Epigenetic modifications play essential regulatory roles in gene expression and transcription, cell growth &differentiation, and growth of animal. The abnormality of epigenetic modification can lead to a series of disease during development. From fertilization to implantation, epigenome of embryos undergoes extensive reprogramming, which mainly induce demethylation of 5mC and histone modifications. After fertilization, genome undergoes both active and passive demethylation in mammalian pre-implantation embryos. This paper summarizes proteins related to DNA methlation modification and mechanisms of DNA demethylation, and the dynamic changes of DNA methylation in mouse pre-implantation embryos.

The aim of this study was to explore the influence of somatic cell nuclear transfer (namely clone) operation on cardiac development of cloned Bama Miniature pigs. The proteins from three adult cloned pigs and three normal reproductive pigs were extracted, separated and identified by using comparative proteomics containing two-dimensinal gel electrophoresis (2-DE) and mass spectrometry (MS). And the functions of some important differential proteins was analyzed by bioinformatics analysis. Compared with controls, there are 11 differential proteins including 5 up-regulated and 6 down-regulated proteins in the hearts from adult cloned Bama Miniature pigs. In the present study, endothelial dysfunction of hearts from three adult cloned Bama Miniature pigs was confirmed at proteomics level.

In order to clone, sequence bioinformatic analysis and expression pattern determination of CYP19A1 gene in swamp buffalo, a pair of special primers were designed according to released sequence of bovine CYP19A1 in GenBank. The CYP19A1 gene was amplified by RT-PCR, its gene sequence character and protein structure was systemically analysised by bioinformatics techniques. The expression patterns of buffalo CYP19A1 in different tissues were also assayed with qRT-PCR. The results showed that the cloned 1 587 bp buffalo CYP19A1 gene fragment including a 1 512 bp whole length CDS (coded 503 amino acids). The sequence multialigned results showed that buffalo CYP19A1 gene shared 99%, 98%, 91%, 86% and 84% of similar nucleotide sequence with that of Bos taurus, Ovis aries, Sus scrofa and Homo sapiens, respectively. In addition, the expression pattern analysis results showed that buffalo CYP19A1 expressed in all the seven detected tissues, with the most abundant expression in brain and pituitary gland, followed by skeleton and ovary, the minimal expression in muscle was observed. The cloning and analysis of CYP19A1 gene provided an important foundation for further study regulation mechanism of CYP19A1 gene in buffalo in the future.

 The production of the α 1,3-galactosyltransferase (GGTA1) gene-deficient Wuzhishan miniature pigs will provide the valuable genetically modificated animal models for the further development of the xenotransplantation between the pig and human. Based on our previous, establishment of the fibroblast cell lines using Wuzhishan miniature pig which been knocked out single GGTA1 allele by the way of promoter-trap, then selected spontaneous loss of heterozygosity cells from fibroblast cultures of heterozygous animals using a biotin-labeled IB4 lectin attached to streptavidin-coated magnetic beads. A total of 3 122 somatic nuclear transferred embryos reconstructed with the GGTA1^-/- cells were transferred into 13 recipient pigs, four of them were pregnant, and producing 12 liveborns. Absences of GGTA1 in the cloned pigs were confirmed by PCR and Southern blotting. Flow cytometric analysis revealed that α1,3Gal antigens were not present in the cells of the cloned GGTA1^-/- pigs. The production of GGTA1^-/- pigs provided a typical paradigm and an important resource for the further development of genetically modified pigs for make organs tailored for transplantation to humans.

