• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.523-528
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• 1984

The small filefish, Rudarius ercodes, generally spawning from mid May to early October in the natural habitat, was exposed to various photoperiod and temperature regimes. These environmental effects on the gonad activity, regression and recrudescence were experimentally investigated based on the mechanism of reproductive cycle. Spawning season was initiated in the early spring with the gonad activated by long photoperiod(13L) and stimulated by compensatory temperature rising. Even when the gonad activated readily at the above critical daylength (12L to 13L)was kept back at the below if, it went on maturing. At the end of spawning period (mid September), since the shortening of daylength (12L) resulted in the gonad regression regardless of temperature, the short daylength might be related to the termination of spawning in situ. When the regressive gonad at the post spawning period was treated by the above 13L: $20^{\circ}C$ condition, it could recrudesce and bring forth even spawning. From this fact, the feasible control of annual reproductive cycle of small filefish was recognized. But even in the long daylength, the temperature above $28^{\circ}C$ was preventive of gonad maturation.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.969-976
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• 2009

Use of oocytes from prepubertal animals for in vitro embryo production holds potential application for reducing generation intervals and increasing genetic progress through embryo transfer. The objective of these studies was to compare the effect of three sperm pretreatments (prior to in vitro fertilization) and seven embryo culture protocols on fertilization rate and (or) subsequent development of in vitro fertilized embryos derived from oocytes harvested from ovaries of 1-6 month old prepubertal Boer goats in China. Cleavage rates were highest for embryos fertilized with heparin-treated versus calcium ionophore- or caffeine-treated sperm. Similar rates of blastocyst development were observed using heparin- and ionophore-treated sperm, which were higher than obtained with caffeine-treated sperm. No differences in cleavage or blastocyst rates were observed following embryo culture in basal medias (synthetic oviductal fluid (SOF), Charles Rosenkrans 1 (CR1) or tissue culture medium-199 (TCM-199)) containing 10% fetal bovine serum (FBS). Cumulus or oviductal cell co-culture did not enhance cleavage or blastocyst rates relative to culture in SOF+10% FBS. Replacement of FBS in SOF medium with 0.3% BSA increased cleavage rates, but did not increase rates of blastocyst development. Sequential culture in SOF+0.3% BSA followed by SOF+10% FBS increased blastocyst yield versus continuous culture in SOF+10% FBS and tended to increase blastocyst yield versus continuous culture in SOF+0.3% BSA. These results demonstrate a pronounced effects of sperm pretreatments and in vitro embryo culture systems on rates of blastocyst development and provide a potential protocol (sperm pretreatment with heparin and sequential embryo culture in SOF+0.3% BSA followed by SOF+10% FBS) for generation of the significant numbers of in vitro produced blastocysts from oocytes of prepubertal Boer goats necessary for application of embryo transfer in rural regions of China for distribution of Boer goat genetics.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.651-662
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• 2006

Phthalate esters that are used as plasticizers and also found at low levels in foods such as dairy products are often mentioned as suspected endocrine disrupters. The purpose of the present study is to elucidate whether perinatal exposure to di-n-butyl phthalate(DBP), diisononyl phthalate (DINP) and di-2-ethylhexyl adipate (DEHA) affects several aspects of reproductive function in rats especially sexual differentiation of the brain. To this end, the dams were provided with pulverized soy-free diet containing 20, 200, 2,000 and 10,000 ppm of DBP, 40, 400, 4,000 and 20,000 ppm of DINP, or 480, 2,400 and 12,000 ppm of DEHA from gestational day (GD) 15 to postnatal day (PDN) 21, the day of weaning, and serum sex steroid hormone, gonadotropin levels and sexual behaviors after maturation were assessed. At Postnatal week (PNW) 20-21, serum levels of sex steroids and gonadotropins in both male and female rats, as well as estrous cyclicity in females, were not changed by perinatal exposure to DBP, DINP and DEHA, indicating that these chemicals did not affect sexual differentiation of the brain controlling the endocrine system of hypothalamo-pituitary-gonadal (HPG) axis. On the other hand, inhibitory influences on sexual behaviors, especially on ejaculation in males and lordosis in females, were observed by perinatal exposure to these chemicals. These results suggest that these chemicals may act directly on discrete regions of the hypothalamus regulating sexual behaviors, but not regulating gonadotropin secretion, thereby affect sexual differentiation of the brain with a resultant decrease in sex-specific behaviors in adulthood.

