• Korean Journal of Animal Reproduction
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• v.8 no.2
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• pp.100-109
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• 1984

This study was conducted to find out the changes of progesterone and estradiol-17$\beta$ levels in the serum of female Korean native goats during the reproductive stages such as the estrous cycle, pregnancy and periparturient period. Nine heads of female Korean native goats of 3 year old in average and weighing 35.7$\pm$1.4 kg were offered for the experiment. Blood samples were taken at 0, 1, 2, 5, 7, 10, 13, 15, 18 and 19 days after onset of estrus, and 1, 30, 60, 90, 120 and 149 days of pregnancy, and -5, -2, -1, 0, +1, +2 and +5 days of periparturient period where minus figures denote the days before paturition. The progesterone, estradiol-17$\beta$ in the serum samples were assayed by radioimmunoassay methods. The results of this study are summarized as follow: 1. The progesterone levels during the estrous cycles reached a peak level of 0.98$\pm$0.60ng/ml at 13 days after onset of estrus and decreased thereafter and were lower than 0.09$\pm$0.02mg/ml on the first day of estrus. 2. The estradioe17$\beta$ levels during the estrous cycles showed a peak level of 15.97$\pm$1.72pg/ml at onest of estrus, and decreased (5.41$\pm$0.51pg/ml-9.09$\pm$1.82pg/ml) during luteal phase. 3. The progesterone levels during the gestation period increased from day 1 and peaked at 90 days after mating and then decreased until 149 days. The peak level was 6.27$\pm$0.23ng/ml at 90 days. 4. The estradiol-17$\beta$ levels during the gestation period showed gradual increase, which were 9.03$\pm$0.88, 32.96$\pm$2.85, 46.03$\pm$2.42, and 54.06$\pm$1.64pg/ml on 30, 60, 90 and 120 dyas after mating respectively. 5. The progesterone levels measured from 5 days before the parturition to 5 days after showed the highest level at the shart of measurement (4.46$\pm$0.31ng/ml) and decreased gradually and bottomed out at one day post-partum and thereafter (0.24$\pm$0.02-0.45$\pm$0.06ng/ml). 6. The estradiol-17$\beta$ levels measured during the same periparturient period as progesterone showed increase to reach the peak level at 1 day before parturition and decreased rapidly thereafter (-5 dyas 69.46$\pm$3.62, -2 days 107.07$\pm$1.91, -1 days 137.83$\pm$7.54, 0 days 50.06$\pm$6.71 and +1 to +5 days 3.21-4.72 pg/ml).

• Toxicological Research
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• v.9 no.1
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• pp.73-82
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• 1993

LBD-007, a newly developed recombinant human interferon alphaA, was at dose levels of 0, 3$\times$$10^6$, 6$\times$ $10^6$ and 12$\times$1$10^6$ IU/kg/day administered subcutaneously to Sprague-Dawley male rats from premating to mating period and to females from premating to early gestation period. Effects of test agent on reproductive performance of both sexes and embryonic development were examined. 1. No treatment-relared changes in food consumption, body weight and necropsy findings were observed in parent animals.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.187-193
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• 1998

The effects of medium, incubation temperature, incubation period, pH of medium and $CO_2$ ondition during mycelial growth were investigated to study the factors associated with the formation of oidia in Flammulina velutipes. Oidia formation was increased when mycelial growth was poor, while oidia formation was inhibited in optimum condition of mycelial growth. Mating type of oidia was investigated to examine the effect of oidia formation on dikaryotic strain. Di-mon matings between oidia strains and original dikaryotic strain were carried out. Monokaryotic strains derived from oidia showed only one genotype. Seventy percent among Dimon mating strains showed slow mycelial growth and low yield of fruit-body, but others showed similar or high mycelial growth and yields in comparision with original dikaryon strain. One strain from di-mon mating demonstrated some differences in isozyme band pattern.

• Korean journal of applied entomology
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• v.51 no.3
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• pp.223-230
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• 2012

Some high frequency sounds alter physiological processes of the beet armyworm, Spodoptera exigua. This study investigated the effect of ultrasound (${\geq}$ 20 kHz) on larval feeding, pupal development, and adult mating behavior of S. exigua. Ultrasound suppressed feeding behavior of fifth instar larvae, and 30 or 45 kHz treatment inhibited more than 50% of feeding activity. Larvae treated with ultrasound exhibited alterations in major nutrient compositions in the hemolymph plasma. Plasma protein levels decreased with an increase in ultrasound frequency. In contrast, sugar levels increased with an increase in ultrasound frequency. Lipid levels increased with an increase in ultrasound frequency up to 30 kHz and then decreased at treatments > 30 kHz. Hemocytes, the fat body, and epidermis expressed three heat shock proteins and apolipophorin III. Ultrasound treatment markedly inhibited expression of some stress-related genes. Ultrasound treatment also inhibited S. exigua pupal development by extending the pupal developmental period and preventing adult emergence. Last, ultrasound treatment significantly inhibited adult mating behavior, which resulted in a significant decrease in female fecundity. These results show that ultrasound is a physiological stress to S. exigua.

