Glucocorticoids are effective and powerful anti-inflammatory substances, and make a wide inhibition on immune system. Glucocorticoids can regulate the immune system of the livestock by inhibiting the release of cytokines, inducing apoptosis, affecting immune cell differentiation and migration during the stress response, and inhibiting the immune system function of the livestock while reducing the inflammatory response, thereby which increase the risk of illness. In this article, the regulation mechanism of glucocorticoids to immune in ruminants stress response were discussed, focusing on glucocorticoid receptors expression, immune cells function and cytokines regulation, aiming to provide some references for related studies.

In this study, we investigated the single nucleotide polymorphisms (SNP) of ZP4 gene, its selective pressure and association with litter size in pigs. Totally, 328 sows and their litter size records were collected from Large White, Landrace and Landrace×Large White hybridization pig populations. Direct sequencing method was used to clone and identify the nucleotide mutation in ZP4. The generalized linear regression model was applied to investigate the correlation between ZP4 SNP and litter size.The lositan software, Tajima's testing and Fu and Li's D testing were used to detect the selective pressure of ZP4. Our results demonstrated that 27 SNPs were detected in ZP4, and A268T was significantly correlated with number of total litter size in the 3 populations (P< 0.05). A268T was only significantly associated with number of born alive in Landrace and Large White pig populations (P<0.05). We also detected that T2950C was under positive selection and this mutation was linked with A268T. Our results suggested that A268T was a direct selection marker that could be used in pig marker assistant selection.

The aim of this study was to explore the effect of MAT2B on porcine intramuscular preadipocyte differentiation by constructing overexpression vector in vitro mediated by adenovirus. A pair of exclusive primers was designed according to the GenBank sequence information of MAT2B gene, and MAT2B was amplified by PCR. The obtained PCR products were inserted into a shuttle vector pAdTrack-CMV, then the gene was identified by sequencing. The results showed that shuttle vector (pAdTrack-CMV) and backbone vector (pAdEasy-1) were in homologous recombination, and the adenovirus recombinant vector (pAd-MAT2B) was constructed successfully. Then the recombinant adenovirus DNA was digested by the Pac I, the pAd-MAT2B adenovirus was produced, and we used it to infect the porcine preadipocytes. The expression level of mRNA and protein of MAT2B significantly increased. Oil Red O staining assay showed that overexpression of MAT2B promoted lipid accumulation in intramuscular preadipocyte. Moreover, the expression of adipogenic gene PPARγ and aP2 mRNA were significantly promoted when infected by Ad-MAT2B. The results suggest that MAT2B is overexpressed in expression vector in vitro mediated by adenovirus, and MAT2B play a positive role during porcine intramuscular preadipocyte differentiation.

To identify the pathways associated with body weight and average daily gain, we conducted the genome-wide association study(GWAS) and SNP ratio test(SRT) of F2 populations derived from a local Chinese breed (Beijing-You chickens) and a commercial fast-growing broiler line (Cobb-Vantress). In this study, the body weight of F2 chickens were measured at 14-day-old, 28-day-old, 56-day-old and 93-day-old, and the average daily gains of each period were calculated, respectively. The GWAS of body weight and average daily gain were carried out. The SRT was performed using the significant SNPs obtained from the GWAS. The results showed that biosynthesis of steroid hormones, metabolism of nicotinic acid and glycolysis/gluconeogenesis were genome-wide significantly associated with 14-day-old, 56-day-old and 93-day-old body weight(P<0.05), respectively. Specially, amino acid metabolic processes were also associated with the body weight(P<0.05) in each period. The enriched pathways by SNPs associated with daily gain were the most abundant in 42-56 days, these pathways were enriched in TCA cycle, steroid biosynthesis, steroid hormone biosynthesis, oxidative phosphorylation, inositol phosphate metabolism and glycerophospholipid metabolism. In brief, biosynthesis of steroid hormones plays an important role in the rapid growth of body weight of broiler, and a large number of amino acid metabolic processes are also associated with average daily gain.

