O₂ is essential to animals, and animal’s survival is threatened when cells are deprived of O₂. Eukaryotic cells respond to low-oxygen concentrations by upregulating hypoxic genes. Mitochondria have long been considered as a likely site of oxygen sensing, and mitochondrial respiratory chain is required for hypoxic signaling, though its underlying role in this process has been unclear. Mitochondria may regulate the ROS produced by respiratory chain to control the enzyme activity of PHD, or sense oxygen through the protein tyrosine nitration reaction which is the combined effect of both ROS and NO produced by mitochondria. The mtDNA mutations, cell metabolism pathway changes and respiratory chain efficiency regulations also play important roles in adaptation to hypoxia. How mitochondria play a key role in hypoxic adaptation will be reviewed, hoping more attention will be caught on the research of hypoxic adaptation and mitochondria.

This study was conducted to detect the single nucleotide polymorphism (SNPs) of BPI gene in partial coding region in ninety-eight Sutai pigs, and to predict the effect of mutation on BPI protein structure and function.PCR-SSCP/RFLP combined with sequencing were used to detect the SNPs in exon 1, exon 4 and exon 10 of BPI gene, and bioinformatics approach was used to predict the physicochemical properties and structures of original protein or mutant protein. Refer to the cDNA sequence of BPI gene, six SNPs existed in exon 1, exon 4 and exon 10 of BPI gene, with three synonymous mutations（c.24A>G , c.54T>C and c.522C＞T） and three missense mutations (c.433C>T(Arg145Trp), c.1060A>G(Thr354Ala) and c.1151T>G(Leu384Arg)). Three missense mutations had no influence on the physicochemical properties, signal peptide, transmembrane region, glycosylation sites, secondary structure and tertiary structure of the BPI protein，but led to the change of its phosphorylation sites or the existence of other potential function sites domain. The result of Western blot experiment indicated that there was an target band at 53 ku. It was obvious that expression of BPI protein in ETEC F18-resistant group was significant higher than that in susceptible group. The base mutations in exon 4 and exon 10 of pig BPI gene affect protein function in one way or another, which may have an influence on resistance/susceptibility of the pig disease.

 This study aimed to construct integrated porcine growth hormone (pGH) inducible expression vector and to validate the induction and expression efficiency at the cellular level. pTRE-GH fragment was amplified by PCR from pTRE-GH12 vector, then the ligation of the Sal I digestion fragment to the Sal I digestion vector pCAGGS-rtTA, the recombinant vector pCAGGS-rtTA-TRE-GH12（pTTGH）was constructed. The pTTGH vector DNA transfected porcine PK15 cells, and enriched with G418, pGH mRNA expression level was determined by QRT-PCR after adding induction substrate, with doxycycline (DOX) in culture medium. The expression change was observed by QRT-PCR and Western blot assay for pGH after different concentration of DOX inducing. The results of sequencing and restriction enzyme digestion showed that the pTTGH vector was constructed successfully. Compared with control cell groups, QRT-PCR results showed that pGH mRNA expression level was the highest at 36 h after DOX adding; within a certain range of the DOX concentration, the exogenous pGH mRNA expression level showed positive relationship with DOX concentration. Nevertheless, the pGH expression level showed no obvious relationship with DOX concentration and adding or not in normal cell groups. Results of gray intensity analysis showed that pGH protein level and a certain range of the DOX concentration in culture media had positive relationship. The results showed that the vector had been successfully constructed and which could realize pGH controllable expression. This study established a foundation for preparing pGH controllable expression transgenic animal and further studying on GH affection.

Real-time PCR technique was used to study the ontogenetic mRNA expression of Lep and LEPR genes in two sheep breeds with distinct tail types (Guangling Large Tailed and Small Tailed Han Sheep), so that to discuss the probable relationship between the Lep and LEPR mRNA expression and fat metabolism. Adipose tissues from seven parts of the body(great and small omenta, tail, subcutaneous, mesenterium, perirenal and retroperitoneum) were collected from 96 animals (48 for each breed with equal sex ratios) from 2- to 12- month old at the interval of two months to study the mRNA expression. The results showed that both Lep and LEPR expressed spatiotemporally in the two breeds. As the main effects, sex and breed did not basically influenced the expression of Lep and LEPR, but the breed × age interaction affected the expression of the two genes to different extents. Although the two genes had a synergistic effect on the regulation of fat deposition and energy metabolism, their expressions were inversely regulated. These results provide the important scientific bases for further research on the genetic mechanism of fat metabolism in sheep.

