Effects of the Reproductive Status on Morphological Oocyte Quality and Developmental Competence of Oocytes after In Vitro Fertilization and Somatic Cell Nuclear Transfer in Cat

This study was conducted to examine the effects of the reproductive cycle of donor cat on the quality of oocytes at recovery and developmental competence of oocytes after in vitro fertilization (IVF) and somatic cell nuclear transfer (NT). Based on the presence or absence of follicles and corpora lutea, the ovarian pairs collected were classified into inactive, follicular or luteal stages. After collection of oocytes, the oocytes were classified into four grades according to the morphological condition of oocyte cytoplasm and cumulus cells. A total of 16 558 oocytes were obtained from 198 ovarian pairs. The total mean numbers of oocytes and the mean numbers of oocytes with high quality (grade I) were significantly higher in ovarian pairs at the inactive stage (111.1 and 19.0 oocytes, respectively) than in ovarian pairs at the follicular stage (67.1 and 11.4 oocytes, respectively). A significant difference in the proportions of oocytes with grade I out of the total examined oocytes was observed between the follicular and luteal stages of ovaries (14.9% vs 20.2%, p < 0.05). The proportions of IVF embryos cleaved and developed to blastocysts significantly decreased with decreased quality of oocytes at recovery, irrespective of the reproductive status of ovaries. Moreover, there were no significant differences in the proportions of cleavage and development to the blastocyst stage of IVF and NT embryos among three oestrous stages of ovaries. These results indicate that the reproductive cycle stage of donor cat ovaries has no apparent effects on the in vitro development of oocytes after IVF and NT, but the quality of oocytes at recovery influences the development of IVF embryos.     

重组人生长激素对幼麝鼠性腺发育影响的研究

本文探索了重组人生长激素（Ｒｅｃｏｍｂｉｎａｎｔｈｕｍａｎｇｒｏｗｔｈｈｏｒｍｏｎｅ，ｒｅｈＧＨ）对幼麝鼠生殖系统发育的影响。结果表明，ｒｅｈＧＨ使试验组麝鼠睾丸间质细胞和精原细胞数量明显增加，曲细精管内的初级精母细胞数量（５６７５，５８５０和１０５０个／标准口径曲细精管，Ｐ＜００１）显著增加；试验组卵巢中生长卵泡数量较多，而且有发育后期的卵泡，对照组卵巢中则没有这种卵泡。     

Evaluation of numbers of microscopic and macroscopic follicles in cattle selected for twinning

We hypothesized that the number of microscopic follicles present in the ovaries of cattle selected for twin births (Twinner) would be greater than in the ovaries of contemporary Controls. Ovaries were collected from seven Control and seven Twinner cows at slaughter. The number of Small (1 to 3.9 mm), Medium (4 to 7.9), and Large (> 8 mm) surface follicles was counted and one ovary was fixed for histological evaluation. Fifty to sixty consecutive 6-microm slices were taken from a piece of cortical tissue, approximately 1 cm x 1 cm in area, located between the surface follicles. Microscopic follicles were classified as primordial (oocyte surrounded by a single layer of squamous pregranulosa cells), primary (oocyte surrounded by a single layer of one or more cuboidal granulosa cells), secondary (oocyte surrounded by two or more layers of granulosa cells), or tertiary (oocyte surrounded by multiple layers of granulosa cells with initiation of antrum formation to < or = 1 mm in diameter). The total number of follicles was counted in 200 fields (2 mm x 2 mm) per ovary. A field containing no follicles was classified as empty. There were significantly more secondary follicles in Twinner compared with Control ovaries (12.9 vs 6.3; P < .05). Twinners also tended to have more small surface follicles (35.4 vs 49.0; P < 0.1). We conclude that ovaries of Control and Twinner cows do not differ in the number of primordial follicles or in the number of follicles activated into the growing pool; however, Twinner cows are able to maintain more growing follicles at the secondary and subsequent stages of development.     

