Calcium-dependent protein kinases (CDPKs) are a large gene family, which is one kind of serine-threonine protein kinases. CDPKs have a diverse array of functions in various plants and many protozoa. With the development of bioinformatics, molecular biology and gene engineering, increasing numbers of researches about CDPKs were published recently. Increasing evidence suggests that CDPKs can regulate many crucial steps of parasite’s life cycle including host cell invasion and egress, gamete formation, and gliding motility. The special structure compared with proteins in human and mammal makes CDPKs an ideal target for novel vaccine and anti-parasite therapeutic drugs. This article reviews the structures, functions and applications of Apicomplexa’s CDPKs focusing on Plasmodium, Toxoplasma gondii and Eimeria, and prospects the research and application tendency, in order to provide references for the research of the pathogenesis and biological agents against Apicomplexan parasites.

The aim of the study was to generate a transgenic swine fibroblast cell line of pepsin- and trypsin-toleranceing. After culturing, transgenic yeast fermentation broth was collected to detect the enzyme activity under the condition of pH2.0 for pepsin treatments with different concentrations and pH7.0 for trypsin treatments with different concentrations, respectively. The expression vector containing phytase gene was packaged in lentivirus and then infected swine fibroblasts. After subculturing, positive cells were screened with flow cytometric approach and cultured. The results showed that more than 70% of phytase activity remained after treatment with pepsin and more than 80% activity was remained when treated with trypsin. Lentivirus was packaged with 3.75×10⁷ titer and transfected into porcine fibroblast cells, with 1.2% positive rate obtained. PCR assessment indicated that the exogenous gene was inserted into the chromosome of the swine fibroblast cells successfully. Moreover, RT-PCR evaluation suggested that the phytase gene expressed in the transcript level. In short, the study provides a fast and effective approach for preparing phytase transgenic cell line, as well as a foundation for further breeding transgenic pig.

 The localization of Piwi protein in eukaryotic cells was conducted by constructing two eukaryotic expression vectors, aimed to provide basis for further study on the biological functions of Piwi protein. CDS of Piwi gene from Langshan chicken testicular tissue was cloned by Reverse Transcript-PCR. Fusion expression vector containing the enhanced green fluorescent protein (EGFP), pEGFP-C1-Piwi, was constructed; then was transfected into NIH-3T3 with Lipofectin PEI. Meanwhile, the eukaryotic expression vector pcDNA3.1-Piwi was also constructed successfully, and then Piwi protein expression was detected in NIH-3T3 cells by indirect immunofluorescence assay. CDS of Piwi gene was cloned successfully, and the sequence size was 2 604 bp, which was similar with GenBank. Fusion expression vector pEGFP-C1-Piwi expressed in the whole NIH-3T3 cells, while Piwi protein of pcDNA3.1-Piwi was found to locate in the cytoplasmic of NIH-3T3 cells by indirect immunofluorescence assay. Piwi protein mainly expressed in the cytoplasmic of NIH-3T3 cells, and indirect immunofluorescence assay was more reliable than the EGFP reporter gene method, which was fit for investigating sub-cellular localization of target protein.

This study aimed to introduce a practical method used to establish commercial dorper sheep strains that could meet diverse market demand from an original population. The specific steps included: (1) Using single-trait animal model BLUP to estimate the breeding value of the traits related to establishing the strains; (2) Using principal component analysis to extract component of the traits studied in the experiment which could explain over 85% variance; (3) Explaining the practical meaning of the every component based on the coefficient in the expression of principal component value to determine each of the principal component may be used as the basis of which strains establishment; (4) Selecting individuals in dorper sheep population to establish strains according to their standardized principal component value and standards of the strains. According to practical demand, the existing dorper sheep population were divided into long carcass, wide carcass and fat lamb strains in this experiment, and the results was similar with that of dividing strains based on estimated breeding value of the traits related to strains establishment. Without considering the economic weight of the traits, the BLUP and principal component analysis are applicated in the strains establishment from an original population.

