번식돈의 생리와 효율적인 사양관리

박충생,Park, Chung-Saeng 대한양돈협회 1988 養豚 Vol.10 No.9

돼지 인공수정기술의 실용화

박충생,Park, Chung-Saeng 대한양돈협회 1993 養豚 Vol.15 No.11

신기술-돼지 유기분만에 관한 최근 연구 동향

박충생,Park, Chung-Saeng 대한양돈협회 1992 養豚 Vol.14 No.9

젖소의 초음파 유도 채란율에 대한 FSH 전처리 효과의 비교

박충생,조성근,이정규,강태영,박성재,공일근,최민철,Park, Chung-Saeng,Jo, Seong-Geun,Lee, Jeong-Gyu,Gang, Tae-Yeong,Park, Seong-Jae,Gong, Il-Geun,Choe, Min-Cheol 한국동물번식학회 1997 Reproductive & developmental biology Vol.21 No.2

Ultrasound-guided follicular aspiration was performed in Holstein heifers once weekly with or without pretreatment of single or multiple decreasing doses using a total of 400 mg FSH. Oocytes were aspirated with a 6.5 MHz convex-array ultrasound trasducer designed for intravaginal use. All the visible follicles larger than 4 mm in diameter were punctured with a 17 gauge, 55 cm needle at each aspiration session and the follicular fluids containing oocytes were obtained by vacuum suction. The results obtained were as follows: As a preliminary experiment, the recovery rates of folicular oocytes by ultrasound-guided aspiration from the isolated ovaries of Korean native cows were compared between suction methods using manual syringe or vacuum pump. The recovery rate of oocytes using vacuum pump (80.7%) was significantly (P<0.05) higher than that using manual syringe (47.1%). The follicles were counted by their size in diameter with ultrasound image, and recovery rates and grades of follicular oocytes collected by ultrasound-guided aspiration were investigated in Holstein heifers pretreated with or without FSH. A group of heifiers were injected with multiple decreasing doses (twice a day for 3 days) of a total of 400 mg FSH. The other 2 groups were injected with a single dose of 400 mg FSH mixed with 25% PVP. Ultrasound observation of follicle population and/or ultrasound-guided transvaginal oocyte aspiration were performed 12 hrs following the last FSH injection in the multiple dose group, and 48 or 60 hrs after FSH injection in the single dose groups. Most of the visible follicles had small size of less than 3 mm in diameter in unstimulated heifers (71.0%), but medium size in all the heifers treated with FSH. (70.5 to 92.8%). The number of OPU follicles per session (4.6$\pm$1.9) were much less, compared to the vilsible follicle counts (9.7$\pm$2.2), in the nustimulated heifers due to the small dominant follicles. Among 4 goups of heifers the most visible as well as OPU follicles were observed in the heifers at 60 hrs following treatment of a single dose of 400 mg FSH (21.2$\pm$2.3 and 21.0$\pm$2.0), and the differences in both the follicle counts between the groups was found significant (P<0.05) The rates of oocyte recovery from the follicles by ultrasound-guilded aspiration were varied 46.3 to 75.0% in the heifers unstimulated and treated with a single dose of 400 mg FSH, but the group difference was not significant. The number of recovered oocytes per session a, pp.ared to be highest at aspiration at 60 hrs following single FSH (10.6$\pm$2.2) than at aspiration at 48 hrs after single FSH (7.8$\pm$2.7) or in the unstimulated heifers (3.4$\pm$3.0). The proportion of grade I and II oocytes to all oocytes collected was varied 31.8 to 64.0% between the groups. However, there was found no significant difference in both the number of oocytes recovered per session and the percentage and the percentage of grade I and II oocytes. From the above results it was concluded that the more oocytes of superior quality might be recovered economically by ultrasound-guided aspiration at 60 hrs following the pretreatment of a single dose of 400 mg FSH and by suction using a vacuum pump system of about negative pressure of 75 to 85 mmHg.

젖소에 있어서 요인별 후산정체 발생율과 번식효율

정기화(K . H . Chung),박상문(S . M . Park),곽대오(D . O . Kwack),박충생(C . S . Park) 한국축산학회 1991 한국축산학회지 Vol.33 No.6