Differential expression of bone morphogenetic protein 4-6 (BMP-4, -5, and -6) and growth differentiation factor-9 (GDF-9) during ovarian development in neonatal pigs

Growth differentiation factor-9 (GDF-9) and bone morphogenetic proteins (BMPs), comprise the largest subgroups of ligands in the TGF-β superfamily, and have been shown to be involved in follicle development in mammals. However, whether these factors are involved in folliculogenesis in pigs is still unknown. The present study was performed to determine the relationships between early folliculogenesis and the expression of GDF-9 and BMP (BMP-4, -5 and -6) mRNAs in neonatal pigs. Ovaries were removed at 5, 16, 28 and 39 days after birth to examine the follicular population (the right ovary of each animal) and to detect mRNA expression (the left ovary of each animal). Primordial follicles accounted for >80% of the ovarian follicles from 5 days until 39 days after birth. A marked increase in primary follicles and the appearance of secondary follicles were observed in the ovaries at 28 days after birth. BMP-4, -5, and -6 and GDF-9 mRNAs were expressed by ovaries at 5-, 16-, 28- and 39-day-old pigs. The peak expression of BMP-4, -5, and -6 and GDF-9 mRNAs was observed in the ovaries at 5, 39, 28 and 16 days, respectively, after birth. These data demonstrate that folliculogenesis in piglets might be controlled by the interaction with these factors. We conclude that BMPs and GDF-9 may have distinct functions in several stages of follicle development in neonatal pig ovaries.     

The endothelial nitric oxide synthase/nitric oxide system is involved in the defective quality of bovine oocytes from low mid-antral follicle count ovaries

In a previous survey concerning cows of reproductive age, we demonstrated that oocytes isolated from ovaries with <10 medium antral follicles of 2 to 6 mm in diameter (low ovaries; Lo) show less developmental competence than oocytes collected from ovaries with >10 medium antral follicles (high ovaries; Hi). The aim of the present study was to evaluate whether a defective endothelial nitric oxide synthase/nitric oxide (eNOS/NO) system and vasculature in healthy medium antral follicles is likely to reduce oocyte competence from Lo ovaries. Thus, experiments were conducted to 1) immunolocalize eNOS protein during folliculogenesis; 2) quantify eNOS protein/vasculature in the follicle wall; and 3) verify if NO donor, S-nitroso acetyl penicillamine (SNAP) administration during in vitro maturation affects developmental competence of oocytes isolated from Lo ovaries. Endothelial nitric oxide synthase protein was detected in granulosa and theca cells, as well as in blood vessels from primordial to antral follicles. Quantitative analysis indicated that in medium antral follicles from Lo ovaries, eNOS protein expression and vasculature were reduced (P < 0.05). The addition of SNAP improved blastocyst and hatching rates of oocytes from Lo ovaries, promoting a percentage similar to oocytes from Hi ovaries, and reduced the percentage of apoptotic nuclei in in vitro-produced blastocysts (P < 0.05). Results from our study suggest that in bovine ovaries with small mid antral follicle number, a defective eNOS/NO system is related to a reduced follicle vasculature and may affect oocyte quality, thus inducing a premature decline of fertility.     

Relationship between two morphological types of ovaries and their follicular microscopic population before puberty and their ensuing follicular development and ovulation rates at puberty in gilts

A population of ovarian follicles was studied in 32 gilts with two morphological types at four physiological stages. Left ovaries were serially sectioned (10 microns), and follicles (greater than .19 mm) were counted and measured by histological technique. In Exp. 1, prepuberal gilts that maintained the grape-type (GT) or other-type (OT) of ovaries at 140 and 160 d of age as determined by laparoscopy had their population of follicles studied at 165 d of age and compared with that on d 3 of the first puberal estrus in gilts that maintained the same ovarian type (GT or OT) at 140, 160 and 180 d of age. In Exp. 2, gilts that maintained the same ovarian types at 140, 160 and 180 d of age were compared at d 19 and 3 of the first and second puberal estrus, respectively. At 165 d of age, OT ovaries contained a greater number of classes 3 (.63 to 1.12 mm) and 4 (1.13 to 2.00 mm) nonatretic (less than 4 pycnotic bodies) follicles than GT (P less than .01), whereas at d 3 of the first puberal estrus, their mean number became comparable between the two ovarian types (P greater than .1) and similar to 165-d GT ovaries. At 165 d of age, atretic follicles formed 19.6% and 10.7% of the population of antral follicles in OT and GT ovaries (P less than .05) whereas at puberty 17.5% and 19.6% atresia was observed in the same two groups, respectively (P greater than .10).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of maternal environment during gestation on ovarian folliculogenesis and consequences for fertility in bovine offspring

