본 연구에서는 한우 암소와 씨수소의 육종가를 기반으로 연도별 유전적 개량량을 추정하여 현재 한우 축군의 개량 정도를 파악하여 향후 한우 개량 방향을 위한 기초자료로 활용하고자 본 연구를 시행하였다. 본 연구를 위하여 한우농가 4,040호에서 축산물품질평가원에 도축된 970,567두의 도축자료를 이용하여 10번 반복되어 추출된 표본 자료와 한우농가에서 2009년부터 2019년까지 사육되고 도축된 개체 중에서 한국종축개량협회에 혈통등록 되어 있는 거세우를 선별하여 결측치 및 이상치를 제거하고 도축월령이 27~32개월 이외의 기록은 분석에서 제외한 후, 1,391,141두의 도체 자료를 분석에 이용하였다. 이용된 형질은 도체중(Carcass Weight, CW), 등심단면적(Eye Muscle Area, EMA), 등지방두께(Backfat Thickness, BF) 및 근내지방도(Marbling Score, MS)의 4개 형질을 고려하였다. Random Sampling 10 반복되어 추출된 Data 1의 도체중, 등심단면적, 등지방두께 및 근내지방도의 개량추세에 대한 회귀계수는 매년 평균 0.44㎏, 0.197㎠, -0.051㎜ 및 0.034점으로 나타났으며, 도축성적을 보유한 전체 개체의 자료로 구성된 Data 2에서는 각각 0.35㎏, 0.22㎠, 0.06㎜ 및 0.04점의 개량추세를 보였다. Data 2에서 씨수소의 개량추세는 1.54㎏, 0.343㎠, -0.045㎜ 및 0.050점의 추세를 보였으며 암소와 씨수소 간에는 1.19㎏, 0.119㎠, -0.014㎜ 및 0.010점의 차이를 보였다. 유전적 개량량을 확인하기 위하여 육종가의 표준편차를 이용하였으며, 암소의 선발강도는 본 연구에서 보고한 암소의 후대 거세우 기록 빈도 및 비율을 통해 계산하였다. 한우 암소의 선발 시기를 3산차 이전을 기준으로 하는 것과 4산차 이후를 기준으로 하는 것으로 나눠서 선발강도를 적용하였다. 그 결과, 암소의 선발 시기를 3산차 이전으로 했을 때 세대당 유전적 개량량은 도체중, 등심단면적, 등지방두께 및 근내지방도에서 각각 5.04㎏, 1.31㎠, 0.71㎜ 및 0.32점으로 나타났다. 이러한 결과를 바탕으로 현재 한우 암소집단에서 정확한 육종가를 추정하고, 유전적 개량량을 높이기 위해서는 후대의 기록을 높이기 위한 육종 계획이 필요할 것으로 판단된다.

1. 농촌진흥청 연구과제를 통해 국내 젖소 정액의 수출여건 조사를 제공하고자 우간다 낙농 유전자원 및 인공수정 현황과 수출사례를 통해 국내 젖소 정액의 수출여건 대응 향상 방안을 제시하였다. 2. 우간다의 농업분야는 가용노동력의 70%, GDP의 약 24%를 차지하고 있을 만큼 GDP와 고용측면에 있어 경제의 핵심부문이며 그 중 낙농산업은 축산분야 중 높은 성장률을 보이고 있다. 그러나 동물유전자원과 관련된 전반적인 업무를 총괄하는 국립동물유전자원센터는 수입 유전자원을 정액 형태로 농가에 보급하는 수준에 그치고 있다. 3. 한국은 열악한 기후조건에도 불구하고 세계 3위권의 마리당 일일 우유 생산량을 기록하여 낙농 유전자원의 우수성을 증명하고 있다. 인공수정을 통한 품종 개량 시 유생산 우수 젖소를 효율적으로 확보할 수 있으며, 우간다 농민은 한국 젖소 정액을 활용하여 평균 유량이 어미 소의 2배인 딸소를 생 산하였다. 4. 우간다에 한국 젖소정액 수출은 양국 정부와 여러 관련 기관들의 협조 하에 이루어졌으며 그 과정에서 발생하였던 내용을 토대로 한국 젖소정액의 수출 진입장벽 해소를 위한 방안을 제시하였다.

