검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 45

        1.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Because multiple ovulation embryo transfer (MOET) in cattle includes several benefits such as wide spreading of genetically superior offspring for long distance, this biotechnological method has been widely applied to Hanwoo. When the recipients are not stayed close after embryo recovery from donor, the embryos are moved to other farms via several vehicles (car, train, and airplane). However, air travel induces lesser oxygen level, increased vibration, lower air pressure, higher noise, and increased exposure of cosmic radiation to living things than ground level. It was still unknown that fresh embryos obtained from multiple ovulation of Hanwoo could maintain their fertility after being transported via air plane, the present case report introduced a clinical case of MOET in Hanwoo after shipping fresh embryos via air transportation. The donor was multi-ovulated via follicle-stimulating hormone series of injection, which was followed by a gonadotrophin-releasing hormone injection and artificial insemination twice. The embryos were recovered by the uterine flushing, packed in ministraws, transported to recipients for 6 h including 1 h air flight, and then transferred to the synchronized recipients. During pregnancy diagnosis of early gestation period, 5 of 7 recipients (71.4%) presented no heat signs and showed fetal sacs with fluid under transrectal ultrasonography. After normal gestation period, all recipients naturally delivered healthy calves (male n = 2 and female n = 3) without abortion, stillbirth, and premature birth. The present case report indicated that transportation of fresh embryos for MOET via domestic flight in Korea did not affect to their fertility.
        4,000원
        2.
        2020.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the effect of variation in the number of somaticcell- cloned embryos and their developmental stage at transfer on pregnancy, as well as the influence of the estrus status of recipient pigs on in vivo development of cloned porcine embryos after embryo transfer. For somatic cell nuclear transfer (SCNT), fibroblast cells were obtained from a male porcine fetus. Recipient oocytes were collected from prepubertal gilts at a local abattoir and then cultured. After SCNT, reconstructed embryos of different numbers and developmental stages were transferred into recipient pigs. The developmental stage of the cloned embryos and the number of transferred embryos per surrogate showed no significant differences in terms of the resulting cloning efficiency. However, the pregnancy rate improved gradually as the number of transferred cloned embryos was increased from 100- 150 or 151-200 to 201-300 per recipient. In pre-, peri-, and post-ovulation stages, pregnancy rates of 28.6%, 41.8%, and 67.6% and 16, 52, and 74 offspring were recorded, respectively. The number of cloned embryos and estrus status of the recipient pig at the time of transfer of the cloned embryo affect the efficiency of pig production; therefore, these variables should be particularly considered in order to increase the efficiency of somatic cell pig cloning.
        4,000원
        3.
        2020.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Advancing the estrous cycle of mares is an essential breeding strategy that is routinely conducted by Thoroughbred breeders to improve economic outcomes. For this purpose, Equilume light masks have been developed as an alternative to existing technologies such as artificial lighting or hormonal treatments because they are considered as valid as existing methods with additional animal welfare advantages. For example, with the Equilume light masks, horses can be let out into the pasture, whereas they have to be kept indoors during lighting treatment. Because the function of Equilume light mask on the estrous cycle of mares is influenced by environmental factors such as nutrition condition and temperature, Equilume light mask should be studied in various environments. The objective of the present study was thus to verify the effect of Equilume light masks on the onset of the estrous cycle in Thoroughbred mares in South Korea. Mares were randomly selected and separated into two groups at two Thoroughbred horse breeding farms. The mares in the treatment group were equipped with Equilume light masks from November 18 to February 10 the following year. The body condition, the number and size (> 35 mm) of uterine follicles, and the uterine horn score of the mares were assessed on January 6 and February 10. The body condition scores were not different between the two groups. The treatment with the Equilume light mask had no positive effects on developing follicles and the reproductive tract. In conclusion, the use of Equilume light masks did not influence the seasonal resumption of the estrus cycles in Thoroughbred mares in South Korea.
        4,000원
        4.
        2019.12 구독 인증기관 무료, 개인회원 유료
        본 연구는 붉바리 배란유도를 위해 다양한 호르몬과(ovaprim, pimozide, LHRHa, HCG)과 LHRHa 의 농도별 효과를 조사하였다. LHRHa는 50 μgkg-1, 100 μgkg-1, 150 μgkg-1, 200 μgkg-1의 농 도로 처리하였다. 호르몬은 등 근육에 주사하였으며, 조사 결과 LHRHa 단독, 그리고 LHRHa와 Pimozide를 혼합하여 투여했을 때 가장 효과적이었으며, 두 실험구 사이의 차이는 거의 없는 것으로 나타났다. 따라서 LHRHa를 단독으로 사용하는 것이 가장 효율적인 것으로 판단된다. 그리고 LHRHa를 다양한 농도로 처리하여 배란유도 효과를 조사한 결과 100 μgkg-1의 농도로 투여했을 때 가장 우수한 것으로 조사되었다.
