This study was carried out to develop the useful inducing method of estrus for Korean native cows. Under the condition of estrus induction by administering for the cows in which corpus luteum (CL) in ovaries was detected by ultrasonography, ovarian responses and the changes of progesterone () concentration against compared with conception rate were observed in cows and heifers. In inducing estrus administering . to the cows which has corpus luteum in ovaries, ovarian reponses, the changes of progesterone concentration, and conception rate were identified and compared. The results attained from the studies were as follows. Significant decreases of CL in size over time after administration were detected in both cow and heifer groups (p<0.001), but not different between groups in the CL regression rate (p>0.05). In addition, the percentage changes relative to the plasma concentration on day 1 after treatment were decreased to below 1ng/ml. The growth rate of follicle was observed as 31% on day 1 and 42% on day 2 in cows, and 34% on day 1 and 97% on day 2 in heifers, resulting that growth of heifers are faster than that of cows (p<0.05). The conception rate after treatment were 60.5% and 64.2% in cows and heifers, respectively. It also indicated that the conception rate after estrus observation with injection was as high as 66.6% while that with timed-artificial insemination (TAI) regardless of the estrus observation was 56%, which means the pregnancy rate of artificial insemination after estrus observation was higher than that of TAI (p<0.05). In the result of all above, there were significant decreases in CL size and the plasma concentration by days but rapid growth in follicles, which has no differences in cows and heifers. The conception rate was commonly high after estrus observation and more than 50% under TAI.

The purpose of this study was to determine the relationship between conception rate and other parameters (body condition score; BCS, progesterone concentrations and follicle size) before estrus induction with CIDR(intravaginal progesterone-releasing controlled internal drug release). The conception rate in cows with < 2.75, 2.75 to 3.25, and 3.25 <, BCS regardless of AI (artificial insemination) time was 46.6%, 63.3%, and 46.6% at CIDR insertion, respectively. The conception rate regardless of BCS was 54.9% in cows inseminated based on detected estrus, and 48.7% in cows inseminated at 72 to 80 hours (timed artificial insemination, TAI) after removal of CIDR. The conception rate regardless of AI time was 40.0% in cows with low progesterone concentrations (less than 1.0 ng/ml), and 56.6% in cows with high progesterone concentrations (more than 1.0 ng/ml) at CIDR injection. The conception rate regardless of progesterone concentrations was 53.8% in cows inseminated based on detected estrus, and 38.0% in cows of TAI after removal of CIDR. The conception rate regardless of AI time was 43.3% in cows with small follicle (less than 5 mm), 53.3% in cows between 5 mm to 10 mm of follicle, and 63.3% in cows with large folliclc (more than 10 mm) at CIDR injection, respectively. The conception rate regardless of follicle size was 58.4% in cows inseminated based on detected estrus, and 45.9% in cows of TAI after removal of CIDR. These results indicated that if the cows with BCS 2.75 to 3.25, active corpus luteum, and/or large dominant follicle (more than 10 mm) are used for estrus induction, the conception rate will be greater.

The purpose of this study was to determine the relationship between conception rate and other parameters (body condition score; BCS, progesterone concentrations and follicle size) before estrus induction with . The conception rate in cows with (2.75, 2.75 to 3.25 and 3.25), BCS regardless of AI (artificial insemination) time was 47.5, 67.5% and 48.5% at injection, respectively. The conception rate regardless of BCS was 59.0% in cows inseminated based on detected estrus, and 46.2% in cows inseminated at 72 to 80 hours (timed artificial insemination, TAI) after injection. The conception rate regardless of AI time was 43.0% in cows with low progesterone concentrations (less than 1.0 ng/ml), and 67.5% in cows with high progesterone concentrations (more than 1.0 ng/ml) at injection. The conception rate regardless of progesterone concentrations was 59.9% in cows inseminated based on detected estrus, and 48.1% in cows of TAI after injection. The conception rate regardless of AI time was 36.0% in cows with small dominant follicles (less than 5 mm), 56.0% in cows between 5 mm to 10 mm of follicle size, and 65.5% in cows with large dominant follicles (more than 10 mm) at injection, respectively. The conception rate regardless of follicle size was 57.3% in cows inseminated based on detected estrus, and 47.6% in cows of TAI after injection. These results indicated that if the cows with BCS 2.75 to 3.25, active corpus luteum, and/or large dominant follicle (more than 10 mm) are used for estrus induction, the conception rate will be greater.

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, , Vetrepharm); FSH (H), FSH (3.0 mg/kg, twice a day); GnRH+FSH, GnRH (5 ug/kg, once first day, , Dongbang)+FSH (3 mg/kg, SID); PMSG, PMSG (50 IU/kg, every third day , 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, , Novartis). The bitches were evaluated clinical sign, cytological exam and 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 Premate. Proestrus initiated by the after induction in most case. In conclusion, bromocriptine is an effective drug for estrus induction in bitches and assay of progesterone concentration by Premate with examination of vaginal smear that should be useful to detection of estrus induction of estrus induced bitches.

To search a new pig pheromonal odorant, the N1-allyl-N2-(tetrahydrofuran-2-ylmethyl)oxalamide molecule predicted by ligand based approach and molecular docking method was synthesized by nucleophilic addition-elimination reaction (AdNU-E) between N-allyloxalamic acid ethylester and tetrahydrofurylmethylamine. According to the evaluation results for efficiency of pig estrus control, the synthesized pig pheromonal N1-allyl-N2-(tetrahydrofuran-2- ylmethyl)oxalamide molecule advanced the estrus by 11.3 days (p<0.05) compared with the non-pheromone group. And from these results, it is predicted that the synthesized pig pheromonal compound will be able to increase the reproduction efficiency of pig.

무발정 증상을 보이는 젖소 65두를 대상으로 몇 가지 호르몬 처리기법을 사용하여 소의 번식효율 향상시키고자 본 실험을 수행하였다. Group 1. Ovsynch program (GnRH-PGF a /PGF a/GnRH), Group 2. Two plus Two program (GnRH-PGF a /PGF a/GnRH), Group 3. progesterone implant (CIDR)-GnRH/PGF a/PGF a/GnRH과 Group 4. (Folli

본 실험은 개의 인공수정에 사용할 신선정액, 그리고 동결정액을 이용한 자연교미와 발정유도된 실험견에 인공수정시 임신율과 산자수를 검증하여 그 효율성을 조사하였다. 1. 개의 인공수정시에 자연발정, clomifene, bromocriptine 단독 투여 그리고 GnRH + bromocriptine/GnRH 혼합 투여에 따른 발정유도방법은 임신율과 산자수에 영향을 미치지 않는 것으로 나타났으며, 신선정액을 이용한 인공 수정방법은 자연교미방법과 유사한 임신율