Antioxidants have been added to cryoprotectant or in vitro culture medium for sperm to reduce the detrimental damage, such as reactive oxygen species. However, curcumin, an antioxidant, shows dual effect on the viability and progressive motility of bovine sperm exposed to hydrogen peroxide. Low concentration of curcumin increases sperm viability and progressive motility, whereas high concentration of curcumin reduces them. This study was performed to identify whether TREK-1 channel is related to low sperm viability and motility induced by high concentration of curcumin. Curcumin reduced TREK-1 channel activity in a dose-dependent manner. TREK-1 channel was expressed in sperm obtained from Korean native bull. Treatment with TREK-1 channel blockers, such as curcumin, fluoxetine, GdCl3, and spadin, significantly reduced sperm viability and motility (p < 0.05). However, TREK-1 channel activators showed different effect; linoleic acid showed an increase in sperm viability and motility, and wogonin did not affect them. These results show that TREK-1 channel is involved in the regulation of sperm viability and motility. In particular, high concentration of curcumin might reduce sperm viability and progressive motility of Korean native bull through blockage of TREK-1 channel.

Sperm recovery from epididymis in animals considered as important tools to preserve high-value or endangered species. However, there are no appropriate castrating indicators of timing for recovery of sperm which can be available to artificial reproduction technologies such as artificial insemination (AI) and in vitro fertilization (IVF), particularly in young Hanwoo bull. Therefore, this study aimed to investigate semen volume, morphology and motility of sperm in epididymis of young Hanwoo bulls at 8, 13, 14, and 15 months of age. About 2 cm of the epididymal tail only was cut and minced using blades. Minced epididymal tail tissues were mixed with semen extender (OptixCell, France, IMV technologies) and sperm were recovered with a cell strainer (100 μm nylon mesh). The number of sperm at 8 months of age was lower than that at 13, 14, 15 months of age in bulls after collection (33.6±27.2 vs. 352.4±39.2, 320.4±113.6 and 422.8±252.4×107cells respectively; P<0.05). After the frozen-thawed sperm the the percentage of abnormal head, tail and dead damaged acrosome did not differ between the ages 13, 14 and 15 months of age in bulls (P>0.05), however, the dead sperm with intact acrosome (DIA), the numbers showed that more than 15 months in 8, 13, 14 months (8.7±4.1 vs. 47.3±12.2, 34.8±14.0, 28.8±8.5, P<0.05). In addition, frozen-thawed sperm at 8 months of age showed low total motile sperm compared to those at 13, 14 and 15 months of age (26.4±8.2 vs. 45.7±29.5, 62.3±41.0, 70.4±15.9%, respectively; P<0.05). In conclusion, sperm derived from epididymal tail at 8 months of age in Hanwoo bulls showed high abnormal morphology and poor motility, which is not adequate for artificial insemination(AI) and in vitro fertilization(IVF). On the other hand, sperm derived from epididymal tail at 13, 14, 15 months of age in bull showed high normal morphology and motility, which may be available for AI and IVF. Epididymal sperm collected from bulls over 13 months is needed for further study whether to use the actual in vitro fertilization.

The recovery of epididymal sperm in animals is considered as one of the important tools to preserve high value or endangered species. However, there are no appropriate castrating indicators such as months of age in bull, sperm morphology, and motility, particularly in young Korean native bull (Hanwoo). Therefore, this study aimed to investigate sperm number, morphology, and motility of sperm in the epididymis tail of young Hanwoo bulls at 8 and 15 months of age. After castration, epididymal tails were collected and minced with blades to recover sperm. In experiments 1 and 2, sperm number, morphology, and motility were examined. Total number of sperm and percentage of normal sperm from bulls at 8 months of age was lower than that of bulls at 15 months of age after collection (P<0.05). Percentage of abnormal head, tail, proximal cytoplasmic droplet, dead and damaged acrosome of sperm from bulls at 8 months of age were higher than those of bulls at 15 months of age (P<0.05). In experiment 3, sperm motility from bulls at 8 and 15 months of age were examined before freezing and after thawing. Frozen-thawed sperm at 8 months of age showed low total motility and motile sperm with ≥ 25 μm/sec compared to those at 15 months of age and commercially-used sperm (P<0.05). In conclusion, sperm derived from the epididymal tail of bulls at 8 months of age showed high abnormal morphology and poor motility, which are not adequate for AI and IVF. On the other hand, sperm derived from the epididymal tail of bulls at 15 months of age showed high normal morphology and motility.

