Animal reproduction science Journal Impact Factor & Information

Publisher: Elsevier Masson

Current impact factor: 1.51

Impact Factor Rankings

2015 Impact Factor Available summer 2016
2014 Impact Factor 1.511
2013 Impact Factor 1.581
2012 Impact Factor 1.897
2011 Impact Factor 1.75
2010 Impact Factor 1.721
2009 Impact Factor 1.563
2008 Impact Factor 1.89
2007 Impact Factor 1.739
2006 Impact Factor 2.186
2005 Impact Factor 2.136
2004 Impact Factor 1.41
2003 Impact Factor 1.286
2002 Impact Factor 1.681
2001 Impact Factor 1.196
2000 Impact Factor 1.08
1999 Impact Factor 0.813
1998 Impact Factor 1.105
1997 Impact Factor 0.93
1996 Impact Factor 0.838
1995 Impact Factor 0.709
1994 Impact Factor 0.855
1993 Impact Factor 0.678
1992 Impact Factor 0.701

Impact factor over time

Impact factor

Additional details

5-year impact 1.86
Cited half-life 7.90
Immediacy index 0.19
Eigenfactor 0.01
Article influence 0.47
ISSN 1873-2232

Publisher details

Elsevier Masson

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    • Publisher last reviewed on 01/05/2015
    • 'Elsevier Masson' is an imprint of 'Elsevier'
  • Classification