Mammals such as cattle, swine, sheep and humans are born with a highly variable number of ovarian follicles and oocytes in the ovaries that dwindle during ageing and are never replenished. This variation in the ovarian reserve is reflected in the numbers of antral follicles in the ovaries at all ages after birth. As numbers of follicles in ovaries are determined during gestation, the role of maternal nutrition and health during gestation (at time of ovarian development in their foetuses) has been investigated as factors that may impact oogonia proliferation and thus follicle numbers post-natally. These studies have found that both nutrition and health impact numbers of follicles in their offspring. The idea that numbers of follicles and oocytes in ovaries impact fertility is a long-held belief in reproductive biology. This has recently been tested in cattle, and it has been shown that cows with a relatively high number of antral follicles in ovaries have higher pregnancy rates, shorter calving to conception intervals and fewer artificial inseminations during the breeding season compared with cows with a lower number of follicles, and similarly, heifers with many follicles had higher pregnancy rates than those with fewer follicles. Studies summarized in this review highlight the importance of the maternal environment during gestation in determining the size of the ovarian reserve in their offspring and also the contribution of the ovarian reserve to subsequent fertility in cattle.     

Localization of oestrogen receptors within various bovine ovarian cell types at different stages of the oestrous cycle

In the present study oestrogen receptor alpha(ERalpha) and oestrogen receptor beta (ERbeta) mRNA were localized in various ovarian cell types of 23 cows at different stages of the oestrous cycle. ERalpha was detected by immunohistochemistry and the localization of ERbeta mRNA was examined using in situ hybridization. The immunostaining of ERalpha was low in the ovarian follicles, tunica albuginea and surface epithelium, but high in cells of the deep stroma and superficial stroma, which indicates a functional role of ERalpha in the cells surrounding the follicles. In contrast, ERbeta mRNA scores were low to moderate in primordial and primary follicles, and increased with the development of the follicle. ERbeta mRNA scores were higher in cystic follicles than in obliterative follicles. In the corpora lutea and corpora albicantia the scores for ERbeta mRNA were moderate. Furthermore, in the corpora lutea, ERbeta mRNA levels showed cyclic variations and were low during early dioestrus. The correlation between plasma progesterone levels and the score for ER was low and negative in all ovarian cell types. This study demonstrates the predominant role of ERbeta over ERalpha in bovine ovarian structures. Furthermore, the colocalization of both ERbeta mRNA and ERalpha in most cell types suggests possible interactions between both ER subtypes.     

Ultrastructural Aspects of the Prenatal Bovine Ovary Differentiation with a Special Focus on the Interstitial Cells

The aim of this investigation was to study the ultrastructural features during the development of fetal bovine ovaries (crown rump length ranging from 11.4 to 94.0 cm). An interesting observation was the occurrence of big elongated cells containing a variety of electron dense granules and light homogenous vacuoles/bodies. They were located between the stroma cells surrounding the germ cell cord ends, adjacent to the first formed primordial follicles, typically situated near blood vessels. ER alpha and ER beta receptor positive cells could be detected in the same regions by means of immunohistochemistry. Intercellular bridges linked the germ cells nests oogonia. Germ cell cords consisted of centrally located, large, pale oogonia, surrounded by elongated somatic cells with very long cytoplasm extensions. Primordial follicles with flat pale follicular cells could be observed on the inner end of the cords. Extrusions of the outer nuclear membrane could often been recognised in voluminous oocytes.     

Follicular progesterone levels decrease during the period of seasonal infertility in sows

Impaired reproductive performance exhibited by the domestic sow during the late summer and early autumn months is referred to as seasonal infertility. This study was carried out to determine whether there are changes in ovarian morphology and follicular steroidogenesis associated with season, which may be associated with seasonal infertility. Ovaries were collected in pairs from sows sourced from two farms and slaughtered 4 days after weaning during winter and summer. The mean progesterone concentration in follicular fluid (FF) collected from small follicles was lower in summer (701.3 ± 115.54 nm) compared with winter (1235.55 ± 164.47 nm; p<0.001). The mean progesterone concentration in the FF of large follicles was also lower in summer (1469.2 ± 156.51 nm) compared with winter (2470.9 ± 169.13 nm; p<0.001). The number of large surface antral follicles (5-8 mm in diameter) on the ovaries recovered from Farm A sows was higher during summer (17.76 ± 0.56) than in winter (15.38 ± 0.54; p<0.05). Similarly, the number of small follicles (3-4 mm in diameter) on Farm A sow ovaries was higher in summer (8.46 ± 0.66) than in winter (4.63 ± 0.53; p<0.001). In contrast, the number of small follicles on the surface of ovaries recovered from Farm B sows was higher during winter (10.17 ± 1.50) than in summer (6.45 ± 1.00; p<0.01). The number of pre-ovulatory follicles (>8 mm in diameter) was also higher in winter (1.23 ± 1.68) when compared to summer (0.51 ± 0.3; p<0.001) on the ovaries of sows from Farm B. The results suggest that there are seasonal differences in follicular steroidogenesis and ovarian dynamics. These findings add support to the theory that altered follicular steroidogenesis and ovarian morphology may possibly be the mechanism behind reduced reproductive performance during the period of seasonal infertility in sows.     

