<p>Involuntary childlessness is a big problem around the world. One way to solve the problem is to receive oocytes or semen from a donor. In Sweden, semen donation has been regulated by law since 1985 and oocyte donation since 2003. The aim of this study was to investigate what motivations women and men in Sweden have to donate gametes, if they feel any ambivalence to donate, and to compare if there is any difference in motivation and ambivalence between women and men. Motivation was measured with eight statements based on previous results and clinical experience. Ambivalence was measured with a scale consisting of seven statements that addressed thoughts and feelings about the donation. The participants in the study were donors at some of the seven infertility clinics in Sweden. The dropout rate for the sperm donors was 19 %. For the egg donors the dropout rate was 17 %.. The main result showed that the main motivation for donating oocytes or semen was helping childless couples. The significant differences between women’s and men’s motivations for donating oocytes or semen were that the women were keener to helping others, while the men to a higher extent wanted to do something important, spread their genes and find out about their own fertility. The oocyte and semen donors did not feel any particular ambivalence about the decision to donate, most of them did not find it difficult to make the decision, and they would have been disappointed if they had not been allowed to donate for some reason. The conclusions to be drawn from this study are that once the donors have decided to donate, they don’t feel any particular ambivalence about the donation, and women and men have different motivations to why they are donating, even if the main motivation is the same.</p> / <p>Ofrivillig barnlöshet är ett stort problem världen över. Ett sätt att lösa problemet är att ta emot ägg eller spermier ifrån en donator. I Sverige har spermiedonation varit reglerat i lag sedan 1985 och äggdonation sedan 2003. Syftet med denna studie var att undersöka vilka motiv kvinnor och män i Sverige har till att donera ägg respektive spermier, om de känner någon ambivalens till att donera, samt att jämföra om det är någon skillnad i motiv och ambivalens mellan kvinnor och män. Motiv mättes med åtta påståenden konstruerade utifrån tidigare resultat och klinisk erfarenhet. Ambivalens mättes med en skala som bestod av sju påståenden som behandlade tankar och känslor kring donationen, Deltagarna i studien var donatorer vid någon av de sju infertilitetscentra i Sverige. Bortfallet för spermiedonatorerna var 19 %. För äggdonatorerna var bortfallet 17 %. Huvudresultatet visade att det främsta motivet hos kvinnor och män till att donera ägg respektive spermier i Sverige var att hjälpa barnlösa par. De signifikanta skillnaderna mellan kvinnors och mäns motiv till att donera ägg respektive spermier var att kvinnor var mer måna om att hjälpa andra, medan männen i högre grad ville göra något betydelsefullt, sprida sina gener och få reda på hur det stod till med den egna fertiliteteten. Ägg- och spermiedonatorerna kände ingen större ambivalens inför beslutet om att donera, de flesta tyckte inte att beslutet var svårt att ta, och de skulle ha blivit besvikna om de inte fick donera av någon anledning. Slutsatser som har dragits är att när ägg- respektive spermiedonatorer väl har bestämt sig för att donera känner de ingen större ambivalens inför donationen, och män och kvinnor har skilda motiv till varför de donerar även om huvudmotivet är detsamma.</p>

Pig follicle development is a complex but poorly understood process involving both gonadotrophins and local ovarian factors. A series of studies sought to investigate these intrafollicular cell-to-cell interactions. Microarray analysis combined with gene ontology revealed that the oocyte, granulosa and theca cells each expressed more than 650 potential secreted factors and receptors, including members of the TGF-β, IGF1, EGF and FGF families. Using a well-defined in vivo experimental paradigm that generates follicles and oocytes of different quality, the temporal expression of several growth factors in the oocyte, granulosa and theca cells collected from sows during the recruitment and mid-selection phases, as well as the final selection of the preovulatory follicle population before and after the LH surge was studied. IGF1 expression patterns indicated its potential for modulating granulosa and theca cell function during the selection stages, and an involvement in creating differences in follicular quality between the first and second preovulatory wave post-weaning. Transient up-regulation of AREG and EREG mRNA around the LH surge, suggested their involvement in ovulation. Results of a second study investigating TGF-β superfamily expression, suggested