Incubation Time Required for Hatching, and Ecological Characteristics of the Mode of Life Related with Total Numbers of the Suckers on Each Short Arm of the Hatched Juvenile Larvae of Octopus ocellatus (Cephallopoda: Octopodidae), in Western Korea

Kim, Sung Han,Jun, Je-Cheon The Malacological Society of Korea 2016 The Korean Journal of Malacology Vol.32 No.2

The incubation time required for hatching of O. ocellatus were investigated through the processes of egg and embryonic developments by the dissecting microscopic and visual observations. And differences in ecological characteristics of the plankton mode of life or the benthic mode of life according to total numbers of the suckers on each short arm of the hatched juvenile larvae of O. ocellatus were studied by comparisons with other octopodidae species. Compared with the recent a few results reported by other researchers associated with the incubation time required for hatching by female adult mother of O. minor (73-90 days after spawning at $20.9-21.5^{\circ}C$ ranges), in this study, the incubation time required for hatching by female adult mother of O. ocellatus was 56-57 days after spawning at $11.0-20.4^{\circ}C$. Therefore, the incubation time required for hatching by female adult mother varied with Octopodidae species. In this studies, each ovarian egg laid by a female was connected to an egg string attaching to the surface of the wall or bottom of vacunt shell of Rapana venosa. Egg and embryonic developments of this species were studied in the indoor aquaria, in the specific gravity ranging 1.024-1.025. the hatched juvenile of O. ocellatus is 10.3 mm in the mean total length and 4.5 mm in mantle length, and each of its short arms has 18-20 suckers. The just hatched juvenile larvae of O. ocellatus enter the benthic mode of life (benthic larval stage) after hatching. In particular, regarding differences in ecological characteristics of the mode of life according to total numbers of the suckers, O. vulgaris may not need to have many suckers because they enter the planktonic mode of life after hatching, however O. ocellatus may need to have many suckers, because they should adapt to the benthic mode of life. And also the just hatched juvenile larvae of O. minor (bearing many suckers more than O. ocellatus) enter the benthic mode of life (benthic larval stage) after hatching. Therefore, the total number of the suckers on each short arm of the hatched juvenile larvae can be used for determining whether an octopus species has planktonic larval stages or benthic larval stage (benthic mode of life). In particular, The intracohort cannibalism phenomena appeared at the hatched juvenile larval stage because the larval stage of O. ocellatus and O. minor enter into the benthic larval stage in the early stage, unlike entering into the plaktonic larval stage in other Octopus species such as O. vulgaris: at this time, the early hatched larvae fed the late hatched larvae (they are the same species and almost same ages). Therefore, the intracohort cannibalism pheneomena occur in the just hatched juvenile stage of only O. ocellatus and O. minor.

Incubation Time Required for Hatching, and Ecological Characteristics of the Mode of Life Related with Total Numbers of the Suckers on Each Short Arm of the Hatched Juvenile Larvae of Octopus ocellatus (Cephallopoda: Octopodidae), in Western Korea

김성한,전제천 한국패류학회 2016 The Korean Journal of Malacology Vol.32 No.2

The incubation time required for hatching of O. ocellatus were investigated through the processes of egg and embryonic developments by the dissecting microscopic and visual observations. And differences in ecological characteristics of the plankton mode of life or the benthic mode of life according to total numbers of the suckers on each short arm of the hatched juvenile larvae of O. ocellatus were studied by comparisons with other octopodidae species. Compared with the recent a few results reported by other researchers associated with the incubation time required for hatching by female adult mother of O. minor (73-90 days after spawning at 20.9-21.5℃ ranges), in this study, the incubation time required for hatching by female adult mother of O. ocellatus was 56-57 days after spawning at 11.0-20.4℃. Therefore, the incubation time required for hatching by female adult mother varied with Octopodidae species. In this studies, each ovarian egg laid by a female was connected to an egg string attaching to the surface of the wall or bottom of vacunt shell of Rapana venosa. Egg and embryonic developments of this species were studied in the indoor aquaria, in the specific gravity ranging 1.024-1.025. the hatched juvenile of O. ocellatus is 10.3 mm in the mean total length and 4.5 mm in mantle length, and each of its short arms has 18-20 suckers. The just hatched juvenile larvae of O. ocellatus enter the benthic mode of life (benthic larval stage) after hatching. In particular, regarding differences in ecological characteristics of the mode of life according to total numbers of the suckers, O. vulgaris may not need to have many suckers because they enter the planktonic mode of life after hatching, however O. ocellatus may need to have many suckers, because they should adapt to the benthic mode of life. And also the just hatched juvenile larvae of O. minor (bearing many suckers more than O. ocellatus) enter the benthic mode of life (benthic larval stage) after hatching. Therefore, the total number of the suckers on each short arm of the hatched juvenile larvae can be used for determining whether an octopus species has planktonic larval stages or benthic larval stage (benthic mode of life). In particular, The intracohort cannibalism phenomena appeared at the hatched juvenile larval stage because the larval stage of O. ocellatus and O. minor enter into the benthic larval stage in the early stage, unlike entering into the plaktonic larval stage in other Octopus species such as O. vulgaris: at this time, the early hatched larvae fed the late hatched larvae (they are the same species and almost same ages). Therefore, the intracohort cannibalism pheneomena occur in the just hatched juvenile stage of only O. ocellatus and O. minor.