        4,000원
        6.
        2018.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Ensuring timely ovulation concerning the service is valuable. A satisfactory conception rate can be achieved by making sure that ovulation occurs within 7-18 hours after artificial insemination (AI). Delayed ovulation is one of the disturbances commonly encountered in repeat breeding animals. Although demanding research, many studies have not been conducted. Therefore, we aimed to examine the relation between ovulation confirmation and conception rate in dairy cattle. The research findings showed that the signs of true estrus were bred 12 hours after the onset of estrus by AI in cattle. Also, the performance of AI on ovulation was confirmed by the presence of fluctuant Graafian follicles through rectal palpation. From the results, we confirmed that cow encountered delayed ovulation were bred again. The Conception rate in cows with confirmed ovulation was 51.9%, while for those without confirmed ovulation were 33.3%. In conclusion, the results indicate that ovulation confirmation will likely increase conception rate.
        4,000원
        7.
        2017.05 구독 인증기관·개인회원 무료
        Canine cloning have been succeeded for a decade. To obtain in vivo matured dog oocytes, Serum progesterone (P4) level were employed for ovulate determination. However, accuracy of P4 methods is not satisfied. The aim of this study was to compare both methods of serum estradiol (E2) and P4 on the accuracy of canine ovulation determination. Canine serum P4 and E2 concentration during both proestrus and estrus were detected. Correlation between accuracy of each method and environment temperature were analyzed. Following ovulation, oocytes were collected by surgery. As a result, higher percentage of mature oocytes was obtained when using E2 (56.43%) as compared to P4 (39.60%). Accuracy of P4 increased from spring (30.76%) to summer (47.92%) and decreased in autumn (37.50%) and winter (29.16%) gradually. Especially, E2 maintained about 50% to 65% whatever the season and temperature. Correlation analyze showed that dynamic of P4 accuracy highly correlated with environment temperate (Rp4=0.862) but E2 could not be affected by the temperature (RE2=0.199). To determine whether obtained oocytes by E2 method could be used for canine cloning, twenty canines were selected as oocyte donors, and two puppies were produced after somatic cell nuclear transfer(SCNT) and embryo transfer(ET) with the oocytes by E2 method. In conclusion, comparing to the P4 method, the E2 is an accuracy and reliable method for canine cloning.
        8.
        2017.05 구독 인증기관·개인회원 무료
        To obtain in vivo matured oocytes for dog cloning, serum progesterone (P4) level were employed for ovulate determination. Radioactive immunoassay (RIA) is a traditional serum hormone assay method with highly radioactivity. The aim of this study was to evaluate the reliability of RIA and to compare its canine serum P4 concentration determination accuracy to that of the electric chemiluminescence immunoassay (ECLI). To obtain in vivo matured oocytes for canine somatic cell nuclear transfer, serum P4 levels were accurately measured with both methods of RIA and ECLI. Although both methods detected similar P4 level before ovulation, the mean P4 concentration using ECLI was significantly higher than that using RIA from 3days before ovulation. Following ovulation, oocytes were collected by surgery, and a lower percentage of mature oocytes were observed using ECLI (39%) as compared to RIA (67%) if 4-8ng/ml of P4 were criteria for determination of ovulation. On other hand, high percentage of mature oocytes was observed using ECLI when 6–15 ng/mL of progesterone was criteria for ovulation determination. To determine whether in vivo oocytes obtained by ECLI method could be used for canine cloning, six canines were selected as oocyte donors and two puppies were produced after SCNT and embryo transfer. In conclusion, compared to the traditional RIA method, the ECLI method is a safe and reliable method for canine cloning.
        10.
        2015.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of the present study was to investigate the ovulation rate and its relationship to fertilization ability in Landrace, Durock and Crossbred pigs. Gilts were natural mated at a body weight of at least 120 kg under the same hormone treatment. Embryos were surgically collected 1 day after natural mating (Day 0). Embryos derived from in vivo-fertilized oocytes were cultured in medium PZM-3. The ovaries were examined and the pathological findings were recorded. The number of corpus hemorrhagicum was counted, and was assumed to equal the ovulation rate. There was no difference in the number of corpus hemorrhagicum (20.4, 28.8 and 23.2) and ovulation (13.5, 26.8 and 17.2) in the Landrace, Durock and Crossbred pigs. The two pronucleus formation was 76.0, 80.0 and 86.9%. The Day-7 embryos had blastocyst rates of 68.0, 75.0 and 73.9%. There was no difference in the number of total cells and apoptotic cells. In the future, more studies require determining relationships between ovulation and fertilization rate in different species of pigs.