• Reproductive and Developmental Biology
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• v.30 no.3
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• pp.181-187
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• 2006

In recent years the number of patients waiting for organ transplantation has greatly outpaced the supply of human organs available, which leads to a renewed interest in pig-to-human xenotransplantation as an alternative. However, one of the biggest barriers in the xenotransplantation is presence of porcine endogenous retroviruses(PERV) that can infect human cells. In this study, to present a possible solution for this problem we tried to inhibit expression of PERVs using shRNAs(short hairpin RNA) at the level of RNA synthesis and virus release. The shRNA targeting the sequence of PERV A, B type was cloned into pSIREN-RetroQ vector under the control of polymerase-III U6-RNA gene promoter. Quantitative real-time PCR was performed to detect my alterations in mRNA production of PERV A, B targeted by the shRNA in each done. Depending on the target sequence of the shRNA, the transcription of PERV was decreased to as much as 4% and the number of progeny viruses was reduced to less than 1/200,000. Transgenic pigs producing such shRNAs may result in a highly reduced PERV expression in cells and organs, which is a prerequisite for safe xenotransplantations.

• Clinical and Experimental Reproductive Medicine
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• v.44 no.4
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• pp.214-223
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• 2017

Objective: In vitro fertilization (IVF) is a well-known method for the treatment of infertility. The present study aimed to compare the differences between infertile women with successful and unsuccessful IVF outcomes regarding the expression of T helper (Th) cell transcription factors and a group of related cytokines before and after exposure to their husbands' seminal plasma. Methods: This study was performed on 19 couples with unexplained infertility undergoing IVF treatment. Among the studied group, nine and 10 couples had successful and unsuccessful IVF outcomes, respectively. This study was carried out using real-time polymerase chain reaction. Results: Before seminal plasma exposure, the expression levels of T-bet (p< 0.007), $interferon-{\gamma}$ (p= 0.013), and tumor necrosis factor $(TNF)-{\alpha}$ (p= 0.017) were higher in the infertile women with IVF failure than in those with successful IVF outcomes, while those of GATA3 (p< 0.001), Foxp3 (p= 0.001), and interleukin (IL)-35 (p< 0.003) were lower. After seminal exposure, the expression of T-bet (p= 0.02), Rorc (p< 0.001), $TNF-{\alpha}$ (p= 0.001), Foxp3 (p= 0.02), and $interferon-{\gamma}$ (p= 0.001) increased in the unsuccessful IVF group, while the expression of Foxp3 (p= 0.02), Rorc (p< 0.001), IL-23 (p= 0.04), IL-17 (p= 0.02), IL-6 (p< 0.001), transforming growth $factor-{\beta}$ (p= 0.01), and IL-35 (p< 0.001) increased in the successful IVF group. Conclusion: In summary, IVF failure was associated with imbalanced Th1/Th2/Th17/Treg responses. Moreover, our results show that seminal plasma might have a positive effect on IVF outcomes via changes in peripheral blood T cell subsets.

• Journal of Embryo Transfer
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• v.29 no.2
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• pp.183-188
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• 2014

A study was carried out on 16 indigenous ewes in Bangladesh in order to assess the reproductive physiology, the pattern of vaginal cell exfoliation and progesterone profiles during the estrous cycle period. The mean estrous cycle length and duration of estrus were $15.8{\pm}0.12$ days and $31.1{\pm}0.57$ h respectively. The exfoliated epithelial cells were categorized into parabasal, intermediate, superficial and keratinized and their relative occurrences. The percentages of parabasal, intermediate and superficial cell type during proestrus were similar. The percentage of superficial cell type during estrus was 61.7%, which was significantly (p<0.01) differ from other types of cells and stages of estrus cycle. Metoestrus was predominant with neutrophils in addition with other cell types. Dioestrus was dominated by neutrophils. On days 0 to 5 of the cycle the progesterone concentration was 0.09 to $1.6{\pm}0.07ng/ml$. The length of diestrus was 5~10 days with a range of mean progesterone level of $1.6{\pm}0.07$ to $2.8{\pm}0.11ng/ml$. Progesterone levels increased significantly (p<0.01) after Day 5 and maximum level was $2.8{\pm}0.11ng/ml$ observed on Day 10 of the estrous cycle. Thereafter it dropped rapidly to basal level of $0.11{\pm}0.04ng/ml$ on Day 0 (p<0.01). These results indicate that the pattern of exfoliation of vaginal cells along with progesterone concentration could be used to determine the reproductive stages of indigenous ewe.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.1007-1012
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• 2010

