• Journal of Ecology and Environment
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• v.29 no.1
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• pp.35-39
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• 2006

During the breeding seasons in 2002 and 2003, the influences of vegetation cover on breeding processes of Black-tailed Gulls (Laurs crassirostris) were studied on Hongdo Island. We checked dutch sizes, calculated hatching success and survival rates on day 15 and a vegetation cover, There was significant positive relationship between vegetation cover and hatching success, and survival on day 15. In order to analyze the relationship, sample nests were categorized as 'exposed' and 'covered' nests, and the breeding processes at each nest were compared. Hatching success and survival on day 15 in covered nests were significantly higher than ones in exposed nests. However, in clutch size, there was no significant difference. The rate of the hatching and survival failure was different amongst the categorized nests. The primary cause of hatching failure in covered and exposed nests was 'disappeared', and the primary causes of survival failure on day 15 were 'disappeared' and 'killed by adults'. The failure in exposed nests was significantly larger than that of covered nests. In the breeding of Black-tailed Gulls on Hongdo Island, vegetation cover influenced the survival of eggs and chicks as the cover provided shelter against predators and extreme weather.

• Journal of Embryo Transfer
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• v.13 no.1
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• pp.37-41
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• 1998

This study was conducted to investigate the survival and hatching rates after refrozen-thawed bovine IVF blastocysts. The survival rates after refrozen-thawed bovine IVF blastocysts produced on day 7, day 8 and day 9, were 66.6%(16/24), 62.5%(15/24) and 65.3%(17/26), respectively. The survival and hatching rates after the first frozen-thawed bovine JVF blastocysts were 90.0%(27 /30) and 70.0%(21 /30), but in refrozen-thawed bovine IVF blastocysts were 66.2%(49 /74) and 45.9%(34 /74), respectively. The results of this study were suggest that refrozen-thawed bovine IVF embryos had survival ability.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.1
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• pp.25-32
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• 2010

The present study aimed to examine the effects of ${\gamma}$-linolenic acid (GLA) supplementation to in vitro culture (IVC) medium on in vitro developmental competence, freezability and morphology of in vitro matured and fertilized bovine embryos. In vitro produced (IVP) bovine zygotes were cultured in IVC medium supplemented with 0 (negative control), 15, 31, 62, 125, 250, 500 or 1,000 ppm GLA, 250 ppm linoleic acid albumin (LAA) and without any supplement as a control. Day 6 blastocysts derived from culture control were cultured in IVC medium containing either 62, 250 GLA or 250 LAA for 24 h, and at Day 7 were subjected to freezing or morphological examination by electron microscope. GLA 15 showed a tendency to have a higher cleavage rate at Day 2 (70.3%) than other groups. The hatching rate at Day 9 in LAA (38.2%) was significantly higher than the control and all treatment groups (p<0.05), while the blastocyst rate in LAA (32.4%) did not differ from those of 15 (30.5%), 31 (27.1%), and 62 GLA (33.1%) or the control (35.1%). GLA in concentrations of 125, 250, 500, and 1,000 ppm had significantly detrimental effect on the blastocyst rate compared to 15, 31 and 62 ppm GLA, LAA, and control groups (p<0.05). In contrast, the highest post-thaw survival rate (100%) was observed in the control group (p<0.01). Large lipid droplets were observed in the cytoplasm of trophoblastic cells, even in the control, but were abundant in GLA groups. Taking the results of the study into consideration, the addition of GLA to the culture medium for IVP bovine embryos at the dose of 15 ppm increased the developmental competence of zygotes and enhanced the cleavage rate up to Day 2. However, blastulation rate and post-thaw survival were not increased when GLA was added to the culture media.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.6
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• pp.862-867
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• 1999

