Non-destructive detection of maize silage quality is essential. The aim is to propose a fast and non-destructive silage pH detection method based on a colorimetric sensor array (CSA). Extended color components, a novel sensitive dye screening method, and a feature screening method were integrated and applied to enhance pH detection. Fifty color components were constructed from five color spaces and used to extract information about the response of CSA to silage. Forward and backward stepwise selection and support vector regression (SVR) were combined to create a sensitive dye screening method, which was used to determine the optimal sensitive dye. The variable combination population analysis–iteratively retains informative variables algorithm was iterated to optimize effective features. Consequently, six hundred variables were extracted from the twelve dyes, which were able to comprehensively and finely characterize the CSA response. Four sensitive dyes were screened out from the twelve dyes, which were sensitive to silage volatile compounds and accurately reflected the odor changes. Twenty-eight effective features were preferred, based on which the SVR model had Rp2, RMSEP and RPD scores of 0.9533, 0.4186, and 4.4186, respectively; the pH prediction performance was substantially improved. This study provides technical support for the scientific evaluation of silage quality.

Rapid and scientific evaluation of silage quality is essential for livestock farming. The aim is fast, large-scale, and non-destructive detection of silage pH and quality grades. The Slime Mould Algorithm (SMA) was integrated with a cascade ensemble (cascading) to create an intelligent and adaptive modeling algorithm (SMA-configured cascading). Firstly, visible-near-infrared spectra of aerobically deteriorated silage were collected and preprocessed. Secondly, SMA was employed to mine spectral features. Finally, SMA-configured cascading was applied for adaptive modeling by configuring the learners. The results demonstrated that 39 features extracted by SMA performed optimally regarding predictive effectiveness compared to two benchmark algorithms. These features effectively captured key quality information whereas avoiding interference. The SMA-configured cascading achieved the best prediction accuracy for silage quality, outperforming conventional adaptive-based and single-learner-based modeling methods. For pH prediction, the R2p, RMSEP, MAEP, MAPEP, RPD, configuration time (ETcon), and prediction time (ETpre) of the prediction set were 0.9954, 0.1020, 0.0750, 1.6836 %, 14.9808, 19070 s, and 20.98 s, respectively. The optimal cascading configuration was Partial Least Squares Regression (PLSR), PLSR, support vector machine (SVM), and SVM. For quality grade determination, the Accuracyp, F1scorep, ETcon, and ETpre of the prediction set were 86.11 %, 0.8639, 3097.47 s, and 21.49 s, respectively, with the configured cascading being adaptive boosting and K-nearest neighbor. The proposed method enables efficient and adaptive modeling based on spectral features, optimizing quality prediction. It holds the potential for in-situ detection through offline configuration and online prediction. This study provides theoretical and technical support for the rapid assessment of silage quality in production environments.

We studied the effect of fibroblast growth factor receptor 3 (FGFR3) inhibitor BGJ-398 on the differentiation of bone marrow mesenchymal stem cells (BM MSC) into osteoblasts in wild type (wt) mice and in animals with mutation in TBXT gene (mt) and possible differences in the pluripotency of these cells. Cytology tests showed that the cultured BM MSC could differentiate into osteoblasts and adipocytes. The effect of different BGJ-398 concentrations on the expression of FGFR3, RUNX2, SMAD1, SMAD4, SMAD5, SMAD6, SMAD7, and SMAD8 were studied by quantitative reverse transcription PCR. The expression of RUNX2 protein was evaluated by Western blotting. BM MSC of mt and wt mice did not differ in pluripotency and expressed the same membrane marker antigens. BGJ-398 inhibitor reduced the expression of FGFR3 and RUNX2. In BM MSC from mt and wt mice have similar gene expression (and its changing) in FGFR3, RUNX2, SMAD1, SMAD4, SMAD5, SMAD6, SMAD7, and SMAD8 genes. Thus, our experiments confirmed the effect of decreased expression of FGFR3 on osteogenic differentiation of BM MSC from wt and mt mice. However, BM MSC from mt and wt mice did not differ in pluripotency and are an adequate model for laboratory research.