Cellular Localization of Inhibin alpha-subunit, PKB/Akt and FoxO3a proteins in the ovaries of minipigs

Experiments were conducted to examine the cellular localization of inhibin alpha-subunit, protein kinase B (PKB/Akt), and FoxO3a proteins in the ovaries of minipigs, Chinese Xiang pigs, by immunohistochemistry. The results indicated that inhibin alpha-subunits were localized in the granulosa cells of follicles at all stages but were not localized in corpora lutea. PKB was localized in the granulosa cells of primordial follicles and in the basal layers of the granulosa cells of preantral and antral follicles, but were not localized in atretic follicles and corpora lutea. FoxO3a was localized in the granulosa cells of follicles at all stages and was extensively localized in the cytoplasma of the luteinized granulosa cells of corpora lutea. Together, the stage- and cell-specific expression patterns of inhibin alpha-subunit, FoxO3a, and PKB suggest that these proteins might play potential roles in follicular development, atresia, and luteinization in the minipig.     

Messenger ribonucleic acid expressions of hepatocyte growth factor, angiopoietins and their receptors during follicular development in gilts

Angiogenic factors are associated with angiogenesis during follicular development in the mammalian ovary. The aim of the present study was to determine the relationships between the vascular network and mRNA expressions of angiopoietins (Ang)-1, Ang-2 and hepatocyte growth factor (HGF), and their receptors in follicles at different developmental stages during follicular development. Ovaries in gilts were collected 72 h after equine chorionic gonadotropin (eCG, 1250 IU) treatment for histological observation of the capillary network. Granulosa cells and thecal tissues in small (<4 mm), medium (4-5 mm) or large (>5 mm) individual follicles were collected for detection of mRNA expression of HGF, Ang-1 and Ang-2 in granulosa cells, and HGF receptor (HGF-R) and Tie-2 in the theca cells by semi-quantitative RT-PCR. The number of capillaries in the thecal cell layer increased significantly in healthy follicles at all developmental stages in the eCG group compared with those in controls. The expression of Ang-1 mRNA declined in granulosa cells of medium and large follicles and the level of Ang-2 mRNA increased in granulosa cells of small follicles after eCG treatment. The ratio of Ang-2/Ang-1 increased in small, medium and large follicles from ovaries after eCG treatment, but Tie-2 mRNA expression in the theca cells did not change. The level of HGF mRNA increased in granulosa cells of small follicles after eCG treatment but HGF-R in theca cells was not increased by eCG. These data suggested that the angiopoietins might be associated with thecal angiogenesis during follicular development in eCG-treated gilts.     

Cell-specific Distribution of Oestrogen Receptor-alpha in the Bovine Ovary

In this study, the expression of estrogen receptor alpha (ERα) in the bovine ovary is described. ERα was visualized by immunohistochemistry on paraffin sections of ovaries obtained from 11 non‐pregnant and 2 pregnant animals. In general, ERα was not observed in cells of primordial, primary and secondary follicles, whereas weak expression was noticed in cells of healthy and arteric tertiary follicles. In corpora lutea cells the expression of ERα was obvious. Intermediate to high ERα expression was present in thecal cells and in cells of the superficial and deep stroma, tunica albuginea and surface epithelium. Furthermore, the expression of ERα in stroma and tunica albuginea cells was in general, highest in cows with the lowest plasma progesterone levels, and lowest in cows with the highest plasma progesterone levels. Remarkably, the ERα expression in pregnant cows was in general, lower than in non‐pregnant cows with similar plasma progesterone levels. The relatively high expression of ERα in thecal and stromal cells in comparison with that in follicle cells suggests an indirect effect of estrogen on the follicular development. However, the exact function of ERα in the bovine ovary together with the cycle‐dependent variations in ERα expression remain to be elucidated.     