The present study was undertaken to determine the effect of administration of exogenous progesterone early in gestation on uterine levels of IGF-I mRNA and on embryo survival at day 25 of gestation in the pig. Forty-one prepubertal gilts were induced into oestrus with PG600 and artificially inseminated at their subsequent naturally occurring oestrus. Gilts were then randomly assigned to one of three groups. Gilts in the two treatment groups were injected intramuscularly with 50 mg of progesterone either from day 2 to 14 (N=14) or from day 4 to 14 (N=15) after breeding while those in the control group (N=12) were given corn oil (0.5 ml) from day 2 to 14. Between days 25 and 28 of gestation, gilts were slaughtered and reproductive tracts were recovered. Endometrial tissue (1 g) was collected and analysed for IGF-I mRNA levels using a reverse transcription-polymerase chain reaction, Progesterone treatment, starting either on day 2 or 4 after breeding, neither significantly increased embryo survival rate by day 25 of gestation nor altered IGF-I mRNA levels in uterine tissue. However, across all samples, the IGF-I mRNA level in the uterus was highly correlated with embryo survival rate (r=0.8193, p<0.01), supporting the involvement of IGF-I in the regulation of porcine embryo development.

• Animal cells and systems
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• v.8 no.4
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• pp.313-317
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• 2004

A study was conducted to determine growth and survival rates of snakehead (Channa striata) larvae. Live foods such as Artemia salina nauplii, Moina micrura and bloodworm and artificial diet were given to larvae from 1-15 days after hatching as the 1st phase and from 15-30 days as the 2nd phase. In the 1st phase, the growth and survival rates of larvae fed with Artemia nauplii were significantly different from larvae fed with Moina (p < 0.05) with values of 28.5 mg, 49% and 26.7 mg, 31%, respectively. Meanwhile, all larvae fed with bloodworm (Chironomus sp.) or artificial diet (49% protein) died within 10 days of experiment. For the 2nd phase, growth of the fry fed with Artemia or Moina differed significantly from that fed with bloodworm or pellet (200.1, 187.7, 109.6 and 8.2 mg, respectively). Specific growth rate (SGR) of larvae fed with Moina was higher than that of larvae fed with Artemia (17.9 and 17.4% day$^{-1}$, respectively) in the 1st phase. In the 2nd phase, SGRs of larvae fed with Artemia (12.7% day$^{-1}$) or Moina (11.5% day$^{-1}$) were significantly higher than those of larvae fed with bloodworm (8.3% day$^{-1}$) or dry diet (6.1% day$^{-1}$). Generally, Artemia and Moina were suitable food for snakehead larvae during the first month of their life, and artificial diet was much less acceptable and resulted in poor growth and survival.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.551-556
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• 2020

Eel Anguilla japonica is an economically important inland culture fish species in East Asian countries, particularly in Korea, Japan, China, and Taiwan. In this study, the effects of feeding frequency on larval growth and survival rate were investigated. Eel larvae (average length, 6 mm) were fed a slurry-type diet containing shark eggs three, five, seven, or nine times per day. Survival rates differed significantly among the four experimental groups. Feeding frequencies of at least five and seven times a day were required until 15 and 30 days after hatching, respectively, to maintain an acceptable survival rate. Leptocephalus growth improved with increased feeding frequency until 15 days after hatching. The results suggest that providing an opportunity for early food intake enhances eel survival and growth in the early leptocephalus stage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.239-245
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• 2010

The effects of sediment and water movement on the survival and growth of Campylaephora hypnaeoides J. Agardh were examined in culture to elucidate why this species grows as an epiphytic alga. The survival and growth rates of Campylaephora tetraspores declined as the sediment concentration increased under both water-movement and no-water-movement treatments. After 5-day cultures under various sediment treatments, the respective survival and growth rates ranged from 27.32 to 78.63% and 0.22 to 0.29 $day^{-1}$ under the no-water-movement and from 15.66 to 82.69% and 0.19 to 0.31 $day^{-1}$ under the water-movement treatments. The maximum survival and growth of C. hypnaeoides tetraspores occurred at 20 and 40 ${\mu}mol$ photons $m^{-2}s^{-1}$, respectively. The survival of Campylaephora tetraspores and germlings declined with increasing dark period, but the tolerance of total darkness based on the survival rates was two-times greater for 5-day old sporelings than for tetraspores after 12 days. In conclusion, Campylaephora hypnaeoides grows as an epiphytic alga because its survivorship and growth decline rapidly with greater water movement and sedimentation and with lower light intensities.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.347-353
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• 1997

