• Animal Bioscience
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• 제37권1호
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• pp.95-104
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• 2024

Objective: In the present study, we aimed to investigate the effects of enzymolysis fermentation of Chinese herbal medicines (CHMs) on egg production performance, egg quality, lipid metabolism, serum reproductive hormone levels, and the mRNA expression of the ovarian hormone receptor of laying hens in the late-laying stage. Methods: A total of 360 Hy-Line Brown laying hens (age, 390 days) were randomly categorized into four groups. Hens in the control (C) group were fed a basic diet devoid of CHMs, the crushed CHM (CT), fermented CHM (FC), and enzymatically fermented CHM (EFT) groups received diets containing 2% crushed CHM, 2% fermented CHM, and 2% enzymatically fermented CHM, respectively. Results: Compared with crushed CHM, the acid detergent fiber, total flavonoids, and total saponins contents of fermented CHM showed improvement (p<0.05); furthermore, the neutral and acid detergent fiber, total flavonoids, and total saponins contents of enzymatically fermented CHM improved (p<0.05). At 5 to 8 weeks, hens in the FC and EFT groups showed increased laying rates, haugh unit, albumin height, yolk color, shell thickness, and shell strength compared with those in the C group (p<0.05). Compared with the FC group, the laying rate, albumin height, and Shell thickness in the EFT group was increased (p<0.05). Compared with the C, CT, and FC groups, the EFT group showed reduced serum total cholesterol and increased serum luteinizing hormone levels and mRNA expressions of follicle stimulating hormone receptor and luteinizing hormone receptor (p<0.05). Conclusion: These results indicated that the ETF group improved the laying rate and egg quality and regulated the lipid metabolism in aged hens. The mechanism underlying this effect was likely related to cell wall degradation of CHM and increased serum levels of luteinizing hormone and mRNA expression of the ovarian hormone receptor.

• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.756-764
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• 2009

Provision of an optimal environment for the calf is critical to establishing the patterns of growth and development essential to allow the heifer to express its genetic potential for milk output and reproductive capacity during its productive life. Maternal nutrition during gestation is now recognised as a key to genetic programming in utero and this influence is extended through the complexity of hormones, growth factors and immunostimulants incorporated into colostrum and milk consumed by the neonatal calf. This natural process is most often disrupted as calves are weaned abruptly to maximise milk output for commercial exploitation. The key then is to accelerate the rate of maturation of the ruminal epithelium through the provision of concentrate starter rations and high quality forage, which promote VFA production. Management systems to promote these processes in Holstein Friesian cattle are well developed, however, little is known of these processes with buffalo and Bos indicus dairy cattle such as the Sahiwal. The development of methods to program the neonate to grow faster to puberty in these species will be important to improving their productivity for the dairy industries in tropical and sub-tropical environments in the future.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.176-179
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• 2003

Insulin-like growth factor-I (IGF-I) is a polypeptide that has the function of regulating the expression of steroid hormones through endocrine, paracrine, and autocrine actions in reproductive organs. Moreover, IGF-I is involved in ovulation, implantation, maintenance of pregnancy, and development of fetuses in animals. Therefore, this study was conducted to investigate the effects of serum IGF-I concentration on progesterone ($P_4$) concentration and pregnancy rates in Korean native cattle (Hanwoo). Blood was collected at estrus (Day 0) and Day 11. Artificial insemination was performed at Day 0. Serum IGF-I and $P_4$ concentrations were measured by radioimmunoassay (RIA). Overall, $P_4$ concentration was higher at Day 11 than Day 0, whereas the pattern of IGF-I concentration was reversed. When animals were divided into two groups depending on the pregnancy status, $P_4$ concentrations of the pregnant group was significantly higher than that of the non-pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05). But, lower IGF-I concentrations were detected in the pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05) compared to the non-pregnant group. In conclusion, these results indicated that serum IGF-I is inversely associated with $P_4$ concentration during early pregnancy in Hanwoo.

• 한국가축번식학회지
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• 제14권1호
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• pp.73-83
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• 1990

These studies were carried out to find the proper conditions for in vitro maturation and fertilization of bovine follicular oocytes and culture methods capable of further developing early embryos. For these objectives, the cleavage rate of oocytes matured and fertilized in vitro was investigated under medium supplemented with hormones and estrous cow serum and season of oocytes collection as well as different cumulus cell stage before insemination. Finally, 2~8 cell embryos were cultured in in vitro and in vitro culture system to investigate developmental capacity into morula. 1. Cleavage rate of oocytes matured in vitro was 27%(20/73) for A(LH＋FSH＋estradil-17$\beta$＋10% FBS), 38%(27/71) for B(LH＋10% ECS) and 27%(15/56) for C(10% ECS), respectively. Supplement B showed more higher rate and 4~8 cell embryos were also obtained much more in this group(67%, 18/27). In vitro maturation rate of follicular oocytes cultured in TCM 199 supplemented withLH and 10% ECS was 88%(75/85). 2. Cleavage rate(15%, 10/65) of oocytes collected in summer was significantly lower than in fall(47%, 42/89). 3. Cleavage rate(15%, 10/65) of oocytes collected in summer was significantly lower than in fall(47%, 42/89). 3. Cleavage rate(15%, 10/65) of oocytes with partially removed cumulus cell before insemination was more higher than that(44%, 27/62) of oocytes with intact cumulus cell. 4. The frequency of development from early cleaved embryos into morula was 6%(4/65), 12%(4/33) for co-culture of cumulus cell monolayer and bovine oviduct epithelial cell monolayer, respectively and 25%(6/25) in ligated rabbit oviduct.

