• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1268-1273
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• 2003

Sixty postpartum lactating Friesian cows in 3 treatments at a commercial dairy farm were used to study the effect of using progesterone supplementation with GnRH and PGF2$\alpha$ synchronization with and without timed AI on fertility during summer. Cows in treatment1($Tr_1$) and treatment2 ($Tr_1$) were fitted with progesterone releasing intravaginal device (PRID) device and injected with 10 g GnRH agonist on $51{\pm}3$ d postpartum (pp). Seven days later, PRID was removed and cows received 25 mg PGF2$\alpha$. Two days later, $Tr_1$ cows received another injection of 10 g GnRH and timed AI 16-20 h later. Control cows received only 25 mg PGF2$\alpha$ $58{\pm}3d\;pp$. $Tr_2$ and control cows were AI at detected estrus. Serum progesterone for all cows was determined on days of injection, AI and 21, 23 and 28 d postinsemination. Pregnancy rates from first AI based on serum P4 concentrations on d 21, 23 and 28 postinsemination (50, 40 and 35%) and that based on rectal palpation 40-45 d postinsemination (30, 15 and 15% for $Tr_1$, $Tr_2$ and control cows, respectively) did not differ among the three groups. Whereas, pregnancy rate at 120 d pp for $Tr_1$ (65%) was higher (p<0.05) than that in $Tr_2$ (30%) or control (30%). The overall pregnancy rate was not significantly different (90, 90 and 75% for $Tr_1$, $Tr_2$ and control, respectively). Days open for cows in $Tr_1$ ($100.3{\pm}9$) was less (p<0.03) than that in $Tr_2$ ($130.9{\pm}9$) or control ($135.1{\pm}10$). Results indicate that using PRID device with Ovsynch program had significantly increased pregnancy rate and decreased days open compared to AI at detected estrus after synchronization with GnRH, PRID and PGF2$\alpha$ or synchronization with one injection of PGF2$\alpha$.

• 한국수정란이식학회지
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• 제31권3호
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• pp.255-260
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• 2016

The aim of this study is to evaluate the effects of vitamin or mineral supplements on the conception rates of dairy heifers when replacing the last injection of GnRH with hCG in ovsynch protocol (experiment 1) and also to investigate whether the estrus synchronization treatment in the heifer stage affects the conception rates after $1^{st}$ parturition (experiment 2). In experiment 1, 50 heifers were randomly assigned into 3 groups: 20 heifers each in groups 1 and 2, and 10 in group 3. All three groups were treated with an intramuscular injection of GnRH on day 0 (day 0 = the day of program start), $PGF_{2{\alpha}}$ on day 7 and hCG on day 9, and were inseminated on day 10, 12~16h after hCG injection. In group 1 (vitamin group), the heifers were treated with an intramuscular injection of 5 ml of vitamin-ADE $500^{(R)}$, and group 2 (mineral group) was treated twice with an intramuscular injection of 30 ml of mineral supplement-LAPTOVET$^{(R)}$ on a one-week interval beginning on the day of hormone treatment (day 0 and day 7 respectively). Group 3 (control) was treated only with hormones. Pregnancy diagnosis was performed by ultrasonography through a rectal probe. First service conception rates (FSCR) and average services per conception (ASPC) were recorded for all subjects. Of the total 50 heifers, 6 (2 in group 1, 3 in group 2, and 1 in group 3) heifers were eliminated due to accidents during experiment 1. FSCRs were 58.8% (10/17), 66.7% (12/18) and 44.4% (4/9) in groups 1, 2 and 3, respectively. ASPCs were $1.53{\pm}0.72$, $1.27{\pm}0.59$ and $1.63{\pm}0.74$ in groups 1, 2 and 3, respectively. Although there were no significant difference between the groups, relatively good results (higher FSCR and lower ASPC) were obtained in both group 1 and 2. In experiment 2, 11 primiparous cows from group 2 of experiment 1 in heifer stage which had been treated both with the hormones for estrus synchronizing and mineral supplements (ES group), and 12 primiparous cows treated only with minerals (non-ES group) were compared to examine the effects of estrus synchronization program on conception rates after $1^{st}$ parturition. Following the examination, postpartum ASPCs were $1.55{\pm}0.82$ and $2.17{\pm}1.47$ in ES group and non-ES group, respectively. The postpartum average days open (ADO) were $116{\pm}56$ and $197{\pm}93$ in ES group and non-ES group, respectively. Although there were no significant difference between the two groups, desirable results (lower ASPC and shorter ADO) were found in ES group after $1^{st}$ parturiton. In conclusion, experiment 1 indicates that vitamin or mineral supplement with ovsynch protocol may have some positive effect on FSCR and ASPC of dairy heifers, and in experiment 2, ES program in heifer stage had a positive effect on ASPC and ADO following $1^{st}$ parturition.