The aim of this study was to clone and express the ISG15 gene of Xinjiang Wild argali, and to detect the activity of the expression product. The full length cDNA of Xinjiang Wild argali ISG15 gene was cloned by RT-PCR and RACE, then ISG15 gene was cloned into eukaryotic expression vector pPIC9K, the pPIC9K- ISG15 was transformed into Pichia Pastoris GS115 yeast genome by electroporation and the expression was induced by methanol,the expressed protein was purified by Ni²⁺chelate affinity chromatography, finally the activity of the expressed protein was detected by lymphocyte transformation test. The result showed that the full length cDNA of Xinjiang Wild argali ISG15 was 642 bp,the open reading frame was 474 bp, encoded 157 amino acids. The yeast recombinant strains GS115/pPIC9K-ISG15 was used to express ISG15, SDS-PAGE analysis showed the expressed protein was 33 ku, the expressed protein could be purified by Ni²⁺chelate affinity chromatography. The lymphocyte proliferation test results showed that the expressed product could significantly stimulate lymphocyte proliferation(P<0.05), which proved the expressed protein had biological activity.

The aim of this study was to exploit genes that play key roles during feather regeneration. In this experiment, 6 female Wanxi-white geese with 100-day-old were selected for skin samples before and 1 d after moulting. The 6 RNA samples were equally mixed for detecting the differentially expressed genes before and after moulting in Wanxi-white goose. The results showed that Wnt5a, Wnt10a and Lipoprotein receptor-related protein 3 (LRP3) genes in Wnt signaling pathway were down-regulated, and wnt receptors genes (frizzled 2 (FZD2), FZD9 and SFRP2) were up-regulated while FRZB, FZD8 and FZD10 were down-regulated 1 d after moulting in Wanxi-white goose. In the Noggin signaling pathway, NOG2 and NOG were down-regulated, and BMPR1A and BMP1 were up-regulated while BMP2, BAMPI, BMP2 and BMP7 were down-regulated 1 d after moulting. Cell cycle-related protein Cyclin B3 and Cyclin Y were up-regulated while Cyclin D3 and CDK3 were down-regulated. Other genes, such as IGF2, IGFα, IL6ST, TNFSF15, were also detected as differentially expressed genes 1 d after moulting in Wanxi-white goose. Many genes which participated in Wnt signaling pathway and Noggin signaling pathway, were detected in differential expression 1 d after moulting in Wanxi-white goose. The differentially expressed genes detected in this experiment would provide more information in the molecular regulation of downy feather regeneration. Genes screened from this experiment might be taken as key regulatory genes for breeding of goose with high-yield downy feather.

 Mouse oocyte were cultured in maturation medium to investigate melatonin(MT)could affect mouse oocyte maturation during exogenous H₂O₂.the parthenogenetic embryos were incubated with different concentrations of MT(0,10^-9,10^-7,10^-5,10^-3 mol·L^-1), every stage of development would be analyzed. The results showed：(1) The percentage of the mature oocytes (MⅡstage oocytes with a first polar body) was significantly decreased by the addition of exogenous H₂O₂ in a dose-dependent manner (>250 μmol·L^-1, 19.4% vs.92.0%, P<0.05). (2)When oocytes were incubated with MT（0.1，1.0，10.0 ng·mL^-1） in the presence of H₂O₂ (250 μmol·L^-1), MT dose-dependently blocked the inhibitory effect of H₂O₂ on oocyte maturation, there was a significant effect at the concentration of 10.0 ng·mL^-1 of MT. (3)GV stage oocytes were incubated with 2′,7′-dichlorofluorescein (DCF-DA) after co-culture of H₂O₂(500 μmol·L^-1) and MT（0.000，0.001，0.010，0.100 ng·mL^-1） ,the increased fluorescence intensity of oocytes incubated with H₂O₂ was significantly decreased by MT treatment(0.100 ng·mL^-1）.(4) There was no significant difference in the groups of 10^-9-10^-3 mol·L^-1 than the control group during two-cell phase (88.2%, 91.4%, 91.8%, 88.8% vs. 88.1%, P>0.05), the rate of four-eight-cell was improved when added 10^-9M of MT (30.5% vs. 23.4%, P>0.05). There was very significant difference among the rates of 10^-7-10^-3 mol·L^-1 than control group(58.8%,73.8%,43.6% vs.23.4%, P<0.05), Blastocyst rates were increased in the higher concentrations 10^-9-10^-5 mol·L^-1 (24.6%,46.6%,49.2% vs.8.0%, P<0.05),but it decreased during 10^-3 mol·L^-1 of MT. Oxidative stress was harmful for oocytes maturation which were protected by MT. The optimum concentration of MT for development of mouse oocytes after parthenogenetic activation was 10^-5 mol·L^-1. As a direct free radical scavenger, MT could become one of the most important conditions for improving oocyte and embryo quality.

