• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.3
• /
• pp.308-311
• /
• 2010

An experiment was conducted using indigenous Kivircik ewes to evaluate the effect of intravaginal progestagen sponges, containing 30 mg of fluorogestone acetate (FGA), followed by administration of pregnant mare serum gonadotrophin (PMSG) on inducing synchronized oestrus in the season and fertility. Three times of PMSG administration relative to sponge withdrawal (24 h before (n = 30), at (n = 29) or 24 h after (n= 29)) and two routes of PMSG administration (intramuscular (n = 46) and subcutaneous (n = 42) were compared for estrous response, number of multiple births and fecundity rates. There were no significant differences in terms of estrous response, due to differences in the time and route of PMSG administration. Lambing percentage, proportion of multiple births and fecundity were 75.6, 51.6 and 114.6%, respectively. The administration had a significant effect on lambing (p<0.05), multiple birth and fecundity rates (p<0.01). The subcutaneous administration of PMSG resulted in a significantly higher lambing rate (p<0.05) and fecundity rate (p<0.01), compared to the intramuscular injection of the PMSG.

• Korean Journal of Veterinary Research
• /
• v.34 no.4
• /
• pp.867-872
• /
• 1994

Progesterone catabolizing enzyme, the enzyme $20{\alpha}$-hydroxysteroid dehydrgenase($20{\alpha}$-HSD) is pivotal in the regulation of ovarian function in rodents, which catabolizes progesterone into biologically inactive $20{\alpha}$-hydroxypregn-4-en-3-one($20{\alpha}$-OHP). In this study was carried out the influence of $20{\alpha}$-HSD activity of ovarian function, we investigated changes in ovarian cytosol $20{\alpha}$-HSD activity and serume progesterone concentration during the estrous cycles and pregnancy in rat. During the estrous cycles, the $20{\alpha}$-HSD activities were highest on the progestrous, but serum progesterone concentration was lowest on this phase. During the pregnancy, the $20{\alpha}$-HSD activities were relatively higher early pregnancy(day-1-3 gestation) and late pregnancy(day 21 to parturition), serum progesterone concentration was maintained significantly high to day 19 of gestation. The $20{\alpha}$-HSD activities were lower during the middle pregnancy. From these results, ovarian $20{\alpha}$-HSD activities may possibly act as physiologically very important in the control and maintenance of estrous cycles in rat.

• Advances in Traditional Medicine
• /
• v.4 no.2
• /
• pp.77-81
• /
• 2004

Petroleum ether, benzene and alcohol extracts of seeds of C. juncea administered orally at the dose level of 25mg/100g body weight to adult female mice for 30 days, resulted in irregular estrous cycle with prolonged estrus and metaestrus and reduced diestrus and proestrus during the experimental period. Histological studies of the ovary indicate increases in the number of atretic follicles but decreases in the number of developing follicles, Graafian follicles and corpora lutea. The total cholesterol content of the ovary is increased, whereas ascorbic acid content is decreased. The weight of the uterus and its micrometric measurement in all experimental mice are increased significantly. The alcoholic extracts showed estrogenic activity in immature mice by early opening of the vagina, premature cornification of the vaginal epithilium and increases in uterine weight. However, alcohol extract of seeds of C. juncea was more effective in causing these changes compared to other extracts. After subjecting to preliminary phytochemical screenings alcohol extract showed positive; test for alkaloids, steroids, glycosides, flavones, phenols and tannins.

• Journal of Embryo Transfer
• /
• v.23 no.3
• /
• pp.141-145
• /
• 2008

The objective of this study was to investigate the relationship between behavioral signs and duration of estrous in Hanwoo and Holstein cattle for the prediction of optical insemination. Fifty two of 58 and 71 of 89 in Hanwoo and Holstein cows or heifers showed estrous exhibition within 72 h after 2 days following $PGF_{2}\alpha$ administration, respectively. The number of mounting and standing heat were 54.2 and 57.6, 59.4 and 53.5, 42.0 and 30.8 and 16.2 and 10.7 times in Hanwoo cows, Hanwoo heifers, Holstein cows and Holstein heifers, respectively. Duration of mounting were no significantly difference for Hanwoo cows ($21.2\pm11.3$), Hanwoo heifers ($19.9\pm11.4$), Holstein cows ($8.7\pm4.4$) and Holstein heifers ($16.9\pm8.0$). Duration of standing heat were significantly (p<0.05) shorter for Holstein cows ($5.4\pm3.4$) than for Hanwoo cows ($17.1\pm9.6$), Hanwoo heifers ($16.5\pm6.3$) and Holstein heifers ($15.0\pm7.2$). Time until mounting after injection of $PGF_{2}\alpha$ were significantly (p<0.05) longer for Holstein cows ($56.3\pm11.45$) than for Hanwoo cows ($42.71\pm10.44$), Hanwoo heifers ($36.6\pm8.21$) and Holstein heifers ($40.70\pm6.15$). Time until standing heat after injection of $PGF_{2}\alpha$ were significantly (p<0.05) longer for Holstein cows ($61.6\pm8.92$) than for Hanwoo cows ($46.2\pm11.49$), Hanwoo heifers ($42.7\pm6.06$) and Holstein heifers ($44.1\pm6.72$). In the results of this study, duration of standing heat was the shortest in Holstein cows ($5.4\pm3.4$). The estimation of estrous with Holstein cows has more difficulty because to significantly shorter duration of standing heat than for Hanwoo cows, Hanwoo heifers and Holstein heifers. The standing heat can be a good predictor for time of ovulation but it is concluded that mounting behavior could be the best predictor for time of ovulation.

