/kg and were allowed to spawn naturally. The results of the study showed that the three DA had the same potency when used alone. When used in combination with BUS at either low or high dosage, the order of potency of the three DA was 5 mg/kg DOM = 20 mg/kg MET = 40 mg/kg SUL. It was concluded that DOM had the highest potency on the spawning induction of the Thai carp. However, it was recommended to use 20 mg/kg MET in combination with 5 ?g/kg BUS to induce spawning of mature female Thai carp, when both potency and cost were considered. |
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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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ผลงานตีพิมพ์ในวารสารวิชาการReproductive Parameters of Indian Threadfin Alectis indicus in Andaman Sea, Thailandผู้แต่ง:Khamcharoen, M., Panwanitdumrong, K., Chaivichoo, P., Leamkom, T., Jutagate, T., Payooha, K., Dr.Uthairat Na-Nakorn, Professor , วารสาร: 
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