This study was aimed to clone silent information regulator 2 (SIRT2) gene in Wenshan cattle,detect the expression patterns of SIRT2 gene in different tissues of Wenshan cattle, and investigate the subcellular localization of SIRT2 protein in 293A cell lines.One pair of specific primers was designed in the conserved region which based on the bovine SIRT2 gene sequence in GenBank (accession No.:NM_001113531.1),using cDNA as a template,the SIRT2 gene of Wenshan cattle was cloned for homology and phylogenetic analysis.The expression level of SIRT2 gene in heart,liver,kidney,lung,stomach,colon,muscle and fat of Wenshan cattle was analyzed using GAPDH gene as internal reference gene.The pDsRed-SIRT2 eukaryotic expression vector was constructed and transfected into 293A cell line to observe the subcellular localization of the fusion protein.The results showed that the open reading frame of SIRT2 gene in Wenshan cattle was 1 173 bp,encoded 390 amino acids,the molecular weight was 43.3 ku,the theoretical isoelectric point was 4.985.SIRT2 protein was hydrophilic and negatively charge.Homology analysis indicated that SIRT2 gene sequence of Wenshan cattle was highly homologous to mammals such as buffalo,dolphin and hoof,but the distance from the phascolarctos cinereus tree was long.It was surmised that marsupial mammals were prematurely separated from other mammals during evolution,so the marsupial mammals need to be special considered in the genetic research.Real-time quantitative PCR result showed that SIRT2 gene was expressed in all detected eight tissue samples of Wenshan cattle,the SIRT2 gene expression levels in muscle and liver were significantly higher than those of other tissues (P<0.05).The fusion expression vector pDsRed-SIRT2 was mainly located in the cytoplasm of 293A cell line,which might involve in the operation of some organelles and the transport of intracellular substances,regulate cell homeostasis and provide the necessary energy material during cell propagation.This study provided a theoretical basis for further exploring the fuction of SIRT2 gene in cattle.

This experiment was aimed to study the cloning and sequence analysis of interferon gamma (IFN-γ) gene in Congjiang Xiang pig.The total RNA of liver tissue in Congjiang Xiang pig was extracted and reversely transcribed into cDNA.The encoding region of Congjiang Xiang pig IFN-γ gene (CJ-poIFN-γ) was amplified using specific primers by nested PCR,ligated to pUCm-T vector,and verified by sequencing.Sequence analysis of CJ-poIFN-γ by NCBI,SOPMA,SignalP-4.1,DNAStar and so on.The results showed that the coding region of CJ-poIFN-γ gene was 501 bp,encoding 166 amino acids.The results of nucleotide sequence alignment showed that the homology of CJ-poIFN-γ among Congjiang Xiang pig, Meishan pig,Jianbai pig,Tibetan pig,Chenghua pig,Rongchang pig,Indian pig,Landrace pig and Neijiang pig was 99.4% to 100.0%.Phylogenetic tree analysis showed that CJ-poIFN-γ was closely related to Meishan pig,Jianbai pig,Tibetan pig and Chenghua pig;CJ-poIFN-γ gene coding protein was secretory protein,there was no transmembrane structure,and the first 23 amino acids were signal peptide sequences.The secondary structure of CJ-poIFN-γ gene coding protein was mainly α-helix (50.60%) and random coil (33.14%).The B cell epitopes were mainly located in 62-65,84-87,113-115,144-156 and 162-166 amino acids.The results laid a foundation for further study on biological activity of IFN-γ and speeding up the effective utilization of the resources in Congjiang Xiang pig.

This study was aimed to explore the correlation between the transcription levels of cytokines (IL-6 and IL-17) and the infection of Mycobacterium bovis,and evaluate potential of these cytokines for bovine tuberculosis (bTB) diagnosis.Clinically TB-infected cattle and healthy cattle were screened by the skin tests and IFN-γ release assays.Heparinized blood from each animal was collected and used for isolation of the peripheral blood lymphocytes (PBMC).PBMCs were respectively incubated with bovine tuberculin (PPD-B),avian tuberculin (PPD-A),recombinant protein CFP-10-ESAT-6 (CE),PET or PBS at 37℃ for 6 h,and then the transcription levels of IL-6,IL-17 and IFN-γ mRNA were detected by Real-time PCR.As with PBS,PET could not stimulate the increase of cytokine mRNA level,which indicated the influence of PET contained in CE was negligible.PPD-B,PPD-A or CE significantly increased mRNA levels of IL-17 and IFN-γ in PMBCs from TB-infected cattle (P<0.05), of which PPD-B showed the highest stimulus intensity,while CE exhibited the best stimulus specificity.Under the condition that CE was selected as optimal stimulus,the correlation between IL-17 and respective IFN-γ mRNA levels were observed (spearman r=0.79),and then Real-time PCR assays of IL-17 and IFN-γ were preliminary developed.The detection rate of IL-17-based method on 14 clinical bTB-positive samples was 85.7%,which was higher than 71.4% of IFN-γ.Taken together,these findings supported the IL-17 mRNA level in PBMC was related with bTB infection,and demonstrated that measurement of IL-17 mRNA by Real-time PCR was potential for bTB diagnosis.