• Development and Reproduction
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• v.22 no.1
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• pp.85-94
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• 2018

Endocrine disruptors have been concerned in toxicology but now challenged as physiological point especially concerned with exposing dose and period. In this study the low-dose chronic administration of di(2-ethylhexyl) phthaltae (DEHP) during reproductive period was examined to evaluate the possible roles. Adult male and female CD-1 mice were exposed to DEHP with drinking water containing $133{\mu}g/L$ and $1,330{\mu}g/L$ DEHP in water according to OECD 433 guide line and sacrificed just after weaning. The weights of uterus and ovary were decreased by drinking of $1,330{\mu}g/L$ DEHP water. There was not adverse effects on either accumulated mating rate and mating rate depend on estrus stage, pregnancy duration, and sex ration at birth. However, the accumulated rate of successful delivery and litter size were significantly high at $1,330{\mu}g/L$ DEHP water. The number of epididymal sperm was significantly increased by drinking of $1,330{\mu}g/L$ DEHP water. In addition, the number of follicles (primary, secondary, tertiary) were more many than control at $1,330{\mu}g/L$ DEHP water drunk mother. Though further studies are needed to identify what are the mechanism of DEHP in folliculogenesis and spermatogenesis. From this study we firstly report the effect of low-dose chronic administration of DEHP with drinking could change the ovarian follicle population size and spermatogenesis rate. Put together, those finding is different from previous high-dose effects and suggest the physiological role of DEHP in gonads and uterus.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.273-286
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• 2013

Objectives: The present study was conducted in order to investigate the reproductive toxicity in rats exposed to 1,4-dichlorobutane. Methods: The test chemical was administered orally at 0, 8.3, 50 and 300 mg/kg/day. Males were administered daily for 10 weeks prior to the mating period. Females were administered from between two weeks before mating to the 21stday of lactation. Results: In both sexes, a decrease in body weight and an increase in the weights of the liver and kidneys were observed. In males, discoloration of the liver, hepatocyte hypertrophy and mineralization in the kidneys were observed. In females, animal deaths, dystocia and pup deaths due to maternal dysfunction were observed. In F1 animals of both sexes, a decrease in body weight was observed at 300 mg/kg/day. An increase in the weights of the liver in both sexes, mineralization in the kidneys of males, animal deaths, hepatocyte hypertrophy and pup deaths due to maternal dysfunction were observed at 50 mg/kg/day. Mineralization in the kidneys of males was observed at 8.3 mg/kg/day. Therefore, the no-observed-adverse-effect levels (NOAELs) of 1,4- dichlorobutane were considered to be under 8.3 mg/kg/day for males, 8.3 mg/kg/day for females, more than 300 mg/kg/day for fertility in both sexes, 8.3 mg/kg/day for maternal functions and 50 mg/kg/day for F1 offspring. The absolute toxic dose was believed to be 8.3 mg/kg/day for males, 50 mg/kg/day for females, 50 mg/kg/day for maternal functions and 300 mg/kg/day for F1 offspring. However NOAEL for fertility could not be determined since there were no treatment-related changes. Conclusions: Under the present experimental conditions, 1,4-dichlorobutane is a Category 1B Reproductive Toxicant (presumed human reproductive or developmental toxicant).