a role for GDF9 in follicle selection through the up-regulation of TGFBR1 expression, while BMP15 could be involved in ovulation through the up-regulation of BMPR1B. Expression of angiogenesis-related genes during follicle development was also investigated. During mid-selection, ANGPT2 may allow VEGFA and similar factors to stimulate vascular development or destabilize the vasculature and cause follicular atresia, while ANGPT1 may be required in the preovulatory follicle population. Associations among the transcription factor HIF1A, VEGFA and ANGPT1, suggested interactions between the ligands in regulation of angiogenesis. Finally, the effects of the pig oocyte on cumulus cell function was assessed by co-culturing cumulus cell complexes with or without denuded oocytes isolated from large oestrogenic follicles. Presence of oocytes decreased FSHR and increased HSD3B expression, potentially stimulating progesterone while attenuating oestradiol production. In conclusion, oocytes were shown to control cumulus cell function in a way that reflects their specific environment and further evidence was obtained for a complex network of growth factors and receptors in the follicle and their involvement in regulation of pig follicle development. / Animal Science

Involuntary childlessness is a big problem around the world. One way to solve the problem is to receive oocytes or semen from a donor. In Sweden, semen donation has been regulated by law since 1985 and oocyte donation since 2003. The aim of this study was to investigate what motivations women and men in Sweden have to donate gametes, if they feel any ambivalence to donate, and to compare if there is any difference in motivation and ambivalence between women and men. Motivation was measured with eight statements based on previous results and clinical experience. Ambivalence was measured with a scale consisting of seven statements that addressed thoughts and feelings about the donation. The participants in the study were donors at some of the seven infertility clinics in Sweden. The dropout rate for the sperm donors was 19 %. For the egg donors the dropout rate was 17 %.. The main result showed that the main motivation for donating oocytes or semen was helping childless couples. The significant differences between women’s and men’s motivations for donating oocytes or semen were that the women were keener to helping others, while the men to a higher extent wanted to do something important, spread their genes and find out about their own fertility. The oocyte and semen donors did not feel any particular ambivalence about the decision to donate, most of them did not find it difficult to make the decision, and they would have been disappointed if they had not been allowed to donate for some reason. The conclusions to be drawn from this study are that once the donors have decided to donate, they don’t feel any particular ambivalence about the donation, and women and men have different motivations to why they are donating, even if the main motivation is the same. / Ofrivillig barnlöshet är ett stort problem världen över. Ett sätt att lösa problemet är att ta emot ägg eller spermier ifrån en donator. I Sverige har spermiedonation varit reglerat i lag sedan 1985 och äggdonation sedan 2003. Syftet med denna studie var att undersöka vilka motiv kvinnor och män i Sverige har till att donera ägg respektive spermier, om de känner någon ambivalens till att donera, samt att jämföra om det är någon skillnad i motiv och ambivalens mellan kvinnor och män. Motiv mättes med åtta påståenden konstruerade utifrån tidigare resultat och klinisk erfarenhet. Ambivalens mättes med en skala som bestod av sju påståenden som behandlade tankar och känslor kring donationen, Deltagarna i studien var donatorer vid någon av de sju infertilitetscentra i Sverige. Bortfallet för spermiedonatorerna var 19 %. För äggdonatorerna var bortfallet 17 %. Huvudresultatet visade att det främsta motivet hos kvinnor och män till att donera ägg respektive spermier i Sverige var att hjälpa barnlösa par. De signifikanta skillnaderna mellan kvinnors och mäns motiv till att donera ägg respektive spermier var att kvinnor var mer måna om att hjälpa andra, medan männen i högre grad ville göra något betydelsefullt, sprida sina gener och få reda på hur det stod till med den egna fertiliteteten. Ägg- och spermiedonatorerna kände ingen större ambivalens inför beslutet om att donera, de flesta tyckte inte att beslutet var svårt att ta, och de skulle ha blivit besvikna om de inte fick donera av någon anledning. Slutsatser som har dragits är att när ägg- respektive spermiedonatorer väl har bestämt sig för att donera känner de ingen större ambivalens inför donationen, och män och kvinnor har skilda motiv till varför de donerar även om huvudmotivet är detsamma.