The keratin-associated protein 2 (KAP2) gene was cloned from Xinji Fine-wool sheep and Small-tail Han sheep,the KAP2 proteins was analyzed by bioinformatics,and the relationship between KAP2 gene and molecules trait of wool hair was preliminary analyzed in this study.The total RNA was extracted from wool follicles of Xinji Fine-wool sheep and Small-tail Han sheep.The KAP2 gene was cloned by RT-PCR,and the PCR product was cloned into pMD19-T vector,then was transferred to Escherichia coli DH5α competent cells and the requisite clones were filtered,and the recombinant plasmid was extracted.Identification of PCR and double enzyme digestion and sequencing were operated,then the prediction of protein structure was analyzed by bioinformatics.The results showed that the length of KAP2 gene was 463 bp,containing an ORF that was 414 bp and encoded 137 amino acid residues.The comparison of sequencing results showed that compared with the KAP2 gene in Small-tail Han sheep,there was a base mutation from G to A in KAP2 gene of Xinji Fine-wool sheep which was a missense mutation causing the encoded amino acid changed from arginine (Arg) to glutamine (Gln).The molecular weight of KAP2 protein in Xinji Fine-wool sheep and Small-tailed Han sheep were 14.81 and 14.84 ku,and the isoelectric points of KAP2 protein were 9.67 and 9.82,respectively.The KAP2 protein of the two breeds was no obvious differences in physical and chemical properties,which was transmembrane, alkaline and hydrophobic protein.It was predicted that the secondary structure of KAP2 protein was composed of α-helix,extend chain and random coil.The tertiary structure of KAP2 protein in Xinji Fine-wool sheep and Small-tail Han sheep had a different spatial structure that came from α-helix.Therefore,it could be speculated that KAP2 gene might be a differential gene affecting wool quality.The study of KAP2 gene provided a theoretical basis for exploring the molecular inheritance of phenotypic differences between two wool species.

This study was aimed to explore the characteristics of B cell lymphoma 2 related A1 (BCL2A1) gene in Jinchuan yak.BCL2A1 gene was amplified by PCR using Jinchuan yak blood DNA as a template,and the gene sequences and protein structures were analyzed using DNAStar,ExPASy,ABCpred and other bioinformatics softwares.The results showed that the length of BCL2A1 gene was 622 bp,GenBank accession number:MG459158.The open reading frame was 516 bp,which could encode 171 amino acids with molecular weight of 19.46 ku.The higher proportions of amino acids were Val (V) and Lys (K),up to 9.4% and 8.8%,respectively.The theoretical isoelectric point was 4.99.The unstability index was 17.44,with transmembrane helices(Scores>500).The main secondary structure was alpha helix of 60.82%.There was a BCL2 domain,the tertiary structure model had the highest homology with human BCL2A1 (72.79%).BCL2A1 had a B cell potential epitope.Alignment with Bos mutus amino acid sequence showed that there were five amino acids mutations.Phylogenetic relationships revealed that the genetic relationship was the closest between Jinchuan yak and Bos mutus,and the homology was 98.5%.The BCL2A1 gene of Jinchuan yak was cloned successfully,which was highly conserved in mammals.It provided a theoretical evidence for further study on the function of BCL2A1 gene in yak.