• 한국발생생물학회지:발생과생식
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• 제1권2호
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• pp.189-202
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• 1997

The hypothalamic peptide GnRH plays a central role in the regulation of the mammalian reproductive axis. Recent studies suggested that GnRH stimulates or inhibits the ovarian steroidogenesis and gametogenesis directly. Our previous report indicated that GnRH gene is expressed in adult rat ovary as well as in hypothalamus and that the expressed GnRH may induce the follicular atresia and apoptosis of ovarian granulosa cells in rat. Therfore, we studied whether GnRH gene is expressed in the mouse fetal ovary, when the germ cells are degenerating by apoptosis during gonad diffeerentiation. Mouse fetal gonads were obtained on the 12, 15,18 and 20th day of gestation from the mother mice superovulated (10 IU PMSG and 10 IU hCG) and mated. The morphological changes of fetal ovaries were examined histochemically by hematoxylin-eosin staining. The fetal sex was confirmed by PCR methods for sexing. RT-PCR methods were used to examine the expression of GnRH gene and the sex steroid hormones were determined by conventional radioimmunoassays. The levels of estradiol (E) and progesterone (P) were increaseduntil 18th day of gestation and then E was decreased just before parturition. The morphological changes of fetal gonadal tissue sections showed the ovarian development and coincided with the result of PCR analysis for sexing using ovary- or testis- specific oligonucleotide primers. Immunoreactive GnRH in placenta was decreased gradually until the end of gestation but fetal brain and ovarian GnRH were increased. The level of GnRH gene expression was increased during fetal ovarian development from 12 till 18th day and decreased suddenly on 20th day just before birth. From these results, it is suggested that ovarian GnRh may play a regulatory role on the germ cell differentiation of fetal ovary.

• 한국발생생물학회지:발생과생식
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• 제19권1호
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• pp.43-51
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• 2015

Connexin (Cx) is a complex which allows direct communication between neighboring cells via exchange of signaling molecules and eventually leads to functional harmony of cells in a tissue. The initial segment (IS) is an excurrent duct of male reproductive tract and expression of numerous genes in the IS are controlled by androgens and estrogens. The effects of these steroid hormones on gene expression in the IS during postnatal development have not extensively examined. The present research investigated expressional modulation of Cx isoforms in the IS by exogenous exposure to estrogen agonist, estradiol benzoate (EB), or androgen antagonist, flutamide (Flu), at weaning age. Two different doses of EB or Flu were subcutaneously administrated in 21-day old of male rats, and expressional changes of Cx isoforms in the adult IS were analyzed by quantitative real-time PCR. Treatment of a low-dose EB ($0.015{\mu}g/kg$ body weight) resulted in an increased expression of Cx31 gene and a decreased expression of Cx37 gene. A high-dose EB ($1.5{\mu}g/kg$ body weight) treatment caused an increase of Cx31 gene expression. Increased levels of Cx30.3 and Cx40 transcripts were observed with a low-dose Flu ($500{\mu}g/kg$ body weight) treatment. Treatment of high-dose Flu (50 mg/kg body weight) led to expressional increases of Cx30.3, 40, and 43 genes. Our previous and present findings suggest differential responsiveness on gene expression of Cx isoforms in the IS by androgens and estrogens at different postnatal ages.

• 한국가축번식학회지
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• 제7권2호
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• pp.72-85
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• 1983

This presentation firstly is discussed the characteristics of estrus, the time of first postpartum estrus, and the relative accurate of various estrus detection aids and secondly discussed the abnormalities of estrus and ovarian function and its control by treatment of exogenous hormones in cattle and pig. Longer estrus cycles as well as the shorter than 18 day cycles showed the lowered conception rates as compared to the normal cycles of 18 to 25 days. Other characteristics of est겨s such as duration of estrus, intensity of estrus and time of estrus are reviewed to affect fertility. The first postpartum ovulation and estrus in cows usually occurs about 20 to 30 days and 40 to 50 days after parturition, respectively. Irregularities in estrus cycle length have been conducted during early postpartum period. In sows, weaning is followed by ovulation and estrus although there is some individual variation. The most common method of estrus detection is direct visual observation on standing estrus behavior, but various aids of estrus detection have been empolyed with varying degree of effectiveness. The results from heat detector devices are about as accurate as twice-daily observation(about 90%). The abnormal estrus can be classified into three types; irregular or continuous estrus, silent estrus and anestrus. Cystic ovarian disease, follicular cysts and luteal cysts, is a serious cause of reproductive failure in cattle and pig. The follicular cysts are much more common than luteal cysts and the incidence of ovarian cysts in dairy cattle is higher than beef cattle and pig. The occurrences of ovarian cysts have been closely associated with levels of milk production, stages of postpartum period, nutritional levels and seasons. The luteal cysts and persistent corpora lutea are responsive to the luteolytic effects of the recently synthetic analogues of PGF2$\alpha$ in cows and sows and recently GnRH or LH-RH has been successfully used as a treatment for cows and sows with ovarian follicular cysts.