OBJECTIVE: The incidence of thyroid cancer is rising globally. Most patients progress slowly, but some patients develop lymph node and distant metastasis earlier, and their prognosis is poor. Therefore, early diagnosis and warning of malignancy are very meaningful for such patients. SAS1B gene is a newly discovered protein expressed on the surface of mature egg cells and has metalloendopeptidase activity. We aimed at exploring whether SAS1B is involved in the occurrence of thyroid cancer, and at providing evidence for early diagnosis and targeted therapy of thyroid cancer. PATIENTS AND METHODS: In this study, a rabbit anti-human SAS1B polyclonal antibody was prepared by gene recombination technology. The indirect ELISA method was used to detect the SAS1B protein expression in the serum of 69 patients with thyroid cancer and 55 normal controls, and the relevant pathological factors were analyzed. Immunohistochemistry and PCR technology were used to investigate the expression levels of SAS1B protein and mRNA in 30 thyroid cancer tissues and 23 control thyroid tissues. RESULTS: The titer of SAS1B recombinant antibody was 1:51200. The expression of SAS1B in the serum of patients with thyroid cancer was higher than that in the normal control group (p<0.01). The antibody had a good sensitivity in serum detection of cancer patients (p=0.008<0.01), the linear regression analysis result was that the expression of SAS1B gene was related to tumor envelope invasion and lymph node metastasis (p=0.003<0.01, p=0.003<0.01), and it was irrelevant to the patient’s gender, age, tumor mass size, number of cancer foci, pathological stage, etc. (p>0.05). The results of immunohistochemistry showed that SAS1B protein was mainly located in the cytoplasm and membrane of thyroid cancer cells. The expression intensity in thyroid cancer tissues was higher than that in control tissues (p<0.05), but it was not expressed in normal thyroid tissues. Antibodies showed a good sensitivity that was used to detect thyroid cancer tissues (p=0.000<0.01). The results of ordinary PCR detection using thyroid cancer tissue and control thyroid tissue showed that the amplification products of the three domains (N-terminal, C-terminal and catalytic domain) of the SAS1B gene showed high expression in thyroid cancer tissue. q-PCR results showed that the expression of SAS1B gene in thyroid cancer and control thyroid tissue was higher than that in control group (p<0.05), and the genes of Aurora A and BARD1 related to centrosome replication and DNA replication forks protection during the proliferation were highly expressed in thyroid cancer tissue. The study results suggested that SAS1B was involved in the carcinogenesis of thyroid cancer. The Hum_mPLoc.2.0 software, PSORT Ⅱ software and UniProt software were used to predict that SAS1B protein had secretory protein properties. CONCLUSIONS: The above data indicate that the SAS1B gene is closely related to the process of thyroid cancer and can serve as a good tumor marker that can be used for early diagnosis and early warning of thyroid malignancy.

Fast and non-destructive estimation of canopy chlorophyll content from hyperspectral sensing is essential to monitor the physiological status of vegetation or to estimate crop above ground nitrogen status. The objective of this study is to propose an optimal method for the relative chlorophyll content (SPAD) estimation of sugar beet canopy using ground-based hyperspectral imagery. Field experiments were conducted over three years at three different growth stages, across three different sites, using different cultivars and nitrogen (N) application rates. Quantitative correlations between SPAD value and canopy hyperspectral reflectance of sugar beet canopy after different pretreatment algorithms were established. Ten classical spectral indexes selected from the literature for estimating SPAD value in sugar beet canopy were evaluated and compared to a novel modified chlorophyll index (MCI) produced in this study by introducing a parameter to chlorophyll index (CI) to improve the estimation accuracy. Normalized difference vegetation index (NDVI) and chlorophyll index (CI) were optimized by using all possible combinations of spectral bands from the range of 390 nm to 990 nm. The prediction performance of partial least squares (PLS) regression models for optimized indexes (e.g., NDVI, CI and MCI), compared to the corresponding classical spectral indexes (e.g., ND550, ND705, CIgreen and CIred edge) was examined. Results showed that standard normal variate transformation (SNV) was the best pretreatment method for the hyperspectral data of this study. Models resulted after bands combinations optimization were found to be more accurate than models developed using the classical spectral indexes. The performance of proposed spectral index, MCI (R747, R839), MCI (R861, R884) and MCI (R931, R770), were best for the prediction accuracy of SPAD value in sugar beet for the validation set with the coefficient of determination (R2) of 0.83, 0.70 and 0.75, the root mean square error (RMSE) of 2.37, 3.11 and 2.78, and the relative root mean square error (RRMSE) of 4.95%, 6.05% and 5.75%, for the rapid growth stage of leaf cluster, sugar growth stage and sugar accumulation stage, respectively. It can be concluded that the index proposed can be implemented for the prediction of SPAD value of sugar beet using proximal hyperspectral sensors under a wide range of environmental conditions.