Background: Hybridogenesis (hemiclonal inheritance) is a kind of clonal reproduction in which hybrids between parental species are reproduced by crossing with one of the parental species. European water frogs (Pelophylax esculentus complex) represent an appropriate model for studying interspecies hybridization, processes of hemiclonal inheritance and polyploidization. P. esculentus complex consists of two parental species, P. ridibundus (the lake frog) and P. lessonae (the pool frog), and their hybridogenetic hybrid - P. esculentus (the edible frog). Parental and hybrid frogs can reproduce syntopically and form hemiclonal population systems. For studying mechanisms underlying the maintenance of water frog population systems it is required to characterize the karyotypes transmitted in gametes of parental and different hybrid animals of both sexes. Results: In order to obtain an instrument for characterization of oocyte karyotypes in hybrid female frogs, we constructed cytological maps of lampbrush chromosomes from oocytes of both parental species originating in Eastern Ukraine. We further identified certain molecular components of chromosomal marker structures and mapped coilin-rich spheres and granules, chromosome associated nucleoli and special loops accumulating splicing factors. We recorded the dissimilarities between P. ridibundus and P. lessonae lampbrush chromosomes in the length of orthologous chromosomes, number and location of marker structures and interstitial (TTAGGG)(n)-repeat sites as well as activity of nucleolus organizer. Satellite repeat RrS1 was mapped in centromere regions of lampbrush chromosomes of the both species. Additionally, we discovered transcripts of RrS1 repeat in oocytes of P. ridibundus and P. lessonae. Moreover, G-rich transcripts of telomere repeat were revealed in association with terminal regions of P. ridibundus and P. lessonae lampbrush chromosomes. Conclusions: The constructed cytological maps of lampbrush chromosomes of P. ridibundus and P. lessonae provide basis to define the type of genome transmitted within individual oocytes of P. esculentus females with different ploidy and from various population systems.

In Drosophila, early embryonic development is controlled by maternally loaded RNAs and proteins. For proper development to occur it is vital these maternal transcripts are post-transcriptionally regulated. SMAUG, a major post-transcriptional regulator, has been found to be responsible for the destabilization of two thirds of the unstable maternal transcripts upon egg activation (Tadros et al., 2007). smg mRNA is translationally repressed in stage 14 oocytes, but its translation is activated upon egg activation in a PAN GU kinase dependent manner. Here I show that redundant translational repression elements reside in the smg 3’UTR, and PUMILIO mediates repression through one of these elements. I also show that these elements are sufficient to cause translational repression in stage 14 oocytes. smg mRNA appears to be regulated post-initiation in stage 14 oocytes in a large repression complex which is similar to smg mRNA repression in a png mutant.