To investigate the mechanism of follicular development in the goat, our present study were designed to co-culture small antral follicles with ovarian cortex stromal cells, theca cells and ovarian medullary stromal cells in vitro for 5 d, respectively, and then to measure the change of diameter of follicles, steroid hormone productions, expressions of oocyte secreted factors (gdf9 and bmp15) and inhibitory apoptotic and pro-apoptotic genes. The results showed that the diameter of follicles were increased significantly in co-cultured groups than which cultured alone after 5 d culture (P<0.05); estradiol production increased in small antral follicles (413.95 pg·mL^-1) after co-cultured with ovarian cortical stromal cells for 5 d (P<0.01); progesterone production extremely increased in small antral follicles (11.695 ng·mL^-1) when co-cultured with ovarian medullary stromal cells for 5 d (P<0.01), progesterone production increased in small antral follicles when co-cultured with theca cells for 5 d (P<0.05); expressions of gdf9 and bmp15 mRNA in the oocytes in follicles co-cultured with ovarian stromal cells and theca cells were increased (P<0.01); expressions of inhibitory apoptotic genes in cumulus cells and oocytes in small antral follicles co-cultured increased (P<0.05), and expressions of pro-apoptotic genes in cumulus cells and oocytes in small antral follicles co-cultured decreased (P<0.05). These results indicated that ovarian stromal cells and theca cells could promote growing of small antral follicles, steroid hormone productions, and expressions of oocyte secreted factors (gdf9 and bmp15), and inhibit apoptosis of small antral follicles; especially enhance the capacity of small antral follicles significantly through inhibiting apoptosis after co-cultured with theca cells.

To explore the effects of different densities of feeder layer cells on isolation and culturing of rabbit ES-like cells and select the better culture system. Rabbit blastulas were cultured at different densities(10×10³, 20×10³, and 40×10³·cm^-2) of mouse embryonic fibroblast cell (MEF) as feeder layer, rabbit ES-like cell adherence and growth behavior were observed and express pluripotency markers were detected, such as AKP and Oct-4. The results showed that the attachment rate of blastulas and ICM formation rate at a density of 20×103·cm-2 feeder layer were higher than those at 40×10³·cm^-2 (82.5% vs 80.0%; 67.5% vs 65.7%, respectively), but the two groups were not significantly different (P>0.05). While stem cells cultured at a density of 20×10³·cm^-2 feeder layer were significantly higher than at 10×10³·cm^-2 feeder layer (82.5% vs 55.6%; 67.5% vs 44.4%, respectively) (P<0.05). The cell clone rate of F1、F2 generation of rabbit ES-like cells at a density of 20×10³·cm^-2 feeder layer was significantly higher than other two groups (P<0.05), and the stem cells obtained were up to the 20th passages and expression of AKP and Oct-4 were positive. In conclusion, the MEF feeder layer at a density of 20×10³·cm^-2 may be better suitable for rabbit ES-like cells culture in vitro.