The decreased fertility is frequently thought to be problem of cattle production. However, studies figure out that number of these problems is related to bull factors especially in artificial insemination setting. Therefore, this study was designed to investigate the fertility status of bull by their estimated relative conception rate of cows that were inseminated by frozen semen from Korean proven bulls. Here we use the non-return rate (NRR) to access the bull fertility whereas, the NRR was define as the proportion of bulls that semen were used to inseminate cows and the number of cows that did not return for another service within 60 days. The data from 54,388 artificial inseminations (AI) were analyzed from 88 KPN semen. The NRRs of highest and lowest fertile bull were 83.81 and 51.33%, respectively. And mean NRR was 68.27%. In comparison to previously reported study, our data shows 17.38% higher NRR and the absolute value of difference in 50%>NRR and 50%<NRR group was 22.17 and 10.51, respectively (p< 0.001). In conclusion, the decreased fertility might consider as key aspect in achieving considerable conception of cows in existing integrated farming system at Korea.

This study was designed to determine whether low-density lipoporoteins (LDL) extracted from egg yolk in extender improve the function of Korean Jeju Black Bull semen. The semen was cryopreserved with 5% ethylene glycol (EG) or 7% glycerol (G) extenders containing 10% egg yolk (EY), 4% LDL and 5% EY or 8% LDL. Frozen-thawed sperm were evaluated sperm motility, viability, membrane integrity and acrosome integrity. Post-thawed sperm motility has been significantly higher (p<0.05) in 4% LDL + 5% EY (; EG and ; 7% G) than 8% LDL (; EG and ;G). Treatment of 4% LDL + 5% EY-EG () has been significantly improved sperm viability compared to other treatments except 10% EY - EG. Moreover, in membrane integrity, swollen sperm ratio has been only significantly increased (p<0.05) in 4% LDL + 5% EY - EG () among all treatments. In assess to detect acrosome integrity, especially, AR pattern ratio has been significantly decreased (p<0.05) in 4% LDL + 5% EY - EG among all treatments. In sperm viability as time passes, between 4% LDL + 5% EY and 10% EY, there was no significant difference, but 8% LDL was significantly decreased sperm viability in EG (1 and 2 hrs) and G (30 min, 1, 2, 5 and 12 hrs) extender. However, there were no significant differences among all treatments except 8% LDL-G in sperm membrane integrity. 8% LDL-G has been significantly decreased swollen sperm ratio at 5 hrs after thawed. It is concluded from these results that 4% LDL + 5% EY to the freezing extender showed more positive effect on the frozen-thawed spermatozoa in Korean Jeju Black bull.

This study was designed to determine whether low-density lipoproteins (LDL) from egg yolk and taurine, hypotaurine and trehalose as antioxidant in extender improve the freezability and fertility of Korean Jeju Black Bull semen. The semen was cryopreserved with tris egg yolk extenders containing 7% glycerol and treated 4% LDL, 20 mM taurine, hypotaurine and trehalose. Frozen-thawed sperm were evaluated motility, viability, membrane, and acrosome integrity and sperm penetration ability. The results were compared to semen cryopreserved in tris egg yolk extender only as control. Frozen-thawed semen evaluation cleary indicated that the addition of LDL and LDL-antioxidants (taurine, hypotaurine and trehalose) combination were significantly improved (p<0.05) the viability (%; with staining test using eosin-Y) compared to control spermatozoa. Also, in membrane integrity (%; with supravital hypo-osmotic swelling test), not only LDL-antioxiants combination but also LDL were significantly increased (p<0.05) the swelled sperm using HOST compared to control. Sperm acrosome integrity state was classified by CTC (chlortetracycline) staining test. F pattern was significantly increased in LDL-antioxidant combination than control (p<0.05) and B pattern was not significantly differences among all treatments and control. However, AR pattern was significantly decreased in LDL-antioxidants combination than control (p<0.05). Pronucleus formation and sperm penetration index (SFI) were significantly increased in LDL and LDL-antioxidants combination than control (p<0.05). Especially, LDL-taurine significantly improved pronucleus fomation and SFI than LDL (p<0.05). It was concluded that LDL and LDL-antioxidants in extender improved the freezability and fertility of Korean Jeju Black bull spermatozoa.

