• Asian-Australasian Journal of Animal Sciences
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• 제32권11호
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• pp.1673-1685
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• 2019

Objective: To evaluate the efficacy of treatments based on gonadotrophin-releasing hormone (GnRH), GnRH-prostaglandin $F2{\alpha}$ ($PGF2{\alpha}$), and/or intense exposure to novel rams to induce fertile estrus without the use of steroid hormones in seasonally anestrous Suffolk ewes. Methods: In the first experiment, ewes were treated with one injection of GnRH, two injections of GnRH administered 7 days apart, or a sequence of GnRH-$PGF2{\alpha}$-GnRH (GPG). In the second experiment anestrous ewes were exposed, for 36 days starting on the day of weaning, to groups of four rams of three different breeds that were alternated every day. Besides exposure to the male effect (ME), the ewes were injected with saline solution (ME group, n = 20), with GnRH (ME-GnRH group, n = 20) or with a sequence of GnRH-$PGF2{\alpha}$-GnRH (ME-GPG group, n = 20). The rams used for male-effect were fitted with aprons to prevent mating, and ewes detected in estrus were bred to selected fertile rams. Ovarian activity was monitored by progesterone determinations in both experiments. Results: In the first experiment sustained induction of ovarian activity was not achieved and no ewe was detected in estrus. In the second experiment induction of sustained ovarian activity was achieved in all groups. Most of the ewes were detected in estrus, 76.7% of the ewes were mated during a 36-d breeding period and 71.7% of all the ewes became pregnant during that period. No significant differences between groups were found for any of these variables. However, estrus detection efficiency was higher in the ME-GnRH group than in the ME group (p<0.05). Conclusion: An intense male-effect, that included the continuous presence and frequent alternation of several rams of different breeds, was sufficient to induce ovarian activity and fertile estrus in Suffolk ewes during the period of deep anestrus without the use of hormones, although addition of GnRH improved the efficiency of estrus detection.

• 한국수정란이식학회지
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• 제24권3호
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• pp.169-176
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• 2009

Domestic bitches are non-seasonally monoestrus; spontaneously ovulate only once or twice occurs at anytime of the year. Estrus induction has been applied infrequent estrus, misleading ovulation, mating difficulties, failure to conceive after normal mating, pregnancy failure and biological research. Protocol of estrus induction which included variable hormones such as FSH, GnRH, and PMSG have been applied for the last decades. Recently, Bromocriptine, one of anti-prolatin/dopamine agonist has been occasionally applied for estrus induction. The study was carried out to investigate the effective method for the induction of estrus in bitches using different hormone treatments, and the initiation time of estrus from hormone treatment by assessments of cytological observation and blood plasma progesterone concentration. A total of 54 bitches on anestrus were selected for the study and divided randomly into 8 treatment groups as follow. Control, natural estrus; FSH (L), FSH (1.5 mg/kg, twice a day, $Falltrophin^{(R)}$, Vetrepharm); FSH (H), FSH (3.0 mg/kg, twice a day); GnRH+FSH, GnRH (5 ug/kg, once first day, $GNADON^{(R)}$, Dongbang)+FSH (3 mg/kg, SID); PMSG, PMSG (50 IU/kg, every third day $FOLLIGON^{(R)}$, Intevet); GnRH+PMSG, GnRH (5 ug/kg, only first day)+PMSG (50 IU/kg, every third day); GnRH, GnRH (5 ug/kg, only first day); Bromocriptine, bromocriptine (0.3 mg/kg, SID, $Parlodel^{(R)}$, Novartis). The bitches were evaluated clinical sign, cytological exam and $OVUCHECK^{(R)}$ Premate for assessment of estrus induction. Estrus induction rates were significantly (P<0.05) higher in GnRH+PMSG (100%) compared to others. PMSG and GnRH+PMGS (87.5 and 100%) and Bromocriptine (77.8%) were higher than others except GnRH+PMSG. Analysis of vaginal smear has proved to be effective a correct assessment of estrus induction with assay of progesterone concentration by $OVUCHECK^{(R)}$ Premate. Proestrus initiated by the $6^{th}$ after induction in most case. In conclusion, bromocriptine is an effective drug for estrus induction in bitches and assay of progesterone concentration by $OVUCHECK^{(R)}$ Premate with examination of vaginal smear that should be useful to detection of estrus induction of estrus induced bitches.