To investigate the function of soluble guanylate cyclase (sGC) in alpaca skin and coat color regulation, differential expression of sGC in skin of brown versus white alpacas was examined using quantitative real-time PCR(qRT-PCR), Western blotting and immunohistochemistry．Expression of sGC mRNA was lower (0.16 fold) in skin samples from brown alpacas relative to expression in skin of white alpacas with significant difference (P<0.01). Using a rabbit polyclonal sGC antibody, an immune reactive band corresponding to sGC was detected by Western blotting analysis in skin samples from white and brown alpacas, showing a weaker signal detected in the samples from brown alpacas with significant difference (P<0.01). The results of immunohistochemistry revealed that sGC was localized in the cytoplasm and intercellular substance of upper hair papilla in hair follicles of alpacas with white hair color, but was localized in ytoplasm and intercellular substance of lower hair bulb and outer root sheath cells in hair follicles of alpacas with brown hair color. Observed differential expression and localization of sGC in skin of white versus brown alpacas suggests a potential role in hair color regulation.

Myostatin gene (MSTN) was regarded as a candidate gene for selection of porcine growth trait. In this study, the SNPs of MSTN gene had been detected and its association with porcine growth had been analyzed based on reports on its gene structure and function to put it as molecular genetic markers in porcine breeding. Using templates of genome DNA from 6 breeds including Landrace, Yorkshire, Duroc×(Landrace×Large White), Tongcheng pig, Wuzhishan pig, Laiwu pig, the SNPs were identified by cloning and sequencing of MSTN gene located in its promoter region, intron1, intron2, exon1, exon2 and 3′UTR. Matrix assisted laser desorption ionization time-of-flight mass spectrometry methed was used to genotype SNPs in MSTN gene in Landrace and Duroc×(Landrace×Large white) two experimental group and the data was assessdzed by SAS software. Total 16 SNPs were screened from 76 individuals of 6 breeds, of which 4 located in the promoter region, 5 located intron1, 7 located in intron2, while no SNPs was discovered in exon1, exon2 and its 3′UTR region. Association analysis of four SNPs (P1、P3 and P4 located in the promoter region; P5 located in intron1) in MSTN gene with growth traits indicated that P4 and P5 were significantly correlated (P<0.05) with growth traits. Both P4 and P5 have the potential application value as molecular marker in porcine breeding

The study aimed to investigate the effects of endothelin-3 (EDN3) on the expression of hair color genes of alpaca. The activity of melanocyte, the production of melanin in melanocytes and the expressions of related genes and proteins including Endothelin receptor B (EDNRB), KIT, Microphthalmia-associtated transcription factor (MITF) and Tyrosinase (TYR) in alpaca melanocytes in cultures with addition of different dose of EDN3（0, 10^-9, 10^-8, 10^-7 mol·L^-1）, were examined by MTT, ultraviolet spectrophotometry, qRT-PCR and Western blotting, respectively. The results showed that the amount of melanocytes was increased with the increasing double- or tri- dendrites; At the addition dose of 10^-8 mol·L^-1 for 72 h after adding EDN3, compared to control group, the proliferation of melanocytes was obvious and the expressions of EDNRB, KIT, MITF and TYR significantly up-regulated at the level of both transcription and translation in melanocytes（P<0.05）. Moreover, the production of melanin in melanocytes significantly increased（P<0.05）. These findings indicate that EDN3 play an important role in regulating melanins production in melanocytes in alpaca.

The objective of this study was to investigate the effects of early weaning on the development of digestive organs of barn feeding lambs. Fifty-five male lambs (Gansu modern breeding sheep group, single lamb) were randomly assigned to 3 treatments with 15 (experimental group) or 25 (control group) each. 25 animals were not weaned during the experiment (control), 15 animals each were weaned at 28(A) or 42 d(B) of age. Supplementary feed were offered at 7 d of age for all the animals. 5 animals from treatments A or B were slaughtered at 0, 7 and 14 d after weaning accompanied by 5 animals from the control. The relative weight of liver and pancreas, compartments of stomach and intestines, and relative volume of compartments of stomach were determined, respectively. The results indicated that the relative weight of liver and pancreas (% live weight) were increased with age, and the range of increase in group B was greater than that in group A. Compared with the weaned day, the relative weight of reticulorumen (% live weight, % stomach weight) 7 days after weaning were increased by 107.28%, 16.22% and 40.39%, 13.24% in group A and B, respectively, 29.04%, 17.48% and 27.10%, 4.26% in control at the corresponding time, respectively. Compared with the weaned days, relative weight of abomasums (% live weight) in group A were increased 25.39% and 7.42% after weaned 7 and 14 d, respectively, but the animals in group B were significantly declined 78.16% and 65.37% at the corresponding day, respectively. The effect of weaning on the relative volume (% gastrointestinal tract capacity) in stomach and every compartments of stomach were significant, and more acceleration appeared in more early weaned animals. There weren’t significant influence on relative weight (% live weight, % intestinal weight) in every compartment of intestine with different weaned days (P>0.05). The results indicated that, 7 days after weaning, the relative weight of forestomach and reticulorumen (% stomach weight) in weaned groups were close to the adult sheep. Under feeding conditions, the supplementary feed were offered at 7 d after birth, the relative weight and volume of reticulorumen fully developed at the 35 or 28 d of age for barn feeding lambs. The early weaning can be implemented at 28 or 35 d of age.