The aim of this study was to construct expression vector of Fat-1 in sheep fibroblasts,encoding unsaturated fatty acid desaturase driven by UbB(human sapiens Ubiquitin gen B sufamily) constitutive promoter. UbB was obtained by PCR, Fat-1 gene from Caenorhabdit elegans was optimized base on ovis aries codon，and GBHpolyA was from pcDNA3.1.These donor sequences were orderly inserted into MCS of pCMV-DsRed2-1 vector. The recombinant vector(pUbB-oFat-polyA-CMV-DsRed) was analysed by endonucleases digestion and sequencing. The linearized vector was transfected into sheep fibroblast with liposome. The positive cell was selected with G418 and red fluorescence signal,and furtherly confirmed by PCR and RT-PCR,components of PUFAs were detected by HPLC. The results showed that corrcet recombinant vector was obtained,and Fat-1 gene could been properly expressed in sheep fibroblast. The ω-3 PUFAs were greatly increased from 11.48% to 24.41% and simultaneously the ω-6 PUFAs decreased from 88.52% to 75.59%.A significantly reduction of ω-6/ω-3PUFAs ratio was observed from 7.82±0.18 to 3.10±0.03(P＜0.01). These results demonstrate that the expression vector was constructed successfully, and the sheep fibroblast line was obtained, which could encode unsaturated fatty acid desaturase, furthermore, this study may pave the way to generate transgenic sheep by somatic cell nuclear transfer technology.

The aim of the present study was to construct a salivary-glands-specific expression vector, which including dual screen markers gene and fibrolytic enzymes gene, and then it was transfected into porcine fetal fibroblast cells to provide fibrolytic enzymes transgenic donor cells for cloned pigs. The sequences of dual screen marker gene NEO-T2A-EGFP and fibrolytic enzyme gene SP-EGX-F2A-BGL1 were amplified by SOEPCR and PCR, respectively, and inserted into the salivary-glands-specific expression vector to generate pPSP-SP-EGX-F2A-BGL1-CMV-NEO-T2A-EGFP. After identification by PCR, restrictive enzymes digestion and sequencing, the vector was transfected into porcine fetal fibroblast cells with liposome, and the stably transfected cells were screened by G418 selection and EGFP and identified by PCR and Western blot analysis. The result showed that the salivary-glands-specific expression vector with dual screen marker genes and fibrolytic enzyme genes was constructed, and the stable transgenic porcine fetal fibroblast cell lines were established. The study paves the way for further research on production of cloned pig expressing fibrolytic enzymes in their salivary glands.

To explore the method for inducing rabbit bone marrow mesenchymal stem cells(BMSCs) into islet cells in vitro, BMSCs at 3rd generation were induced with dimethyl sulfoxide (DMSO) and high concentration of glucose.The morphological change of cells were observed after inducing. The islet cells were identified by Dithizone staining, the expression of insulin was detected by immunocytochemical staining. The insulin content was detected by ELISA. After induced 7 days,the cells appearred groups of cell mass. After 10 days, groups of cell mass got closely, whereas the control cells did not appeare group of cell mass. After treated with Dithizone(DTZ) and Immunocellulerchemistry (ICC), the induced cells both were positive and the control group both were negative.In ELISA tests,the insulin content of induced group were (27.82±0.43) and (27.89±0.25) mU·L^-1 at 7 and 10 days, that of the control group were (23.39±0.20) and (25.71±0.27)mU·L^-1. The difference was significant(P＜0.01) between induced and control groups. The result showed that DMSO with high concentration of glucose can induce rabbit BMSCs into islet cells in a relatively short period.

The aim of this study was to explore the method for culture and identification in vitro of the alpaca skin melanocytes， to lay a foundation for the establishment of the alpaca skin melanocytes lines, and to provide an ideal biological material for coat color genes function and somatic clone studies. Alpaca skin melanocytes were obtained by the two step digestion method of DispaseⅡ and trypsin/EDTA, and the primary and secondary culture in vitro were carried out. Morphological observation and growth curve were used to evaluate the proliferation and differentiation ability of alpaca skin melanocytes. The cells were identified with Dopa-staining, immunochemical staining, electron microscope and RT-PCR. The cells showed strong proliferation ability in the proliferative media. Dopa-staining showed that the cultured alpaca skin melanocytes had melanin synthesis, immunochemical staining, RT-PCR and electron-microscopy technology assay demonstrated that the cell differentiation was normal. The results showed that the culture system was established successfully in vitro.