This study aimed to evaluate the conservation status of Luyuan chicken breeds which were saved in the national chicken genetic resources and Zhangjiagang Luyuan chicken conservation farm, respectively. The genetic differences of Luyuan chicken populations between national chicken genetic resources and Zhangjiagang Luyuan chicken conservation farm were analyzed by identifying SNP markers and calculating genetic statistics based on RAD-seq simplified genome sequencing technology. The results showed that 395 021 and 428 314 SNP markers were identified in two populations after two steps of data quality control. The average heterozygosity of two Luyuan chicken populations were 0.211 1 and 0.206 8, respectively. The genetic differentiation coefficient of two Luyuan chicken populations was 0.005 6. Results of cluster analysis based on Structure model showed that two Luyuan chicken populations were always clustered together and no individual was separated. These results indicated that the difference between the two populations was not significant(P>0.05). Moreover, the inbreeding coefficient of the two populations were 0.178 8 and 0.193 5, respectively. The relative high inbreeding level could be caused by the smaller scale of the initial population (rescuing conservation). The selection signal analysis found that there were some differentiation between two Luyuan chicken populations on 1, 2, 5, Z chromosomes (locus). 58 selected areas and 96 candidated genes were identified through the Fst and θπ testing. GO and KEGG analysis showed that these candidate genes were mainly enriched in some biological pathways such as energy metabolism, signal transduction, stress and immunity response pathways, and so on. In conclusion, the method of genome-wide SNP marker can more comprehensively evaluate the conservation status. The results provide the basis for further optimizing the conservation solution of Luyuan chickens.

The research was designed to screen the promoter activity region and transcription factors of goat PMEL gene, and to provide a theoretical basis for exploring the mechanism of expression regulation of PMEL gene and provide ideas for breeding and improvement of colored goats. Using goat genomic DNA as template, PCR was used to amplify PMEL gene promoter sequence of different length fragments, and the fragment was cloned into pGL3-basic vector. The recombinant plasmid was transfected into 293T and A375 cells, the relative luciferase activity was measured by dual luciferase assay system, and the transcription factor binding sites in the core promoter region were predicted by bioinformatics. The transcription factor binding sites on the pGL3-327 plasmid were mutated by overlap-extension PCR, and the activity of mutants was verified.The results showed that 7 promoter fragments of different lengths were constructed successfully, and 6 of them had obvious promoter activity. -251/+76 region was detected by dual luciferase activity as the core promoter region. By comparing the activity of PMEL gene promoter sequence of different length fragments, the deletion of -251/-62 region made the promoter activity from the highest to none, which indicated that the region had important influence on the transcriptional regulation of goat PMEL gene. Bioinformatics analysis found that the -251/-62 region had 5 transcription factor binding sites, the 5 mutation vectors were constructed by point mutation, their activity were significantly decreased by double luciferase assay. It is suggested that these 5 transcription factors were the positive regulatory elements in goat PMEL gene transcription.The results indicate that the core promoter of goat PMEL gene is -251/+76 region, NF-1 (-206/-197), Sp1 (-186/-174), Sp1 (-151/-139), CREB (-91/-82) and Sp1 (-82/-71) binding sites are positive regulatory elements of goat PMEL gene.

The aim of this study was to establish the miRNA database of cumulus cells in GV/M Ⅱ stages of buffalo oocytes during maturation in vitro, and then analyze the differential-expression miRNAs of cumulus cells between GV and M Ⅱ stages of oocytes to provide scientific basis for further understanding the important role of cumulus cells in buffalo oocytes maturation. Total RNAs of cumulus cells in GV/MⅡstages were extracted, respectively, and subjected to small RNA sequencing by Solexa sequencing, the miRNA data were then analyzed through bioinformatics. The results indicated that the miRNA expression profiles in GV/MⅡcumulus cells were successfully constructed. There were 24 up-regulated and 45 down-regulated miRNAs in cumulus cells in MⅡ stage compared with those in GV stage. The expression profiles of 8 randomly selected differential-expression miRNAs examined by qRT-PCR was agreement with those by RNA sequencing. Total of 276 enriched signaling pathways related to the miRNA of the cumulus cells were analyzed by miRNA target gene prediction and KEGG enriched pathways. The top 20 enriched signaling pathways were summarized and we found that the differential-expression miRNAs played roles in cumulus mainly through cell proliferation and apoptosis, material meta-bolism, cell junction as well as other unknown pathways.