• Journal of Animal Science and Technology
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• 제59권5호
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• pp.12.1-12.7
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• 2017

Background: Despite the widespread use of dexamethasone in veterinary and human medicine, it is reported to cause some severe pregnancy related side effects like abortion in some animals. The mechanism of the response is not clear but seems to be related to interspecies and/or breed difference in response which may involve alterations in the concentrations of some reproductive hormones. Methods: Twenty Sahel goats comprising 18 does and 2 bucks were used for this study. Pregnancies were achieved by natural mating after synchronization. Repeated dexamethasone injections were given at 0.25 mg/kg body weight. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested at days 28 and day 78 of gestation through caesarean section for immunohistochemical analysis using 3 pregnant does randomly selected from each group at each instant. Data were expressed as Means ${\pm}$ Standard Deviations and analyzed using statistical soft ware package, GraphPad Instant, version 3.0 (2003) and progesterone receptor (PR) were scored semi-quantitatively. Results: Dexamethasone treatments had no significant (p > 0.05) effect on progesterone and estrogen concentrations in pregnant Sahel goats but up regulated PR from 2+ to 3+ in second trimester. Conclusion: As dexamethasone adverse effect on placenta is an established fact, the lack of effect on progesterone level in this study may be due to the fact that unlike other species whose progesterone production during pregnancy is placenta - dependent, in goats is corpus luteum - dependent. Consequently dexamethasone adverse effect on placenta reported in literatures did not influence progesterone levels during pregnancy in Sahel goat. The up regulation of progesterone receptor (PR) in Sahel goat gravid uterus is a beneficial effects and that dexamethasone can safely be used in corpus luteum - dependent progesterone secreting pregnant animal species like Sahel goat and camel. Therefore source of progesterone secretions during pregnancy should be considered in clinical application of dexamethasone in pregnancy.

• Reproductive and Developmental Biology
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• 제38권1호
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• pp.9-19
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• 2014

For successful embryo implantation, the communication of the maternal endometrium with the conceptus trophectoderm is required essentially. In pigs, conceptuses undergo morphological change in length to enlarge the physical contact area with the maternal endometrium and secrete estrogen to induce the maternal recognition of pregnancy during the peri-implantation period. Conceptus-derived estrogen prevents luteolysis by conversion in direction of $PGF_{2{\alpha}}$ secretion from the uterine vasculature to the uterine lumen as well as it affects on expression of the uterine endometrial genes. In addition to estrogen, conceptuses release various signaling molecules, including cytokines, growth factors, and proteases, and, in response to these signaling molecules, the maternal uterine endometrium also synthesizes many signaling molecules, including hormones, cytokines, growth factors, lipid molecules, and utilizes ions such as calcium ion by calcium regulatory molecules. These reciprocal interactions of the conceptus trophectoderm with the maternal uterine endometrium make development and successful implantation of embryos possible. Thus, signaling molecules at the maternal-conceptus interface may play an important role in the implantation process. This review summarized syntheses and functions of signaling molecules at the maternal-conceptus interface to further understand mechanisms of the embryo implantation process in pigs.

• Reproductive and Developmental Biology
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• 제42권1호
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• pp.1-6
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• 2018

In this study, we analyzed signal transduction by equine follicle-stimulating hormone receptor (eFSHR) on sti- mulation with recombinant $eelFSH{\beta}/{\alpha}$ ($rec-eelFSH{\beta}/{\alpha}$), natural porcine FSH (pFSH), and natural human FSH (hFSH). cAMP stimulation in CHO-K1 cells expressing eFSHR was determined upon exposure to different doses (0-1450 ng/mL) of these hormones. The $EC_{50}$ value of $rec-eelFSH{\beta}/{\alpha}$ was 53.35 ng/mL. The Rmax values of $rec-eelFSH{\beta}/{\alpha}$ and pFSH were 28.12 and 2.88 ng/mL, respectively. The activity of $rec-eelFSH{\beta}/{\alpha}$ was much higher than that of natural pFSH. However, signal transduction in CHO PathHunter Parental cells expressing eFSHR was not enhanced by stimulation with natural hFSH. Thus, $rec-eelFSH{\beta}/{\alpha}$ was completely active in cells expressing eFSHR. However, natural hFSH did not invoke a signal response in cells expressing eFSHR. Particularly, natural pFSH was weakly active in the same cells. These results showed that $eelFSH{\beta}/{\alpha}$ has potent activity in cells expressing eFSHR. Thus, $rec-eelFSH{\beta}/{\alpha}$ may efficiently bind to eFSHR, where as natural hFSH does not bind to eFSHR.