Implications of High Temperature and Low Humidity on the Hatching in the Silkworm, Bombyx mori L. Under LD 12 : 12 Condition

Reddy P. Lakshminarayana,Naik S. Sankar,Reddy N. Sivarami Korean Society of Sericultural Science 2005 International Journal of Industrial Entomology Vol.11 No.2

The implications of temperature (25, 30 and $35^{\circ}C$) and relative humidity (RH; 60, 70 and $80\%$) on the hatching rhythmicity and hatching parameters (percentage and duration) were studied in the silkworm, Bombyx mori L. under natural photoperiod (LD 12 : 12). Disease free layings (DFLs) of two pure silkworm breeds, Pure Mysore (PM, a multivoltine breed) and $NB_4D_2$ (a bivoltine breed), and their hybrid, $PM{\times}NB_4D_2$ were introduced into the experimental conditions on the $3^{rd}$ day of oviposition till completion of hatching. The hatching rhythm was predominantly diurnal under all temperature and humidity conditions, with peaks just after 'lights-on' phase (6 hrs). Extreme temperature and humidity conditions did not alter the hatching rhythmicity, but prolonged the hatching durations, extending it to the next day, coupled with reduced hatching percentage in PM and $PM{\times}NB_4D_2{\cdot}In\;NB_4D_2$, on the other hand, hatching did not extend to the next day. Hatching percentage in this breed, however, reduced below the economic level under high temperature and low humidity conditions. The high temperature and low humidity together, though did not alter the rhythmicity, seems to exert synergetic effect on the hatching percentage and its duration in the silkworm, B. mori.

생쥐배아의 부화와 탈각에 미치는 Pronase의 영향

문신용,최성미,김희선,류범용,오선경,서창석,김석현,최영민,김정구,최규홍,이진용,Moon, Shin-Yong,Choi, Sung-Mi,Kim, Hee-Sun,Ryu, Buom-Yong,Oh, Sun-Kyung,Suh, Chang-Suk,Kim, Seok-Hyun,Choi, Young-Min,Kim, Jung-Gu,Choi, Kyu-Hong,Lee, Jin-Y 대한생식의학회 2000 Clinical and Experimental Reproductive Medicine Vol.27 No.4

Objective: Hatching of the blastocyst from the zona pellucida (ZP) is a key event in mammalian implantation. In vivo, two factors have been identified as possible mediators of hatching: lysis of the ZP by substances elaborated either from the embryo or female reproductive tract and pressure exerted on the zona by expansion of the blastocyst. Two methods of zona manipulation were already in use to enhance the ability of embryos to hatch: mechanical PZD and chemical ZD by acidic Tyrode's solution. But several controversies of each method have been reported. The purpose of this study was to investigate the effect of pronase for mouse embryo hatching. Methods: Mouse embryos were obtained following ovulation induction of $F_1$ animals. Fresh and cryo-thawed morula embryos were exposed to 0.5, 1.0, 2.0, 5.0 ${\mu}g/ml$ pronase in Ham's F10 for 72 hrs. Main outcome measures were the rates of partial hatching and completely hatched blastocysts, and cell number of it. Results: In fresh and cryo-thawed group, the rates of completely hatched blastocyst were significantly higher in 5 ${\mu}g/ml$ pronase treatment group than control group. There was no difference in completely hatched blastocyst total cell number between pronase treatment group and control group. This suggest that pronase treatment did not harmful in mouse embryo development. In pronase treatment group, zona pellucida were thinner than control group. Conclusion: The addition of pronase to culture media may accelerate the hatching of embryo. So, enzymatic treatment of the zona may provide a valuable and effective assisted hatching technique for human in-vitro fertilization-embryo transfer.