Timely diagnosis of sugar beet above-ground biomass (AGB) is critical for the prediction of yield and optimal precision crop management. This study established an optimal quantitative prediction model of AGB of sugar beet by using hyperspectral data. Three experiment campaigns in 2014, 2015 and 2018 were conducted to collect ground-based hyperspectral data at three different growth stages, across different sites, for different cultivars and nitrogen (N) application rates. A competitive adaptive reweighted sampling (CARS) algorithm was applied to select the most sensitive wavelengths to AGB. This was followed by developing a novel modified differential evolution grey wolf optimization algorithm (MDE–GWO) by introducing differential evolution algorithm (DE) and dynamic non-linear convergence factor to grey wolf optimization algorithm (GWO) to optimize the parameters c and γ of a support vector machine (SVM) model for the prediction of AGB. The prediction performance of SVM models under the three GWO, DE–GWO and MDE–GWO optimization methods for CARS selected wavelengths and whole spectral data was examined. Results showed that CARS resulted in a huge wavelength reduction of 97.4% for the rapid growth stage of leaf cluster, 97.2% for the sugar growth stage and 97.4% for the sugar accumulation stage. Models resulted after CARS wavelength selection were found to be more accurate than models developed using the entire spectral data. The best prediction accuracy was achieved after the MDE–GWO optimization of SVM model parameters for the prediction of AGB in sugar beet, independent of growing stage, years, sites and cultivars. The best coefficient of determination (R2), root mean square error (RMSE) and residual prediction deviation (RPD) ranged, respectively, from 0.74 to 0.80, 46.17 to 65.68 g/m2 and 1.42 to 1.97 for the rapid growth stage of leaf cluster, 0.78 to 0.80, 30.16 to 37.03 g/m2 and 1.69 to 2.03 for the sugar growth stage, and 0.69 to 0.74, 40.17 to 104.08 g/m2 and 1.61 to 1.95 for the sugar accumulation stage. It can be concluded that the methodology proposed can be implemented for the prediction of AGB of sugar beet using proximal hyperspectral sensors under a wide range of environmental conditions.

In order to reduce the power consumption of the round baler and improve the quality of the bale, the compression and relaxation characteristics of alfalfa were investigated with respect to moisture content, feeding speed, and steel roll speed. Experimental trials were performed by using a steel-roll fixed chamber round baler rotary compression test platform. Three moisture contents were prepared, 18%, 21%, and 24%. The feeding speeds were set at 1.11 m·s-1, 1.39 m·s-1, and 1.67 m·s-1, and the steel roll speeds were 106 r·min-1, 126 r·min-1, and 146r·min-1, respectively. The experimental data for these trails were collected and three compression models and a generalized Maxwell model were fitted to the pressure, density, or time data. The maximum compression pressure decreased with the increase of moisture content and increased with the increase of feeding speed, while the steel roll speed had no significant effect on the maximum compression pressure. The stress relaxation time decreased with the increase of moisture content, feeding speed and steel roll speed. The equilibrium stress decreased with the increase of the steel roll speed and moisture content and increased with the increase of the feeding speed. All compression models had a good fit for the experimental data.