        4,000원
        11.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Feline ovulation time after LH surge have not been defined because its LH surge is occurred by several times of coital vaginal induction and cat has relatively longer time between LH surge and ovulation compared with other mammalian species. This study was performed to investigate the feline ovulation time after LH surge that was induced by hCG injection for superovulation with PMSG. For superovulation, all cats were received an initial injection of PMSG (200 IU, i.m.) followed 80 hrs later with an injection of hCG (200 IU, i.m.). And then, sampling of both ovaries was surgically performed at each 6 different times (10, 18, 22, 26, 29, and 32 hrs) after hCG injection. Cumulus-oocyte-complexes (COCs) were collected from 2 sides of oviducts and ovaries were fixed for ovarian histology. Total 38 COCs were collected only at hCG 32 hrs and no COCs were shown at earlier 5 times. However, in the ovarian histology, corpus haemorrhagicum or corpus luteum was not shown in all groups including ovary at hCG 32 hrs that COCs were collected. In conclusion, it was suggested that feline ovulation was occurred at 29~32 hrs after LH surge and taken relatively long time for CL formation after ovulation.
        4,000원
        12.
        2013.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        It is generally accepted that chronic stress impairs female reproduction. It negatively affects ovarian function and the number of ovulated oocytes. Chronic stress lowers the number of retrieved oocytes. Ovarian follicular development is regulated by both pituitary-derived gonadotropins and intraovarian regulatory factors. The main corticosteroids are cortisol, cortisone, 11-deoxycortisol and corticosterone, cortisol being one of the most commonly used welfare and stress physiological indicator. In this study, we investigated the effect of cortisol level on progesterone patterns and ovulation in the dog. Cortisol and progesterone level of serum were analyzed by radioimmunoassay. The day of ovulation was considered as the day when serum progesterone concentration was 6.0∼8.0 ng/ml. In vivo dog oocytes were collected by flushing oviducts of mixed-breed bitches at three days after ovulation. We classified dogs as having group 1 (cortisol level, 0 ≤ or < 2 μg/dl), group 2 (corisol level, 2 ≤ or < 4 μg/dl), group 3 (cortisol level, 4 ≤ or < 6 μg/dl) and group 4 (cortisol level, 6 μg/dL ≤). The patterns of progesterone were not different in four cortisol groups. The average numbers of retrieved oocytes was not different in four cortisol groups. These results suggest that different cortisol levels on estrus dogs do not affect ovulation, number of ovulated oocytes and progesterone changes.
        4,000원
        14.
        2011.10 구독 인증기관·개인회원 무료
        Ovulation resembles a tissue remodeling process such as a blood coagulation. The present study was aimed to examine the involvement of tissue factor, a primary factor for extrinsic coagulation pathway, in the ovulation. Northern blot analysis revealed that mRNA levels of tissue factor and tissue factor pathway inhibitor 2 (TFPI-2) in the ovary were stimulated by human chorionic gonadotropin (hCG) treatment in surperovulation model, of immature rats. Real-time PCR analysis demonstrated that the expression of tissue factor and TFPI-2 was stimulated in granulosa and theca cells of preovulatory follicles, respectively. The induction of tissue factor mRNA was blocked by the progesterone receptor antagonist RU486. Tissue factor protein was not detected in the ovary by Western blot and immunohistochemical analysis due to the lack of a specific antibody. Interestingly, the levels of tissue factor and TFPI-2 mRNA were increased in the ovarian cells of rats induced ovarian hyperstimulation syndrome (OHSS) and in granulosa cells of OHSS patients undergiong in vitro fertilization. The present findings indicate the stimulation of tissue factor system during ovulation, and in OHSS patients, implicating the possible involvement of tissue factor system in OHSS.
        15.
        2011.10 구독 인증기관·개인회원 무료
        Ovulation resembles a tissue remodeling process such as a blood coagulation. The present study was aimed to examine the involvement of tissue factor, a primary factor for extrinsic coagulation pathway, in the ovulation. Northern blot analysis revealed that mRNA levels of tissue factor and tissue factor pathway inhibitor 2 (TFPI-2) in the ovary were stimulated by human chorionic gonadotropin (hCG) treatment in surperovulation model, of immature rats. Real-time PCR analysis demonstrated that the expression of tissue factor and TFPI-2 was stimulated in granulosa and theca cells of preovulatory follicles, respectively. The induction of tissue factor mRNA was blocked by the progesterone receptor antagonist RU486. Tissue factor protein was not detected in the ovary by Western blot and immunohistochemical analysis due to the lack of a specific antibody. Interestingly, the levels of tissue factor and TFPI-2 mRNA were increased in the ovarian cells of rats induced ovarian hyperstimulation syndrome (OHSS) and in granulosa cells of OHSS patients undergiong in vitro fertilization. The present findings indicate the stimulation of tissue factor system during ovulation, and in OHSS patients, implicating the possible involvement of tissue factor system in OHSS.