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: Bothrops insularis is an endemic and critically endangered snake with an estimated population of 2000 individuals restricted to Queimada Grande Island, in southeastern Brazil. Brazilian researchers established a captive breeding program for the species that includes the application of assisted reproductive technologies. The present study, therefore, aimed to evaluate semen samples from captive B. insularis throughout the year to ascertain seasonal differences in semen traits as well as correlations with body size and weight. Eighteen males with snout-vent length (SVL) ranging from 43.5 to 73.7cm were collected at quarterly basis between August 2012 and May 2013. Macroscopic analysis revealed semen volumes ranging from 0.5 to 6.0μL with samples featuring whitish to yellowish color and creamy and thick consistency. Viable sperm was obtained from all males indicating that individuals with SVL equal to or greater than 43.5cm are sexually developed. However, adult and immature males (estimated by SVL) exhibited different seasonal profiles for motility and progressive motility. Adult males had a decrease in sperm motility and progressive motility during summer and spring, respectively, whereas the same variables did not vary throughout the year in immature snakes. Sperm concentration in all individuals was less (0.5×10(9)μL) during the winter, but no seasonal fluctuations were detected in semen volume. These findings are of particular importance to the development of reproductive tools such as male selection, artificial insemination and sperm freezing for the genetic management of this critically endangered snake.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.10.012
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    ABSTRACT: The aim of this research was to study the effect of different genistein treatments on bull sperm after thawing on pronuclear formation after in vitro fertilization (IVF) and on different sperm quality variables. Three experiments were performed. In Experiment 1, three treatments (Control, sperm incubation for 1h at 37°C with or without genistein) and two sperm concentrations during IVF (1 or 3×10(6)sperm/mL) were evaluated to study the influence of genistein on pronuclear formation (PNF). Sperm incubation for 1h before IVF reduced PNF regardless of sperm concentration. However, after sperm incubation and with 3×10(6)sperm/mL in IVF, the genistein treatment group had greater fertilization rates than the untreated group. In Experiment 2, six treatments plus the control group were performed to study the effect of genistein (presence or not) and incubation conditions (30min at 37°C, 1h at 27°C or at 37°C) on PNF using 3×10(6)sperm/mL for IVF. When incubation time was reduced to 30min, PNF rate from the genistein treatment group was no different from either the control group or in the group in which incubation occurred for 1h at 27°C. In Experiment 3, the effect of several genistein treatments (control; genistein treatment for 30min of incubation at 37°C; genistein treatment for 1h of incubation at 27°C) on sperm motility, viability and DNA fragmentation were evaluated. Genistein did not improve sperm motility and, depending on the experimental group or time, it either reduced or had no effect on sperm motility. Genistein treatment did not improve sperm viability after 5h of incubation. However, genistein treatment for 1h at 27°C decreased sperm DNA fragmentation compared with the control group after 5h of sperm incubation. In conclusion, the treatment of bull sperm with genistein for 1h at 27°C could decrease sperm DNA fragmentation, although PNF rate after IVF and sperm motility were reduced.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.10.006
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    ABSTRACT: We evaluated the capacity of ocelot and oncilla spermatozoa to bind to the perivitelline membranes (PVMs) of hen eggs in a sperm binding assay (S-PVM). In addition, a device that improves the standardization of the assay was developed. The number of sperm bound to the PVM in fresh (T1) and frozen-thawed (T2) semen from both species was compared to the sperm quality observed in routine tests. The PVM was stretched on a circular silicone device to create a standardized area for analysis. In both treatments and for both species, the spermatozoa were able to bind to the PVM, indicating that PVM may be used for a sperm binding assay in ocelot and oncilla. The S-PVM assay did not differ in fresh and frozen-thawed ocelot sperm (p>0.05). However, fewer oncilla sperm (p<0.05) were bound to the PVM in T2, indicating that the proposed test may be able to detect injuries that compromise sperm binding abilities. The device maintained the PVM stretched during the processing and defined the evaluation area.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.09.018