Activation of peroxisome proliferator-activated receptor δ (PPARδ) accelerates blastocyst hatching in mice

Jung Ah Yoon,Hee Jung Kang,Soo Jin Hwang,Hyunjung Lim,Haengseok Song 한국발생생물학회 2011 한국발생생물학회 학술발표대회 Vol.30 No.-

In particular, maternal prostacyclin (PGI2) is critical for embryo implantation and the action of PGI2 is not mediated via its G protein-coupled membrane receptor, IP, but its nuclear receptor, peroxisome proliferator-activated receptor δ (PPARδ). Recently, several studies have shown that PGI2 enhances blastocyst development and/or hatching rate in vitro, and subsequently implantation and live birth rates in mice. However, the mechanism by which PGI2 improves preimplantation embryo development in vitro remains unclear. Using molecular, pharmacologic and genetic approaches, we show that PGI2-induced PPARδ activation accelerates blastocyst hatching in mice. mRNAs for PPARδ, RXRs (heterodimeric partners of PPARδ) and PGI2 synthase are temporally induced after zygotic gene activation and their expression reaches maximum levels at the blastocyst stage, suggesting that functional complex of PPARδ can be formed in the blastocyst. Carbaprostacyclin (cPGI, a stable analogue of PGI2) and GW501516 (a PPARδ selective agonist) significantly accelerated blastocyst hatching but did not increase total cell number of cultured blastocysts. Whereas U51605 (a PGIS inhibitor) interfered with blastocyst hatching, GW501516 restored U51605-induced retarded hatching. In contrast to improvement of blastocyst hatching by PPARδ agonists, PPAR antagonists significantly inhibited blastocyst hatching. Furthermore, deletion of PPARδ at early stages of preimplantation mouse embryos caused delay of blastocyst hatching, but did not impair blastocyst development. Taken together, PGI2-induced PPARδ activation accelerates blastocyst hatching in mice.

쥐노래미 Hexagrammos otakii 난의 부화에 미치는 수온의 영향 및 자치어의 성장과 생존에 미치는 수온과 먹이의 영향

강희웅,정의영,이창훈,이정열 한국어류학회 2002 韓國魚類學會誌 Vol.14 No.2

쥐노래미 Hexagrammos otakii의 부호조건 및 자치어의 성장 및 생존에 미치는 영향을 조사하기 위하여 수온에 따른 부화 소요시간 및 부화율, 자치어의 성장과 생존에 미치는 수온과 먹이조건을 조사하였다. 쥐노래미 수정란의 수온별 부화 소요시간은 수온이 높을수록 짧았다. 부화율은 12℃에서 가장 높았으나, 반면 수온이 14℃ 이상으로 상승하면 급격히 감소되었으며 18.0℃이상에서는 비정상 기형 개체들이 출현하였다. 부화 후 70일 경과 후 수온별 자치어의 초기 성장과 생존율(%)은 수온이 높은 조건(16℃)일수록 낮은 수온조건보다 성장이 빨랐던(P<0.01) 반면, 생존율은 낮은 수온(10℃)조건에서 높게 나타났다. 70일간 먹이공급계열이 따른 자치어 사육실험에서 최적 성장과 높은 생존 조건은 윤충류(Brachionus plicatilis, 부화 후 1~10일) + Artemia nauplii(부화 후 10~20일) + 배합사료(부화 후 15~70일)를 공급한 실험군으로 나타났다. 자치어의 빠른 성장과 생존율을 높이기 위해서는 되도록 일찍 배합사료에 먹이붙임을 하는 것이 바람직하다고 판단된다. To obtain optimal rearing conditions for seedling production of the greenling Hexagrammos otakii, the effects of seawater temperature on hatching of egg, and seawater temperature and feeding regime on growth and survival of hatched larvae were studied. The hatching time of fertilized eggs of H. otakii decreased with increasing seawater temperature. Total length of hatched larvae was in the range of 7.21~8.16㎜. The highest hatching rate was found at 12℃. As seawater temperature increased higher than 14℃, the hatching rate sharply decreased. Abnormal larvae were found at 18.0℃. Seawater temperature affected significantly the growth and survival of H. otakii larvae(P<0.001). After rearing larvae for 70 days after hatching, we found the growth rate highest when seawater temperature was highest(16℃), whereas survival was highest when seawater temperature was lowest(10℃). Feeding regime also affected significantly the growth and survival of H. otakii larvae(P<0.001). The most efficient feeding regime was under the conditions of feeding rotifer(Brachionus plicatilis) during days 1~10 after hatching+ Artemia nauplii during days 10~20 after hatching+commercial feeds during days 15~70 after hatching. To ensure rapid growth and higher survival of H. otakii larvae, commercial feeds should be provided as early as possible.