STUDY QUESTIONCan bovine oocyte antioxidant defence and oocyte quality be improved by extending the duration of pre-in vitro maturation (IVM) with cyclic adenosine mono-phosphate (cAMP) modulators?SUMMARY ANSWERLengthening the duration of cAMP-modulated pre-IVM elevates intra-oocyte reduced glutathione (GSH) content and reduces hydrogen peroxide (H2O2) via increased cumulus cell-oocyte gap-junctional communication (GJC), associated with an improvement in subsequent embryo development and quality.WHAT IS KNOWN ALREADYOocytes are susceptible to oxidative stress and the oocyte's most important antioxidant glutathione is supplied, at least in part, by cumulus cells. A temporary inhibition of spontaneous meiotic resumption in oocytes can be achieved by preventing a fall in cAMP, and cyclic AMP-modulated pre-IVM maintains cumulus-oocyte GJC and improves subsequent embryo development.STUDY DESIGN, SIZE, DURATIONThis study consisted of a series of 10 experiments using bovine oocytes in vitro, each with multiple replicates. A range of pre-IVM durations were examined as the key study treatments which were compared with a control. The study was designed to examine if one of the oocyte's major antioxidant defences can be enhanced by pre-IVM with cAMP modulators, and to examine the contribution of cumulus-oocyte GJC on these processes.PARTICIPANTS/MATERIALS, SETTING, METHODSImmature bovine cumulus-oocyte complexes were treated in vitro without (control) or with the cAMP modulators; 100 µM forskolin (FSK) and 500 µM 3-isobutyl-1-methyxanthine (IBMX), for 0, 2, 4 or 6 h (pre-IVM phase) prior to IVM. Oocyte developmental competence was assessed by embryo development and quality post-IVM/IVF. Cumulus-oocyte GJC, intra-oocyte GSH and H2O2 were quantified at various time points during pre-IVM and IVM, in the presence and the absence of functional inhibitors: carbenoxolone (CBX) to block GJC and buthionine sulfoximide (BSO) to inhibit glutathione synthesis.MAIN RESULTS AND THE ROLE OF CHANCEPre-IVM with FSK + IBMX increased subsequent blastocyst formation rate and quality compared with standard IVM (P < 0.05), regardless of pre-IVM duration. The final blastocyst yields (proportion of blastocysts/immature oocyte) were 26.3% for the control, compared with 39.2, 35.2 and 34.2%, for the 2, 4 and 6 h pre-IVM FSK + IBMX treatments, respectively. In contrast to standard IVM (control), pre-IVM with cAMP modulators maintained open gap junctions between cumulus cells and oocytes for the duration (6 h) of pre-IVM examined, and persisted for a further 8 h in the IVM phase. Cyclic AMP-modulated pre-IVM increased intra-oocyte GSH levels at the completion of both pre-IVM and IVM, in a pre-IVM duration-dependent manner (P < 0.05), which was ablated when GJC was blocked using CBX (P < 0.05). By 4 h of pre-IVM treatment with cAMP modulators, oocyte H2O2 levels were reduced compared the control (P < 0.05), although this beneficial effect was lost when oocytes were co-treated with BSO. Inhibiting glutathione synthesis with BSO during pre-IVM ablated any positive benefits of cAMP-mediated pre-IVM on oocyte developmental competence (P < 0.01).LIMITATIONS, REASONS FOR CAUTIONIt is unclear if the improvement in oocyte antioxidant defence and developmental competence reported here is due to direct transfer of total and/or reduced glutathione from cumulus cells to the oocyte via gap junctions, or whether a GSH synthesis signal and/or amino acid substrates are supplied to the oocyte via gap junctions. Embryo transfer experiments are required to determine if the cAMP-mediated improvement in blastocyst rates leads to improved live birth rates.WIDER IMPLICATIONS OF THE FINDINGSIVM offers significant benefits to infertile and cancer patients and has the potential to significantly alter ART practice, if IVM efficiency in embryo production could be improved closer to that of conventional IVF (using ovarian hyperstimulation). Pre-IVM with cAMP modulators is a simple and reliable means to improve IVM outcomes.STUDY FUNDING/COMPETING INTERESTSThis work was supported by grants and fellowships from the National Health and Medical Research Council of Australia (1007551, 627007, 1008137, 1023210) and by scholarships from the Chinese Scholarship Council (CSC) awarded to H.J.L. and the Japanese Society for the Promotion of Science Postdoctoral Fellowship for Research Abroad awarded to S.S. The Fluoview FV10i confocal microscope was purchased as part of the Sensing Technologies for Advanced Reproductive Research (STARR) facility, funded by the South Australian Premier's Science and Research Fund. We acknowledge partial support from the Australian Research Council Centre of Excellence for Nanoscale BioPhotonics (CE140100003). We declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Searchable abstracts of presentations at key conferences on reproductive biology and medicine ISSN 2052-1472 (online)

Effective heat transfer is important for increasing efficiency of magnetic refrigeration.In this paper,we report on the establishment of heat transfer model based on an improved Navier-Stokes equation for the AMR cycle reciprocating magnetic refrigerator,and simulate the magnetic refrigeration cycle of Gadolinium using numerical simulation method.The theoretical and numerical results show that the change of the heat transfer parameters can impact on cooling effect.When the porosity ranged from 0.15 to 0.4,the smaller value makes the better cooling capacity.And the cycle frequency ranged from 0.21 Hz to 0.42 Hz,the higher frequency leads to higher cooling capacity.When the fluid velocity ranged from 0.2m/s to 0.4m/s,the faster velocity can make the higher cooling capacity.