A field experiment was performed to investigate the cause of retained placenta by season gestation length parity and sex of calf. and to determine the effect of placenta retention on the subsequent reproduction. days to first service days open and services per conception were evaluate in Holstein dairy cows. The cows which did not expell their placenta until 12 hours post-Parturient were termed as cow of Placenta retention. The time for placenta release was caleulated in the normal cows without retained placenta. The results obtained in these studies were summarized as follows; 1. The mean incidence of retained placenta was 24.4% in a total of 377 cows examined. Incidence of retained placenta was lowest in autumn calving cows(18.4%). in cows having longer than 286 days of gestation(20.0%), in 1st caking cows(14.7%) and in male calving but highest in summer calving(35.7%), in cows having shorter than 276 days of gestation(31.6%). in the 5th calving cows(28.2%) and in female calving although there were not significant differences between the respective groups. Birth weight of calves did not significantly affect the incidence of retained placenta Embryo transferred and artificial inseminated cows showed placenta retention of 33.3% and 23.9% respectively. with no significantly difference between both groups. 2. The times for placenta release in winter calving cows were significantly (P$lt; 0.05) longer than in spring and summer calving cows he 6.5±0.2 hours. but the gestation length, parity and sex of call were not found significant factors on incidence of placenta retention. 3. The period from calving to first service was significantly(p$lt; 0.01) longer in spring calving cows than autumn or winter calving ones. and also significantly(P$lt; 0.05) longer in the cows of 3rd parity than in tile cows of the 1st. 2nd, 6th and over parity. The results on days open and the services per conception showed significantly(p$lt; 0.111) lower reproductive performance in the cows of 4th parity but not significantly affected by gestation length or sex of calf. From these results. it seem to be no direct relationship between incidence of retained placenta and reproductive performance

Silver Nitrate 용액의 정소내 주입에 의한 돈의 거세효과에 관한 연구

강양수(Y . S . Kang),박충생(C . S . Park),정현승(H . S . Chung) 한국축산학회 1993 한국축산학회지 Vol.35 No.6

In order to develop a new chemical castration method in pigs, the effects of intratesticular injection of the various volumes and concentrations of AgNO₃ solution with or without lactic acid on the testicular atropy and their effects on body growth, body temperature and blood siver content were determined. The effects of castration on the daily gain of body weight and backfat thickness were also determined. These chemical solutions were injected to testes of a total of 32 suckling pigs. The results obtained were as follows. The size of scrotal testis was significantly (p$lt;0.05) increased by swelling up to 4 days and then decreased from 5 days after intratesticular injection of 1 or 2 ㎖ of 0.1, 0.5, 1.0 or 5.0% AgNO₃ solution with or without 88 part of lactic acid. The testes were fully atropied at 14 and 21 days after intratesticular injection of 1 or 2 ㎖ of 5% AgNO₃ solution without and with 88 part of lactic acid. However. The testes were not successfully atropied after intratesticular injection of 1 or 2 ㎖ of 0.1 or 0.5% AgNO₃ or 1 ㎖ of 1.0% AgNO₃ solution. These results were reconfirmed by autopsy at 170 days of age. Compared with the data of controls, there were no significant (p$gt;0.05) differences in the growth rate and body temperatures of pigs up to 21 days after intratesticular injection of 1 or 2 ㎖ of 0.1, 0.5, 1.0 or 5.0% AgNO₃ solutions with or without 88 part of lactic acid. There was found no increase in serum silver content at 170 days of age. The daily gain of body weight of pigs for the period from AgNO₃ treatment to 170 days of age was not significantly (p$gt;0.05) different between 8 control boars (0.61±0.03㎏) and 12 barrows(0.61±0.04㎏). However, the backfat thickness of pigs at 170 days of age was significantly increased in barrows(2.40±0.21㎝), compard with control boars(1.96±0.09㎝).

생쥐 수정란의 유리화 동결보존에 있어서 동결전 처리방법에 관한 연구

공일근,이은봉,강대진,박충생,Gong, Il-Geun,Lee, Eun-Bong,Gang, Dae-Jin,Park, Chung-Saeng 한국동물번식학회 1991 Reproductive & developmental biology Vol.15 No.1

This study was carried out to investigate the effect of equilibration time, precooling and straw loading method on the post-thaw survival rates of mouse embryos cryopreserved by vitrification method. The effect of the vitrification procedure on the damage of the embryos was also examined by the straining of nuclei using Hoechst 33342. The results obtained were summarized as follows; 1. The equilibration in Medium-1 for 10 minutes was considered to be the optimum equilibration time. Embryos equilibrated in Medium-1 for 10 minutes(81.0%) showed significantly(P<0.05) higher survival rates than those equilibrated for 5 minutes(40.0%) or 15 minutes(74.1%). 2. The survival rate of embryos cryopreserved using the double Medium-2 column(81.0%) was significantly(P<0.01) higher than that using the single Medium-2 column, whish was considered to be due to the double Medium-2 column method being more reliable for preventing contamination of diluent solution of 1M sucrose. 3. The survival rate of compacted morula stage embryos cryopreserved with the precooled and non-precooled Medium-2 was not significantly(P<0.05) different. 4. The number of blastomeres of embryos at late blastocyst stage after culture of mouse morulae for 24 to 28hours was significantly(P<0.05) decreased by freezing embryos using vitrification(53.3${\pm}$1.6 vs 41.4${\pm}$1.5), which was considered to be due to the damage of embryos during vitrification and the delay of embryo development by handling in vitro. 5. The vitrification procedure is considered to be a very simple and efficient method for cryopreservation of embryos at early developmental stage.