• Development and Reproduction
• /
• v.8 no.1
• /
• pp.49-55
• /
• 2004

Aquaporins(AQPs) are a family of transmembrane water channel proteins that are widely distributed in various tissues throughout the body and play a major role in Oanscellular and Oansepithelial water movement. Uterine endometrium undergoes recurrent uterine stromal edema in response to hormonal stimuli, however, the mechanism regulating the fluid transport during the estrous cycle has not been fully understood. To investigate the possible role of AQPs in water movement in uterus during the estrous cycle, expression patterns of AQP -1, -3, -4, -5, -8, and -9 UMh in mouse uterus were analyzed by using semiquantitative reverse transcription- polymerase chain reaction(RT-nR). We employed a combination of laser capture microdissection(LCM) and RT-PCR to examine the expression patterns in specific uterine cell types luminal epithelial cells(LE) and stromal cells(S). Our results showed that the level of AQP-4 mRNA was significantly increased while the level of AQP-3 mRNA was significantly decreased during the proestous through the estrus stage. In addition LCM revealed that AQP-4 and -8 mRNAs were highly expressed in LE compared with S. Taken together, these results suggest that AQPs may have an important function in physiological changes of mouse uterus during the estrous cycle.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.7
• /
• pp.1039-1048
• /
• 2007

Two experiments were conducted to determine whether leptin is a metabolic signal for gonadotropin secretion in ewes. In the first experiment, twenty-eight cyclic Chal ewes were assigned randomly to an energy restricted, no leptin group (ERNL) (60% of maintenance; n = 14) and an energy normal, no leptin group (ENNL) (100% of maintenance; n = 14) for 71 days (6 estrous cycles). Estrus was synchronized with seven consecutive injections of $PGF_{2{\alpha}}$ Biweekly, body weight (BW) and body condition score (BCS) were determined and blood samples were collected to measure plasma leptin concentration. Blood samples were also taken to determine plasma progesterone concentration twice weekly. After each PG injection from the second injection to the end of experiment, four ewes were selected and blood samples were collected at 20 minutes and at hourly intervals for 3 h to detect plasma LH and FSH concentration. In the second experiment, after the ceasing of the estrous cycle caused by energy restriction, six acyclic ewes were selected and randomly allotted to two groups (n = 3) and received the following treatment for four days. Ewes in an energy restricted, leptin group (ERL) were fed with a ration which provided 60% of maintenance energy requirements and intravenously injected with $4{\mu}g$ leptin/kg BW daily. Ewes in an energy excess, no leptin group (EENL) were fed with a ration that provided 180% (120%+60%) of maintenance energy requirements and intravenously injected with 1 ml saline daily. In both groups, blood samples were collected at 20 minutes and at hourly intervals for 3 h before feeding on d 0 and d 5, and for 3 h before and after injections as above on d 2 and d 4 to detect plasma LH and FSH concentration. In the first experiment, BW and BCS from the $2^{nd}$ estrous cycle, and leptin from the $3^{rd}$ estrous cycle to the end of the experiment significantly (p<0.05) decreased. In ERNL ewes, mean plasma concentrations of FSH significantly (p<0.01) decreased from the $4^{th}$ estrous cycle to d 71 and LH pulsatile secretion was suppressed on d 71, so that, mean plasma concentrations of LH (p<0.05), LH pulse frequency (p<0.01) and LH pulse amplitude (p<0.05) significantly decreased. In the second experiment, injection of leptin significantly increased mean circulating concentrations of LH (p<0.05), LH pulse frequency (p<0.01), LH pulse amplitude (p<0.05) and mean circulating concentrations of FSH (p<0.01) and leptin (p<0.01). High energy intake significantly (p<0.05) stimulated pulsatile secretion of LH and leptin secretion (p<0.01), but non-significantly increased plasma FSH concentration. The results of this study indicate that leptin is a metabolic signal for the GnRH-LH/FSH axis in feed-restricted fat-tailed ewes.