To meet the seasonal regulation of production management and to explore the variation features of milk compositions and some related traits, based on the DHI data and derived data of Chinese Holstein lactating cows in the north of China, the data were grouped by parities and the natural months and the abnormal ones are deleted to obtain complete data 6 520 sets which contain 9 traits-daily milk yield(DMP), milk solid percentage(MSP), milk fat percentage(MFP), milk protein percentage(MPP), milk lactose percentage(MLP), somatic cell count(SCC), body condition score(BCS), lossed milk production(LMP) and fat-to-protein rate(FPR). The natural month, parity and their interaction were assumed as factors affecting the 9 traits. A GLM variance analysis method of SAS software showed that both of the natural months and lactation parities affected the above 9 traits significantly (P<0.000 1, or P<0.001, or P<0.05). However, the interaction between parities and the natural months showed no significant effect on MFP, MPP, MSP, SCC and FPR(P>0.05)while their interaction showed significant effect on DMP (P<0.000 1), MLP, BCS and LMP(P<0.05). The Duncan multiple comparison of natural months showed that DMP(23.58 kg·d^-1), MSP(12.35%), MPP(3.02%) and MFP(3.81%) all were the lowest in June and SCC was the highest (385.2×1 000·mL^-1) in August and LMP was the highest (1.12 kg·d^-1) in November and FPR was the highest (1.32) in February which means the cows consumed the body fat quickly. The Duncan multiple comparison of parity showed that MSP, MPP and MLP dropped rapidly in parity 4 (P<0.05). The SCC went up significantly in parity 4 and LMP increased significantly following the parity (P<0.05), and this means that the quality of the milk and sanitation indexes of milk production deteriorated and the milk loss production increased following the parity. Secondly, the canonical correlation analysis of the 9 traits showed that BCS were high positive correlation with SCC (0.830 6) and LMP (0.836 0) while SCC and LMP were high positive correlation (0.786 1). Thirdly, the relation equations between MSP(%) or MLP(%) and the natural months in mixed cow herd were built using Model Wood (MSP=12.862x^{－0.031 7}*e^{0.004 59x}, MLP=4.982 4x^{－0.019 6}*e^{0.001 06x}, x as month). The change patterns of milk composition and related traits in different natural months and parities obtained from the data provide scientific evidences for regulating feeding management and nutrient supply for cows accurately.

The objective of this study was to establish a rapidly multiplication system of BMY cattle by the technology of ovum pick-up (OPU)-in vitro embryo production(IVP)-embryo transfer(ET). 14 BMY cattle with non-pregnancy, healthy and multiparous were selected for OPU once under whole year grazing in the artificial grasslands. Oocytes were matured in vitro in TCM-199 with 5% (v/v) fetal calf serum (FCS) and in vitro fertilization in Fert-TALP medium; zygotes were cultured in synthetic oviduct fluid (SOF) with 5% (v/v) FCS for embryo production. 81 BMY recipients were picked out for estrus synchronization treatment using CUE-MATE^TM (Controlled intravaginal progesterone-release device) + estradiol benzoate (EB) + follicle-stimulating hormone (FSH) + prostaglandin F_2α analogue (PG), and recipients with a well-developed CL were transferred by BMY fresh embryos derived from OPU-IVP. The result showed that: ① Average donors with OPU were obtained 23.50 oocytes, and 85.7% donors offered more than 10 oocytes. Meanwhile, average blastocysts and available embryos of IVP were 5.21 and 4.00, respectively; Average oocytes, blastocysts, transferable embryos, rates of blastocyst and available embryo of donor ovaries with CL before OPU for 8 or 9 days were 23.57, 8.86, 7.00, 37.6% and 29.7%, respectively, significantly higher than those of control group (15.29, 1.57, 1.00, 10.3% and 6.5%, respectively, P<0.05 or 0.01). ② Ratios of corpus luteum (CL) up to A-B graded, pregnancy rate and calving rate were 69.1% (56/81), 37.5% and 35.7%, respectively. ③ Pregnancy rates of recipients with injection GnRH at the time of ET was 46.2%, higher than that of control group (without GnRH) (30.0%, P>0.05). The results indicated that BMY cows had better potential for OPU, but there was significant difference among individual donors. Moreover, the maximal efficiency of OPU-IVP was obtained by strictly selecting donors and improving technology of IVP and other measure. And the methods of CUE-MATE^TM + EB + FSH + PG for estrous synchronization were suited for applying to ET and AI in a large scale cattle herd. Finally, the technology of OPU, IVP, estrous synchronization and ET were synthetically applied to speed up the expanding propagation of fine BMY cattle.