The purpose of this study was to examine the effect of growing stages of the Korean Native Striped Bull (KNSB) on the freezability and fertility of frozen-thawed semen. First, we investigated the total motility (TM) and progressive motility (PM) according to the diluent used for semen freezing. Second, we examined the effect of the age of KNSB on semen volume, TM and PM of fresh and frozen-thawed semen. Third, we examined the effect of frozen semen from the different age of KNSB on the fertilization rate, and the artificial insemination pregnancy rate. The diluents used in this experiment were Triladyl and Tris-egg yolk extender (EYE). Semen was collected from 5 KNSB in the growing stage (15 months) and 5 adult KNSB (36 months). When Triladyl or Tris-EYE extender was used for semen freezing, there was no difference of the mean TM and the mean PM. However, the mean TM was significantly higher in Bull No. 1885 than Bull No. 4283 ( <0.05). The mean volume of semen collected from the 15-month-old bulls (2.3 ml) was significantly lower ( <0.05) than that from the 36-month-old bulls (5.0 ml). The mean semen concentration was similar for the 15-month-old ( spermatozoa/ml) and 36-month-old ( spermatozoa/ml) bulls. For the 15-month-old and 36-month-old bulls, the mean TM of fresh semen were 93.7% and 88.3%, respectively, and the mean PM were 97.0% and 88.3%, respectively; the 15-month-old bulls showed a particularly high PM ( <0.05). For the 15-month-old and 36-month-old bulls, the mean TM (56.0% and 58.0%, respectively) and the mean PM (64.0% and 70.7%, respectively) of frozen-thawed semen did not differ. The development rates of embryos after fertilization and the pregnancy rate after artificial insemination using frozen-thawed semen did not differ according to the bull's age. In summary, semen volume differed according to the bull's age, but semen concentration and survival rate, the fertilization rate, and the pregnancy rate did not differ according to the stripe bull's age. Accordingly, semen from bulls in the growing stage can be collected and frozen for the preservation and multiplication of rare livestock.

The objective of this study was to examine effect of ethylene glycol for semen cryopreservation in Korean Jeju Black Bull. The semen was cryopreserved with extenders containing cryoprotectants (7% glycerol and 3%, 5%, 7% ethylene glycol) and packed to 0.5 ml straws. The semen straws were located above 3 cm of liquid nitrogen for 5 min, 5 cm for 10 min and 8 cm for 10 min. And then frozen straw was plunged into LN2. Post-thawed sperm motility, viability and membrane integrity were significantly higher in 5% ethylene glycol (72.5±5.00%, 54.88±0.66% and 46.00±2.40%; p<0.05). Motility and viability were similar between 7% glycerol and 5% ethylene glycol. However, the membrane integrity was significantly higher in 5% ethylene glycol (34.69±4.64% vs 46.00±2.40%; p<0.05). The viability and membrane integrity were significantly higher in 5 cm for 10 min and 8 cm for 10 min than 3 cm for 5 min (viability: 55.81±2.94, 55.19±3.34 vs 47.94±3.48%; p<0.05 and membrane integrity: 44.94±3.51, 46.06±2.25 vs 40.38±1.03%; p<0.05). The percentage of capacitated sperm assessed by CTC staining, percentage of F pattern was higher in 7% glycerol, 5% and 7% ethylene glycol, and AR pattern was significantly higher in 3% ethylene glycol. F pattern was significantly increased in 5 cm for 10 min and 8 cm for 10 min (p<0.05), but AR pattern was significantly increased in 3 cm for 5 min (p<0.05).