The study was designed to investigate the effect of Rhodiola sachalinensis polysaccaride (RSP) on developmental competence of porcine oocytes. Immature oocytes were matured in vitro and supplemented with different concentrations of RSP, the extrusion of first polar body was treated as a symbol of nuclear maturation, then the nuclear maturation rates, oocyte intracellular glutathione (GSH) content and reactive oxygen species (ROS) level, embryonic development after parthenogenetic activation (PA) and in vitro fertilization (IVF) were conducted. The result showed that the nuclear maturation rate in each RSP treatment were higher than that of control group (83.50%±1.00%, P>0.05); The GV stage oocytes treated with 6.0 and 60.0 mg·L^-1 RSP in vitro maturation medium could significantly increase the GSH content (P<0.05), and decrease the ROS level (P>0.05); After PA, the cleavage rate of 60.0 mg·L^-1 RSP (88.44%±5.06%) and the blastocyst rate of 6.0 mg·L^-1 RSP (40.94%±8.23%) were the highest,and were significantly higher than those of control group (72.16%±7.38%, 24.06%±5.16%,P<0.05); IVF cleavage rate in each RSP treatment was significantly increased (P<0.05), IVF blastocyst rate (19.20%±3.13%) derived from oocytes treated with 60.0 mg·L^-1 RSP was significantly higher than that of control group (9.60%±0.65%, P<0.05). The results showed that adding RSP in vitro maturation medium could increase nuclear maturation rate, promote cytoplasm maturation, and then increase the developmental competence of porcine oocytes after PA and IVF.

To explore the effects of active immunization against GnRH on the hypothalamus GnRH biosynthesis and gonadal feedback regulation system in adult Sprague-Dawley (SD) rats. Thirty-six male adult SD rats at the age of 12 weeks were randomly allocated to three groups of 12 animals each. Briefly, 12 rats were immunized against GnRH with a booster vaccination 8 weeks later. 12 intact males and 12 castrated rats were not administrated and served as controls. The GnRH antibody titers and reproductive hormone levels in sera, and the content of GnRH in the median eminence were determined by radioimmunoassay (RIA). The mRNA expressions of reproduction-related genes in the hypothalamus were quantified by real-time fluorescence quantitative PCR technique. Active immunization against GnRH significantly increased serum GnRH antibody titers in eleven of twelve immunized rats, reduced serum LH, FSH and testosterone to around or undetectable levels (P<0.05), and resulted in a subcutaneously atrophy of testes in these rats (immunocastrates). Compared with intact controls, immunocastration of rats significantly reduced the content of GnRH in the median eminence and mRNA levels of androgen-receptor (AR), estrogen receptor alpha (ERα), kiss-1, GPR54 and GnRH in the hypothalamus (P<0.05). As to surgical rats, excepting the serum LH and FSH levels, and the hypothalamic ERα mRNA levels were significantly higher than those in intact rats, the remaining experimental parameters were similar to those of immunocastrates. These data firstly indicate that the feedback regulations of gonads on the hypothalamus and the synthesis capacity of GnRH in the hypothalamus are both suppressed by active immunization against GnRH.