In this article,we investigated the preparation of amorphous Fe91-xLaxZr9(x=1,3,5,10) alloys and their magnetic and magnetocaloric properties.The samples of the amorphous alloys were prepared by using arc melting and melt spinning methods.X-ray diffraction shows that the samples form in amorphous state.The isothermal magnetic entropy change of Fe81La10Zr9 alloy was determined from magnetization data basis on Maxwell relation.The result shows that the maximal magnetic entropy change is 0.8 J/(kg·K).The half-peak wide temperature span is from 245 K to 285 K.

The factor associated suicide (Fas) and its ligand (FasL) signaling is an important regulatory pathway of apoptosis in mammalian follicles. However, whether apoptosis in bovine oocytes is regulated by the Fas-FasL signaling pathway remains unknown. In this study, localization of Fas and FasL in immature oocytes and FasL in cumulus cells were examined using immunofluorescence staining. In addition, exogenous FasL was added to an in vitro culture system to investigate apoptotic changes in bovine oocytes, using annexin-V and terminal uridine nick-end labeling staining, and real-time quantitative polymerase chain reaction. In this study, Fas was expressed in immature oocytes, whereas FasL was expressed in cumulus cells, but not in immature oocytes; annexin-V- and terminal uridine nick-end labeling-positive rates of oocytes treated with 2, 10, or 50 ng/mL FasL were higher than those of control oocytes (P < 0.05); and oocytes from the three treatment groups had higher expression levels of Fas and B cell lymphoma/leukemia-2 associated X than those in the control group (P < 0.05). Taken together, we concluded that the Fas-FasL signaling pathway was involved in regulation of bovine oocyte apoptosis, perhaps related to B cell lymphoma/leukemia-2 associated X upregulation. (C) 2013 Elsevier Inc. All rights reserved.

采用两步溶胶-凝胶法制备了单分散、球形、亚微米级、壳层厚度可调的核-壳结构SiO2@α-Fe2O3亚微米球.借助X-射线衍射仪(XRD)、扫描电子显微镜(SEM)和紫外可见光谱仪(UVS)对结果样品的纯度、结构、形貌、尺寸和光催化性能进行了表征,探讨了样品的形成机理和光催化机理.实验结果表明,制备的样品由亚微米级(平均粒径400 nm) SiO2核和粒径约为30 nm的壳通过羟基键合作用连接而成,并显示出很强的光催化性能.

采用电弧熔炼和真空电磁感应甩带方法制备了Fe91-xLaxZr9（x=1,3,5,10）系列非晶合金,研究了该非晶合金的磁性和磁热效应.X-射线衍射结果显示,样品的形成主要为非晶态合金.非晶态Fe81La10Zr9合金的磁熵变随温度变化的曲线表明,外场为1.5T时样品最大等温磁熵变为0.8J/（kg.K）,半峰宽对应的温度变化范围为245～285K.

A series of La10Fe81-xZr9Bx(x=0,1,2) alloys were prepared by arc melting method under Ar atmosphere.Then,the alloys were rapidly cooled by melt-spinning method using the electromagnetic induction furnace.X-ray diffraction results show that the alloys are in amorphous state.The magnetic measurements show that these alloys are ferromagnetic,and the Curie temperature changes with boron concentration.The maximum value of magnetic entropy change(under an applied magnetic field change from 0 to 1.5 T) is about 1/4 of metal Gd in same condition.

[Objective] This study was to investigate the effect of VEGF and its receptor Flt-1 mRNA expression in Mongolia sheep umbilical vein endothelial cells by ghrelin antisense inhibition.[Method] Experiments were divided into 4 groups:group I(blank control group);group II(liposome group);group III(SCON group:20 μmol/L sense oligonucleotide);group IV(ASCON:20 μmol/L antisense oligonucleotide).VEGF and its receptor Flt-1 mRNA expression changes were detected by using real-time fluorescence quantitative detection after 24,36 and 48 h.[Result] The expression of VEGF mRNA in group I,group II were insignificantly different at higher expression levels,and did not change significantly with the time;the expression of VEGF mRNA in group III assumed a slight decrease,but there were no significant differences between group I and group II(P0.05),the expression of VEGF mRNA in group IV(antisense oligonucleotide group) decreased significantly(P 0.05);the expression of VEGF receptor FLT-1 mRNA was similar to that of VEGF.[Conclusion] Antisense inhibition ghrelin has a downward effect to the expression of VEGF and its receptor Flt-1 the mRNA.