From the transcriptome data of ovary using the RNA-seq technology, retinoic acid receptor responder 1 (RARRES1) gene was screened out from the differential expression profile of Xiang pigs.To further reveal the underlying reason for the gene differential expression,the ovarian tissues samples were collected from two groups of Xiang pig with high and low litter sizes.Based on bioinformatics analysis which predicted that the downstream of ATG start codon in exon 1 of RARRES1 gene was rich with CpG sites,specific primers for this region were designed,and the methylation status of RARRES1 gene was tested by bisulfite sequencing PCR method (BSP).The expression level of RARRES1 gene was detected by quantitative Real-time PCR method,and its relationship with methylation level was analyzed.The results showed that the methylation level of RARRES1 gene in high litter size group was higher,and in both of the two groups, there were four CpG sites (CpG_7,CpG_11,CpG_12 and CpG_15) keeping unmethylated state,while the other three sites (CpG_8,CpG_17 and CpG_18) were all modified by methylation.There were four CpG sites were differently modified between the two groups with sites,CpG_4(P>0.05),CpG_9(P<0.05) and CpG_16(P<0.05) were higher and site CpG_6 (P<0.01) to be lower in high litter group than that in low litter size group.And the results of quantitative Real-time PCR showed that the mRNA levels of RARRES1 gene in high litter size group were much higher than that in another group (P<0.05).Besides,Spearman correlation analysis estimated there was a strong positive relationship between the methylation ratio of CpG_9 and CpG_16 and the expression level of RARRES1 gene (R²=0.896,P<0.01).It suggested that the methylation of exon 1 region might have a certain effect on promoting the expression of RARRES1 gene in Xiang pig ovary.

The aim of this experiment was to investigate the expression of myostatin (MSTN) gene in mouse myocardium at different developmental stages.12 healthy mice at different developmental stages were chosen,including young (7 days old),sexual mature (21 to 28 days old), somatic mature (42 to 56 days old) and aged mice (84 days old or older),with three mice per developmental stage.The expression of MSTN gene in mice myocardium and myocardial development were detected by quantitative Real-time PCR,HE staining and immunohistochemistry.The results of quantitative Real-time PCR showed that MSTN gene could express in myocardium tissue of mice at all different developmental stages.And it was the highest in aged mice and the lowest in somatic mature mice.Compared with the aged mice,the expression of MSTN gene in juvenile mice and sexually mature mice was significantly decreased (P<0.05), however,it was extremely significantly decreased in somatic mature mice (P<0.01).The results of HE staining showed that the growth of myocardial nuclei and muscle fibers were differences in different ages.Among them,the nucleus was the most and the muscle fiber arrangement was relatively close in juvenile mice,but the indexes of myocardial development in sexually mature mice,somatic mature mice and aged mice were decreased in turn.Immunohistochemical results showed that MSTN was mainly expressed in the nucleus of myocardium,and the level of its expression in each stage was consistent with the results of quantitative Real-time PCR.

microRNAs (miRNAs) are a class of small non-coding RNAs of 22 nt, extensively exists in a variety of organisms.miRNAs can degrade target mRNA or inhibit their translation through binding with the 3' UTR region of target genes by incompletely base-pairing,which negatively regulate gene expression at the post-transcriptional level,and then been widely involved in the regulation of growth, development, diseases and other biological processes.Skeletal muscle accounts for about 40% of the body weight, which is essential for animals to maintain normal growth and development.miRNAs play important roles in the processes of skeletal muscle development,regeneration and disease through targeting the key factors of different stages.As an important regulatory factor of skeletal muscle diseases, miRNAs have become detection markers and targeted therapeutic drugs of muscle-related diseases.In recent years, with the deepening of miRNAs research, it has been found that the regulation of miRNAs on skeletal muscle become a hot topic in the field of life science.The authors reviewed the advances in regulation of skeletal muscle cells proliferation,differentiation,regeneration and diseases by miRNAs in order to provide a theoretical basis for the treatment of muscle diseases and the improvement of meat quality in the future.

The purpose of the experiment was to compare the energy metabolism of ammoniated maize stalk in sheep by different methods (the direct method and the substitute method).20 4-month-old healthy Dorper rams about 25 kg were chosen and divided into 5 groups with 4 replicates per group and 1 ram per replicate.The rams in direct method group (full ammoniated maize straw group) fed only ammoniated maize stalk, and the substitute groups fed with different ratios of ammoniated maize stalk substitutes in basal diet (0, 20%, 40% and 60%).The in vivo method was used to determine animal digestion metabolism and respiratory calorie.The test period was 60 d including the pre-feeding period of 15 d,the official trial period of 45 d with three phases and 15 d per phase.The results showed that in the substitute method groups,the apparent digestibility of DM,CP and OM of the diets significantly decreased with the increase of the substitution ratio (P<0.05),but all of them were significantly higher than that of the direct method group (P<0.05).The values of DE and ME in the substitute method groups were also significantly higher than those in the direct method group (P<0.05).By comparing the DE and ME among the substitute method groups,the DE and ME was decrease in turn with increase of the substitution ratio.However,in the determination of the digestibility and energy assessment of the ammoniated maize stalk as the raw material,the apparent digestibility of DM and OM,DE and ME in the direct method group were significantly higher than those in 60% replacement group (P<0.05), but there was no significant difference with other substitute groups (P>0.05).In conclusion,when the direct method and the substitute method were used to evaluate the assessment of energy of ammoniated maize stalks, the difference of substitution ratio could make a significant difference to the results.When the energy metabolism of ammoniated maize stalk was determined by the substitute method, the optimum ammoniated maize stalk replacement ratio was 20%.