Ovarian morphology and follicular systems in yaks of different ages

Forty-five female yaks of different ages with known reproductive histories were used to determine the morphology and follicular systems of their ovaries. The histological structure of the ovaries in each age group was found to be similar and resembled that of cattle and buffalo. The atresia of primordial follicles took one form (oocyte atresia); that of growing follicles could be divided into two stages (early and late); and that of Graafian follicular were classified as early, definite and late stage. The details of the several types of atresia are described herein. The average total numbers of primordial follicles per ovary pair in 1-month-old calves, 1-year-old heifers, 2-year-old heifers and 7-10-year-old cows were 53,500 +/- 6300, 32,870 +/- 4500, 22,850 +/- 2800 and 9500 +/- 1200, respectively; those of growing follicles were 210 +/- 76, 815 +/- 95, 895 +/- 142 and 445 +/- 88, respectively; and those of Graafian follicles were 36.5 +/- 14.2, 41.7 +/- 12.3, 37.8 +/- 9.8 and 42.5 +/- 14.5, respectively. The percentage of atretic primordial follicles per ovary pair in 1-month-old calves, 1-year-old heifers, 2-year-old heifers and 7 to 10 year-old cows were 51.6, 55.5, 56.7 and 47.4%, respectively. The average total numbers of atretic growing follicles per ovary pair were 119.5 +/- 21.5, 605.5 +/- 74.3, 721.6 +/- 78.5 and 275.8 +/- 66.3, respectively; those of atretic Graafian follicles were 22.1 +/- 5.6, 21.2 +/- 7.6, 21.5 +/- 4.7 and 25.3 +/- 6.7, respectively.     

牛性机能发育阶段与卵泡、黄体因素对卵母细胞

利用屠宰母牛卵巢,对来自不同性机能发育阶段母牛的卵巢卵母细胞、不同状态卵巢卵泡的卵母细胞的体外成熟（ＩＶＭ）、体外受精（ＩＶＦ）进行了系列研究。结果表明,来自初情期、性成熟母牛卵巢的卵母细胞受精后的卵裂率（７４．７％和８１．５％）、囊胚率（２３．０％和２６．８％）显著高于来自初情期前母牛卵巢卵母细胞的卵裂率（１８．８％）和囊胚率（１．８％）Ｐ〈０．０５;有黄体卵巢的卵母细胞体外受精后的发育能力显著     

Effect of growth differentiation factor‐9 (GDF‐9) on the progression of buffalo follicles in vitrified–warmed ovarian tissues

To improve the reproductive performance of water buffalo to level can satisfy our needs, the mechanisms controlling ovarian follicular growth and development should be thoroughly investigated. Therefore, in this study, the expressions of growth differentiation factor‐9 (GDF‐9) in buffalo ovaries were examined by immunohistochemistry, and the effects of GDF‐9 treatment on follicle progression were investigated using a buffalo ovary organ culture system. Frozen–thawed buffalo ovarian follicles within slices of ovarian cortical tissue were cultured for 14 days in the presence or absence of GDF‐9. After culture, ovarian slices were fixed, sectioned and stained. The follicles were morphologically analysed and counted. Expression pattern of GDF‐9 was detected in oocytes from primordial follicles onwards, besides, also presented in granulosa cells. Moreover, GDF‐9 was detected in mural granulosa cells and theca cells of pre‐antral follicles. In antral follicles, cumulus cells and theca cells displayed positive expression of GDF‐9. In corpora lutea, GDF‐9 was expressed in both granulosa and theca lutein cells. After in vitro culture, there was no difference in the number of primordial follicles between cultured plus GDF‐9 and cultured control that indicated the GDF‐9 treatment has no effect on the primordial to primary follicle transition. GDF‐9 treatment caused a significant decrease in the number of primary and secondary follicles compared with controls accompanied with a significant increase in pre‐antral and antral follicles. These results suggest that a larger number of primary and secondary follicles were stimulated to progress to later developmental stages when treated with GDF‐9. Vitrification/warming of buffalo ovarian tissue had a little remarkable effect, in contrast to culturing for 14 days, on the expression of GDF‐9. In conclusion, treatment with GDF‐9 was found to promote progression of primary follicle that could provide an alternative approach to stimulate early follicle development and to improve therapies for the most common infertility problem in buffaloes (ovarian inactivity).     