• Asian-Australasian Journal of Animal Sciences
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• 제33권7호
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• pp.1138-1147
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• 2020

Objective: A study was made investigate factors affecting body surface temperature changes after weaning in sows, whether these can be used to aid detection of natural estrus and how they relate to subsequent reproductive performance. Methods: A total of 132 sows were selected during summer from a breeding farm, with mean parity of 3.6±2.3 and 28.5±0.9 days lactation length. Four daily measurements (6:00, 8:00, 16:00, and 18:00) of vulva (VST), udder (UST), ear base and central back skin temperatures for individual sows were taken by an infrared thermometer, continuing up to 8 days post weaning. Results: The VST obtained from sows showing estrus at 4 days post-weaning (4DPW), 5DPW, and 6DPW showed a peak at the fourth day post-weaning, but then started to decrease. The VST of sows not detected in standing heat (NDPW) remained at a lower level during the experiment, but UST was increased soon after weaning. The VST-UST temperature differences during daytime of sows that were showing behavioural standing heat on 4DPW, 5DPW, 6DPW, and 7DPW were 0.46℃±0.123℃, 0.71℃±0.124℃, 0.66℃ ±0.171℃, and 0.58℃±0.223℃, respectively. The NDPW sows had the highest UST observed, but also the lowest VST so that a more negative value of temperature difference (-0.31℃) was seen during first few days post-weaning. A total of 119 sows were observed to show standing heat and were bred. The later the estrus, the smaller the litter size (p = 0.005). Conclusion: Sows which did not show behavior indicative of stable standing heat after weaning had a VST which remained at a lower level, but the UST increased soon after weaning. Therefore, for sow heat detection under field conditions, the changes of VST and UST and difference between the two should be considered together to increase the accuracy of detection.

• 한국동물생명공학회지
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• 제38권4호
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• pp.215-224
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• 2023

Background: Reproductive management practices play crucial roles to maximize the reproductive performance of cows, and thus contribute to farm profitability. We aimed to assess the reproductive management of cows currently practiced in the dairy farms in an urban farming system. Methods: A total of 62 dairy farms were randomly selected considering all size of farms such as small (1-5 cattle), medium (6-20 cattle) and large farms (> 20 cattle) from selected areas of Dhaka city in Bangladesh. The reproductive management-related parameters viz. estrus detection, breeding method, pregnancy diagnosis, dry cow and parturition management, vaccination and treatment of reproductive problems etc. were obtained in a pre-defined questionnaire during the farm visit. Results: The visual observation method was only used (100.0%; 62/62) for estrus detection irrespective of size of the farms; while farmers observed cows for estrus 4-5 times a day, but only for 20-60 seconds each time. Regardless of farm size, 89.0% (55/62) farms used artificial insemination (AI) for breeding the cows. Intriguingly, all farms (100.0%) routinely checked the cows for pregnancy at 35-40 days post-breeding using rectal palpation technique by registered veterinarian. However, only 6.5% (4/62) farms practiced dry cow management. Notably, all farms (100.0%) provided nutritional supplements (Vit D, Ca and P) during late gestation. However, proper hygiene and cleanliness during parturition was not practiced in 77.4% (48/62) farms; even though 96.7% (60/62) farms treated cows by registered veterinarian for parturition-related problems. Conclusions: While farmers used AI service for breeding and timely check their cows for pregnancy; however, they need to increase observation time (30 minutes/ observation, twice in a day: early morning and early night) for estrus detection, consider dry cow management and ensure hygienic parturition for maximizing production.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.185-188
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• 2003