 This experiment was conducted to evaluate the effects of phytase and heat-resistant phytase on growth performance, blood biochemical and physiological parameters in AA broiler. 4 800 1-day-old AA broilers were randomly divided into 6 groups, 5 replicates per group, and were fed with two periods experimental diets from 1 to 3 weeks and from 4 to 6 weeks, respectively. Basal diet was fed in control group, the basal diet P levels was reduced in treatment group 1, AA broilrs were fed diets with 500 and 2 000 U·kg^-1 phytase in treatment group 2 and 3, 250 and 500 U·kg^-1 heat-resistant phytase in treatment group 4 and 5. The results showed that reducing P add level of basal diet, ADG was significantly decreased (P<0.05), F/G was increased; adding phytase, ADG was increased, F/G was decreased, and the effects were better than that of control group. On growth performance, the effects of heat-resistant phytase and 2 000 U·kg^-1 ordinary phytase were similar, and better than that of treatment group 2; reducing P add level of basal diet or adding different source phytases, ALP activity significantly increased, based on this, adding phytase, P in serum and ALP activity return to the level of control group, which had no significant influence on ALB, TP, GLB, GOT, GPT and Ca in serum; different treatments had no significant effects on the T4, T3, GH, IGF-Ⅰ, PTH and CT (P>0.05); compared with control group, IGF-Ⅰin treatment group 1 was decreased, and increased in the phytase groups. Under the conditions of this experiment, we found that the ADG of broiler was improved after adding new heatresistant phytase with low P diets, and F/G was decreased. The effects of two phytases on physiological and biochemical parameters in serum had no significant difference.

The aim of the study was to investigate the expression of bovine peptide transporter I(bPepTI) mRNA in bovine Gastrointestinal(GI) tract. Relative and absolute quantitative mRNA methods were used to detect the expression of bPepTI mRNA in different parts of bovine gastrointestinal tract and to investigate its main absorption sites in the present study. Both the -ΔC_t and standard curve methods were used in relative quantification. The results of -ΔC_t method revealed no significant difference among different parts of bovine GI tract (P>0.05). Numerically, mRNA expression of bPepTI decreased in order of reticulum < omasum < abomasums < colon < rumen < duodenum< caecum< ileum< jejunum. The results of standard curve method were significantly different among different parts of bovine GI tract (P<0.05). mRNA expression of bPepTI in jejunum was significantly higher than that in ileum (P<0.05); the expression of bPepTI in ileum was significantly higher than that in other parts (P<0.05); and there were no significant differences among the other parts of bovine GI tract (P>0.05). The data from absolute quantification showed that mRNA copies of bPepTI were different in different parts of bovine tract (P<0.05), and the order from the highest to the lowest mRNA copies of bPepTI was jejunum,omasum, reticulum, rumen, caecum, duodenum, ileum, abomasums and colon. mRNA copies of bPepTI in jejunum was significantly higher than that in omasum (P<0.05), and there was no significant differences among caecum, duodenum, ileum, abomasum (P>0.05). In conclusion, results of standard curve and absolute quantification method were more believable,and jejunum, ileum, omasum and rumen may be the major absorption parts of small peptides along bovine GI tract, in which there were high mRNA expression of bPepTI.

The study was carried out to examine the genetic characteristics of a novel swineorigin influenza A (H1N1) virus isolated from Shandong province. Samples from suspected influenza-infected pigs were collected for viral isolation and identification, and then genetic evolution of HA，NA，PB2，PB1，PA，NP，NS and M of the isolate (A/swine/Shandong/07/2011) was analyzed and compared with the related influenza viruses. The results showed that sequences of 8 fragments of the isolated virus revealed >99% nucleotide identity with A/H1N1(2009) prototype strain, and its HA cleavage and receptor-binding sites were PSIQSR↓GLFGAI and 190D, 225 D, respectively, which were identifical with A/H1N1(2009) . However, compared with HA protein of A/H1N1(2009), mutation Q226R occurred in receptor binding site of the isolate. In conclusion, the results of this study provided significant information for further research on molecular evolution of novel swine-origin influenza A (H1N1) virus.

Real time monitoring information was analyzed to understand the genetic and pathogenic evolution of porcine reproductive and respiratory syndrome virus (PRRSV) in Central China during 2011-2012. RT-PCR was conducted to identify the discontinuous 29-amino acid deletion in the Nsp2 gene, which is the characteristic of highly-pathogenetic PRRSV (HP-PRRSV). The GP5 gene of 8 PRRSV isolates were cloned, sequenced and subsequently compared with that of 62 typical isolates deposited in GenBank over the years. The results showed that all the 8 isolates collected in Central China during 2011-2012 were closely related to the HP-PRRSV emerged in Southern China in 2006.