<p><i>In vitro</i> production of embryos allows efficient management of herd genetics, reduction of disease impact, and if used in combination with other reproductive technologies it could aid in preserving the threatened genetic diversity of swine. <i>In vitro</i> maturation (IVM) is identified as a deficient step in porcine in vitro production (IVP) of embryo systems, which decreases the overall success of IVP. There are problems encountered in each step of IVP; chromosomal abnormalities and decreased cell numbers in blastocysts during <i>in vitro</i> culturing (IVC), and low monospermic fertilization rates during <i>in vitro</i> fertilization (IVF) may be a result of insufficient IVM. As an addition to maturation media, porcine follicular fluid (pFF) can affect IVM. Estrogen can be found in high concentrations in pFF; possibly contributing to the effects seen when pFF is added to IVM. The objective of this thesis was to investigate the effects of estrogen supplementation during IVM on IVP of porcine embryos.</p> <p>The first objective was to evaluate the <i>in vitro</i> maturation rates of porcine oocytes in two maturation media: protein-free and 10% pFF supplemented. Nuclear maturation of oocytes was evaluated using Lamin/Dapi staining of oocytes matured in protein-free and 10% pFF maturation media to ensure the efficiency of the protein-free media. Protein-free and 10% pFF media mature oocytes at similar rates (91% and 89% respectively).</p> <p>The transcripts within the oocyte can be altered based on the <i>in vitro</i> maturation environment, so the second objective was to observe the expression of four chosen maternal effect genes: Basonuclin-1 (<i>BNC1</i>), Nucleoplasmin 2 (<i>NPM2</i>), Zygote arrest 1 (<i>ZAR1</i>), and Tripartite-motif protein-24 (<i>TRIM24</i>), using oocytes matured in 50 ng/ml, 100 ng/ml, or 1000 ng/ml of estradiol 17-&beta; (E₂), 10% pFF, or protein-free maturation media. Expression of maternal effect genes, was shown by the &Delta;Ct (cycle threshold) values, obtained from the difference between the Ct values of the normalizing gene (<i>GAPDH</i>) and the genes of interest evaluated through QRT-PCR. Values of &Delta;Ct were analyzed in place of fold change to avoid data manipulation. The &Delta;Ct expression of <i>TRIM24</i> in 0 ng/ml E₂ maturation medium and the 10% pFF maturation medium were significantly different (p<0.05) from the non-matured control, the other maternal determinant genes did not differ in their expression under any treatment.</p> <p>We hypothesized that estradiol's effects on IVM would be evident when analyzing cleavage and blastocyst formation rates. Cleavage and blastocyst formation rates were examined following <i>in vitro</i> fertilization of oocytes matured in 100 ng/ml E₂, 10% pFF, or a protein-free maturation medium to investigate the effect of estradiol on IVP embryos. Cleavage rates for the E₂ (n= 252; 60.2%) or 10% pFF (n= 256; 55.7%) additions to the maturation media did not differ (p>0.05) when compared to the protein-free maturation media (n=264; 54.9%). Both 10% pFF and E<syb>2</sub> groups had significantly higher blastocyst formation rates (p&le;0.05) than the protein-free maturation media (n=264; 3.5%), although no statistical difference was observed between the blastocyst formation rates of the 10% pFF (n=256; 12.4%) and E2 (n=252; 14.6%) groups.</o> <p>As a final study, the global gene expression of oocytes matured in a control protein-free media and the protein-free media supplemented with 100 ng/ml E₂ or 10% pFF was investigated using microarray analysis. Genes were not differentially expressed among the matured groups with the outlined threshold values of -2 &ge; log2(fold change) &ge; 2, and adjusted p-value &le;0.05. A total of 16 differentially expressed genes between the non-matured and all matured groups exceeded this threshold. Of these genes, 6 are novel transcribed regions with evidence of being an embryonic EST, and 1 is a novel protein-coding gene. The other genes are FBJ murine osteosarcoma viral oncogene homolog (<i>FOS</i>), Vimentin (<i>VIM</i>), Capthesin C (<i>CTSC</i>), Selenium binding protein 1 (<i>SELENBP1</i>), Poly(A) binding protein cytoplasmic 1 (<i>PABPC1</i>), Tissue factor pathway inhibitor 2 (<i>TFPI2</i>), Cysteine-rich, angiogenic inducer 61 (<i>CYR61</i>), Acyl-CoA synthetase long-chain family member 6 (<i>ACSL6</i>), and Phospholipase A2 group VII (<i>PLA2G7</i>).</p> <p>In conclusion, successful nuclear maturation of oocytes derived of prepubertal gilt abbatoire derived ovaries can be achieved without pFF or hormone supplementation. The expression of maternal determinant genes is not affected in a dose dependant manner, and removal of E₂ or supplementation of pFF during maturation may alter the expression of <i>TRIM24</i> from the non-matured control; where no other maternal effect gene changes through maturation. Estradiol has a similar effect as pFF during <i>in vitro</i> maturation of porcine oocytes as seen by cleavage and blastocyst formation rates. And media does not affect the global gene expression of porcine oocytes, though there is a temporal control of gene expression through maturation.</p>

In Drosophila, early embryonic development is controlled by maternally loaded RNAs and proteins. For proper development to occur it is vital these maternal transcripts are post-transcriptionally regulated. SMAUG, a major post-transcriptional regulator, has been found to be responsible for the destabilization of two thirds of the unstable maternal transcripts upon egg activation (Tadros et al., 2007). smg mRNA is translationally repressed in stage 14 oocytes, but its translation is activated upon egg activation in a PAN GU kinase dependent manner. Here I show that redundant translational repression elements reside in the smg 3’UTR, and PUMILIO mediates repression through one of these elements. I also show that these elements are sufficient to cause translational repression in stage 14 oocytes. smg mRNA appears to be regulated post-initiation in stage 14 oocytes in a large repression complex which is similar to smg mRNA repression in a png mutant.