The aim of this study was to investigate the effects of Enterococcus faecium on the production performance,immune organ indexes and blood lipid metabolism-related indexes in AA broilers,and explore the feasibility of the application of Enterococcus faecium replaced antibiotics in broiler diet and its optimal dosage.600 1-day-old AA male broilers with 50 g body weight were chosen and randomly allocated into 5 groups with 6 replicates per group and 20 AA broilers per replicate in a complete randomized design.The five groups were CON group (basal diet),ANT group (basal diet+0.1% chlortetracycline), LEF group (basal diet+50 mg/kg Enterococcus faecium),MEF group (basal diet+100 mg/kg Enterococcus faecium) and HEF group (basal diet+200 mg/kg Enterococcus faecium).The experiment was divided into two phases with the early stage was 1 to 21 d and the later period was 22 to 42 d.The results showed as follow:①There was no significant difference in the growth performance between experimental groups and CON group (P>0.05).In the whole period,the mortality of AA broiler in MEF and HEF groups was the lowest.②In the later stage of feeding,compared with the CON group,the thymus index of MEF group was significantly increased (P<0.05),while the spleen index had a tendency to increase (0.05 < P < 0.1).③In the early stage, compared with CON and ANT groups,the content of TC in serum of LEF and HEF groups was extremely significantly decreased (P<0.01),and compared with the ANT group,the content of TG in serum of LEF and MEF groups was extremely significantly decreased (P<0.01);Compared with the CON group,the HDL content were extremely significantly increased in MEF and HEF groups in serum (P<0.05), and compared with the ANT group,the LDL content in serum of groups adding Enterococcus faecium were extremely significantly decreased (P<0.01).In the later stage, compared with the CON and ANT groups,the TG content in serum of LEF group was extremely significantly decreased (P<0.01),while HDL content in LEF and MEF groups was extremely significantly increased (P<0.01).It was concluded that Enterococcus faecium would be an ideal feed additive to reduce mortality rate to a certain extent,and promote the development of immune organ and decrease blood lipids.And the optimum supplemental level of Enterococcus faecium was 100 mg/kg under the conditions of this experiment.

This study was conducted to elucidate the effects of transfer time and spraying essential oil on weanling stress of weaned piglets so as to optimize the model of transfer,192 28-day-old Duroc pig×Large White pig×Yorkshire pig crossed weaned piglets with (7.00±0.50) kg body weight were chosen and divided into 4 groups with three repeats per group and 16 piglets per repeat.2×2 orthogonal design was used to discuss the effects of different transfer time (08:00 and 20:00) and the spraying essential oil (spraying or not spraying) on diarrhea rate,mortality,blood biochemical indexes,oxidation indexes and immune indexes of weaned piglets.The results showed that there were no significant difference of serum TP and ALB levels among the experimental groups at 1,8 and 24 h after transfer (P>0.05).The serum GLU of weaned piglets in groups transfered at 20:00 was lower than that transfered at 08:00,and that was lower after sprayed essential oil.The serum COR and MDA level were reduced with the increasing of post-transfer time.The MDA level of groups spraying essential oil were significantly decreased than that not spraying essential oil at 1 and 8 h after transfer (P<0.05),and the COR level was significantly decreased at 24 h after transfer (P<0.05).There were no significant differences of serum IgA,IgM and IgG levels among the experimental groups at 1,8 and 24 h after transfer (P>0.05).There was no significant difference of IL-10 level in groups when transfered at different time,while it was significantly decreased when sprayed essential oil (P<0.05),and that was lowest in group transfered at 20:00 and sprayed essential oil.In conclusion,the weanling stress was lower when piglets transfered in at 20:00 than at 08:00,and spraying essential oil could further relieve stress reaction,it was an ideal model to reduce piglets weaning stress when transfered in the evening and sprayed essential oil.