To diagnose suspected cattle rabies case and analyze molecular characteristics of the pathogen, brain tissue materials of cattle with clinical symptom from a farm in China were used. Rabies virus (RV) in brain tissue was confirmed by Mouse Inoculation Test (MIT), Hematoxylin and Eosin Staining (HE), Fluorescent antibody test (FAT) and specific nucleoprotein gene (N) RT-PCR amplification. Molecular characterization of RV strain was performed using DNAStar, Mega4.0 softwares based on N gene sequence. Results showed that this cattle disease case was caused by RV, phylogenetic tree analysis demonstrated that RV researched in study has a closer genetic relationship with DQ666306, DQ866121, DQ496219, EF556197 which were isolated in 2006 and 2007 from dog, pig and human. This paper accumulated useful materials for further studying molecular epidemiology of cattle RV in China in the future.

The aim of this study was to provide reference for genetic evolution, antigenic specificity and pathogenicity of goose parvovirus (GPV) in Anhui Province of China. The complete genomic sequences of two GPV strains isolated from Muscovy ducks (GPV Y stain) and geese (GPV E stain) in Anhui Province were obtained by polymerase chain reaction method and then aligned with the sequences of GPV and Muscovy duck parvovirus (MDPV) published in GenBank using the neighbor-joining method. The results showed that the genome of the GPV Y stain (5 106 bp) was shorter than that of the GPV E stain (5 125 bp), which was attributed to a 1-bp deletion in the ITR region and a 22-bp addition in the region (4646-4668 nt) between the end of VP3 ORF and the beginning of its poly(A) tail in the GPV E stain. The phylogenetic analyses revealed that these two strains along with those from Taiwan Province of China belonged to the GPV subgroup IIa, while most of other GPV stains isolated in mainland China were clustered in the GPV subgroup IIb. This result further confirmed the high homology of the two isolates to those from Taiwan Province. Compared with the standard virulent GPV B strain, the two isolates missed the deduced 703-705NRT glycosylation site in VP region, which may affect the viral virulence and even cause immune escape.

The objective of this study is to investigate the relationship between pathological lesion and transcription, expression and distribution of heat shock protein 60 (HSP60) in kidney of chickens infected by Marek's disease virus (MDV). Tumor animal model was successfully established by infecting 1 day old chickens with MDV. Real-time RT-PCR, histopathological, immunohistochemistrical methods were used to detect the pathological lesion, transcription level, expression level and distribution of HSP60 in the kidney. After 21 days post-infection (PI), obvious pathological damage appeared in the kidneys of chickens infected by MDV. HSP60 was mainly distributed in the cytoplasm of the oncocyte and interstitial macrophages in the tumor regions. Within the course of MD, the contents of HSP60 of effected group were always higher than blank control group and vaccine control group, which was significantly higher after 28 days, and the mostly was about 8.608 and 12.752 times at the age of 28 days. The tendency changes looked like a downward parabola, during 7 to 21-day-old, the level of HSP60 mRNA transcription of effected group was in the rising stage, and then gradually dropped. When 21-day-old the maximum was came on, which was about 1.222 and 1.179 times of two control groups. Throughout all stages the level of transcription was higher than blank control group, and during 14 to 28-day-old was significantly higher (P<0.01). The MDV infection caused resistance to infection and antitumor response in the progress of MD, the stress related kidney damage resulted in the over-expression of HSP60 in tumor lesions and surrounding tissues. A corresponding increase came to the mRNA transcription level of it in kidney tissues. The rapid expression changes of HSP60 was basic consistent with its mRNA transportation level, but not completely linear. And they were closely related with the onset and progression of tumors, which might be hallmarks to diagnose and determine the process of tumor caused by MDV.