The objectives of this study were to assess the mRNA expression and protein location of IGF receptors and its ligands in bovine oocytes and different stages of preimplantation embryos, and then evaluate the effect of different concentrations of IGF-II when added to either the maturation or culture medium on in vitro embryo development. For the assessment of mRNA expression by RT-PCR three replicates each of 100 oocytes, and 60 embryos at each of the 2-cell, 8-cell, morula and blastocyst stages of development were used. Immunocytochemical techniques were used to study the location of IGFs and their receptors for COC, oocytes, and embryos at the same stages of development (n = 25). The effect of supplementing maturation medium with IGF-II was examined using groups of 20 oocytes exposed to 0 (control), 10, 20, 50 or 100 ng IGF-II/ml medium. Each treatment was replicated five times. To study the effect of IGF-II added to culture medium, groups of 10 zygotes were cultured in the presence of 0 (control), 50, 100 or 150 ng IGF-II/ml medium and the treatments replicated four times. The results showed that IGF-I mRNA could not be detected but IGF-II, IGF-IR and IGF-IIR mRNA existed in bovine preimplantation embryos. Proteins for IGF-II, IGF-IR and IGF-IIR were detected on the cell plasma membrane of cumulus cells of COC, immature and mature oocytes, and 2-cell stage embryos. They were observed in blastomere cytoplasm of 8-cell and morula stage embryos. In blastocysts, the IGF proteins were distributed in the trophectoderm but not in the inner cell mass. Adding 20 ng/ml IGF-II to maturation medium resulted in higher rates of post-fertilization development than control at 8-cell (58.2% versus 44.5%; p < 0.05) and blastocyst (37.0% versus 25.0%; p < 0.05) stages of development; and the number of viable cells per blastocyst were significantly higher (126 ± 6 versus 103 ± 5; p < 0.05). When IGF-II was added to the culture medium, no significant treatment differences were observed at 8-cell embryo stage but the development rate of zygotes cultured in the presence of 100 ng IGF-II/ml medium to blastocysts was significantly higher than that of control (30.0% versus 19.2%; p < 0.05). It was concluded that supplementation of in vitro maturation or culture media with IGF-II affects the development of bovine embryos and could be used to improve in vitro embryo production.

The poor quality of oocytes may be the main reason for the low efficiency of the current in vitro embryo production. However, efforts are required to understand the mechanisms of oocyte development, which is believed to be largely regulated by apoptosis in vivo. The aim of this study was to investigate the levels of apoptosis in bovine immature oocytes with different developmental potentials and to determine whether early apoptosis in bovine oocytes is correlated with their subsequent development. Cumulus-oocyte complexes (COCs) were selected and classified into four groups according to oocyte cytoplasm and cumulus status. Early and late stages of apoptosis were detected by Annexin-V and TUNEL staining, respectively. Developmental competence was evaluated by nuclear maturation (MII) after in vitro maturation and development rates in different stages following in vitro fertilization. Meanwhile, the transcripts of Bcl-2 and Bax genes were carried out in immature oocytes by real-time RT-PCR. Results indicated that Annexin-V-positive oocytes were detected in various groups at different percentages, and Group III showed the highest positive ratio. No TUNEL-positive oocytes were found in any immature COCs. Group III oocytes demonstrated the highest nuclear maturation, cleavage, blastocyst, and hatching blastocyst rates. Meanwhile, Group III oocytes exhibited the highest Bax (initiating apoptosis) transcriptional level and the lowest Bcl-2 (preventing apoptosis) transcriptional level. Taken together, Annexin-V and quantitative PCR results indicated that early apoptosis was beneficial for developmental competence, while TUNEL staining showed that none of the immature oocytes were undergoing late-stage apoptosis. This is the first time that Bax and Bcl-2 transcripts were characterized in the immature bovine oocyte, and results indicated that the genes are good markers of early apoptosis and embryo development. This research overthrows the traditional view that oocytes undergoing apoptosis have poor developmental competence, and the findings will facilitate oocyte selection and improvement of in vitro embryo production.