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    ABSTRACT: The multiple ovulation and embryo transfer (MOET) technique has become an important breeding method in modern animal selection programs and a reproductive technique that can bypass ovarian dysfunction caused by heat stress to maintain reproductive performances in dairy cows. However, oocyte and embryo development often suffer from defects following repeated superovulation protocols. This phenomenon might be attributed to high levels of circulating inhibin, which is secreted by the supra-normal numbers of developing follicles during the process of superovulation. Through inhibin's negative impact on ovarian follicle development, high concentrations of inhibin might reduce oocyte quality and embryo developmental competence. Neutralizing endogenous inhibin bioactivities by active or passive immunizations against inhibin has been demonstrated to stimulate extra follicle development and induce multiple ovulations in both rodents and ruminants. Combined with conventional superovulatory protocols, immunization against inhibin further enhances follicle development and embryo yield. Furthermore, immunization against inhibin not only enhanced embryo quantity but also embryo quality in studies conducted in cows, sheep and water buffaloes. Similar beneficial effects on enhancing embryo development quality have been demonstrated in in vitro studies, where treatment with inhibin α subunit antibody enhances oocyte maturation and development of IVF or parthenogenically activated embryos. Thus, immunization against inhibin in combination with a conventional superovulation protocol can become a new technique to improve embryo production efficiency in vivo, as well as to develop a new oocyte IVM/IVF technique that can improve embryo IVP production efficiency.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.001
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    ABSTRACT: The aim of the study was to determine the effect of antibiotics on quality parameters and fertilizing capacity of boar sperm during liquid preservation. In the first experiment, semen was diluted in an extender containing 200μg/mL of gentamicin as a control and diluted in a modified extenders: Ext I (contained 200μg/mL florfenicol), Ext II (contained 200μg/mL polymyxin B), Ext III (contained 100μg/mL gentamicin and 100μg/mL florfenicol) and Ext IV (contained 100μg/mL gentamicin and 100μg/mL polymyxin B). The semen was stored for ten days. Sperm quality was evaluated based on the motility (CASA; TM: total motility; PM: progressive motility), membrane integrity (YO-PRO-1/PI assay), mitochondrial activity (JC-1) and DNA integrity (TUNEL). The highest PM% (62.5±9.6) was observed in Ext III at Day 6 of storage. The highest sperm viability and mitochondrial transmembrane potential was noticed at the end of the storage period in Ext III. Long-term storage did not induce DNA fragmentation in the extenders analyzed. In the second experiment, semen diluted in the control extender and in the extender providing the highest quality spermatozoa on Day 10 (Ext III) was used for artificial insemination (AI) of synchronized gilts. Our studies showed that the highest reproductive performance of inseminated gilts (pregnant gilts: 97.0%, litter size: 11.4±1.2) occurred with Ext III semen dilution. The combination of 100μg/mL gentamicin and 100μg/mL florfenicol in the extender maintained sperm motility, membrane integrity and mitochondrial activity and enhanced the higher reproduction success.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.005
  • [Show abstract] [Hide abstract]
    ABSTRACT: We compared the effects of extenders of frozen-thawed semen on post-thaw sperm characteristics and the distribution of frozen-thawed spermatozoa in the female genital tract after fixed-timed deep intrauterine insemination (DIUI) in sows. Frozen semen samples were thawed and diluted in either modified Modena solution (mMS) or porcine fertilization medium (PFM) containing theophylline, adenosine and cysteine. Sperm quality, assessed in vitro based on motility using a computer-assisted sperm analyzer and the integrity of the plasma and acrosomal membranes using flow cytometry, was evaluated at 0.5, 1.5, 3 and 6h after thawing. Progressive motility and the percentage of spermatozoa with damaged acrosomal membranes in PFM were significantly better than in mMS throughout the 6h. Sows with estrus synchronized using prostaglandin F2 alpha, equine chorionic gonadotropin and human chorionic gonadotropin (hCG) were inseminated once with mMS- or PFM-diluted 5×10(8) frozen-thawed spermatozoa by DIUI at 34h after the hCG injection. At 4h after DIUI, reproductive tracts were recovered from 30 sows. There were significantly fewer polymorphonuclear leukocytes (PMNs) and more spermatozoa outside PMNs in the uterine horn after PFM treatment than with mMS. When 22 sows were administered DIUI with 10×10(8) frozen-thawed spermatozoa at 36h after hCG, the pregnancy rates did not differ significantly between the mMS- (36%) and PFM- (64%) treated groups. Thus, PFM enhanced progressive sperm motility but increased sperm membrane damage compared with mMS; it also suppressed the migration of PMNs into the uterine lumen.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.006