La polispermia (entrada de más de un espermatozoide al ovocito) es una condición patológica en mamíferos ya que impide el desarrollo embrionario. En la especie porcina, la polispermia es un problema común y aún sin resolver en los sistemas de fecundación in vitro (FIV). Los gránulos corticales (GCs) de los ovocitos de mamíferos estan implicados en el bloqueo de la polispermia, sin embargo, poco se sabe acerca de la composición y función de estas organelas. Esta ampliamente descrito que las moléculas liberadas de los GCs durante la fecundación o activación ovocitaria mediante estimulación química o eléctrica producen importantes modificaciones, particularmente en la zona pelúcida (ZP), el espacio perivitelino y, probablemente, el oolema del ovocito. Estas modificaciones repercuten directamente en el bloqueo de la polispermia. El conocimiento del contenido de los GCs y proteínas del oolema así como su papel durante la fecundación en la especie porcina es escaso. La mayoría de la información que se tiene en la actualidad se ha obtenido del modelo murino. En la presente tesis doctoral, investigamos la presencia de posibles proteínas de los GCs en ovocitos porcinos así como la presencia de metaloproteasas ADAM-10 y ADAM-17 en ovocitos porcinos y bovinos. Para ello, este estudio se dividió en tres apartados: / Polyspermy (entering of more than a spermatozoon into the oocyte) is a pathological condition in mammals since it avoids the normal embryonic development. In the pig species, Polyspermy is a common problem still unsolved in the current systems of in vitro fertilization (IVF). The cortical granules (CGs) from mammal's oocytes are involved in the block to polyspermy. However, little is known about the composition and function of these organelles. It is widely described that the molecules released of the CGs during the fertilization or oocyte activation, by means of chemical or electrical stimulation, produce important modifications, particularly in the zona pelucida (ZP), the periviteline space and, probably, oolema of the oocyte. These modifications have a direct role in the block to polyspermy. The knowledge about the content of the CGs and the oolema proteins of as well as their role during fertilization in pigs is still scarce. The majority of the information that we currently have it has been obtained from the murine model. In the present Doctoral Thesis, we investigated the presence of possible proteins of the CGs in pig oocytes as well as the presence of metaloproteases ADAM-10 and ADAM-17 in pig and bovine oocytes. For that, this study was divided into three sections

A prolonged growth phase of the ovulatory follicle results in follicular aging. Whether follicular aging is detrimental or beneficial to oocyte competence is not fully known. The objective of this thesis is to investigate the effects of follicular aging on oocyte competence and granulosa cell gene expression in cattle. Four sets of experiments were designed to address the objective. The following hypotheses were tested during the course of these studies: 1) oocyte competence will improve by the longer growing phase but will be adversely affected by FSH starvation, 2) follicles that undergo superstimulation will have different gene expression than dominant follicles from a natural cycle, 3) extending the superstimulation protocol by 3 days will allow follicles to mature better and 4) markers of maturity, cellular health and survival will be turned off by FSH starvation. The objective of the first study (Chapter 3) was to determine the effects of extending the length of superstimulation and follicular aging on oocyte competence by in vitro embryo production. Multiple follicles were allowed to grow for 4 (Short FSH) or 7 days (Long FSH) under the treatment of 8 or 14 injections of FSH (at 12-hour intervals), respectively. Multiple follicles in the FSH starvation group were allowed to grow for 7 days but FSH