생쥐 배에서 Prostaglandin의 부화과정 참여여부에 관한 연구

류지아(JA Ryu),유한기(HK Yoo),윤숙영(SY Yoon),배인하(IH Bae) 대한산부인과학회 1997 Obstetrics & Gynecology Science Vol.40 No.5

Most mammalian embryos implant on the uterine endometrium after hatching from zona pellucida of the expanded blastocyst and pregnancy takes place. The blastocysts produce and control a variety of prostaglandins which activate a few proteolytic enzymes that dissolve the zona pellucida of the embryos. In the present study, the goal was to investigate the indomethacin and aspirin(inhibitors of cyclooxygenase pathway which regulates the pathway from arachidonic acid to prostaglandins), which can affect the hatching and implantation of the mouse embryos by the treatment of the different dose level of indomethacin and aspirin in the culture of mouse embryos. The female and male ICR mice, 6~8 weeks and were used for superovulation and mating and M16 was used as a basic culture medium. The above results can be summarized as following: 1. Indomethacin seemed to inhibit the development of the mouse embryos and hatching process because of inhibiting or blocking the activation of hatching related enzymes and high dose of indomethacin inhibited implantation. 2. Aspirin had no effect on the hatching of the embryos at the dose of 0.16 mg/ml. 3. FBS seemed to contain a factor which induced outgrowth of the embryo whereas BSA did not and outgrowth did not take place in the BSA contained medium. 4. Blastocysts produced enough prostaglandins F2α which was needed for the hatching whereas they needed a factor for implantation which might be produced in the endometrium or exuded from the blood. In conclusion the concentration of indomethacin used in the present study inhibit hatching of the blastocysts. This seems to be caused by inhibiting the synthesis of the proteins need for hatching. The factor that induce the outgrowth of the blastocysts does not seem to be produced in the blastocysts themselves but seem to be present in the FBS.

Gene expression changes in silkworm embryogenesis for prediction of hatching time

박종우 한국잠사학회 2023 International Journal of Industrial Entomology Vol.46 No.1

The silkworm's dormancy and embryonic development are accomplished through the interaction of various genes. Analysis of the expression of several interacting genes can predict the embryonic stage of silkworms. In this study, we analyzed the changes in the expression level of genes at each stage during the embryonic development of dormant silkworm eggs and selected genes that can predict the hatching time. Jam123 and Jam124 silkworms were collected after egg laying, and the silkworm eggs were preserved using a double refrigeration method and expression analysis was performed for 23 genes during embryogenesis. There were 5 genes showing significant changes during embryogenesis: UDP-glucuronosyltransferases (BmUGTs), heat shock protein hsp20.8 (BmHsp20.8), Cytochromes b5-like proteins (BmCytb5), Krüppel homolog 1 (BmKr-h1), and cuticular protein RR-1 motif 41 (BmCpr41). As a result of quantitative comparison of the expression levels of these 5 genes through real-time PCR, the BmUGTs gene showed a difference between Jam123 and Jam124, making it difficult to see it as an indicator for predicting hatching time. However, the BmHsp20.8 gene had a common expression decreased at the imminent hatching stage. In addition, it was confirmed that the expression level of the BmCytb5 gene decreased to the lowest level at the time of imminent hatching, and the expression of the BmKr-h gene was made only at the time of imminent hatching. The expression of the last BmCpr41 gene can be confirmed only at the time of imminent hatching, and it was confirmed that it shows a rapid increase right before hatching. Taken together, these results suggest that expression analysis of BmHsp20.8, BmCytb5, BmKr-h1, and BmCpr41 genes can determine the stage of embryogenesis, predict hatching time, which facilitate better management of silkworm eggs

Hatching and Livability of the Black-tailed Gull (Larus crassirostris) in Relation to the Egg Size in Hongdo Island