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    ABSTRACT: During the last decades fundamental and applied aspects of mammalian ram sperm cryopreservation have been increasingly explored by scientists and biotechnologists. Many works report modifications in the composition of the freezing extenders and explore the beneficial and detrimental effects of seminal plasma or seminal plasma components in cryopreservation. Seminal plasma is known to contain stabilizing proteins, thereby this is a good start point to study the maintenance of membrane stability based on the basic knowledge of sperm physiology. However, seminal plasma composition is variable among rams and also the introduction of exogenous seminal plasma or its fractions to commercial semen can be associated with the transmission of viral diseases. Our work shows that a mouse protein, called SPINK3 (Serine Protease Inhibitor Kazal type 3) with decapacitating activity interacts with heterologous ram sperm when it is produced as a recombinant molecule. By immunocytochemistry assays we demonstrate that this protein (naturally expressed by mouse seminal vesicle under androgenic control) binds to the apical portion of both fresh and frozen ram sperm, the same localization described in mouse homologous sperm. Furthermore, it significantly improves sperm progressive motility compared to non-treated samples when it is added to freezing extenders and to dilution media after thawing. On the contrary, addition of SPINK3 does not modify sperm viability. The percentage of sperm with intact acrosome after ionophore induction was also significantly higher in sperm frozen in the presence of SPINK3 compared to control samples and the addition of SPINK3 after thawing significantly reduced both induced and non induced acrosomal loss, indicating that heterologous SPINK3 might act as a calcium inhibitor transport as described in mouse. Based on our results SPINK3 may find a place as a desirable biotechnological tool to achieve a higher proportion of competent sperm to fertilize.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.007
  • [Show abstract] [Hide abstract]
    ABSTRACT: A specific problem in goat semen preservation is the detrimental effect of seminal plasma on sperm viability in extenders containing yolk or milk. Thus, the use of chemically defined extenders will have obvious advantages. Although previous studies indicate that the initial pH of an extender is crucial to sustain high sperm motility, changes in extender pH during long-term semen storage have not been observed. Monitoring extender pH at different times of semen storage and modeling its variation according to nonlinear models is thus important for protocol optimization for long-term liquid semen preservation. The present results showed that during long-term liquid storage of goat semen, both sperm motility and semen pH decreased gradually, and a strong correlation was observed between the two. Whereas increasing the initial extender pH from 6.04 to 6.25 or storage with stabilized pH improved, storage with artificially lowered pH impaired sperm motility. Extender renewal improved sperm motility by maintaining a stable pH. Sperm coating with chicken (Gallus gallus) egg yolk improved motility by increasing tolerance to pH decline. A new extender (n-mZAP) with a higher buffering capacity was formulated, and n-mZAP maintained higher sperm motility, membrane integrity and acrosome intactness than the currently used mZAP extender did. Goat semen liquid-stored for 12 d in n-mZAP produced pregnancy and kidding rates similar to those obtained with freshly collected semen following artificial insemination. In conclusion, maintenance of a stable pH during liquid semen storage dramatically improved sperm viability and fertilizing potential.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.011
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    ABSTRACT: Acrosin Binding Protein (ACRBP) is specifically localized in the acrosome of germ cells of several species, including mice, pigs, guinea pigs, and humans. The main objective of this study was to investigate ACRBP patterns in the germ cells of stallions at different reproductive stages and seminiferous tubule stages using Western blot, immunohistochemistry, and immunocytochemistry techniques. The stallion reproductive stages were classified as follows: pre-pubertal and post-pubertal stages based on the presence/absence of lumen opening in the seminiferous tubules and full spermatogenesis. The protein band associated with the presence of ACRBP appeared at approximately 35-kDa position, indicating that the antibody used in this study recognizes the mature form of ACRBP. During the pre-pubertal stages, immunolabeling did not detect the presence of ACRBP in the germ cells. However, during the post-pubertal stage, immunolabeling of the ACRBP was observed in the pachytene spermatocyte as well as for round, elongating, and elongated spermatids, and in some spermatozoa. In conclusion, the ACRBP can be used as a molecular marker for pachytene spermatocytes, and for round, elongating, and elongated spermatids. The ACRBP can be used to monitor either normal spermatogenesis in the testicular tissues, or germ cell development in vitro. Because the ACRBP is present in the germ cells of stallions that have undergone puberty, it can be used as an indicator for the sexual maturation of stallions.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.010