 This experiment was conducted to study the effects of dietary vitamin B₁ level on growth performance, gastrointestinal digestive enzymes activity and TPK1 gene expression of Qingnonghui geese, to determine vitamin B₁ requirement in different weeks. Three hundred and sixty 1-day-old Qingnonghui geese were randomly selected and divided into 6 treatments with 6 replicates per treatment and 10 geese in each replicate. The level of vitamin B₁ in each group were 1.0, 2.8, 4.6, 6.4, 8.2, 10.0 mg·kg^-1 at weeks 0 to 4, and 0.8, 2.6, 4.4, 6.2, 8.0, 9.8 mg·kg^-1 at weeks 5 to 15. The experiment lasted for 15 weeks．The results showed as follows: 1) The relationship between daily weight gain and requirement presented quadratic model in two growth stages, the optimal dietary levels of vitamin B₁ are 5.60 mg·kg^-1 at weeks 0 to 4, and 4.98 mg·kg^-1 at weeks 5 to 15. The relationship between activity of pepsin in glandular stomach contents and requirement presented quadratic model in two growth stages, the optimal dietary levels of vitamin B₁ are 5.48 mg·kg^-1 at weeks 0 to 4, and 6.03 mg·kg^-1 at weeks 5 to 15. The relationship between activity of trypsin and requirement presented quadratic model at weeks 0 to 4, the optimal dietary levels of vitamin B₁ was 5.46 mg·kg^-1. The relationship between activity of trypsin in duodenum contents and requirement presented quadratic model at weeks 0 to 4 and 5 to 15, the optimal dietary levels of vitamin B₁ were 5.36 and 5.41 mg·kg^-1, respectively. 2) At 15 weeks of age, the growth rate of geese and activity of pepsin, trypsin and amylase in pancreas and trypsin and amylase in duodenum contents were positive correlation (P<0.01)，and activity of lipase in pancreas was positive correlation (P<0.05). 3) At 15 weeks of age, 6.2 mg·kg^-1 vitamin B₁ significantly increased the expression of TPK1 gene (P<0.05) and the expression of TPK1 gene and activity of pepsin, lipase in pancreas and amylase in duodenum contents were positive correlation (P<0.01). In conclusion, consideration from the growth performance, the requirement of vitamin B₁ appears to decline with the age. The requirement of vitamin B₁ are 5.60 mg·kg^-1 at weeks 0 to 4，and 4.98 mg·kg^-1 at weeks 5 to 15; Vitamin B₁ effects the expression of TPK1 gene in liver and TPK1 gene regulates the activity of pepsin, lipase in pancreas and amylase in duodenum contents, then regulating the growth performance.

In order to investigate the molecular mechanism affecting the airborne transmission for H9N2 avian influenza virus (AIV), one isolates from Shandong province (SD01) was chose as research subject. The character of its complete nucleotide sequences and phylogenetic tree were analyzed. One recombinant AIV (R01/NASS), NA gene from Guangdong isolate (SS94) without airborne transmissibility and other seven genes from SD01 with this ability, was generated by reverse genetics and its transmissibility was determined in chickens. The results showed that M, NS, NP and HA genes had the highest homology with HK/G9/97, NA, PB1 and PB2 genes had highest homology with HK/Y280/97, and PA gene with SH/F/98. Transmission experiment indicated that the recombinant AIV could transmit by direct contact, but not by aerosol. These results demonstrated that the replacement of NA gene made SD01 virus lost its airborne transmissibility. The results would be useful for further studies on the key amino acids of NA protein, which may relate to the airborne transmission of H9N2 AIVs.