 This experiment was conducted to obtain and analyze cDNA sequence of duck Mef2bnb (Myocyte enhancer factor 2B neighbor), and to investigate the developmental expression of Mef2bnb in duck muscle tissues. The full-length Mef2bnb cDNA was cloned from leg muscle of duck by using RACE method. Meanwhile, real-time quantitative PCR method was used to analyze Mef2bnb gene developmental expression in muscle tissues of duck, which from embryo ten days to one week after birth．The results showed that full sequence of duck Mef2bnb gene was 935 base-pairs(bp) including a 5′untranslated region(UTR) of 51 bp and 3′UTR of 518 bp, a complete open reading frame (ORF)of 366 bp encoding 121 amino acid (aa) residues. The structural analysis indicates that there was no signal peptide in this peptide chain, and the amino acid from 1 to 117 was a NEP domain which was conservative between the Mef2bnb of duck and other animals. Moreover, the different expression levels of Mef2bnb were found in chest muscle, leg muscle and heart tissue. The expression of Mef2bnb in chest muscle was higher than that in leg muscle at the same stage. It was deduced that duck Mef2bnb may have the function enhancing fiber Ⅱ formation, besides, the high expression in heart implied that Mef2bnb might relate to the process of heart development. Therefore，the results of this work may lay the foundation for further study on the structure and the role of Mef2bnb gene in muscle tissues in duck.

 This study was conducted to investigate the effects of the addition of dietary natural clinoptilolite (NCLI) and modified clinoptilolite (MCLI) on the antioxidant capacity of gut, meat quality, fat deposition and carcass characteristics. A total of 240 one-day-old male chicks were randomly assigned to 3 treatments, each of which comprised 8 pens of 10 chicks per pen. Birds in the control group were fed the basal diet, while those in the experimental groups were fed basal diets supplemented with NCLI at 2% (NCLI group), or MCLI at 2% (MCLI group), respectively, for 42 d. The random block experiment design was carried out. The blood ammonia, antioxidant capacity and meat quality were examined. The results showed that: compared with control group, the content of MDA in the serum, the jejunal and ileal mucosa were significantly reduced (P<0.01), and the content of serum GSH-Px and T-SOD increased, the content of serum MDA decreased in MCLI and NCLI groups, respectively; there were significant difference on the content of MDA, GSH-Px, T-SOD in the intestinal mucosa and the content of MDA in the serum among three groups (P<0.01). There were no significant difference on the content of GSH-Px, T-SOD in the serum (P>0.05) between the MCLI and NCLI groups, but the content of T-SOD in the MCLI and NCLI groups were higher than the control group (P<0.01). Supplementation with NCLI and MCLI had no significant (P>0.05) influence on the serum T-AOC content compared with those in the control group. The content of intestinal mucosa T-AOC in the MCLI group were found to be higher (P<0.05 or P<0.01) than those in other groups. However, supplementation with NCLI had no significant influence on the content of T-AOC in the intestinal mucosa(P>0.05) compared with those in the control group. There were no significant differences on the content of thight muscle T-SOD and T-AOC, the content of breast muscle T-AOC among three groups (P>0.05). Compared with the control group, supplementation with NCLI or MCLI had significant (P<0.05 or P<0.01) effects on the content of breast muscle T-SOD, but there were no significant differences between the NCLI and MCLI groups (P>0.05). Compared with the control group, supplementation with NCLI and MCLI had no significant (P>0.05) influence on the breast, thighs, abdominal fat, subcutaneous fat thickness, intermuscular fat width and the meat quality of AA broiler chickens. No effect of NCLI and MCLI were found on pH₂₄, drip losses, cooking loss, shear force, L^*, a^* and b^* (P>0.05). These results indicated that the supplement with NCLI or MCLI could significantly increased the antioxidative capacity of gut, protect the intestine mucosa barrier, and had no effects on the fat deposition, meat quality and carcass characteristics.