In order to explore the effect on milk fat synthesis and the expression of key genes of milk fat synthesis in bovine mammary gland epithelial cells co-cultured with umbilical cord mesenchymal stem cells, 8 groups were divided in the study: UC-MSCs and BMECs co-cultured under the condition of no treatment group, IGF-1 R inhibitor AG1024 treatment group, Janus kinase activators of transcription (JAK/STAT) pathway inhibitor AG490 treatment group and AG1024+AG490 treatment group, control group: BMECs alone cultured under the condition of no treatment group, IGF-1 R inhibitor AG1024 group, Janus kinase and transcription activating factor (JAK/STAT) signal pathway AG490 group and AG1024+AG490 treatment group. The IGF-1, Triglyceride (TG) content of each group supernatant were determined, the relative expression abundance of Acetyl-CoA carboxylase A (ACACA), fatty acid synthetase (FASN) and sterol regulatory element binding proteins (SREBP 1) mRNA were detected by RT-PCR. Results showed that the IGF-1 and TG content of co-culture group were significantly higher than control group (P<0.05); AG1024 treatment had a extremely significant effect on inhibiting IGF-1, and the TG content and the relative expression abundance of ACACA, FASN, SREBP 1 mRNA were significantly decreased(P<0.05); AG490 had no significant effect on the relative expression abundance of ACACA, FASN, SREBP 1 mRNA (P>0.05); AG1024 and AG490 co-treatment were not significant difference for each index than AG1024 treatment alone. (P>0.05). In conclusion, umbilical cord mesenchymal stem cells can promote milk fat synthesis and the expression of key gene in bovine mammary gland epithelial cells via IGF-1, but JAK2/STAT5 signaling pathway is not involving in the regulation of umbilical cord mesenchymal stem cells on milk fat of bovine mammary gland epithelial cells.

The study was to explore the effects of epidermal growth factor (EGF) on the apoptosis and motility of yak frozen sperm, the development competence of embryos after in vitro fertilization (IVF). Frozen-thawed spermatozoa of yak was incubated at 37.5 ℃ for 1 h in Tyrode's bicarbonate-buffered medium with EGF at different concentrations (0, 50, 75, 100, 150 and 200 ng·mL^-1). Sperm motility was measured by a computer-assisted sperm analyzer system; the expression of Bax and Bcl-2 in sperm were examined by qRT-PCR and Western blot; the development competence of embryo was also evaluated by using cleavage and blastocyst ratio after IVF. Our results showed that: 1) EGF dramatically enhanced spermatozoa motility and fertilized egg cleavage ratio (P<0.05), which were dose-dependence with EGF; 2) The Bcl-2 level was enhanced significantly with EGF at 75-150 ng·mL^-1 (P<0.05), while the Bax was reduced (P<0.05). In conclusion, EGF inhibited the apoptosis and increased the spermatozoa motility of yak frozen sperm during in vitro capacitation, but also enhanced the development competence of embryo after IVF, of which the optimal concentration was 75-150 ng·mL^-1. The present study was contributed to improve the yak embryos production in vitro referring to the growth factors.

The study aimed to explore the effects of food restriction on the expression of RGMb and BMP system members in the uterus of Hu ewes. Firstly, qPCR were applied to investigate the RGMb expression profile in different tissues of 3-month-old Hu ewes, IHC were used to detect the expression of RGMb in uterus. Then Hu ewes on 35 days of pregnancy (d35) were divided into 2 groups: ewes in the control (C) group were fed with 100% NRC and ewes in the restriction (R) group were fed with 50% NRC. On 110 days of pregnancy, uterine tissues (n=8) were collected to evaluate the expression of BMP2, BMP4, BMPR1A, BMPR1B, BMPR2 and RGMb by qPCR and WB. qPCR results showed that RGMb mRNA were detected in 14 tissues of 3-month-old Hu ewes, and the relative expression was greater than 0.5 in uterus. IHC staining showed that RGMb protein were mainly expressed in the endometrial luminal and glandular epithelial cells of Hu ewes. The uterine expression of RGMb protein in the R group was significantly lower (P<0.05) than that in the C group, while there was no significant differences in RGMb mRNA abundance(P>0.05). The expression of BMP4 and BMP2 mRNAs in the R group were higher (P<0.05) than those in the C group. However, the expression of BMP receptors(BMPR1A, BMPR1B and BMPR2) significantly decreased in the R group(P<0.05). The results indicate that food restriction affect the expression of BMP system members, including the RGMb, suggesting RGMb accompanied with BMP system may be involved in the regulation of uterine hemeostasis, which will set up experimental evidences for the further study on the regulation mechanism of BMP system in the uterus.