 The Nsp2 protein of porcine reproductive and respiratory syndrome virus (PRRSV) plays an important role in viral replication and pathogenesis. We attempted to analyze the expression and distribution of Nsp2 in Marc-145 cells infected with PRRSV to provide some basis of further investigation of its pathogenesis. The nsp2 gene fragment (covering the PL2 region) was cloned into the prokaryotic expression vector and purified recombinant protein was used as antigen to prepare specific monoclonal antibody. The eukaryotic expression plasmid containing nsp2 gene fragment was transfected into Marc-145 or HEK293 cells. PRRSV infected-Marc-145 cells were collected at different time points. Immunofluoresence and Western blotting were used to analyze the distribution and expression of Nsp2 in cells. A monoclonal hybridoma cell line secreting specific anti-Nsp2 antibody was obtained. The antibody was suitable for immunoblotting and immunofluorescence. Nsp2 was present in the cytosol of Marc-145 or HEK293 cells transfected with the recombinant plasmid. There were two protein bands of about 120 and 50 kDa shown by Western blotting. Expression of Nsp2 in PRRSV-infected Marc-145 cells could be detected initially in the perinuclear cytoplasm at 4 h post-infection, and then throughout the cytoplasm. The major Nsp2 protein at about 120 kDa was seen at 8 h post-infection. Two smaller bands of 70 and 50 kDa were detected at 12 h post-infection. Protein expression increased over time. The expression and cleavage patterns of Nsp2 in PRRSV-infected cells might indicate differential functions of the protein during viral replication and pathogenesis that await further investigation.

To enhance immune response induced by DNA vaccines, porcine reproductive and respiratory syndrome (PRRS) DNA vaccines pCI-ORF5 was adsorbed on the surface of poly(lactide-co-glycolide) (PLGA) microparticles. The microparticles were prepared using a solvent evaporation method and the adsorption amount, in vitro release profiles and in vivo immunogenicity were evaluated. The results indicated that the DNA adsorbed on PLGA microparticles was about 0.9％ in 6 hours, and the release behaviors were influenced by some parameters such as CTAB content, PLGA molecular weight, PLGA concentration, internal aqueous phase volume. The PLGA microparticles with adsorbed DNA induced significantly enhanced humoral and cellular response in comparison to naked DNA in mice. It suggests that PLGA microparticles could be a promising vector for the delivery of DNA vaccines.

In this paper, the action mechanism of BF2-A/B, two analogues of antimicrobial peptide BuforinⅡ, on Staphylococcus aureus membrane had been researched. The results of FACScan analysis implied that BF2-A/B did not induce the influx of PI into the S. aureus cells. The rate of positive cells stained by fluorescent probe after BF2-B treatment was slightly higher than that of BF2-A. These electron micrographs showed that after 20 min of treatment by BF2-A, S. aureus cells still retained the plasma membrane integrality; however, BF2-B could cause some slight leakages of cellular cytoplasmic contents. The results of FACS analysis displayed that both the peptides could penetrate the cells, and BF2-B penetrated the cells more efficiently. The visualization of confocal microscopy proved that FITC-labeled BF2-A and BF2-B penetrated the bacterial cell membrane and accumulated in the cytoplasm of the cell immediately. The results of research demonstrated that BF2-A/B didn’t destroy the cell membrane of G⁺ bacteria, and then exert the antimicrobial activity after influx into cytoplasm. BF2-B slightly disturbed cell membrane causing influx of PI and leakage of cytoplasmic contents during peptide crossing phospholipids bilayer. Meanwhile, the cell-penetrating efficiency of BF2-B was accordingly enhanced, which caused that BF2-B displayed more excellent antimicrobial activity to S. aureus.