One Tembusu virus named BZ was inoculated to 7-day-old ducks. One week later, the incidence rate of 100% and the mortality rate of 80% occurred. Most of duck organs showed the systemic symptoms of congestion, hemorrhage and necrosis. The pathological changes showed severe liver parenchymal degeneration and necrosis; Spleen lymphocytes partial reduced; Renal tubular epithelial cell swelled; Pulmonary congestion, a large number of cells overflowed; Visible coagulation necrosis in the pancreas; Brain congestion and edema, meningeal inflammatory cell of cerebellar infiltrated. Compared with those of control group, the activities of serum alanine aminotransferase(ALT), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT), lactic dehydrogenase (LDH) and concentration of uric acid (UA) in virus-attacked ducks were obviously increased. The results showed that the pathogenic mechanisms of the virus may be associated with cell necrosis and multiple organ injury and exhaustion.

In order to investigate the influence on the mRNA expression level of apoptosis related factors in porcine peripheral blood mononuclear cells (PBMC) following the co-infection with porcine circovirus type 2 (PCV2) and porcine parvovirus (PPV), and clarify the mechanism of PCV2 and PPV co-infection, and the interaction of the host and virus，we used PPV and PCV2 to co-infect the swine PBMC in vitro, then measured and analyzed the viral titre, and the transcript level of cytokines of Bcl-2, FasL, p53, Caspase-8, PBR and TNF-α in mRNA level using relative quantification real-time PCR. The results were as follows: PCV 2 and PPV could infect the swine PBMC in vitro, and the virus replication levels of PCV2, PPV in the PCV2/PPV co-infection group were highest 24 h post inoculation (p. i., P<0.001). The transcript levels of Bcl-2, FasL, p53, Caspase-8, PBR and TNF-α were increased in the PCV2, PPV and PCV2/PPV co-infection groups. The mRNA transcript levels of PBR and p53 of the PPV/PCV2 co-infected group were significantly higher than that of PCV2 or PPV infection alone at 3 h p. i., and also with the higher expression levels of FasL in 12 h p.i., Bcl-2 and Caspase-8 expression in 24 h p.i. (P<0.05). Furthermore, the mRNA transcript levels of TNF-α of the PPV/PCV2 co-infected group showed significantly higher level than that of PPV infection alone (P<0.05), but there is no significant increase when compared with PCV2 infection alone. PCV2 and PPV co-infection could increase the mRNA expression level of the apoptosis related factors, and accelerate the lymphocyte apoptosis. This research provides the basis for further study of the mechanism of PCV2 and PPV co-infection.

This experiment was conducted to build the neuraminidase (NA) gene and anti-mucus virus (Mx) dual eukaryotic gene co-expression plasmid，and detect the gene expression in transfected mouse fibroblasts (NIH-3T3) cells, and to investigate the influence of the recombinant plasmid on the chicken fibroblasts (CEF ) cells. The cDNA fragment of NA and mutant Mx gene were derived from pcDNA3.0-NA, pcDNA3.0-Mx plasmid by PCR, respectively. NA cDNA fragment and Mx cDNA fragment were inserted into the multiple cloning sites of pVITRO₂ to construct the eukaryotic co-expression plasmid pVITRO₂-Mx-NA. The recombinant plasmid was confirmed by restriction endonuclease treatment and sequenced, then the mouse fibroblasts (NIH-3T3) cells were transfected. The expression of genes in pVITRO₂-Mx-NA were identified by RT-PCR and indirect immunofluorescence assay (IFA). Then the recombinant plasmid was transfected into CEF cells，RT-PCR and the micro-cell inhibition test were used to test the antiviral activity for NDV (Newcastle disease virus). The restriction endonuclease digestion and sequencing results suggested that co-expression vector pVITRO₂-Mx-NA was constructed successfully, the expression of Mx and NA could be detected in both NIH-3T3 and CEF cells. Recombinant proteins of Mx and NA protected CEF cells from NDV infection during 0-72 hours of incubation, the mutagenesis Mx or NA protein protected CEF cells from NDV infection during 0-48 hours of incubation; Compared with single-gene transfection group，co-transfection group significantly delayed the NDV infection time of CEF cells, the difference was statistically significant (P<0.05). The recombinant eukaryotic expression vector pVITRO₂-Mx-NA was constructed and expressed in CEF cell successfully, which would contribute to delaying the infection of NDV in cell level, it revealed the co-transfection of the combined genes is more powerful than single one, they had synergistic effects.