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    ABSTRACT: In this study, to clarify the relationship between ovarian reserve and oocyte quality, cumulus-oocyte complexes (COCs) were collected repeatedly by ovum pick-up (OPU) from cows with high and low antral follicle counts (AFCs) at short (3-4 days) and long (7 days) intervals, and COC morphologies and oocyte fertilizability were examined. The relationship between AFC and follicular growth after OPU was also investigated. Cows showing AFC of ≥30 in at least one OPU session were grouped into the high-AFC group. At a short interval, follicular sizes and COC morphologies were similar between the different AFC groups. However, the normal fertilization rate was higher in the high-AFC group than in the low one, although total penetration rates were similar. At a long interval, the percentage of COCs with poor morphology in the high-AFC group was higher and the normal fertilization rate was lower than in the low one. In the low-AFC group, normal fertilization rates at short and long intervals were similar, and mean follicular size became larger at a long than at a short interval. However, mean follicular sizes at short- and long-interval OPU were similar in the high-AFC group. In conclusion, it is suggested that oocytes derived from cows with high AFC had higher fertilizability than those from cows with low AFC when OPUs were performed at a short (3-4 days) interval. However, oocyte quality in high-AFC cows was impaired by long-interval (7 days) OPU, possibly due to the degradation of follicles.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.009
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    ABSTRACT: The aim of this study was to examine the seasonal changes in concentration of steroid hormones in the spermatic cord vessels of the mature boar. Cytochrome P450 aromatase (P450arom) was also localized in the arteries and veins of the spermatic cord. Arterial blood was collected from the common carotid artery and from two branches of the testicular artery supplying the testis and epididymis to determine progesterone (P4), androstenedione (A2), testosterone (T2) and estradiol (E2) plasma concentrations. The greatest concentration of P4 was found in testicular artery during December (P<0.001), when compared with other periods and vessels. In contrast, the greatest A2 concentration was observed in the epididymal artery during the same season (P<0.001). Greater T2 concentrations were found in both testis and epididymal arteries than in common artery in March (P<0.001, P<0.001; respectively) and in September (P<0.01, P<0.001; respectively). The E2 concentration was weakly affected by seasonal periods, but greater E2 concentrations were found within vessels in the testis and epididymis than in the common artery. The P450arom was immunolocalized in all layers of the arteries and veins of the testicular spermatic cord. The intensity of P450arom staining was greater in December than in June (P<0.001). There were greater steroid concentrations in arterial vessels during December in comparison to June and this may explain the summer infertility in boars and may be related to the local retrograde and destination transfer into the spermatic cord area. The P450arom gene expression in this area seems to be involved in the conversion of T2 into E2 to enrich the testes and epididymis.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.10.009
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    ABSTRACT: NLRP (NLR family, Pyrin domain containing) genes have both immunization- and reproduction-related clades in mammals. Nlrp5 is a reproduction-related gene, originally identified in the mouse, which plays a key role in mouse early embryogenesis. Previous studies estimated that the porcine NLRP5 gene is assigned to the long arm of chromosome 6 and expressed in oocytes. However, the expression pattern of the NLRP5 gene in the porcine reproductive tract, and the localization and function of NLRP5 protein in porcine preimplantation embryos are still unknown. Here, we show that NLRP5 transcripts and protein are detected exclusively in the ovary in the porcine reproductive tract. Furthermore, the transcripts display a sharp decline in porcine preimplantation embryos before zygotic genome activation, but the protein remains present through to the blastocyst stage, localize in the cytoplasm and close to the subcortex of porcine oocytes and preimplantation embryos. Moreover, the knockdown of NLRP5 expression in zygotes using RNA interference arrested early embryonic development. These results provide the first evidence that the NLRP5 gene is required for early embryogenesis in sows, suggesting that this gene might play an essential role in zygotic genome activation.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.004
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    ABSTRACT: Insufficient placenta development is one of the primary causes of fetal death and reduced fetal growth after 35 days of gestation. Between day 22 and 42 the placenta consists of a central highly vascular placenta (HVP), adjacent to the fetus, a less vascular placenta (LVP), on either side of the fetus, and necrotic tips (NT). The objective of this study was to comprehensively evaluate uterine-placenta characteristics during early gestation in the gilt and determine time points and physiological changes. Gilts (n=25) were artificially inseminated at first detection of estrus (day 0) and 24h later, and harvested at 22, 27, 32, 37 or 42 days of gestation. Litter size, 12.1±3.4, was similar for all days of gestation. Fetal and placenta weight increased with day of gestation. The greatest increase in placenta weight occurred between 37 and 42 days of gestation. The LVP zones had no measurable fold formation until day 27. Necrotic tips became apparent after 27 days of gestation. Unoccupied areas of the uterus developed folds with changes in endometrial cell size and morphology from day 32 to 42 of gestation. Limited changes occurred in either fetal growth or placenta weight from day 27 through 32 of gestation; however, significant morphological changes occur at the maternal-fetal interface, demonstrating the dynamic architecture of the developing porcine placenta during early gestation. This work establishes fundamental time points in placenta development corresponding to fetal growth and microfold formation that may influence fetal growth and impact fetal survival.