The current study was aimed to analyze the association of exon 3 of stearoyl-CoAdesaturase gene (stearoyl-CoA desaturase, SCD) with milk traits in Laoshan dairy goat (Capra hircus). Direct sequencing was applied to identify SNPs in exon 3 and its flanking regions of SCD gene in Laoshan dairy goat population containing 174 samples, and least square method was performed to evaluate the association of polymorphism in SCD with milk traits. Four SNPs have been identified as followed, E315 E/e and E368H/h in exon3, I346 R/r and I355Q/q in in eron3 of SCD gene. The distribution of alleles and genotypes in this group were all under Hardy-Weinberg equilibrium. And the alleles and genotypes distribution of E315 were consistent with that of I355, so the two sites were linked sites. The difference between genotypes EE/QQ and ee/qq was statistically significant for all milk ingredients (P<0.05 or P<0.01).And the difference between genotypes EE/QQ and Ee/Qq was significant for protein rate, milk density (P<0.05). Allele E/Q had positive effects on all milk ingredients, in which the additive effects were highly significant (P<0.01) and the dominant effects were not significant (P>0.05). The difference between genotype hh with genotypes HH and Hh was statistically significant for all milk ingredients (P<0.05 or P<0.01). Meanwhile the allele h had positive effects on all milk ingredients. The additive effects and the dominant effects of allele on all milk ingredients were both highly significant (P<0.01). The milk yield of genotype rr was significantly higher than that of RR (P<0.01). Allele r had positive effect on milk yield, while it had no significant effect on milk ingredients (P>0.05). Then we analyzed the association of polymorphisms in SCD gene with milk traits in Group F and Group P respectively. The difference among genotypes were very low on milk traits in Group F, while that was higher in Group P. Four SNPs have been identified in exon 3 and its flanking regions of SCD gene, E315 E/e, E368H/h I355Q/q and I346 R/r, in which I346 R/r had not yet been found in other domestic dairy goats. Alleles E/h/Q had positive effects on all milk ingredients and allele r had positive effect on milk yield. The effects of SCD gene on milk traits of Laoshan dairy goats mainly be owing to the influence of Group P.

The purpose of this study was to establish Fipronil nanoemulsion formula and to analyse its quality and security. The appropriate oil phase and surfactant were selected according to the drug loading, stability and toxicity of nanoemulsion and the optimum formula was designed using pseudo-ternary phase diagram. The configuration was measured by TEM and the particle size, polydispersity and zeta potential were measured by LPSA. The stability was tested by high speed centrifugation and optic observation. Its security was evaluated in this study by dermal acute toxicity and LD₅₀. Evaluation of its transdermal permeability was measured by utilizing modified Franz diffusion device. The optimum formula of Fipronil nanoemulsion was composed of 1.2% (w/w) Fipronil, 8.0% (w/w) cinnamaldehyde, 32.0% (w/w) EL-40 and 58.8% (w/w) distilled water. The shape of Fipronil nanoemulsion droplet was spherical under TEM and the particle size ranged from 5 to 24 nm, with the average diameter of 11.5 nm. The PDI was 0.218 and the Zata potential was －20.6 mV. It was stable. The security test demonstrated that its dermal acute toxicity test was good and LD₅₀ was 2 626 mg·kg^-1, therefore it was Low-toxic. Its percutaneous penetration was enhanced. The Fipronil nanoemulsion was successfully prepared, it was stable and Low-toxic. Its percutaneous penetration was well.

To reveal the reproductive toxicity mechanism of zearalenone(ZEN) to male animals, the role of LH/hCG receptor and cAMP in zearalenone inhibiting testosterone secretion in mouse Leydig cells has been researched. Primary Leydig cells in vivo were taken to determine the testosterone level (hCG or cAMP stimulated) and cAMP level (hCG stimulated) after exposed to 0, 1, 5, 10, 20 μg·mL^－1 zearalenone for 12 h or to 2.5 μg·mL^－1 for 1, 6, 12, 24 h by ELISA, determined binding activity of LH/hCG receptor by Chemiluminescence Immunoassay (CLIA), and determined LH/hCG protein expression level by Western Blot. The results showed that in hCG environment long time and high dose zearalenone exposure inhibited testosterone secretion extremely significant (P<0.01), in cAMP environment every dosage and time exposure for zearalenone reduced testosterone secretion significant (P<0.05), and the time- or concentration- effect relationship was obvious. Every exposure condition effected neither LH/hCG receptor binding activity nor protein expression obviously (P>0.05), and low concentration and long time zearalenone exposure could increase the intercellular cAMP level significantly (P<0.05). These results indicate that zearalenone can inhibit testosterone secretion through cAMP pathway but not LH/hCG pathway.