Apoptosis and expression of bcl-2 mRNA in the immune organs of chicks infected with infectious bursal disease virus (IBDV) were investigated. The number of apoptosis cells was assessed by TUNEL method. The expression of bcl-2 mRNA was investigated by Real-time PCR. The results showed that the apoptosis cells in bursa of Fabricius, thymus and s pleen of chicks infected with IBDV from the third to seventh day post infection are significant or extremely significant higher than that of normal SPF chicks (P<0.01 or P<0.05).At the same time, the expression of bcl-2 mRNA significantly increased in the immune organs of SPF chicks infected with IBDV from the third to seventh day post infection compared with those of normal chicks (P<0.01 or P<0.05). These study indicates that IBDV can improve the number of apoptosis and the expression of bcl-2 mRNA in immune organs of chicks infected with IBDV.

This experiment was conducted to study the histopathological changes and virus antigen distribution caused by Duck hepatitis A virus genotype C (DHAV-C) in Specific pathogen free (SPF) ducklings in order to partially elucidate the pathogenesis of the virus. SPF ducklings were experimentally infected with DHAV-C and 10 sorts of organs from the infected ducklings were fixed in 4% paraformaldehyde at different time points post infection (PI). The prepared sections from 10 organs of DHAV-C infected ducklings at different time points PI, were stained with haematoxylin and eosin (HE), as well as Immunohistochemical (IHC) staining and were observed under a light microscope. The results showed that the 10 examined organs, including heart, liver, spleen, lung, kidney, intestine, thymus, bursa of Fabricus (BF), pancreas and cerebrum, all had pathological changes and virus antigen distributions. The severe pathological changes and more virus antigens were found in liver, spleen, kidney, bursa of Fabricus (BF), thymus and pancreas. Where there were more virus antigen stains, there were more severe histopathological changes. These results indicated DHAV-C causes wide damages to different duckling organs. The virus invasion to liver, kidney and immune organs thymus, bursa of Fabricus (BF) and spleen is the foundmental reason for its acute infection.

The aim of this study was to investigate the role of Toll-like receptor 4 （TLR4） in pregnancy uterus of goat. Immunochemistry SP method and fluorescent real-time quantitative PCR technology were used to study the distribution of TLR4 and the expression of TLR4 mRNA in Guanzhong dairy goat of early pregnancy (1-30 d), midtrimester of pregnancy (31-120 d) and late pregnancy (121-150 d). The results showed that TLR4 has different distribution in mucous layer, uterine muscle and uterine serosa of guanzhong goat uterus, TLR4 was mostly localized to the luminal and granular epithelium cells, there were less TLR4 positive staining cells in uterine muscle and uterine serosa; With the time of pregnancy increased endometrium epithelium cells staining gradually became lighter, the granular epithelium cells stained strongest in midtrimester of pregnancy, however, in late pregnancy the staining cells decreased; The relative expression of TLR4 exhibited low-high-low regularly change in endometrium, the level of TLR4 expression in midtrimester of pregnancy was significantly higher than that of TLR4 during other periods (P<0.01), the level of TLR4 expression in early pregnancy was lowest, which was significantly lower than that of TLR4 during other periods (P<0.01). TLR4 mRNA expressed in uterus throughout the whole pregnancy cycle, the expression level of TLR4 mRNA was consistent with the relative expression of TLR4. These results indicated that the distribution and expression in pregnancy uterus of Guanzhong dairy goat have certain rules, and that TLR4 may plays a role in regulating the immune and secretion of uterus.

 Eukaryotic expression vectors of mouse Fyn and its different mutants were constructed. Structural and functional changes of their protein products were predicted. Fyn cDNA from mouse cerebral cortex was cloned and subcloned into pMD18-T. Validated pMD18-T-Fyn^wt was used as template to construct clone plasmids of different mutants using different primers. The validated Fyn^wt and its different mutants were cloned into pCAG-MCS to get the eukaryotic expression vector pCAG-MCS-Fyn^**. Characteristics of their bioinformatics were analyzed. The complete sequence showed that the cDNA sequence of Fyn^wt is identical with that in GenBank. The fragments of Fyn mutants have fully acquired as expectation. The relative expression level of multiple Fyn in cell rised obviously （P<0.01）. Bioinformatics analysis showed that the secondary structure of protein products of Fyn mutants changed remarkably by comparison with that of Fyn^wt, which may influence the bioactivity of Fyn.