• Korean Journal of Animal Reproduction
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• v.16 no.4
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• pp.301-310
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• 1993

This experiment was performed to develop simple practical methods for short term preservation of rabbit embryos. A total of 55 cross bred does were superovulated by intramuscular injection of PMSG and HCG. Embryos were recovered at 25~30 hrs, 60~65 hrs and 80~85 hrs after mating and selected by morphological examination. Four cell stage, morulae and blastocyst embryos were stored in PBS enrich with 1, 10, 20 and 40% heat-treated FCS at 4, 20, 30 and 37$^{\circ}C$, respectively. Embryos were examined morphologically at 24, 48 and 72 hrs following storage. The result obtained in this experiment were summarized as follows: The superovulation was induced by PMSG 200 IU and HCG 100 IU. The average number of ovulation points and embryos recovered by collection time were 19.0, 15.6(25~30 hr), 17.3, 13.5(60~65 hr) and 19.2, 14.4(80~85 hr), respectively. And recovery rates of embryos recovered at 25~30 hr, 60~65 hr and 80~85 hr after mating were 62.8%(4 cell), 84.7%(morulae) and 79.6%(blastocyst), respectively. On the other hand, the average number of ovulation points collected by the no, of operations for the repeated collection was 17.3(60~65 hr), 19.2(80~85 hr) in 1st and 9.4(60~65 hr), 10.6(80~85 hr) in 2nd surgery, respectively. There was a significant decrease(P<0.05) in the number of ovulation points the 2nd surgery as compared to the 1st surgery. All of the 4-cell stage embryos stored at 4$^{\circ}C$ for 48 hrs showed the same morphology throught the storage period, on the contrary, 4-cell stage embryos stored at 2$0^{\circ}C$ and 3$0^{\circ}C$ for 48 hrs showed degeneration embryos and stored at 37$^{\circ}C$ for 24 hrs showed degeneration embryos. Morulae and blastodcyst stored at 4, 20, 30 and 37$^{\circ}C$ for 24 hrs showed degeneration embryos. All of the blastocyst stored at 37$^{\circ}C$ for 72 hrs showed degeneration embryos.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.105-110
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• 2000

Sex pheromone composition was analyzed for Dichocrocis punctiferalis, which attacksapple, peach, chestnut fruits, etc., and its behavioral and field trapping studies were conducted to developa monitoring system with its sex pheromone. Virgin females showed maximum mating behavior andhairpencil extrusion behavior between 4-5 hrs after lights-off under 16L18D photoperiod and 26rf 1 "C.During this period, two sex pheromone components, ElO-hexadecenal and ZlO-hexadecenal, weredetected by GC analysis in the hexane extract of abdominal tips of virgin females. The best attraction ofmales to various synthetic sex pheromone blends was obtained at the 70 : 30 ratio of ElO-hexadecenal andZ10-hexadecenal for hair pencil extrusion and at the 80 : 20 ratio for flying upwind response. The highestattractiveness in fields was obtained between 70 : 30 and 80 : 20 from several tests in apple, peach andchestnut orchards.and chestnut orchards.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.59-67
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• 1996

A new composite antibiotic, SM-101(sulbactam·metampicillin), was at dose levels of 0, 375, 750 and 1500 mg/kg/day administered intravenously to pregnant Sprague-Dawley rats during the organogenetic period. Two-third of dams per group were subjected to caesarean section on day 20 of pregnancy and the remaining 10 dams per group were allowed to deliver. Effects of test substance on dams, embryonal development of F1 fetuses, as well as growth, behaviour and mating performance of F1 offspring were examined. In dams, two deaths occurred at 375 and 1500 mg/kg, respectively. The decrease in the weight of adrenal glands of the 1500 mg/kg group was observed. The prolongation of pregnancy period was found at 1500 mg/kg. F1 fetuses showed no changes related to the treatment of SM-101. In F1 offspring, the increase in spleen weight was seen at all doses treated. No treatment-related abnormalities were observed in each treated group in terms of development, behaviour and reproductive performance. In F2 fetuses, no drug-induced abnormalities occurred at all doses. The results show that the no-effect dose levels (NOELS) for dams and Fl offspring are under 375 mg/kg/day and NOELs for F1/F2 fetuses are over 1500 mg/kg/day.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.105-111
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• 2004

A total of 301 Thoroughbred mares were investigated the characteristics of breeding in the local areas in Jeju during the period from February 2000 to July 2001. The pregnancy rate and foaling rate in 143 mares were 93.0%, 72.0%, respectively, and mean gestational length was 339.3 days in 2000. The pregnancy rate in 158 mares was 86.7% in 2001. Mature follicles were ovulated in right(46.0%), left(45.2%), and bilateral(7.8%) ovary. The incidence of multiple pregnancies in 158 mares between 15 days and 45 days after mating were 89.3%(single), 10.1%(twin), and 0.6%(triple). The incidence of EED was 13.3%. Also uterine cyst and fluid had an bad influence on mare's pregnancy. These results suggest that regular monitoring of the pregnancies and maintaining of good uterine condition improve the pregnancy rates and foaling rates during breeding season.