        16.
        2011.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Ovulation synchronization (ovsynch) has proved to increase the number of insemination in cattle by overcoming the problems of heat detection. The aim of this study was to do ovsynch in water buffaloes where heat detection is a major reproductive problem and to determine the conception rates after timed artificial insemination (TAI). Twenty cyclic buffaloes at 60 days postpartum were selected by examining 24 unobserved estrus buffaloes based on milk progesterone assay (progesterone concentration 1.0 ng/ml) from the Mymensingh district of Bangladesh. Ovsynch treatment regimen was started irrespective of the stage of estrous cycle. Gonadorelin (500 ) was injected intramuscularly at Day 0 followed by Alfaprostol (8 mg) at Day 7. A second injection of Gonadorelin was given at Day 9 and TAI was done with frozen semen from Mediterranean buffalo bulls at 16~20 hours of the second Gonadorelin injection. Milk progesterone ELISA at Day 10~12 post AI confirmed ovulation in 16 out of 20 (80%) buffaloes (progesterone concentration 1.0 ng/ml). High progesterone concentration ( 1.0 ng/ml) at Day 10~12 and Day 22~24 of AI showed pregnancy in six out of 20 (30%) buffaloes. Pregnancy was further confirmed by ultrasonography at Day 40 in these six buffaloes. In conclusion, ovsynch followed by TAI could be applied in cyclic buffaloes for overcoming the estrus detection problems; however, more studies are needed to increase the conception rate.
        4,000원
        17.
        2007.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 젖소 경산우와 미경산우의 다양한 발정 행동 특성과 배란 시간을 조사하기 위해 수행되었다. 공시된 89두 중 73두에서 배란이 일어났으며, 이 중 61두에서 발정 발현이 나타났다. 다양한 발정 행동은 투여 후 2일째부터 72시간 동안 육안 관찰하였으며, 배란 시간(4시간 간격으로 초음파 시험)과의 관계를 각각 조사하였다. 경산우의 발정 발현율은 외음부 냄새 맡기, 턱 비빔, 승가 및 승가 허용에서 각각 81%, 78%, 78% 및 56%로 나타
        4,000원
        18.
        2007.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 젖소의 발정 행동 징후에 따라 배란 시간을 예측하고 결정하기 위하여 발정의 다양한 행동 징후(승가, 승가허용, 외음부 냄새 맡기 및 턱비빔)와 배란 시간과의 관계에 대해 조사하였다 공시된 51두 중 37두에서 배란이 일어났으며, 이 중 28두에서 발정 발현이 나타났다. 발정 행동 징후는 주사 후 2일째부터 72시간 동안 육안 관찰하였으며 배란 시간(4시간 간격으로 초음파 검사)과의 관계를 각각 조사하였다. 발정 행동별 발정 발현율은 외음부 냄
        4,000원
        20.
        2006.09 구독 인증기관 무료, 개인회원 유료
        본 연구는 유우 사육 농가에서 배란동기화법(OVSYNCH)의 활용시 수태율에 미치는 영향을 검토하였다. 그 결과, 유우의 정상 번식우(15/23, 65%)와 번식 장애우(5/10, 50%)의 수태율 비교에서는 정상번식우가 수태율이 높게 나타났지만 유의차는 인정되지 않았다. 그러나 유우 경산우의 산유량에 따른 수태율 비교에서는 1일 산유량이 30~35 kg 이상인 유우군에서 배란동기화 처리시 20~25kg인 유우군에 비해 유의적으로 높은 수태율을 나타냈다(p<0.05). 또한 유우 경산우의 산차수에 따른 수태율 비교에서는 1산차의 시험우군이 3산차군에 비해 유의적으로 높은 수태율을 나타냈지만(p<0.05) 산차수 증가에 따른 수태율은 일정한 경향을 나타내지 않았다. 본 연구의 결과로부터, 배란동기화 방법을 유우의 다두사육 농가에서 실제로 이용할 경우, 우유 생산이 가능한 정상번식우에서 효과적이었으며, 특히 1일 산유량이 많은 유우에서 높은 수태율을 얻을 수 있었다. 한편 앞으로의 연구를 통해 개선된 배란동기화법을 이용한다면 호르몬 불균형으로 초래된 번식 장애우의 번식 능력 회복과 함께 향상된 수태율을 얻을 수 있는 효과적인 방법으로 농가에서도 간편하게 이용될 수 있을 것으로 평가된다.
        3,000원
        1 2 3