Jae-Pyoung Yu(유재평),Byun-Sun Chun(전병선),In-Kyu Kim(김인규),Jeong-Hoon Kang(강정훈),In-Hwan Paik(백인환),Kyu-Hwang Hahm(함규황),Woon-Kee Paek(백운기) 한국조류학회II 2006 한국조류학회지 Vol.13 No.1

본 연구는 천연기념물 335호 해조류번식지로 지정되어 있는 홍도에서 1988년 4월 초순에서 7월 중순까지 70개의 괭이갈매기 둥지에서 산란에서 이소까지의 번식생태에 관하여(알 크기와 낳는 순서가 새끼의 부화율과 성장률에 미치는 영향에 대하여) 조사한 것이다. 괭이갈매기의 한배산란수는 2.43±0.51개 였고, 포란기간은 평균 26.4일(범위 24~29일, n=31)이었다. 알 측정치의 평균은 장경 61.3±2.3㎜, 단경 43.1±1.3㎜, 무게 56.1±3.7g이었고, 새끼의 무게는 부화시 49.3±8.7g이었고, 5일경 무게는 110.6±25.5g, 10일경 무게 235.9±37.8g이었다. 부화율은 91.11%였고, 생존율은 81.71%였으며, 생존율은 15일까지 생존해 있는 새끼들을 대상으로 계산하였다. 첫 번째 낳은 알이 두 번째, 세 번째 낳은 알보다 무거웠으며, 부화율, 생존율 또한 높았다. 따라서 산란 순서는 새끼가 부화하고 생존하는데 상당히 중요한 요인이 되고 있다는 것을 의미한다. This research aims at explicating the influence of egg size and the order of laying on the hatching rate and the livability in seventy nests of Larus crassirostris from early April to mid July in 1988 in Hongdo, a place designated as Natural Monument No. 335 for a breeding place of seabirds. The average number of brood is 2.43±0.51, and the period of the Black-tailed Gulls' incubation is 26.4 days in average (Range 24~29 days, n=31). The size of the egg was 61.3±2.3㎜ in the major axis and 43.1±1.3㎜ in the minor axis respectively, and the weight was 56.1±3.7g. The weight of the first chick was 49.3±8.7g, and the weight of the first chick. On the fifth day and tenth day after hatching, was 110.6±25.5g and 235.9±37.8g respectively. The hatching rate was 91.11% and the livability was 81.71%. The livability was calculated by investigating chicks survival until 15 days after hatching. The results showed that the first eggs are a slightly bigger and heavier than the second and third one. Furthermore, the hatching rates of the first and second-laid eggs are higher than the third one, as well as the livablity of the two eggs. Therefore, it could be concluded that the size of the egg and the order of egg-laying have important influences on the hatching rate and livability.

Inhibition of Meloidogyne incognita Egg Hatching by Herbal Extracts

G.A.A. Elbadri,Dong Woon Lee(이동운),Jung Chan Park(박정찬),Ho Yul Choo(추호렬),Hyeong Hwan Kim(김형환) 한국농약과학회 2008 농약과학회지 Vol.12 No.2

The inhibitory effect of herbal extracts using methanol and hexane collected from Sudan and Korea was evaluated on egg hatching of Meloidogyne incognita. The concentration of herbal extracts were 10,000, 1,000 and 100 ppm, respectively. They were treated to Meloidogyne incognita eggs after 3, 7, and 21 days of hatching. All herbal extracts inhibited egg hatching significantly compared to the control. The degree of inhibition was directly related to the concentration of the extracts. At 10,000 ppm, very fewer individuals were hatched at all the periods of exposure with the exception of the extract of fruits of Quisqalis indica which gave 84.4 and 54.5% at 7 and 21 days, respectively. Egg hatching was completely ceased, especially after 7 days for most of the extracts. While at 1,000 ppm relatively high numbers of eggs were hatched compared to the higher concentration, as well the extracts Q. indica reported many number of hatched eggs compared to others, especially at 21 days. On the other band, the extract from pods of Cucumis mello var agrestis gave the least hatching number of eggs at all periods of exposure which gave 2, 8, and 3% at 3, 7, and 21 days, respectively in comparison to the control. Whereas at 100 ppm, inhibition increased with exposure time. However, the extract leaf of Desmodium caudatum represented the fewer hatching eggs at 3 and 7 days.