The purpose of this study was to explore the effect of different additives on natural grass silages, and improve the utilization of natural grass silage for guiding the production and utilization of natural grass. The natural grasses at full-bloom stage in meadow steppe were used as silage materials, and 6 treatments were designed, SLAB (vacuum bags, lactic acid bacteria(adding 2×10⁵ cfu·g^-1)), SCE (vacuum bags, cellulase(adding 0.8 g·kg^-1)), SCK (vacuum bags, without adding, control), BLAB (silo, lactic acid bacteria (adding 2 × 10⁵ cfu·g^-1)), BCE (silo, cellulase(adding 0.8 g·kg^-1)), BCK (silo, without adding, control), each group had 3 replicates, and after ensiling for 60 d, the fermentation quality, microorganisms population and chemical composition were analyzed. The results showed that all treatments with additives showed good silage effects. Lactic acid bacteria(LAB)-treated and cellulase(CE)-treated could significantly increase the content of lactic acid bacteria, lactic acid and lactic acid/acetic acid(P < 0.05), the content of lactic acid of LAB-treated were higher than that of CE-treated, the additives increased the preserved rate of CP (P<0.05) and significantly increased the utilization rate of water-soluble carbohydrate (WSC) (P<0.05), significantly decreased the pH, NH₃-N/Total N (AN/TN) and ADF (P<0.05), and significantly decreased the population of yeasts (P<0.05), the content of Ash were not significantly different from each other (P>0.05). The results indicate that lactic acid bacteria is more suitable for natural grasses silage, and it can be popularized and applied in the pastoral areas from small-scale silage to large-scale silage for natural grasses.

Difference of P1 and 3A gene sequences of different hosts-adapted strains type O Foot-and mouth disease virus (FMDV) were identified,and the trend of genetic variation were studied to find the genetic mutation of P1 and 3A genes of different hosts-adapted FMDV. FMDV O/XJ/10-11 strain was inoculated into bovine, neonatal rat, swine and BHK-21 cell line to obtain corresponding adapted virus strains. The RNA of FMDV in each adapted virus was taken as template for reverse transcription and amplification of P1(1A, 1B, 1C, 1D)and 3A genes. Fragment was purified and recovered by agarose gel electrophoresis,cloned into the vector pMD19-T. Positive colonies were screened,sequenced, and the gene sequences were analyzed. The results were as follows：no deletions were found in nucleotide and amino acid sequences of different hosts-adapted virus strains,the main antigenic sites were conserved in different hosts；The P1 gene of the bovine,swine,neonatal rat,and BHK-21 cells adapted virus strains had some variations,the variation extent decreased in sequence of VP1,VP2 > VP3> VP4, and VP4 was the most conserved gene region；3A gene was more stable and showed less variation；The most varied host-adapted FMDV was from swine, followed by BHK-21 cells, bovine and neonatal rat. The results showed that there is greater variability in the gene of VP1, however, the main antigenic sites of VP1 were conserved；VP2 mutations were located in its antigenic epitope; as the storage of the original virus of FMDV, neonatal rat-adapted virus is more favorable.