• Korean Journal of Veterinary Research
• /
• v.35 no.4
• /
• pp.833-841
• /
• 1995

Ultrasonography was used to measure the corpus luteum area for determining the relationships between corpus luteum size and milk progesterone concentration during the estrous cycle in 16 dairy cows. Cows were classified retrospectively into cows that had corpus luteum with(n=P) and without(n=7) cavity. Ultrasound examination and collection of milk samples for progesterone assay were performed with 2 day intervals from Days 0 to 12, and then daily from Day 14 to the day of the next ovulation. The means for corpus luteum area and for milk progesterone concentration during the estrous cycle were not significantly different between cows that had corpus luteum with and without cavity. The correlation coefficients between corpus luteum area and milk progesterone concentration during luteal development (Days 2 to 8) were 0.71(p<0.0001) and 0.74(p<0.0001) for corpus luteum with and without cavity, respectively, during luteal regression(Days -6 to 0 relative to the next ovulation) 0.73(p<0.0001) and 0.76(p<0.0001), respectively. The correlation coefficients combined fur both stages of estrous cycle and both luteal statuses were 0.70(p<0.0001). These results indicate that corpus luteum area is significantly correlated to milk progesterone concentration, and ultrasonographic assessment of the corpus luteum is a reliable method fur estimating peripheral progesterone concentrations during the estrous cycle in cows.

• Development and Reproduction
• /
• v.16 no.2
• /
• pp.113-120
• /
• 2012

We examined the distribution of uterine mast cells in cycling mice of different ages between 7 weeks and 38 weeks by toluidine blue staining. Mast cell density increased gradually depending on the age and culminated at 30 weeks after birth. Of the estrous stages, uteruses at metestrus showed markedly higher density of mast cells than those at the other stages in cycling mice of all ages analysed in this study and the majority of the mast cells were found in myometrium. We also discriminated types of the uterine mast cells in cycling mice at 10 weeks old by Alcian blue-safranin double staining. Mucosal type was most abundant among three types, including connective-tissue types and mixed types, through the entire estrous cycles. The portion of mixed types increased slightly after estrous. The abundance of uterine collagen protein determined by Masson trichrome staining was exactly consistent with the density distribution of the uterine mast cells during estrous cycles. Taken together, these results may imply that uterine mucosal mast cells, together with collagen proteins, are heavily involved in tissue remodeling of cycling mouse uterus.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.8
• /
• pp.1102-1116
• /
• 2012

During embryo implantation in pigs, the uterine endometrium undergoes dramatic morphological and functional changes accompanied with dynamic gene expression. Since the greatest amount of embryonic losses occur during this period, it is essential to understand the expression and function of genes in the uterine endometrium. Although many reports have studied gene expression in the uterine endometrium during the estrous cycle and pregnancy, the pattern of global gene expression in the uterine endometrium in response to the presence of a conceptus (embryo/fetus and associated extraembryonic membranes) has not been completely determined. To better understand the expression of pregnancy-specific genes in the endometrium during the implantation period, we analyzed global gene expression in the endometrium on day (D) 12 and D15 of pregnancy and the estrous cycle using a microarray technique in order to identify differentially expressed endometrial genes between D12 of pregnancy and D12 of the estrous cycle and between D15 of pregnancy and D15 of the estrous cycle. Results showed that the global pattern of gene expression varied with pregnancy status. Among 23,937 genes analyzed, 99 and 213 up-regulated genes and 92 and 231 down-regulated genes were identified as differentially expressed genes (DEGs) in the uterine endometrium on D12 and D15 of pregnancy compared to D12 and D15 of the estrous cycle, respectively. Functional annotation clustering analysis showed that those DEGs included genes involved in immunity, steroidogenesis, cell-to-cell interaction, and tissue remodeling. These findings suggest that the implantation process regulates differential endometrial gene expression to support the establishment of pregnancy in pigs. Further analysis of the genes identified in this study will provide insight into the cellular and molecular bases of the implantation process in pigs.

• Korean Journal of Animal Reproduction
• /
• v.26 no.1
• /
• pp.69-72
• /
• 2002

Two trials were conducted in a commercial dairy on heifer synchronization with PGF$_2$$\alpha$. Animals showing estrous following the first injection were bred and animals not showing estrus were given the second injection 10 days later. In the first trial, the injection routes were rump and rump. In the second trial, the injection routes were rump and shoulder. Estrous detection were performed from 24 h after injection. Animals were bred by the same technician. In the first trial, the response rate for the first injection was 51.4% and the subsequent pregnancy rate of these animals was 60.0%. The response rate in the second injection was 57.1% and the pregnancy rate was 50.0%. In the second trial, the response rate in the first injection on the rump was 48.7% and the subsequent pregnancy rate was 70.6%. The second injection was given on the shoulder and the response rate was 60.0% and the subsequent pregnancy rate was 25.0%. The data suggest that the route of PGF$_2$$\alpha$ administration was critical to achieve success in estrous synchronization and pregnancy rates.