In order to explore the effect of compound probiotic (Saccharomyces cerevisiae + Bacillus subtilis) on immunity level of early weaned piglets,80 weaned piglets (Duroc pig×Landrace pig×Yorkshine pig) were equally divided into four groups and 20 pigs per group.The pigs in groups Ⅰ,Ⅱ and Ⅲ were fed basal diet with 0.10%,0.20% and 0.30% compound probiotic,respectively,others in control group were fed with basal diet,so as to evaluate the growth performance,blood biochemistry,serum cytokines and intestinal mucosal SIgA levels.The results showed that the final body weight of groups Ⅱ and Ⅲ were extremely significantly higher than group Ⅰ and control group (P<0.01).The average daily feed intake of group Ⅲ was the highest in the experimental groups,which was higher than groups Ⅰ,Ⅱ and control group (P<0.05).The diarrhea rates in control group and group Ⅱ were extremely significantly higher than groups Ⅰ and Ⅲ (P<0.01).The content of lactic dehydrogenase (LDH),alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in the experimental group were higher than that of control group,and the total protein (TP) was lower than that of control group (P>0.05).The content of serum urea nitrogen (BUN) in the experimental groups were significantly higher than that of control group (P<0.05),and the content of aspertate transaminase (AST) in groups Ⅱ and Ⅲ were significantly higher than that of group Ⅰ and control group (P<0.05).At 0 day,the level of IL-6,IL-1β and TNF-α in the experimental groups were not significantly different from that of control group (P>0.05).At 20 days,the level of IL-6 in groups Ⅱ and Ⅲ were extremely significantly higher than that of group Ⅰ and control group (P<0.01),the levels of IL-1β and TNF-α were no significant difference compared with control group (P>0.05).At 40 days,the level of IL-1β in experimental groups were higher than that of control group (P>0.05),the level of IL-6 and TNF-α were extremely significantly higher than that of control group (P<0.01).The level of SIgA of jejunum mucosa,duodenum and ileum mucosa in experimental groups were extremely significantly or significantly higher than that of control group (P<0.01; P<0.05),the level of SIgA of cecum mucosa was lower than control group (P>0.05).It showed that different contents of compound probiotics (Saccharomyces cerevisiae + Bacillus subtilis) could effectively improve the growth performance of weaned piglets,alleviate the stress response and enhance the immune function.

The objective of this study was to evaluate the effects of the diets which used the Gracilaria lemaneiformis to substitute the rapeseed meal on the digestive absorption, immunity and antioxidant performance of juvenile Carassius auratus gibelio,to determine the optimal replacement scope of the Gracilaria lemaneiformis.In this study, 450 tail of uniform juvenile Carassius auratus gibelio were randomly divided into 6 groups with 3 replicates per group and 25 fish per replicate.The fish of the control group were fed with the basic diet without Gracilaria lemaneiformis,the test diets which used the 3% (D1),6% (D2),9% (D3), 12% (D4) and 15%(D5) Gracilaria lemaneiformis to substitute the rapeseed meal were used to feed the experimental fish for 8 weeks,respectively.The protein and fat content of all the diets were equal,and at the end of the experiment,the activities of enzyme involved in digestive absorption, immunity and antioxidant function were determined.The results indicated that compared with the control group, there were no significant differences in the activities of digestive enzymes in the liver of the fish from each group (P<0.05).The activities of the alkaline phosphatase (ALP) and the superoxide dismutase (SOD) in the liver of the fish from D1 group, the activities of the γ-glutamyl-transferase (γ-GT) in the anterior intestine of the fish from D1 and D2 groups were significantly increased (P<0.05),while the activities of the lipase (LPS),ALP and SOD of the fish from D5 group were decreased significantly (P<0.05).The activities of the acid phosphatase (ACP) in the kidney of the fish from D1 to D3 groups, the activities of serum lysozyme of the fish from D2 to D5 groups and the serum total cholesterol (TC) content and the total antioxidant capacities (T-AOC) in the anterior intestine of the fish from D2 and D3 groups were significantly increased (P<0.05),while the serum total protein (TP) content of the fish from D5 group were decreased greatly (P<0.05).The results indicated that a small amount addition of the Gracilaria lemaneiformis (3% to 6%) would improve the digestion,absorption and immune function of the Carassius auratus gibelio to some extent, when the substitute amount of the Gracilaria lemaneiformis in the diet up to 15%,the negative impacts on the digestive and absorption capacities as well as the health status of the fish would appear.