The objective of this study was to evaluate the immunogenicity of inactivated vaccines of swine Japanese encephalitis virus genetype Ⅰ of YA1 and CZ strains. High titer viruses were obtained by serial passages on suckling mouse brains. Then inactivated vaccines of YA1 and CZ strains were prepared by mixing these inactivated viruses with adjuvant ISA206, respectively. Furthermore, the immunogenicity of inactivated vaccines were evaluated in mice, guinea pigs and piglets. IgG antibody, hemagglutination inhibition antibody, plaque reduction neutralizing antibody and vaccine protection rate were detected through indirect ELISA test, hemagglutination inhibition test, plaque reduction neutralization test and protection rate test, respectively. These results showed that inactivated vaccines of YA1 and CZ strains produced higher IgG antibody, hemagglutination inhibition antibody, plaque reduction neutralizing antibody, and vaccine protective rate than HW1 strain in these experimental animals. These results indicated that the immunogenicity of inactivated vaccines of YA1, CZ strains was better than inactivated vaccine of HW1 strain. Above all, the immunogenicity of the inactivated vaccine of CZ strain was the best.

To explore the function of the cellular miRNAs in MDBK cells infected with caprine parainfluenza virus type 3 (CPIV3), we compared the miRNA expression profiles in normal MDBK cells and MDBK cells infected with 10 MOI CPIV3 for 24 hours using high-throughput sequencing. GO analysis of the host target genes and KEGG enrichment were performed. The results indicated that total 37 miRNAs were obviously differently expressed in the infected MDBK cells including 18 up-regulated miRNAs and 19 down-regulated miRNAs. The five of these miRNAs were verified by RT-qPCR, the results were well matched with those of sequencing data. GO analysis of the host target genes showed that these responded miRNAs were involved in immunoregulation, biological regulation and metabolism. KEGG enrichment analysis suggested that these genes functioned in various cellular signaling pathways, including B cell receptor signaling pathway, MAPK signaling pathway, metabolic pathways, focal adhesion, cell adhesion molecules, calcium signaling pathway. Our experiment provided the data to further explore the molecular mechanism of differential expression of cellular miRNA involved in CPIV3 pathogenesis.

For a better understanding of the mechanism underlying the expression of type Ⅰ IFN induced by H9N2 influenza viruses with different pathogenicity, mRNA of TLR-7 and Mx were dynamically studied in 3 host systems of chicken which infected with strains SD/818 and SD/196 in this study. SPF chickens, SPF chicken embryos and primary chicken embryo fibroblasts were randomly divided into three groups, control group, SD/196-infected group and SD/818-infected group. The lungs, kidneys, duodenum, bursa of Fabricius, embryonic bodies and primary chicken embryo fibroblasts were collected at different time points after infection, and mRNA of TLR-7 and Mx were dynamically studied using real-time quantitative reverse transcription PCR. The results showed that transcriptional level of TLR-7 and Mx in chicken host systems induced by SD/818 were significantly higher than those induced by SD/196 except expression of TLR-7 at chicken embryos. The results suggested that expression of TLR-7 and Mx mRNA in chicken host systems were induced by H9N2 influenza virus with different pathogenicity, and transcriptional level of TLR-7 and Mx induced by SD/818 were higher than those induced by SD/196.

The study was performed to investigate the regulation of cyclic GMP-AMP synthase (cGAS) on Mycobacterium bovis infected murine bone marrow derived dendritic cell (BMDC). The murine bone marrow cells were cultured and induced into DCs in vitro. Then BMDCs were infected by Mycobacterium bovis to establish infection models. Three groups were designed for the in vitro study. They were control group (BMDC control), infection group (M. bovis infected BMDC) and silence group. In silence group, BMDC cGAS gene was knocked down via siRNA and then cells were infected similar to infection group. Flow cytometry was used to analyze the expression of surface markers. In cGAS pathway, STING, TBK1, p-TBK1 and IRF3 were determined by Western blot and Immunofluorescence, and the cytokine production in cell supernatant was assessed by ELISA. The data showed that M. bovis induced higher expression levels of the surface markers CD86, CD80, CD40, MHC-Ⅱ and cytokine production IFN-β, TNF-α, IL-12p70, IL-6 in BMDC. Meanwhile, the cGAS pathway was activated and induced higher expression of related protein, however corresponding data reduced significantly in silence group. Our research indicated that cGAS pathway can be activated by Mycobacterium bovis when BMDC was infected, and cGAS contribute to maturation and activation of BMDC.