Data on the use of breeding records of dairy cattle farm of Fenghuang-shan in Chengdu areas during a period of six years is systematically analyzed. The results show that Holstein heifers have their 1st estrus at an average age of $513.6{\pm}46.7$ d which is not related to the calving season. Estrus mostly occurs in the months with mild ambient temperature (March, April, May, November and December). There is a very poor rate of estrus detection; only 30.0% successive estrus is observed within 24 d, 29.3% within 25-48 d, 40.6% over 48 d. The average number of insemination per conception is 1.50 for heifers and 1.74 for cows, but conception rate (CR) is lower in the relatively warm months (July, August and September) ranged from 48.1% to 51.9% compared with 58.1% to 68.5% in other months. High temperature is the most important factor affecting fertilization in warm months, but neither did CR decline immediately with the increased air temperature in June, nor did it increase immediately with the declined air temperature in September. Post partum anestrous period is $119.5{\pm}60.5$ d. The average interval from calving to conception is $159.4{\pm}85.6$ d with only 19.8% of the cows conceived within 85 d of calving. Cows with high milk yield have longer acyclic periods and lower conception rates. Improvement of efficient managements must be a precedent condition in Chengdu areas.

• 한국수정란이식학회지
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• 제29권1호
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• pp.43-50
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• 2014

To describe the macroscopic anatomy and ovarian-physiological difference of the genital organs of the female Korean water deer, organs from captured animals in a wild area of Korea were dissected. The ovary of estrus group was about $1.10{\pm}0.02mm$ long and weighed about $0.50{\pm}0.02g$. And pregnant group was about $1.3{\pm}0.10mm$ long and weighed about $0.40{\pm}0.05g$. And the crowns of corpora lutea were found in the estrus group, but we couldn't find crowns at the pregnant group. Especially, the estrus ovaries tended (p=0.04) to be heavier than the ovaries during pregnancy. The MMP-9 activity was higher at the Graafian follicles of pregnant group than that in estrus group. However, with regard to follicles of estrus group, MMP-2 level was higher than that in pregnant group. Furthermore, apoptosis detection marker (Casp-3) was highly expressed in Graafian follicle of the pregnant group and the corpora lutea of estrus group. Thus, the differential expression of MMPs observed in this study suggests that the reflected the mechanisms underlying of monovulatory in estrus and/or pregnancy. Our results may be very useful as it provides with information that may be considered for the development of reproductive biotechnologies in endangered animals.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2001년도 동계 학술대회 논문집
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• pp.400-405
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.697-700
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• 2001

A prolonged farrowing interval is common on small farms in Nepal and may be attributable to the absence of boar contact at the time of weaning. To examine whether synthetic boar pheromone spray might be of value to aid the stimulation and detection of estrus, 30 village farms, each with a single sow, were recruited into a field study. All sows entered the study on final weaning from their first lactation at 56 days post partum. For 13 treatment sows, a boar pheromone spray (SOA, Intervet, Boxmeer, The Netherlands) was applied each day after weaning whilst 17 other sows did not receive any stimulus (negative control). When estrous was detected by the farmer, sows were taken to the nearest boar for service. There was a significantly shorter weaning to re-mating interval for treatment sows (42.9 V 82.2 day, p<0.05), with a significantly higher proportion of treatment sows rebred by day 60 after weaning (p=0.024, Fishers Test). It is concluded that use of boar pheromones can improve reproductive efficiency of sows kept under Nepalese village conditions.