To study the correlation relationship between body size indexes and body weight of Angus cattle and explore the growth regulation,649 growth development records were collected of Angus cattle born from 2012 to 2016 of a Angus ranch in Tianshan of Xinjiang,including body size indexes and body weight records.The SPSS 16.0 software was used to measure correlation relationship between body size indexes and body weight.The results showed that the body size indexes and body weight of Angus cattle gradually increased with the increase of age;The growth rate of each body size indexes was fast before 14 months of age,and then slow down;The growth rate of abdominal circumference and chest circumference were higher than other indexes.The average body length index,body index,chest circumference index and abdominal circumference index of Angus bull were 111.99%,129.79%,145.26% and 16.71%,respectively;And that of Angus cow were 112.15%,132.01%,147.86% and 16.95%,respectively.The correlation relationship between body weight and body height,body length,chest circumference,abdominal circumference and tube circumference were all extremely significant (P<0.01),and there was an extremely significant positive correlation between each two of body size indexes (P<0.01).The correlation coefficient between chest circumference and abdominal circumference was highest,which were 0.948 and 0.939 of Angus bull and cow,respectively.And the correlation coefficient between the abdominal circumference and tube circumference was the lowest which were 0.797 and 0.851 of Angus bull and cow.The results of study could provide data to clear the direction genetic breeding,develop and utilize of germplasm resources of Angus cattle.

The aim of the review was to know well the latest progress of feed additives in beef cattle.The foreign literatures on feed additives in beef cattle breeding recently published were summarized in this paper,which mainly focused on the effects of different types of feed supplements on rumen fermentation,production performance,digestive characteristics and meat quality in beef cattle,and the involved additives included glycerol,antibiotics,minerals,vitamins,microorganisms and lipids.The application of feed additives in beef cattle production was very necessary,and the use method and the use effect were the main points.Diet type and roughage ratio would affect the influence of glycerol,mixed use of antibiotics was better than single use,minerals and vitamins with different forms and different dosage had a role in promoting and enhancing on growth and immunity of beef cattle.Therefore,various factors should be considered in actual production,according to the nutrition requirements of beef cattle to choose the appropriate feed additives type and suitable proportion,only in reasonable application ways,the higher economic benefits would be obtained.The research results were summarized and analyzed in this review,which would provide a theoretical basis for the development of beef cattle industry in China.

This experiment was designed to investigate the effects of different dosage of yeast polysaccharide on rumen fermentation of pre-weaning calves.56 Holstein calves with similar body weight and birthday were selected and allotted randomly to four groups with 14 calves (6 heifers and 8 bulls) each group.Calves in groupⅠ(control group)were fed the basis diet,and groups Ⅱ,Ⅲ and Ⅳ were fed the basis diet supplemented with yeast polysaccharide at the dosage of 1,2 and 3 g/d per head,respectively.The experiment lasted for 60 d.At the age of 20 and 60 days,4 calves were slaughtered in every group.Volatile fatty acid (VFA),pH,ammoniacal nitrogen(NH₃-N) and microbial protein (MCP) contents of rumen liquid were measuered.The results showed as follows:① During the whole growth period,there was no significant difference in rumen fluid pH,butyric acid concentration and acetate propionate ratio among the treatment groups (P>0.05).② At the age of 20 days,the concentration of acetic acid in group Ⅲ was extremely significantly higher than that in control group (P<0.01),the concentration of propionic acid in group Ⅱ was significantly higher than that in control group (P<0.05),and the differences of TVFA concentration among all the treatments were not significant (P>0.05).At the age of 60 days,the acetic acid concentration of group Ⅲ was extremely significantly higher than that in control group (P<0.01),and there was no significant difference for the concentration of propionic acid among the four groups (P>0.05).The TVFA concentration in groups Ⅱ,Ⅲ and Ⅳ were significantly higher than that in control group (P<0.05),and the group Ⅲ had the highest TVFA concentration.③ At the age of 20 days,the concentration of NH₃-N in group Ⅲ was significantly lower than that in group Ⅰ (P<0.05),and the yield of MCP in group Ⅱ was significantly higher than that in other groups (P<0.05).At the age of 60 days,the NH₃-N concentration had no significant difference among the four groups (P>0.05),and the yield of MCP in group Ⅲ was significantly higher than that in other groups (P<0.05).These results suggested that adding 2 g/d per head yeast polysaccharide in calves's diets could decrease ruminal NH₃-N concentration,increase MCP and TVFA concentrations,which was helpful to enhance the utilization of ammonia and protein in rumen and promote the stability of rumen fermentation in calves.In conclusion,It could be suggested that the appropriate adding amount of calves 0 to 60 days old was 2 g/d per head.