• 한국수정란이식학회지
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• 제23권2호
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• pp.109-114
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• 2008

This study examined pregnancy and fetal loss rates according to different estrus synchronization protocols and injection of gonadotropin releasing hormone (GnRH) after transfer of Korean Native Cattle embryos to Holstein recipients. In Experiment 1, recipients received no treatment (Control, n = 119); two injections of prostaglandin$F_{2{\alpha}}$ ($PGF_{2{\alpha}}$ ) 11 days apart (PGF group, n = 120); GnRH (day 0)-$PGF_{2{\alpha}}$ (day 7)-GnRH (day 9) (Ovsynch group, n = 120); and CIDR (day 0)-$PGF_{2{\alpha}}$ and CIDR removal (day 7)-GnRH (day 9) (CIDR group, n = 110). In Experiment 2, the control group was received no treatment of GnRH. The treatment groups were received GnRH at embryo transfer (ET) (day 0), 7 days later, 14 days later, ET and 7 days later, 7 and 14 days later, or ET, 7 and 14 days later. Recipients were assigned to treatment randomly and received two in vitro produced blastocysts. Pregnancy was diagnosed at day 60 by palpation per rectum. Fetal loss to term was determined by palpation every 90 days thereafter. In Experiment 1, the pregnancy rate in the CIDR group (59.1%) were higher than in the Control group (42.0%) (p<0.01); fetal loss rates were similar for all groups (12.0 to 18.5%). In Experiment 2, the pregnancy rate in Day 0+7+14 group was higher (60.2%) than the control (40.2%) (p<0.01) and resulted in a lower fetal loss (p<0.05) than the control (4.6 vs. 11.4%). There were no significant difference between other treatment and the control (p>0.05). These results show that pregnancy rates of bovine embryos can be enhanced by CIDR insertion or GnRH $3{\times}$ treatment. Additionally, fetal loss may be reduced with GnRH treatment after ET.

• 한국수정란이식학회지
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• 제18권2호
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• pp.115-124
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• 2003

무발정 증상을 보이는 젖소 65두를 대상으로 몇 가지 호르몬 처리기법을 사용하여 소의 번식효율 향상시키고자 본 실험을 수행하였다. Group 1. Ovsynch program (GnRH-PGF$_2$ a /PGF$_2$ a/GnRH), Group 2. Two plus Two program (GnRH-PGF$_2$ a /PGF$_2$ a/GnRH), Group 3. progesterone implant (CIDR)-GnRH/PGF$_2$ a/PGF$_2$ a/GnRH과 Group 4. (Follicular rupture-progesterone implant-GnRH/ PGF$_2$ a/PGF$_2$ a/GnRH)로 구분하고 최종 GnRH 처지 후 발정 유도율, 발정유도시간, 임신율, 유산율, 인공수정 후 60일까지의 임신율을 조사하여 다음과 같은 결론을 얻었다. 1. 발정 유도율은 Group 1, 2, 3에서는 각기67%, 75%, 70%로서 비슷하게 나타났으나, Group 4에서는 86%로서 유의적(P＜0.05)으로 높은 발정율을 나타내었다. 2. 발정 유도 시간은 progesterone implant를 사용한 Group 3과 Group 4는 각각 24, 23시간으로 발정유도 시간을 단축시키는데 효과가 있었다. 3. 각 호르몬 투여 임신율은 progesterone implant를 사용한 Group 3과 Group 4가 75%, 85%로서 사용하지 않은 Group 1과 Group 2보다 유의적(P<0.05)으로 높은 임신율을 나타내었다. 4. 임신 49일까지의 유산율은 Group 4가 5.9%로 낮은 유산율을 보였다. 이상의 실험결과를 종합하면 무발정우에서 각종 호르몬을 투여하기 전에 난소를 확인하여 폐쇄 난포가 있는 것은 폐쇄난포를 제거하고 progesterone implant 제제인 CIDR를 질내에 장착하는 것이 무발정우의 발정유기 및 수태율 향상에 효과적이라고 사료된다.