was provided for only the first 4 days of superstimulation. Extending the duration of follicular growth by superstimulation resulted in a greater number of ≥9 mm follicles and in 2.5 more transferable embryos per animal (morulae+blastocysts) at Day 9 of in vitro embryo culture. The FSH starvation resulted in a greater proportion of poor quality oocytes lower cleavage rate and lower embryonic development. Microarray analysis was used to assess the effect of superstimulation (Chapter 4), follicular aging (Chapter 5) and FSH starvation (Chapter 6) on the gene expression profile of superstimulated granulosa cells. Gene expression of granulosa cells from the post-LH preovulatory dominant follicle was compared (Chapter 4) with those from follicles of the same status after a standard 4-day superstimulation (same protocol as Short FSH group from Chapter 3). A total of 190 genes were down-regulated and 280 genes were upregulated in the superstimulated group when compared with the reference (non-superstimulated control). Data analysis showed that superstimulated follicles are still in a growing phase compared to untreated dominant follicles (most of the upregulated genes are related to matrix remodeling due to tissue proliferation) and did not respond to LH properly (down regulation of LH gene markers). Four-day superstimulation also disturbed genes related to angiogenesis and activated oxidative stress response genes. Extending the superstimulation protocol (7 days; same protocol as Long FSH from Chapter 3) allowed more time for follicles to leave the growing stage and properly respond to LH surge (most of the upregulated genes in the Long FSH group are markers of post LH surge) when compared to the standard 4 day superstimulation protocol (Short FSH; reference group) (Chapter 5). Moreover, the follicles from Long FSH show proximity to ovulation. The continuous FSH support during the extended superstimulation protocol is crucial for follicular health since FSH starvation disturbed genes markers of oocyte quality and embryo development (Chapter 6). Granulosa cells that underwent FSH starvation do not respond to LH surge, which could be detrimental to ovulation (Chapter 6). Therefore, follicles from Short FSH are delayed in maturation and differentiation but the oocyte competence is not compromised. Extending superstimulation protocol by 3 d enhanced the ovarian response to FSH treatment and allowed more time for follicles to mature and properly respond to the LH stimulus. A period of FSH starvation after superstimulatory treatment compromised follicular health, ability to respond to LH and ovulate, oocyte quality and the fertilization process.

<p><i>In vitro</i> production of embryos allows efficient management of herd genetics, reduction of disease impact, and if used in combination with other reproductive technologies it could aid in preserving the threatened genetic diversity of swine. <i>In vitro</i> maturation (IVM) is identified as a deficient step in porcine in vitro production (IVP) of embryo systems, which decreases the overall success of IVP. There are problems encountered in each step of IVP; chromosomal abnormalities and decreased cell numbers in blastocysts during <i>in vitro</i> culturing (IVC), and low monospermic fertilization rates during <i>in vitro</i> fertilization (IVF) may be a result of insufficient IVM. As an addition to maturation media, porcine follicular fluid (pFF) can affect IVM. Estrogen can be found in high concentrations in pFF; possibly contributing to the effects seen when pFF is added to IVM. The objective of this thesis was to investigate the effects of estrogen supplementation during IVM on IVP of porcine embryos.</p> <p>The first objective was to evaluate the <i>in vitro</i> maturation rates of porcine oocytes in two maturation media: protein-free and 10% pFF supplemented. Nuclear maturation of oocytes was evaluated using Lamin/Dapi staining of oocytes matured in protein-free and 10% pFF maturation media to ensure the efficiency of the protein-free media. Protein-free and 10% pFF media mature oocytes at similar rates (91% and 89% respectively).