To identify the causative agent infecting the bamboo rats on a farm in the Guilin, a strain of bacterium was isolated from the liver of diseased bamboo rats. Its morphological characteristics and the results of 16S rRNA gene sequence analysis proved that the pathogenic bacteria was Citrobacter freundii. Phylogenetic analysis indicated that the isolate was closely related to C. freundii from a two-spotted spider mite, but it was an independent branch. In a pathogenic test, the isolate was pathogenic to adult mice, with a median lethal dose (LD₅₀) of 2.8 ×10⁸ CFU, and its LD₅₀ to 10-20 days old bamboo rats was 6.3×10⁸ CFU. Results of antibiotic susceptibility testing demonstrated that the C. freundii was highly sensitive to ceftriaxone, gentamycin, amikacin, ofloxacin, levofloxacin, and was resistant to penicillin, cefazolin, florfenicol, lincomycin, deoxycycline. Histopathological observation showed that the bamboo rat's septum alveolus widened, accompanied by inflammatory cell infiltration, and angiectasis in liver and hyperemia. Outside the integument of spleen there were a large number of necrotic cells, and the swelling and granular degeneration of the renal tubular epithelial cells. These findings suggest that C. freundii is the pathogen of the dead bamboo rats in Guilin. The pathogenicity of the isolate to bamboo rats is strong.

The research was designed to analyze the linkage between the endogenous avian leucosis virus ev21 and phenotype of late feathering, as well as the promoter activity of LTR of ev21 gene. It was aimed to find the detection method for ev21 free breeding chickens. Long-range PCR was used to amplify the sequence of ev21 gene. The structure and its locus in chicken chromosome were analyzed based on the NCBI database. Two hundred and fifty-nine samples from 5 chicken lines were diagnosed for the detection of ev21. And 5' and 3' LTR were cloned into the pGL3- basic vector and were transiently transfected into A375 cells. The relative luciferase activity, which indicted the promoter activity of the transfected fragments, was detected. It was showed that the genome of ev21 long for 7 524 bp was successfully cloned and it was integrated between g.10681671-10681672 on chicken Z chromosome in reverse direction. Ev21 and late feathering were completely linked in Hy-line Gray, but were incompletely-linked in Taihang, Bashang and Hy-line Brown chicken. Especially, it was all positive in Hy-line Brown fast-feather rooster. 5' LTR of ev21 showed a high promoter activity (P<0.01), while 3' LTR did not show significantly higher activity than negative control (P>0.05). These data showed that ev21 integration was not linked with late feathering in chickens. PCR for 7 590 bp is a method for screening of ev21 in chickens. 5'LTR of ev21 had the high promoter activity.

To explore the effects of monochromatic green light on chick pineal body development and melatonin secretion, 120 chick embryos at weight of 65±3 g were selected and divided them into two groups randomly with one group hatched in monochromatic green light and the other in darkness. Both research groups conducted four repeat, each including five chick embryos, and relative tissue extracted from embryos at the embryonic age (E) of 15th, 18th and 21st day, for observation, to fulfill the objective, so as to explore the effects of monochromatic green light. The result exhibits: ①Chick embryos with monochromatic green light during incubation period had an increase in birth weight of 11.19%-21.41% (P<0.05);②Monochromatic green light promoted the development of pineal parenchymal lobules;③Expression of AANAT mRNA, key of melatonin synthesis increased as the embryos developed. Compared with E15 group and E18 group form the darkness group, melatonin secretion of E21 group increased obviously by 29.84%-47.06% (P<0.05), however, no significant difference between E15 and E18; In green light group, the AANAT mRNA expression of E18 group was significant higher by 17.76% than that of E15 (P<0.05), E21 was significant higher by 26.37%-48.81% than E15 and E18 (P<0.05); Significant differences were found between green light group and the darkness group, green light group higher by 12.85%-15.95% than the darkness group (E18-E21, P<0.05); ④Plasma melatonin increased as the embryo developed, in the darkness group, E21 was 2.6 times of E15 and 1.9 times of E18; In green light group, E21 equaled to 2.8 times of E15 and 1.8 times of E18; and for E18 and E21, plasma melatonin of green light group was higher than that of darkness group by 13.13% and 18.20% (P<0.05); Plasma melatonin was associated with plasma growth hormone notably (P<0.001). Providing monochromatic green light during incubation attributed to chick embryo's growth by promoting the synthesis and secretion of melatonin, and then promoted growth hormone, finally promoted chick embryo's development.