The objective of this study was to develop a colloidal gold-labeled multianalysis strip assay (Multi-strip) for the simultaneous detection of clenbuterol (CL) and ractopamine (RAC) residues. Hybridoma lines that secrete monoclonal antibody (mAb) against CL and RAC were filtered through cell fusion technology and their immunological traits were characterized. The colloidal gold-based immunochromatography competition method was employed to develop a Multi-strip, which consisted of a sample pad, a conjugate pad, a NC membrane containing two test lines and a control line, and an absorbent pad. The gold-labelled CL mAb and RAC mAb were sprayed onto the conjugate pad, and the test lines were separately coated with CL-OVA and RAC-BSA, 2 mm in distance. The visual detection limits of Multi-strip were 1 and 2 ng·mL^－1 for CL and RAC, respectively, and the results can be judged within 5-8 min. Parallel analysis of natural positive matrices with CL and RAC showed consistent results obtained from the individual strip, ELISA and GC-MS, without false-positive or false-negative cases. This Multi-strip possesses rapidity, sensitivity, specificity and simplicity, and is suitable for on-site screening and qualitative determination.

In order to further determine pathogenicity of human source S.flexneri to chicken, invasion and invasive characteristics of human source S. flexneri ZD02 strain on primary chicken intestinal epithelial cells were studied, and an in vitro model was established. Virulence of the isolated human source S. flexneri ZD02 strain was validated by invasion of Hela cell using Gentamicin resistance assay and immunohistochemistry. Invasion and invasive characteristics of ZD02 strain on primary chicken intestinal epithelial cells were researched by immunohistochemistry. Human source S. flexneri ZD02 strain could invade into Hela cells, and the invasion ratios were 1.43%, 2.43%, 2.56%, 2.72% at 30, 60, 90, 120 minutes after infection respectively. The result of immunohistochemistry showed that ZD02 strain could invade into primary chicken intestinal epithelial cells, and the invasion ratios were 1.7%, 6.2%, 8.0%, 11.2% at 1, 2, 3, 4 hours after infection respectively. Primary chicken intestinal epithelial cells treated with EGTA which disrupts intercellular junctions, significantly enhanced invasion ratio of ZD02 strain. Human source S. flexneri ZD02 strain can invade into primary chicken intestinal epithelial cells from the basolateral pole of cells, which further validated the possibility of mutual infection caused by S. flexneri between human and avian. Primary chicken intestinal epithelial cells can be used as an in vitro model to study the pathogenic mechanism of Shigella.

This experiment was conducted to explore gene expression of CD8α and its signaling pathway related genes after virus infection. The experimental animal model of infected duck hepatitis virus (DHV) was constructed by using DHV to infect 3-day-old JinDing ducklings without maternal antibody. Then the gene expressions of CD8α, MHCⅠ, MHC Ⅱ and TNFα in some tissue of different groups of DHV were detected by RT-qPCR. The specific band of conservative regions in the DHV 3D gene was amplified in morbid group and non-morbid group. This outcome showed that the infected duck hepatitis virus animal model of CD8α gene was constructed successfully. The results of RT-qPCR demonstrated that the CD8α, MHCⅠ, MHC Ⅱ genes were up-regulated in non-morbid group and down-regulated in morbid group of all tissue in different degrees, while the TNF-α gene were up-regulated in morbid group of Liver, spleen, lung, and kidney. The research showed that the expression of the CD8α gene and related gene of its pathway was altered after duck hepatitis virus infection. The results contribute to a better understanding of the duck CD8α gene regulatory role in cellular immunity.

The goal of the study is to determine the scale structure and elemental composition, and the cross-section microstructures by electron microscope of 6 kinds of wild animal fibers (Macropus, Lepus sinensis, Castor fiber, Meles meles, Canis lupus and Martes flavigula) . The results indicate that the physicochemical properties of fibers of 6 kinds of wild animals were significantly different (P<0.05), in which the cross-section microstructures were different too. The height, the thickness and the rake angle of scale of hair fibers in the 6 kinds of wild miscellaneous leathe animals were different each other. To the same animal, the height, the thickness and the rake angle of scale were different between hair fibers and cashmere fibers. Both of the needle and wool contained 4 kinds of elements, such as C, O, S, Ca. The ratios of C and O were not significantly different. The Ca content of needle was higher than wool, but the content of S was lower. Based on that, it can identify the 6 kinds of animal fur category by microstructure characteristic of wool fiber.