This study was carried out to establish most suitable freezing condition, to evaluate the different glycerol concentration of freezing and thawing rates on motility, viability, membrane integrity and acrosome intecrity of frozen Korean Jeju Black Bull spermatozoa, Semen was collected from a Korean Jeju Black Bull using an artificial vagina and transported to the laboratory. The semen was extended gradually 1:5 then cooled slowly for 2 hrs to 4. The semen was diluted 1:1 with cryoprotectant extenders (3%, 5% and 7% glycerol) and equilibrated for 2 hrs at cold chamber and packed to 0.5 ml straws. The semen straws were located above 3 cm of liquid nitrogen for 5 minutes, above 5 cm for 10 min and above 8 cm for 10 min. And then the frozen straw was plunged into LN. The presented straws were examined the viability and motility after thawed at 37 water bath. The viability and membrane integrity immediately post-thawing were significantly higher in samples frozen in 7% glycerol than 3% and 5% glycerol (p<0.05). After CTC staining to assess acrosome integrity, F pattern was significantly increased, but B pattern was significantly decreased in 7% glycerol (p<0.05). Freezing distance of 5 cm from liquid nitrogen and pre-cooling for 10 min yield better survival and membrane integrity, but not significant difference. However, AR pattern according to CTC staining was significantly decreased in 3 cm for 5 min.

희소 한우인 칡소의 정액 동결을 위해서 레시딘을 기본 희석제로 하는 AndroMed와 Tris-egg yolk extender를 사용하여 정자의 생존율과 활력 조사를 위해서 본 연구를 수행하였다. AndroMed 희석제를 사용하였을 때 생존율과 활력은 와 의 결과를 보였다. 그리고 Tris-egg yolk extender의 경우는 각각 와 결과를 보여 생존율에서는 Tris-egg yolk 희석제가 AndroMed 희석제를 사용하였을 때보다 유의적으로(p

This study was conducted to examine the effect of fermented alcoholic feedstuff (FAF), sustained-release recombinant bovine somatotropin(rBST) on growth performance and body size of Korean native cattle, Hanwoo. The experiment was carried at the Livestock Breeding Station in Kangwon-do with fourteen bulls of two groups, control and treatment. Seven bulls per each group were allocateed. In control group, bulls were treated with total mixed ration(TMR) for the whole experimental periods. In treatment group, bulls were treated with TMR+FAF+rBST for the fattening period and TMR+FAF for the finishing period, respectively. The results are summarized as follows ; Average daily gains(ADG) of control and treatment groups were 0.86 and 1.11kg during the fattening period. ADG of treatment group were 29.1% higher than that of control group. For the whole experimental period, the fattening period and finishing period, ADG in control and treatment groups were 0.69 and 0.79kg, respectively, which shows 14.5% improvement of ADG in treatment group. Dry matter intake(DMI) was higher in treatment group than in control group during the finishing, fattening or whole experimental period. Feed conversion efficiencies in fattening period were 8.65 for control group and 6.93 for treatment group which shows improving 19.9% of feed conversion efficiency for treatment group, while 12.38 for control group and 14.48 for treatment group in finishing period. There were no significant differences between control and treatment group in feed conversion efficiency for the whole experimental period. Overall results indicate that the favorable feeding system to produce growth performance is TMR+FAF+rBST feeding during the fattening period and TMR+FAF feeding in treatment during the finishing period.

본 연구는 숫소 개체별, 정자의 형태, 정자의 전처리 및 난자의 투명대부착과 미부착별로 현미조작에 의해 난자의 세포질내 단일정자를 주입했을 때 웅성전핵 형성율과 체외발생율을 조사하였다. 1. 숫소 개체별 정자를 이용하여 ICSI를 하였을 때 웅성전핵 형성율은 각각 73.9∼87.0%였고 체외발생율은 33.3∼60.9%를 나타냈다. 2. 신선 및 동결정자와 미부절단 정자와 두부, 미부손상 정자를 이용하여 ICSI를 하였을 때 웅성전핵 형성율은 각각 82.

본 연구는 종모우의 선발방법으로 난포란을 이용하여 실험실내 정자의 수정능력을 직접 검정하여 평가코자 시도되었다. 즉 본 실험은 후대검정중에 있는 한우 후보종모우 15두의 동결융해정자의 수정능력을 평가하기 위하여 정액을 고장액(HIS)에 처리한 후 DM에서 6시간 그리고 소 난포액이 20% 첨가된 DM에서 4시간 전배양하여 수정능을 획득시켜 정자의 활력과 첨체 반응율을 조사하였고 전배양된 정자의 체내(토끼 난관) 또는 체외수정능력을 조사하기 위하여 FCS