• 한국산학기술학회논문지
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• 제21권11호
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• pp.825-832
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• 2020

소의 발정을 정확하게 탐지하는 것은 번식률을 향상시키는데 매우 중요하며, 현재 발정기 소의 행동 특성들을 활용한 다양한 발정탐지 기술들이 개발되고 있다. 본 연구에서는 우리나라 고유품종인 한우의 발정기 행동변화에 대한 기초자료를 수집하기 위하여 발정기 한우의 활동량, 승가행동 및 발성횟수 등에 대해 조사하였다. 총 4두의 한우 경산우를 공시하였으며, 각 개체별로 목걸이형 생체정보 수집장치(Bio-telemetry device)를 설치하였다. 발정이 확인된 날을 포함하여 발정 2일 전부터 발정 후 3일까지 총 6일간 이동거리, 승가행동 및 발성음을 비교 분석한 결과, 발정 2일 전부터 발정 1일 전까지 이동거리의 변화가 거의 없었으나, 발정이 확인된 당일부터 급격히 증가하였으며(p<0.001), 발정 후 1일 후부터는 서서히 감소하기 시작하였다. 또한 소의 활동량이 낮보다 밤 시간대에 더 활발한 것으로 나타났다. 반면, 승가행동은 발정 2일 전부터 발생빈도가 점점 증가하기 시작하여 발정 당일에 가장 높게 나타났으며(p<0.01), 전 시간대에 걸쳐서 불특정하게 나타나는 것을 확인할 수 있었다. 한편, 발성음의 경우 발정 당일에는 발성음 빈도가 증가하는 경향을 보였으나 유의적인 차이가 없었다(p>0.05). 발정기 한우의 승가행동은 발정 2일전부터 시작해서 발정 당일에 가장 높게 나타나는 특성이 있기 때문에 활동량보다 우선적으로 발정을 예측할 수 있는 지표로써 활용 가능할 것으로 보이며, 이 두 가지 지표를 함께 활용한다면 한우의 발정탐지율을 향상시키는데 도움이 될 것으로 판단된다. 발정탐지율을 높이기 위해서는 한우의 발정기 행동 특성과 관련하여 더욱 다양한 정보들이 필요할 것이다.

• 한국임상수의학회지
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• 제19권4호
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• pp.418-425
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• 2002

Estrus was induced in 13 anestrus Korea Jin-do bitches by intramuscular injection of pregnant mare serum gonadotropin (PMSG) in a dose of 500 lU once daily for ten consecutive days, followed by an additional single intraveneous injection of 1,000 lU of human chorionic gonadotropin (hCG) on the tenth day. Day-changes of vaginal epithelial cells during the hormone treatment were investigated in each experimental bitches and compared with the those of spontaneous estrus bitches. The first days of vulval bleeding and male acceptance after PMSG treatment were on Day 6.0$\pm$ 1.5 (mean$\pm$ SD) and Day 9.0$\pm$ 1.9, respectively. And in all of 13 bitches, vulval swelling and perineal reflex were shown. The mean durations of proestrus and estrus were 2.9$\pm$ 1.4 (mean$\pm$ SD, range ; 1-6) and 11.5: 1.7 (range ; 8-14) days, respectively, that is, duration of proestrus was significantly shorter than that of the spontneous estrous bitches but duration of estrus was longer than that of the spontaneous estrous bitches. Characteristic features of vaginal cytology during the estrous cycle were the high proportions of large intermediate cell, superficial cell, anuclear cell and erythrocyte in proestrus, superficial cell and anuclear cell in estrus and parabasal cell, small intermediate, large intermediate cell, and leukocyte in diestrus, respectively. The comification index (Cl) was significantly high proportion in proestrus and estrus, when Day 0 was timed from the first day of male acceptance, the Cl was first increased above 80% on Day 0 and maintained above 80% until Day 0 to Day 5 during 6 days and showed a peak on Day 2. Also it was maintained above 90% until Day 2 to Day 3 during 2 days. These results indicated that all 13 ekperimental bitches showed positive estrus detection by the estrus behavior and vaginal smear test after treated with PMSG and hCC. It suggested that vaginal cytology was used to estimate the optimal mating and ovulation time, in consideration of the day when the Cl was maintained above 80% in estrus-induced Korea Jin-do bitches.