• 한국수정란이식학회지
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• 제20권2호
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• pp.177-184
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• 2005

본 연구는 정상 및 저수태 한우에 rbST를 투여하였을 때 수태 및 분만율에 미치는 영향을 조사하기 위하여 수행하였다. 시험축은 성빈 한우 383두와 임상적으로는 정상이나 3회 이상 수정시켜도 수태가 되지 않는 저수태 한우 79두, 총 462두를 시험에 공시하였다. 실험을 수행하기 위한 시험구 배치는 5개의 처리구, 즉 T1(무처리, 2ml의 생리 식염수), T2(rbST 250mg 수정시 1회 미근부에 투여), T3(rbST 250mg: 수정시 및 수정후 $10\~14$일째 2회 투여), T4(rbST 500 mg: 수정시 1회 투여) 및 T5(rbST 500mg: 수정시 및 수정후 $10\~14$일째 2회 투여)로 나누어 시험을 실시하였다. 그리고 호르몬과 병행 처리구는 Day 0일에 GnRH 100 ug/cow를 견갑부에 피하주사하고 Day 7일째 $PGF_2{\alpha}\;25mg/cow$를 주사하여 황체를 퇴행시키고, Day 9일째 GnRH 100ug/cow를 주사하여 배란 동기화를 유도하여 시험에 공시하였다. 1. 정상 한우에 인공수정시 rbST를 T1, T2, T3, T4 및 T5로 처리하였을 때, 1회 수정 수태율은 대조구$(52.4\pm9.72\%)$에 비하여 $T2(67.5\pm18.48\%)$에서 높은 것으로 나타났고, 저수태우에서는 대조구$(39.3\pm12.89\%)$보다 $T4(63.3\pm5.77\%)$에서 유의적으로 높은 수태율을 나타냈다.(p<0.05). 또한, 정상 한우의 분만율에 있어서는 처리구간 유의적인 차이가 인정되지 않았지만, 저수태우에서는 $T4(46.7\pm11.55\%)$에서 유의적으로 높은 성적을 나타냈다(p<0.05). 2. Ovsynch 방법으로 발정을 유기하여 인공수정시 rbST를 T1, T2, T3, T4 및 T5로 처리하였을 때, 1회 수정 수태율은 대조구에 비하여 T2에서 $12.5\%$가 높은 것으로 나타났고, 저수태우에서는 $T4(80.0\%)$에서 유의적으로 높은 수태 율을 나타냈다(p<0.05). 3. 정상 한우에 인공수정시 rbST를 T1, T2, T3, T4 및 T5로 각기 처리하였을 때, 임신 기간은 평균 $282.7\~284.8$일이었고, 또한 생시체중의 비교는 평균 $25.1\~25.9kg$으로서 처리 구간 유사한 결과를 보였다. 그러나, 송아지의 암수 성비는 T4 처리구(18두 vs. 9두)를 제외한 모든 처리구에서 유사한 경향을 보였다. 그리고, 저수태 한우의 평균 임신 기간은 $280.4\~289.3$일로서 정상우와 비교했을 때 비슷한 결과를 보였고, 또한 생시 체중의 조사 결과에서도 평균 체중이 $23.0\~26.6kg$으로서 각 처리구간에도 유의성은 없었다. 송아지의 암$\cdot$수의 성비는 T4 처리구(2두 vs. 8두)를 제외한 모든 처리구에서 유사하게 나타났다. 결론적으로, 본 연구에서는 정상 및 저수태 성빈 한우에 rbST를 투여한 후 수태율과 분만율을 조사한 결과 인공수정시 정상우에서는 rbST를 250mg 1회 투여, 그리고 저수태 한우에 있어서는 rbST를 500mg을 인공수정시 1회 투여하였을 때가 다른 처리구에서 보다 우수한 결과를 나타내었다. 따라서 인공수정시 일정량의 rbST투여는 한우의 수태 및 분만율을 향상시키는 것으로 사료된다.