    Animal reproduction science 11/2015; DOI:10.1016/j.anireprosci.2015.11.002
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    ABSTRACT: There are limited studies available on when to inseminate, if using CIDR or CIDR-GnRH protocols for optimal fertility in buffalo. Therefore, the objective of the present study was to determine the optimum time of AI in relation to CIDR removal with or without GnRH in buffalo. All buffalo (n=201) received CIDR on Day 0, PGF2α on Day 6 and CIDR were removed on Day 7. In 50 of these buffalo GnRH was administered 36h after CIDR removal. Furthermore, CIDR (n=151) and CIDR-GnRH (n=50) were randomly divided to receive timed artificial insemination (TAI), either at 48, 60 or 72h after CIDR removal. Ultrasonography was performed for follicular development and for pregnancy diagnosis. The results revealed that, mean interval to ovulation was shorter (P<0.05) in buffalo receiving CIDR-GnRH than CIDR (68.40±1.73 compared with 76.13±1.66h, respectively). The pregnancy rates were higher (P<0.05) in buffalo inseminated either at 48 (50%) or 60 (59%) than at 72h (18%) in CIDR-GnRH protocol; whereas, in CIDR buffalo pregnancy rates were higher (P<0.05), at 60 (37%) or 72 (40%) than at 48h (10%). In conclusion, the optimal time of AI is between 48-60h in CIDR-GnRH and between 60-72h in CIDR protocol for enhancing fertility in buffalo.
    Animal reproduction science 10/2015; DOI:10.1016/j.anireprosci.2015.09.010
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    ABSTRACT: Follicle-stimulating hormone regulation of ovarian estradiol (E2) production requires involvement of beta-catenin (CTNNB1), a transcriptional co-factor. In cultured granulosa cells (GC) of cattle, FSH treatment increased protein abundance of CTNNB1 as well as protein kinase B (AKT), a molecule known to regulate components of the CTNNB1 degradation complex. However, whether FSH induction of CTNNB1 is through direct modulation of AKT remains to be determined. To investigate specific contributions of AKT to CTNNB1 accumulation, GC were treated with insulin-like growth factor-I (IGF-I), a well-established AKT activator, in the presence or absence of FSH. Granulosa cells treated with FSH, IGF-I, and IGF-I plus FSH had increased CTNNB1 accumulation compared with controls (P≤0.02; n=6). E2 medium concentrations were greater (P=0.09; n=4) in FSH treated cells compared to controls (166 and 100±28pg/mL, respectively). Treatment with IGF-I and IGF-I plus FSH increased (P<0.01) E2 to comparable concentrations. Subsequently, GC treated with lithium chloride (LiCl), a pharmacological activator of AKT, provided a response consistent with IGF-I treated cells, as LiCl, FSH, and FSH plus LiCl increased CTNNB1 accumulation compared with non-treated controls (P≤0.03; n=3). In contrast, inhibition of AKT signaling with LY294002 suppressed the ability of FSH and IGF-I to regulate CTNNB1. Additionally, LY294002 treatment reduced FSH and IGF-I mediated E2 medium concentrations (P≤0.004). These results demonstrate that activation of AKT is required for gonadotropin regulation of CTNNB1 accumulation and subsequent ovarian E2 production.
    Animal reproduction science 10/2015; DOI:10.1016/j.anireprosci.2015.10.003
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    ABSTRACT: The P-element induced wimpy testis (Piwi) protein family, a subfamily of the Argonaute protein family, is involved in gene silencing and shows specific expression in spermatogenic cells. To reveal the transcriptional regulatory mechanisms of Piwil1 in chickens, we cloned sequences of the chicken Piwil1 promoter region and performed luciferase reporter and electrophoretic mobility shift assays to analyze the transcriptional activity and identify important transcriptional regulatory elements. The results showed that the region from -90 to -43 in the 5'-flanking region of Piwil1 contains a transcriptional regulatory CCAAT box that was necessary for the transcriptional activity of the Piwil1 promoter. Moreover, the transcription factor nuclear factor Y (NF-Y) was bound to the Piwil1 promoter CCAAT box specifically in germ cells. In addition, bisulfite sequencing to determine the methylation profile of the Piwil1 promoter CpG island in different spermatogenic and non-germ cell populations was performed. Compared with germ cells, non-germ cells showed increased methylation of the promoter region containing the CCAAT box, loss of NF-Y binding, and silencing of the Piwil1 locus. It is demonstrated that the specific expression of Piwil1 in chicken germ cells is regulated by the transcription factor NF-Y and differential CpG island methylation.
    Animal reproduction science 10/2015; 162. DOI:10.1016/j.anireprosci.2015.09.016