</p> <p>The transcripts within the oocyte can be altered based on the <i>in vitro</i> maturation environment, so the second objective was to observe the expression of four chosen maternal effect genes: Basonuclin-1 (<i>BNC1</i>), Nucleoplasmin 2 (<i>NPM2</i>), Zygote arrest 1 (<i>ZAR1</i>), and Tripartite-motif protein-24 (<i>TRIM24</i>), using oocytes matured in 50 ng/ml, 100 ng/ml, or 1000 ng/ml of estradiol 17-&beta; (E₂), 10% pFF, or protein-free maturation media. Expression of maternal effect genes, was shown by the &Delta;Ct (cycle threshold) values, obtained from the difference between the Ct values of the normalizing gene (<i>GAPDH</i>) and the genes of interest evaluated through QRT-PCR. Values of &Delta;Ct were analyzed in place of fold change to avoid data manipulation. The &Delta;Ct expression of <i>TRIM24</i> in 0 ng/ml E₂ maturation medium and the 10% pFF maturation medium were significantly different (p<0.05) from the non-matured control, the other maternal determinant genes did not differ in their expression under any treatment.</p> <p>We hypothesized that estradiol's effects on IVM would be evident when analyzing cleavage and blastocyst formation rates. Cleavage and blastocyst formation rates were examined following <i>in vitro</i> fertilization of oocytes matured in 100 ng/ml E₂, 10% pFF, or a protein-free maturation medium to investigate the effect of estradiol on IVP embryos. Cleavage rates for the E₂ (n= 252; 60.2%) or 10% pFF (n= 256; 55.7%) additions to the maturation media did not differ (p>0.05) when compared to the protein-free maturation media (n=264; 54.9%). Both 10% pFF and E<syb>2</sub> groups had significantly higher blastocyst formation rates (p&le;0.05) than the protein-free maturation media (n=264; 3.5%), although no statistical difference was observed between the blastocyst formation rates of the 10% pFF (n=256; 12.4%) and E2 (n=252; 14.6%) groups.</o> <p>As a final study, the global gene expression of oocytes matured in a control protein-free media and the protein-free media supplemented with 100 ng/ml E₂ or 10% pFF was investigated using microarray analysis. Genes were not differentially expressed among the matured groups with the outlined threshold values of -2 &ge; log2(fold change) &ge; 2, and adjusted p-value &le;0.05. A total of 16 differentially expressed genes between the non-matured and all matured groups exceeded this threshold. Of these genes, 6 are novel transcribed regions with evidence of being an embryonic EST, and 1 is a novel protein-coding gene. The other genes are FBJ murine osteosarcoma viral oncogene homolog (<i>FOS</i>), Vimentin (<i>VIM</i>), Capthesin C (<i>CTSC</i>), Selenium binding protein 1 (<i>SELENBP1</i>), Poly(A) binding protein cytoplasmic 1 (<i>PABPC1</i>), Tissue factor pathway inhibitor 2 (<i>TFPI2</i>), Cysteine-rich, angiogenic inducer 61 (<i>CYR61</i>), Acyl-CoA synthetase long-chain family member 6 (<i>ACSL6</i>), and Phospholipase A2 group VII (<i>PLA2G7</i>).</p> <p>In conclusion, successful nuclear maturation of oocytes derived of prepubertal gilt abbatoire derived ovaries can be achieved without pFF or hormone supplementation. The expression of maternal determinant genes is not affected in a dose dependant manner, and removal of E₂ or supplementation of pFF during maturation may alter the expression of <i>TRIM24</i> from the non-matured control; where no other maternal effect gene changes through maturation. Estradiol has a similar effect as pFF during <i>in vitro</i> maturation of porcine oocytes as seen by cleavage and blastocyst formation rates. And media does not affect the global gene expression of porcine oocytes, though there is a temporal control of gene expression through maturation.</p>