 The aim of this study was to investigate the effect and mechanisms of Xijiao Dihuang Decotion（XJDH）on Lipopolysaccharide (LPS) -induced fever in rats. One hundred and twenty rats were randomly allotted into four groups: Control group, LPS group, Aspirin group and XJDH group. There were 30 rats in each group. LPS group, Aspirin group and XJDH group were reproduced by intraperitoneal injection of LPS 100 μg·kg^-1, then Aspirin group and XJDH group were drenched with Aspirin (0.04 g·mL^－1，10 mL·kg^－1 in drug delivery according to body weight) and XJDH (1.6 g·mL^－1，10 μg·kg^－1 in drug delivery according to body weight) respectively；Control group and LPS group were drenched with saline. The basal body temperature was measured before LPS was injected and then 8 h later, 2 h after administration, 6 Hypothalamus samples were collected in each group at the point of 2, 3, 5 and 8 h. IL-1β and PGE₂ were measured. The results showed that, compared with LPS group, the temperature in XJDH group were significantly improved; Compared with the control group, IL-1β of LPS group was significantly increased (P<0.05) at 2 h and 3 h, PGE₂ of LPS group was significantly increased (P<0.05) at 2 h; Compared with LPS group, XJDH significantly lowered the levels of IL-1β and PGE₂ (P<0.05). The above results suggest that XJDH significantly inhibited LPS-induced fever in Rats. The mechanism of initial antipyretic may be related to the inhibition of IL-1β in Hypothalamus, and reduce the release of PGE₂.

This experiment was conducted to study the effect of oviduct epithelial cells co-culture on the development of early embryos, and explored the mechanisms of oviduct epithelial cells co-culture on overcoming the developmental arrest in mouse. Mouse oviduct epithelial cell line was purified and used to co-culture the zygotes, H₂O₂ contents in embryos were measured by DCHFDA, MTT was used to measure the activity of epithelial cells, RT-PCR was applied to test the transcriptions of CAT and GPX genes. Oviduct epithelial cells co-culture can significantly improve the early 2-cell and 4-cell rates (P＜0.05), the blastocyst rate was also increased (P＞0.05). Oviduct epithelial cells co-culture can decrease the H₂O₂ content in early 2-cell embryos (P<0.05). Also there was a deposit of H₂O₂ in the arrested embryos, the rates of typeⅠand Ⅱarrested embryos were decreased（P>0.05），type Ⅲ was increased（P＜0.05）by oviduct epithelial cells co-culture. On the other side, the cellular activity was improved (P＞0.05) when embryos developed to early 2-cell phase, at the same time, transcriptions of CAT and GPX were increased（P>0.05）. Those results indicated that oviduct epithelial cell co-culture can improve the development of embryos by cell-cell contact to decrease the reactive oxygen species content in embryos, overcome developmental arrest and promote embryo development.

The aim of this study was to investigate the distribution of serovars and virulent genes of yak Salmonella from the some areas of the Qinghai-Tibetan pleteau. The serotyping result exhibited that the 31 yak Salmonella isolates were divided into 8 different serovars, S. Dublin (32.26%), S. Enterica (29.03%) and S. Typhimurium (12.90%) were dominant serovars, other are S. Blegdam, S. Onarimon, S. Stanely, S. Orion and S. Newport. In addition, the 14 different virulent genes were detected in 31 yak Salmonella isolates by PCR method. The results showed all isolates carried virulent genes of the pathogenicity island-1 (SPI-1) to SPI-5, and the five serovars yak Salmonella isolates carried the virulence plasmid. It is noteworthy that the S. Blegdam and S. Onarimon were first found to possess the virulence plasmid. Therefore, the high carrying rate of virulence plasmid was occurred in yak Salmonella suggested that the yak Salmonella might have strong pathogenicity, which will provide important information to further study the pathogenicity of yak Salmonella from the Qinghai-Tibetan pleteau.