젖소의 후산정체 예방을 위한 PGF2α 투여효과

정기화,이광원,곽대오,강대진,박충생 ( K . H . Chung,K . W . Lee,D . O . Kwack,D . J . Kang,C . S . Park ) 한국축산학회 1991 한국축산학회지 Vol.33 No.9

To investigate the effect of PGF₂α treatment on prevention of retained placenta and on subsequent reproductive performances of induced-and spontaneous-parturient cows, 151 heads of Holstein cows raised at National Animal Breeding Institute were used. The parturition was induced by injecting 20 ㎎ of dexamethasone into cows at 5 days perior to expected calving date, and to prevent retained placenta a single dose of 10 ㎎ PGF₂α was injected i.m. within 1 hour after induced-or spontaneous-calving. The cows which did not expelled their placenta until 12 hours postparturient were termed as the cow of placenta retention. The calving of cows was induced at 45.5±2.0 hours after injection of dexamethasone. PGF₂α injection after calving to the induced-calving cows resulted in a greater reduction(P$lt;0.01) of incidence of placenta retention (27.3%)than physiologycal saline injected cows (9.09%) In days to the Ist service after calving, there was no significant difference(P$lt;0.05) between spontaneous and PGF₂α treatment after induced-calving, but physiological saline injection after induced-calving cows resulted in significantly(P$lt;0.05) longer days(106.5±27.5 days) than spontaneous calving(66.5±4.1 days). A single dose of 10 ㎎ PGF₂α to 35 spontaneous-calving cows did not significantly(P$lt;0.05) preventive effect on placenta retention (25.7%) compared with physiological saline treatment.

山羊의 自然 및 誘起發情時 發情週期 및 發情持續時間에 관한 硏究

이지삼,송우준,최경문,박충생,Lee, Ji-Sam,Song, U-Jun,Choe, Gyeong-Mun,Park, Chung-Saeng 한국동물번식학회 1991 Reproductive & developmental biology Vol.15 No.1

This study was carried out to investigate the length of the estrous cycle and duration of estrus in Korean native goats. The effects of the type of last estrus : induced or natural, and the length of preceeding estrous cycle on the subsequent cycle and duration of estrus in goats were also examined. From 481 observations, the mean length of estrous cycles was 18.1${\pm}$0.5days. The cycle length was significantly(P<0.05) shorter following induced estrus (15.2${\pm}$0.8 d) than natural estrus(19.0${\pm}$0.6 d). Significantly higher(P<0.05) incidence of short estrous cycle was observed following induced estrus(40%) than natural estrus(27%). The frequency distribution in the estrous cycle was 30%, 3%, 56% and 11% for short(3-11 d), medium(12-16 d), normal(17-24 d) and long(${\geqq}$25 d), respectively. The most frequent type of short estrous cycle was 6 days in length. Mean duration of estrus was 34.0${\pm}$0.5 h with a range of 18 to 84 h. Duration of estrus was not significantly different the preceeding natural (33.8${\pm}$0.6 h) and induced estrus (34.4${\pm}$1.1 h), and was not significantly affected by the last cycle length. These results suggest that the short estrus cycles are more frequent following induced estrus than natural one, and the duration of estrus are affected greatly by the various intrinsic and extrinsic factors.

후산정체 (後産停滯) 가 번식효율과 산유량에 미치는 영향

정기화,조윤연,곽대오,박충생 ( K . H . Chung,Y . Y . Cho,D . O . Kwack,C . S . Park ) 한국축산학회 1991 한국축산학회지 Vol.33 No.7

To investigate the influence of retained placenta on the subsequent reproductive performance and milk yield, total 357 heads of Holstein dairy cows raised at N.A.B.I., Choong Nam province were used. The cows not expelled their placenta until 12 hours postparturient were termed as the cow of placenta retention. The days to first service. days open, services per conception, lactation days, peak yield per day. days to peak yield and 305 days ME milk yield were evaluated to determine the subsequent reproductive performances and milk yield, respectively. The mean incidence of retained placenta(RP) was 25.8% in a herd of 357 cows examined. The cows of placenta retention took significantly(P$lt;0.01) longer than normal cows in the days to first service and the days open, by 97.6±8.4 days and 192.6±15.0 days versus 79.3±2.3 days and 142.9+5.5 days respectively, but services per conception and days open more than 300 were not affected by retained placenta. In milk yield, lactation days, peak yield per day and days to peak yield were not affected by retained placenta, but milk yield per lactation was significantly(P$lt;0.05) decreased in RP cows with 5,684± 151.9㎏ versus 6,035±80.0㎏ for normal cows. From these results, there seemed to be negative relationship between incidence of retained placenta and subsequent reproductive performance and/or milk yied.