The present study was conducted to investigate the possible functions of α-galactosidase derived from Streptococcus alactolyticus strain FGM in Astragalus membranaceus fermentation. The α-galactosidase aga2 gene was cloned with homology-based cloning and its expression during A. membranaceus fermentation was estimated using the determined ideal reference gene ldh through real-time reverse transcription quantitative PCR (RT-qPCR). The results showed that the strain FGM was in exponential growth phase within 6 h and there was a rapid decline of pH value from initial 7.2 to 5.3. The bacteria stable growth phase was post 12 h, pH value was 4.5 and pH value changes were not observed from 48 h to the end of fermentation (72 h). A nucleotide segment of 648 bp was successfully obtained (GenBank No. KC202825) and its highest sequence identity was 98%. Aga2 gene expression was significantly up-regulated (P<0.05) within 24 h and reached a maximum at 24 h (6.04-fold). The aga2 gene expression was only 1.3-fold higher at 36 h. However, it showed a gradual decrease from 36 h to 60 h and was down-regulated at 72 h when it reached a minimum (0.68-fold). The results suggested that α-galactosidase produced by S. alactolyticus strain FGM not only showed some ability to hydrolyze some anti-nutritional factors α-galactosides in A. membranaceus，but also might be responsible for exopolysaccharides biosynthesis indirectly by the Leloir pathway of galactose metabolism.

The aim of this study was to study the muscle’s physiology and biochemistry characteristics and to provide data for protection and utilization of genetic resources and meat processing in yak.The difference of muscle fiber diameter, drip loss rate and muscle color were detected between two kinds of yak, and their association with pH value were analyzed. The result showed that there was no significant difference in muscle pH and water drop loss rate between the two kinds of yak(P>0.05); The muscle fiber diameter of Jinchuan Multi-vertebrate yak was less than that of Maiwa yak(P<0.05); in the two yak populations- muscle, variation trend of ΔL* , Δa* and Δb* was similar with ΔE*, ΔC* and ΔH*, respectively. There were no significant correlationship between muscle’s L* value and pH，L* and a*(P>0.05), which was related to the high Fe²⁺ content of Jinchuan Muliti-vertebrate yak’s muscle. Jinchuan Multi-vertebrate yak had better meat color than that of Maiwa yak, the former’s meat was more tender than that of the latter. The variation of L* value of yak muscle could reflects the variation of meat color well, it could be as a reference parameter to evaluate meat color and quality.

The aim of this study was to study structure and ST type of the cmp gene of C. jejuni from Yaks, pigs and chicken. The complete coding frame of cmp gene from 60 C. jejuni isolates (15 from Yaks, 22 from pigs and 23 from chicken) was cloned and analyzed. Neighbor-joining phylogenetic tree was constructed and ST types were determined according to the ST typing standard reported by literature in which one nucleotide variation in a nucleotide sequence was considered a different ST. The results indicated that there were 13 different sequence length types among 60 cmp genes cloned. A total of 7-10 Loop links, 15-20 antigen epitopic sites were predicted in these sequences. The majority of variable nucleotides and putative amino acid positions concentrated in 6 high variable areas, which located at the Loop links that exposed on the surface of C. jejuni. Forty-six ST types were identified in the 60 cloned sequences, moreover, the two strains (one from Yak and the other one from pig) recombined with the C. coli. There is strong phylogenetic variation within the C. jejuni cmp genes, and it is revealed that ST types of C. jejuni cmp gene are associated with host resources and geographic origin of the isolates.