 In order to study the action mechanism of epimedium polysaccharide liposome (EPSL) on immunological enhancement activity, the effects of EPSL on lymphocyte proliferation and mRNA expression of IL-2, IL-4 and IFN-γ were determined by MTT method and real-time fluorescent quantitation PCR assay, taking epimedium polysaccharide (EPS) as control. The results showed that EPSL could significantly enhance lymphocyte proliferation, and at 31.250 μg·mL^-1 and 3.906 μg·mL^-1, EPSL singly or synergistically with PHA could stimulate the lymphocyte proliferation which was better than EPS. And EPSL also could increase mRNA expression of IL-2, IL-4 and IFN-γ, and were significantly better than EPS at 62.500 and 31.250 μg·mL^-1. At 62.500 μg·mL^-1, the effect of EPSL was the strongest, at 31.250 μg·mL^-1 being stronger and in a dose-dependant manner. Effect of EPSL on lymphocyte proliferation, mRNA expression of IL-2, IL-4 and IFN-γ in chicken after EPS was encapsulated with liposome

To investigate the effect of Shenqin compound to Bcl-2 and Bax genes in canine myocardium infected by canine parvovirus. Compatibility of salvia, scutellaria, glycyrrhiza and other Chinese herbal to prepare Shenqin compound injection, and to build model by artificial infection of canine parvovirus, the canines were divided into blank control group, model group, astragalus polysaccharide group and Shenqin compound group, after injecting for 7 days, inoculated canine parvovirus, observed clinical symptom in each group, the change of ultrastructure in myocardium was observed through electron microscope. The RT-PCR method were used to test the expression of Bcl-2 and Bax mRNA. The results showed: the model group had high mortality and the myocardium was seriously damaged, compared with blank control group, the expression of Bcl-2 mRNA was down-regulated at P<0.05 level, and the expression of Bax mRNA was up-regulated at P<0.01 level. In Shenqin compound group, the protective rates were high and myocardium was slightly injured, compared with model group, the expression of Bax mRNA was down-regulated at P<0.01 level, and the expression of Bcl-2 mRNA was up-regulated at P<0.01 level. This test suggested that Shenqin compound could up-regulated the expression of Bcl-2 mRNA and down-regulated the Bax mRNA to inhibit the myocardial apoptosis and protect canine myocardium from canine parvovirus damage.

The objective of the present experiment was to study the relationship between muscle histology characteristics and meat quality in Beijing-You chicken. AA broiler and Leghorn chicken were selected as comparison groups. Muscle fiber diameter (MFD), fiber bundle diameter (FBD), total fiber number (TFN), total fiber bundle number(TFBN) and the thickness of endomysium (TE) of the pectoralis major had been detected. The MFD of Beijing-You chicken was 31.42 μm and it had no significant difference with Leghorn chicken(P>0.05), but it had significant difference with AA broiler(P＜0.05) whose MFD was 45.03 μm. The TFN of Beijing-You chicken was 7.00×10⁵, it was thicker than that of Leghorn chicken(6.26×10⁵, P＜0.05) and it was finer than that of AA boiler (8.34×10⁵, P＜0.05). The shear force value (SFV), shear force energy (SFE), fiber index (FI) and tender degree (TD) of the pectoralis major was also detected in the experiment. The result of multiple comparisons was as follow. The SFE of Beijing-You chicken was 25 452 g·s^-1, it was smaller than that of leghorn chicken(27 397 g·s^-1, P＜0.05) and larger than that of AA broiler (22 705 g·s^-1, P＜0.05). The FI of BeijingYou was 5.62, it had no significant difference with that of AA broiler (5.14, P>0.05) and it was significantly smaller than that of Leghorn chicken(8.10, P＜0.05). The Pearson correlation analysis was also done between muscle fiber characteristics and meat quality traits. The correlation coefficient of SFE and FD was -0.27. The correlation coefficient of FI and MFD was -0.24. The meat quality of Beijing-You chicken was mainly decided by the characteristics of the muscle tissue.