The aim of the present study was to describe whether abnormal cervical mucus discharge (A-CMD) or pathogens in cervical mucus discharge (CMD) have effects on reproductive performance of cows and heifers in estrus. Animals having clear discharges (68 cows, 38 heifers) with normal viscosity and without bad odor were grouped as normal cervical mucous discharge (N-CMD) group. The other animals (84 cows, 32 heifers) were grouped as A-CMD group. Microorganisms isolated from samples were divided into three groups as uterine pathogens (UP), potential uterine pathogens (PUP) or opportunistic uterine pathogens (OUP). Presence of PUP was associated with A-CMD for both cows (p<0.01) and heifers (p<0.02). First service conception rates (FS-CR) were lower in cows positive for PUP (p<0.01). Moreover, presence of PUP and OUP affected FS-CR in heifers (p<0.01). Although A-CMD significantly affected FS-CR in cows (p<0.04), it did not affect FS-CR in heifers. Differences in average open day for cows (p<0.02) and first service age for heifers (p<0.01) were significant between N-CMD and A-CMD groups, respectively. The current study suggested that CMD should be evaluated more carefully when there are infertility problems. In addition to the known microorganism that causes sterility and infertility in the UP group, pathogens in the PUP group should be considered for their potential to cause infertility.

• Reproductive and Developmental Biology
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• v.37 no.1
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• pp.29-33
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• 2013

The objective of this work was to analyze the concentrations of progesterone (P4) and estrogen (E2) hormones changed during estrus synchronization in dairy heifers. Estrus synchronization was carried out with CIDR$^{(R)}$ (Controlled Intravaginal Drug Release) devices. Corpus luteum (CL) was classified into three grades based on its size and palpable characteristics. The concentrations of P4 and E2 were measured by enzyme-amplified chemiluminescence. Serum P4 concentration was markedly low at the estrus stage (36 hrs after removal of CIDR) compared to other stages, while E2 concentration was kept high during estrus stage. The serum P4 concentration was highest in the CL classified into grade I. These results indicate that P4 concentration could be used as a criteria for determining recipients for artificial insemination or embryo transfer in dairy cattle.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.2
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• pp.131-140
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• 2001

Objective: To know the effects of xenoestrogen on spermatogenesis, we investigated the expression of cytochrome P450s enzymes (CYPscc, $CYP_{17{\alpha}}$, CYP19) and $3{\beta}$-HSD genes involved in steroidogenesis. Methods: Mouse testicular cells were prepared from 15-day-old ICR mice which had only pre-meiotic germ cells by enzyme digestion using collagenase and trypsin. Testicular cells were cultured in DMEM supplemented with FSH (0.1 IU/ml) and 10% FBS or medium with estrogen ($E_2$), bisphenol-A (BPA), octylphenol (OP; $10^{-9},\;10^{-7},\;10^{-6},\;10^{-5},\;10^{-4}M$, respectively) and aroclor 1254 (A1254) known as PCBs for 48 hours. The gene expression of cytochrome P450 enzymes were examined by semi-quantitive RT-PCR. The production of estrogen and testosterone was examined by RIA. Results: As results, expression of CYPscc mRNA was not significantly decreased, but $3{\beta}$-HSD and $CYP_{17{\alpha}}$. mRNA were significantly dose-dependent decreased. And production of testosterone and estrogen were not different except BPA and OP group ($10^{-5}M$). Conclusion: BPA, OP and A1254 might inhibit steroidogenesis by decreasing CYPscc, $3{\beta}$-HSD and $CYP_{17{\alpha}}$. mRNA expression in the mouse testis. These results suggest that BPA, OP and PCBs like as an endocrine disruptors inhibit the productions of steroidogenic enzymes and decrease the production of T and E by negative feedback mechanism. Therefore, these might disrupt steroidogenesis in Leydig cells of testis and would disturb testicular function and subsequently impair spermatogenesis.

• Ocean and Polar Research
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• v.37 no.1
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• pp.37-47
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• 2015

The effects of low salinity (fertilization success and larval survival) on the limpet Cellana grata were studied at early stages of development using the marine bioassay technique. It was shown that, under normal conditions for development from fertilization to the post veliger stage, the salinity must be not less than 20.0~35.0 psu. However, the fertilization rate and larval survival of C. grata was obviously reduced at 5.0 psu and 10.0 psu, respectively. Mass mortality was estimated to occur at <20.0 psu (48-h $EC_{50}=19.54psu$) and the survival rate of normal veliger larvae decreased with experimental time during exposure. No observed effective concentration (NOEC) and lowest observed effect concentration (LOEC) of post veliger were estimated at 30.0 psu and 25.0 psu, respectively, during 48-h exposure. The tolerance limits of the test species to salinity revealed various concentration ranges of salinity, which may reflect the physiology and ecology of the initial development stages of C. grata. These results demonstrate that reduced salinity is detrimental to the reproductive success and larval survival of C. grata, and if salinity is lowered by natural or anthropogenic sources during spawning, this would lead to decreased reproductive success and larval settlement.