This study was to test whether in vitro/in vivo survival of vitrified mouse blastocysts was influenced by culture conditions and ET method. Mouse blastocysts were obtained from in vitro fertilization and cultured for 4 days in M16 medium, and they were vitrified in EFS40 which contained 40% ethlyene glycol, 18% Ficoll and 0.5 mol sucrose in PBS. In experiment I, in vitro and in vivo survival rate of these embryos were evaluated in different culture condition after thawing. When thawed embryos were cultured in M16 medium as a control, m-CR1 medium contained 20 amino acids (2% BME amino acis and 1% MEM non-essential amino acids solution) and 4 mg/ml BSA and cumulus monolayer cell co-cultured condition in mCR1 medium (10% FBS), their in vitro survival at 24 hr after thawing was not affected by culture condition (75.6, 83.1, 82.4%). However, in vivo survival rates of implantation in m-CR1 medium (80.4%) were significantly higher than those of M16 medium (51.2%), co-culture (57.1%) condition, although there was no difference in live fetuses rates on day 15 gestation (39.0, 49.0, 38.1%). In experiment II, the in vivo development potential of embryos by ET methods was examined. When blastocysts were transferred to the day 2, 3 pseudopregnant recipient without culture soon after thawing, no pregnant recipient was obtained on the day 2 pseudopregnancy, and 50% of pregnancy rates and 15.4% of live fetus rates were obtained on the day 3 pseudopregnant recipients. These results were significantly lower than those of transferred group (day 3 pseudopregnant recipients) after culture for 16 hr post thawing (73.5, 57.1%) (p<0.05). In experiment III, to elevate usability of delayed embryos in vitro/in vivo survival of vitrified embryos (day 4 early, day 5 early and expanding blastocyst) were examined. in vivo survival rates (live fetus, total implantation) were higher in day 4 early blastocysts (33.3, 66.7%) than in day 5 expanding blastocysts (29.0, 38.7%), although the highest in vitro survival rates were obtained in the day 5 expanding brastocysts (78.3%). Therefore, these results suggest that the in vitro/in vivo survival rates of vitrified embryos could be improve by the culture condition and ET method and that the in vivo development rates of delayed embryos were decreased with longer culture duration in vitro. It means that more effective cryopreservation was obtained in day 4 early blastocysts than in day 5 expanding blastocysts.

• Journal of Environmental Science International
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• v.5 no.2
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• pp.179-185
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• 1996

This study was conducted to investigate the effects of environmental factors such as temperature, salinity, pH, and UV light on-the survival of life-threatening Vibrio vulnificus. In the temperature range of 15 to $25^{\circ}C$, the numbers of V. vulnificus incieased during the 6-day incubation, but outside this range, the survival of V. vulnificus was poor. Incubation between 1 and $10^{\circ}C$ showed that V. vulnifcts survived poorly below $10^{\circ}C$. At sal:nities between 5 and 25ppt, the numbers of V. vulnificus increased or remained unchanged for 6-day. At salinities above this range, the numbers of V. vulnificus decreased. The optimal pH range was 6.5 to 8.0 and outside this range, the survival ratio of V. vulnificus was small. At 15-and $25^{\circ}C$, UV radiation was bactericidal for cultures of V, vulnificus. The counts of V. vulnificus were reduced approximately 10, 000-fold after 2h of UV light treatment at both temperatures. Above results mowed 1ha't environmental factors were effective on the survival of V. vulniucus in the environment.

• The Korean Journal of Malacology
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• v.26 no.3
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• pp.171-177
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• 2010

We examined physiological responses related to the survival, oxygen consumption and filtration rate of the blood cockle, Tegillaarca granosa as a result of salinity changes. The 44-day $LS_{50}$ (median lethal salinity) at $10^{\circ}C$ for adult and juvenile was 15.8 (confidence limits 13.5-18.2 psu) and 16.2 (confidence limits 14.1-18.4 psu) psu respectively, whereas the 11-day $LS_{50}$ at $25^{\circ}C$ for adult and juvenile was 16.8 psu (confidence limits 12.9-21.2 psu) and 22.4 (confidence limits 20.5-24.7 psu) psu respictively. In conditions of decreasing salinity, Oxygen consumption and filtration rates decreased or varied irregularly as salinity decreased. The results of this study could prove important in investigating causes of mass mortality and managing shellfish aquaculture farms.