A morphological and immunohistochemical study of healthy and atretic follicles in the ovary of the sexually immature ostrich (Struthio camelus)

The morphology of healthy and atretic follicles in the ovary of the sexually immature ostrich was described in the present study. In addition, the distribution of the intermediate filaments desmin, vimentin and smooth muscle actin, in these ovarian follicles, was demonstrated. Healthy and atretic primordial, pre-vitellogenic and vitellogenic follicles were present in the ovaries of the sexually immature ostrich. Atresia occurred during all stages of follicular development. Atretic primordial and pre-vitellogenic follicles were characterized by the presence of a shrunken oocyte surrounded by a multilayered granulosa cell layer. Two forms of atresia (types 1 and 2) were identified in vitellogenic follicles. In the advanced stages of type 1 atresia the follicle was dominated by a hyalinized mass. In contrast, in type 2 atresia the granulosa and theca interna cells differentiated into interstitial gland cells. Positive immunostaining for desmin was observed in the granulosa cells of only healthy primordial and pre-vitellogenic follicles. Atretic primordial and pre-vitellogenic follicles were immunonegative for desmin. Vimentin immunoreactivity was demonstrated in the granulosa cells of all follicles except the vitellogenic atretic follicles. The results of the present study indicate that ovarian follicles in the sexually immature ostrich undergo a cycle of growth and regression, which is similar to that reported in other avian species. Furthermore, based on the results of the immunohistochemical study, it would appear that the distribution and immunostaining of intermediate filaments changes during follicular development and atresia.     

In utero exposure to the anti-androgen flutamide influences connexin 43 and β-catenin expression in porcine fetal gonads

Recent reports have indicated a role of cell-to-cell interactions during gonadal development and functions. Numerous reports indicate that fetal hormonal disruption induces abnormalities in the developing reproductive system and, therefore, may interfere with reproductive functions later in adult life. Hence, this study investigated the effect of androgen deficiency during late prenatal periods on the gap junction-associated connexin 43 (Cx43) and the adherens junction-associated β-catenin expression in the fetal porcine gonads. Thus, pregnant gilts were injected with anti-androgen flutamide (for 7 d, 50 mg/kg BW per day) or corn oil (control groups) starting at 83 (GD90) or 101 (GD108) gestational day. On GD90 and GD108 the fetuses were excised and fetal gonads were obtained. To assess Cx43 and β-catenin expression real-time PCR and immunohistochemistry were performed. In fetal testes, Cx43 was localized between Leydig cells, whereas β-catenin was observed mainly within the seminiferous tubules. In fetal ovaries, Cx43 was detected between interstitial cells and between granulosa cells of forming follicles, whereas β-catenin was found within egg nests, in oocytes' membrane, and in granulosa cells of forming follicles. Immunohistochemistry showed decreased Cx43 and β-catenin expression in fetal gonads from flutamide-treated pigs compared with respective controls. However, the ovaries from animals treated with flutamide on GD108 showed increased Cx43 expression. The changes of Cx43 and β-catenin expression after prenatal flutamide treatment were confirmed at the mRNA level. These findings suggest that androgen deficiency during late gestation may lead to disturbed intercellular interactions in fetal porcine testes affecting testicular functions, as well as impaired follicular formation in fetal ovaries. Our results further signify the role of androgens in the regulation of cell-to-cell interactions within fetal porcine gonads.     

共培养系统的体细胞类型和状态对猪胚胎早期发育的影响

经体外成熟、受精和培养获得猪胚胎 ,采用体细胞共培养研究了体细胞类型和状态对胚胎早期发育的影响。取体外成熟的不同直径卵泡 (>5 m m,2～ 5 mm)卵母细胞的卵丘团 (颗粒细胞团 ) ,培养铺层后与猪受精卵共培养 ,组间受精卵的卵裂率和发育能力无显著差异 ;根据卵巢的状况对猪输卵管上皮细胞 (POECs)的状态进行分组 ,受精卵和卵巢表面布满卵泡的 POECs共培养 ,卵裂率显著低于卵巢表面有黄体和 /或红体的 POECs共培养组 (P<0 .0 5 ) ,虽然各组间 3～ 4-细胞的发育率无显著差异 ,但卵巢表面有红体和卵泡的 POECs共培养组的 >4-细胞的发育率显著高于卵巢表面布满卵泡的 POECs共培养组 (P<0 .0 5 ) ;受精卵在共培养系统和非共培养系统中的卵裂率无显著差异 ,受精卵非共培养系统中 3～ 4-细胞的发育能力显著低于颗粒细胞共培养组 (P<0 .0 5 ) ,极显著低于 POECs共培养组 (P<0 .0 1) ,无能力突破 4-细胞继续发育 ,与颗粒细胞单层、POECs单层共培养的受精卵 >4-细胞的发育率分别为 2 4.0 %、5 3.8% ,差异显著 (P<0 .0 5 )。结果表明 ,共培养系统对胚胎体外发育的作用 ,一方面与体细胞类型有关 ,另一方面也受输卵管上皮细胞状态的影响