In order to study the effect of different seasons on the composition of milk fatty acids in buffalo,720 buffalo milk samples in Guangxi all the year round were selected,the composition and content of milk fatty acids in buffalo were determined by gas chromatography to analyze the seasonal changes of milk fatty acids in buffalo.The results showed that 38 kinds of fatty acids were detected in buffalo milk,except for C13:0,C15:0,C16:0 and C20:4n6,the seasons had significant influence on other fatty acids content (P<0.05).The total content of polyunsaturated fatty acids (PUFA) had no significant difference in the four seasons(P>0.05),the total content of short chain fatty acids (SCFA) in winter was significantly higher than other seasons (P<0.05),and the total content of long chain fatty acids (LCFA) and single unsaturated fatty acids (SUFA) in summer were significantly higher than other seasons (P<0.05),while the total content of medium chain fatty acid (MCFA) and saturated fatty acids (SFA) in summer were significantly lower than other seasons (P<0.05).The total content of omega-6 series fatty acids in summer were significantly higher than other seasons (P<0.05),the total content of omega-3 series fatty acids in spring and autumn were significantly higher than that of in summer and winter (P<0.05).The ratio of omega-6/omega-3 fatty acids was the lowest in spring (4.43),followed by autumn and winter,and the ratio of omega-6/omega-3 fatty acids was the highest in summer (6.32).Therefore,it could be seen that the effect of different seasons on the composition of milk fatty acids in buffalo was significant,the farm manager should improve the diet structure and raise the level of raising and management to optimize the composition of fatty acids.

The experiment was conducted to study the effects of forage canola on the slaughter performance and meat quality of Hu lambs.Two hundred 3-month-old Hu male lambs were equally and randomly divided into two groups.One group was fed on corn silage total mixed ration (control group),and the other was fed with forage canola silage total mixed ration (experimental group).A slaughter experiment was carried out to test the slaughter performance and meat quality after 90 days feeding.The results showed that,compared with the control group,the carcass weight,rib fat depth and loin eye area of lambs in the experimental group had no significant (P>0.05),and they showed a significantly higher liver (P<0.01) and kidney weight(P<0.05).For meat quality,a_{45 min}^* and a_24h^* value decreased extremely significantly (P<0.01),the level of behenic acid (C22:0) increased significantly (P<0.05),while the levels of arachidonic acid (C20:4n6),docosahexenoic acid (C22:6n3) and n-6 polyunsaturated fatty acids decreased significantly (P<0.05).The other indexes of meat quality and fatty acid composition had no significant change (P>0.05).In summary,feeding growing Hu lambs with forage canola silage total mixed ration had no seriously adverse effects on slaughter performance and meat quality,had a similar effect with corn silage,which provided a theoretical basis for the utilization of forage canola.

As a potential immuno regulatory adjuvant,β-1,3/1,6-glucans are commonly found in fungi,yeasts and seaweeds.It consists of a linear skeleton of the β-1,3 key chain as main backbone and a highly branched β-1,6 bond as a side chain.Due to its special molecular bonding and intramolecular hydrogen bonding, it forms a spiral molecular structure.This unique configuration is easily accepted by the immune system and exerts its immunity features.β-1,3/1,6 glucan is the first one that has been found to be immunologically active dextran,creating a new chapter in the application of dextran as an immune enhancer.Studies have shown that β-1,3/1,6-glucan,as a biological immunomo regulatory adjuvant,has a regulatory effect on immune system and the efficiency of vaccination.It has higher biological activity,lower caloric value and other aspects, which can be widely used in the fields of medicine, health food and animal husbandry as a fat substitutes, functional factors and dietary fiber making it a worthy endeavor to research and develop as a functional feed additive.Based on the origin,mechanism and biological activity of β-1,3/1,6-glucan,the production performance and immune function of livestock and poultry was summarized in this paper,and the usage in livestock and poultry diets was analyzed hoping to provide fundamental basis for the application of β-1,3/1,6-glucan in diets of livestock and poultry.