The present study aimed to investigate the effects of (一)-Hydroxycitric acid (HCA) on cells proliferation, mitochondrial ultrastructure and function in primary chicken hepatocytes. The cells were treated with 0, 1, 10 and 50 μmol·L^-1 (一)-HCA and then detected the factors related with cells proliferation and mitochondria function. The results showed that (一)-HCA treatment promoted the cell proliferation in primary chicken hepatocytes. Ten μmol·L^-1 (一)-HCA treatment significantly increased the S phase and G2/M phase cell population (P<0.01), meanwhile it increased the cyclin mRNA expression level when compared to control group. No significantly changes were observed on the mitochondrial morphology, quantity and membrane potential in primary chicken hepatocytes following 1-50 μmol·L^-1 (一)-HCA treatment (P>0.05), while (一)-HCA treatment significantly increased the activities of succinate dehydrogenase and citrate synthase in primary chicken hepatocytes (P<0.05). These results indicated that (一)-HCA treatment promote the primary chicken hepatocytes proliferation by increasing cyclin mRNA expression, whereas it increase the energy metabolism by enhancing the activities of succinate dehydrogenase and citrate synthase in primary chicken hepatocytes.

This study was conducted to investigate the effect of sodium fluoride on the glutathione antioxidant system of mice testis. Twenty-four 3 weeks old ICR male mice were randomly divided into control group and 3 fluoride groups. The four groups were orally administrated with 0, 25, 50, and 100 mg·L^-1 NaF for 60 days. After the exposure treatment, the level of T-AOC, ROS and MDA, the activity of GPx, GST and GR and gene transcription of GPx1, GPx4, GST-mu5 and GR in the testis were detected. The mitochondria, endoplasmic reticulum and Golgi apparatus were observed by electron microscope. Results were as follows: Compared with the control group, the contents of T-AOC was decreased, the contents of ROS and MDA were raised, and the activity of GPx, GST and GR were reduced, and the relative mRNA transcription of GPx1, GPx4, GST-mu5 and GR were down-regulated. It was showed that the antioxidant capacity of testis were decreased and in an obvious oxidative stress state, which related to the decrease of the enzyme activity of glutathione antioxidant system and its related gene transcription.

This study was conducted to establish cells lines stably expressing porcine GM-CSF. The primer of porcine GM-CSF was designed according to the sequence published in NCBI, the open reading frame (ORF) was cloned by RT-PCR method. The porcine GM-CSF gene cloned consisted of 435 bp, and the ORF of porcine GM-CSF encoded a protein of 144 amino acids. The GM-CSF polypeptide had an estimated molecular mass of 16.3 ku, PI of 7.15 and displayed a high homology to Ovis aries(77.1%), Equus caballus (73.6%), Felis catus(72.2%), Bos taurus(71.5%), Canis lupus familiaris(71.3%)and Homo sapiens(70.8%), respectively. After the digestion of pIRES2-EGFP vector by EcoR I and BamH I enzyme, the ORF of porcine GM-CSF was inserted and named pIRES2-EGFP-pGM-CSF. Following, the pIRES2-EGFP-pGM-CSF was transfected into porcine intestinal epithelial cell line IPEC-J2, which was then screened by G418. Consequently, the expression of GM-CSF mRNA in transfected cells was significantly increased compared to control cells and after 24 h of transfection(P<0.01), and transfected cells also showed high expression of green fluorescent. After G418 selection and expansion (positive clone) for 30 passages, the expression of GM-CSF mRNA was increased to control compared cells. We concluded that the eukaryotic expression vector pIRES2-EGFP-pGM-CSF was constructed successfully and a cell lines that show the stable expression of porcine GM-CSF was established.