To study the effect of sex gland hormones on the cells expression of hormone receptor to endometrial cells of goats, immortalization model of goats endometrial epithelial cells (EEC) and stromal cells (ESC) in vitro culture were established, the different levels and combinations of estradiol(E₂) and progesterone(P₄) were added in medium, without or with ESC culture medium together, PR and ER expression levels in EEC were determined by immunofluorescence technique.The results showed that compared with control group, when added P₄ alone or together with E₂, the level of both PR and ER in EEC were significantly decreased(P＜0.05), but they were slightly enhanced by E₂ adding alonely. In the EEC culture without ESC contioned medium, the expression level of PR and ER in EEC had no significant change by E₂ adding alonely.Compared with control group, the expression level of PR and ER in EEC significantly decreased by P₄ adding alonely or combined action with E₂(P＜0.05). The results indicated that when the sex hormones in coculture mode alone or together with ESC culture medium, the regulation of PR and ER in EEC were similar, and they were repressed significantly by P₄ alone.

The study aimed to clone cattle MEF2A gene and construct its eukaryotic expression vector, and provide the genetic basis for the efficient selection of Chinese cattle and the foundation of molecular marker database as well as the germplasm conservation and application. The MEF2A gene of cattle was cloned into eukaryotic expression vector, constructing recombinant plasmid of pEGFP-C1-MEF2A. Bioinformatical tools were abopted to analyz characteristics of cattle MEF2A gene and the protein. The cattle MEF2A gene, a 1 497 bp length coding region(CDS),coded 498 amino acids.The prediction demonstrated that MEF2A was composed of a MADS-box domain(No.2-56 amino acid), a MEF2 domain (No.57-77 amin acid).There was no functional domain was founden in c-terminal. An eukaryotic espression vector pEGFP-C1-MEF2A was constructed successfully.

 The aim of this study is to identify Shigella isolated from healthy slaughter yak, and to determine its pathogenicity to mice. The isolate was identified and eventually characterized by using several methods, including morphology observation, culture characteristics, biochemical tests, serotyping, 16S rRNA sequencing, electron microscopy and evaluation of pathogenicity to BALB/c mice. The results showed that morphological, culture and biochemical characteristics of the isolate is consistent with that of Shigella. The isolate was serotyped as Shigella boydii type 6. Phylogeny analysis based on 16S rRNA indicated that the isolate has close relationship with Shigella boydii and Shigella sonnei in human, and has further relationship with the Shigella from other animals. The isolate is pathogenic to BALB/c mice, and the LD₅₀ is 2.5×10^7.5CFU. The bacterium is not resistant to antibiotics commonly used. We isolated Shigella boydii type 6 from yak for the first time. The isolate is highly pathogenic and phylogentically related to human Shigella, indicating important significance of yak Shigella in public health.

In order to explore the epidemiological status of Newcastle disease virus (NDV) among wild birds in Qinling Mountains. Two hundred and fifty two throat and cloacal swabs obtained from healthy wild birds used to isolate NDV which characterized by both biological and genetic evolution analysis. Five NDVs were isolated and identified, their MDT, ICPI and IVPI were 60.0-76.8 h, 0.900-1.261 and 0.41-0.81, respectively. Deduced amino acid sequences of the cleavage sites of fusion (F) protein revealed that all strains had the same motifs (¹¹² RRQKRF¹¹⁷). Phylogenetic analysis of partial F gene (47-420 bp) showed that 5 NDVs belong to VIb genetype. By comparison of the deduced amino acid sequences of hemagglutinin-neuraminidase (HN) glycoprotein, the homology among the 5 isolates was 99.5%-99.8%, shared 91.4%-98.0%、87.1%-87.4% and 89.0%-89.3% identities with VI pigeon NDV, LaSota and F48E9，respectively. The results suggested that there are genetype VIb NDVs in Qinling area, with velogenic molecular characteristics and moderate pathogenicity index, maybe have the same origins with pigeon NDV.

This paper points out that some attentions should be paid on the abbreviations of periodical names.Comparison of periodical names of animal and veterinary sciences with abbreviations of frequently cited periodicals are listed.