This study investigated the expression of PLIN2 gene in subcutaneous adipose tissue and analyzed the association between PLIN2 gene single nucleotide polymorphism (SNPs) and meat quality traits in Qinchuan cattle.The mRNA expression levels of PLIN2 gene in subcutaneous adipose tissue from 6 to 60 months old Qinchuan cattle was detected by Real-time quantitative PCR.536 healthy Qinchuan cattles aged from 18 to 24 months old were selected to collect blood samples and determine the meat quality traits.The expression of PLIN2 gene in subcutaneous adipose tissue increased from 6 months old and peaked at 18 months old with the decreasing till 60 months old.The results showed that 9 SNPs of PLIN2 gene were identified by PCR amplification and direct sequencing,the intramuscular fat content (IMF) of CT genotype in g.C7919>T site was significantly higher than that of TT and CC genotypes (P<0.05).The back fat thickness (BFT) of CC and CT genotypes in g.C7933>T site were significantly higher than that of TT genotype (P<0.05),the IMF of CT genotype was significantly higher than that of TT and CC genotypes (P<0.05).The IMF of CC genotype in g.G8015>C site was significantly higher than that of GG and GC genotypes (P<0.05).The IMF of TC genotype in g.T8496>C site was significantly higher than that of CC and TT genotypes (P<0.05),the BFT of TT genotype in g.C8578>T site was significantly higher than that of CC and CT genotypes (P<0.05).PLIN2 gene could be considered as a candidate reference for Qinchuan cattle meat traits researching,and provided a certain basis for further breeding.

In recent years,the rapid development of genome editing promotes studies of functional genes associated with economically important traits and applications of molecular marker assisted breeding in livestock and poultry.Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) is a newly developed and highly efficient tool for genome editing.Compared with zinc finger endonuclease (ZFN) and transcription activator-like effector nuclease (TALEN),it is characteristic of simple operation,low cost,highly efficient and wide application,which has been widely used in human cells,Drosophila melanogaster,zebrafish,mice,pig,chicken and plants for gene targeting.The CRISPR/Cas9 is the cutting edge of genome editing and broad application in livestock and poultry breeding.The CRISPR/Cas9 system is an acquired immune system which fights against invasion of exogenous virus or plasmids.It has been modified as efficient genome editing technique that can be directed to knockout,knock-in,or substitution of target genes by single guide RNA (sgRNA) to identify foreign DNA and target it for inactivation by nuclease-mediated cleavage.The chicken represents the first agricultural animal to complete its genome sequenced,which serves as an economically important animal and an ideal animal model in biological and molecular genetics studies.In this review,we summarize the evolutionary history,classification,functional mechanism,its application in chicken genome editing,and off-target effect,which will provide important references for gene function studies,genetic improvement of important economic traits,and molecular directed breeding in chickens.

To explore the differences of population distribution of two structural variations(BOLL-I6-SV285 from the intron 6 of BOLL gene on chromosome 15 and STRA8-I4-SV447 from the intron 4 of STRA8 gene on chromosome 18) between local pig breeds and European ones,the genotypes were detected by PCR method taking four pig breeds as samples,including Congjiang Xiang pig,Jiangkouluobo pig,Rongchang pig and Large White pig breeds.The functional elements in structural variations regions were analyzed using the online softwares of miRBase,UCSC and RegRNA 2.0.The results showed that an insertion of DNA fragment with 285 bp in length was confirmed in the structural variations of BOLL-I6-sv285,the dominant genotypes were DI and DD genotypes in three local pig breeds,and the frequency of allele I in the local pig breeds was higher than that in Large White pigs.Furthermore,Ⅱ genotype of BOLL-I6-sv285 was significantly related with higher litter size of Congjiang Xiang pig (P<0.05).For the structure variation STRA8-I4-SV447,it was an insertion mutation with 447 bp,and DD genotype was the dominant genotype in four pig groups,and the frequency of allele I in Congjiang Xiang pig,Jiangkouluobo pig and Large White pig were higher than that in Rongchang pig.The insertion types (Ⅱ) of STRA8-I4-SV447 was significantly related with lower litter size of Congjiang Xiang pig (P<0.05).This results suggested that BOLL-I6-sv285 and STRA8-I4-sv447 could be taken as candidate sites for the litter size choice in Congjiang Xiang pig population.

To explore the effect of non-genetic factors on main economic traits in Chinese Merino sheep (Xinjiang type),a statistical analysis was made on the identification records of one year old ewe in 19 years from 1992 to 2010.The effect of three non-genetic factors (birth years,groups and birth months) on the six subjective traits (capilli score,wool density score,wool bending score,wool fineness score,body condition score and breed grade score) and four objective traits (wool staple length,evalution weight,clean fleece weight and greasy fleece weight) of the identification records of one year old ewe was studied using the least square analysis of variance.The results showed that birth years and groups had extremely significant effect on the 10 economic traits (P<0.01).Except the wool density score,wool fineness score and breed grade score,birth months had extremely significant effect on the other 7 economic traits (P<0.01).According to the 3 main traits (wool fineness score,wool staple length and greasy fleece weigh),the wool fineness score in 2008 was the highest and significantly higher than that in 2006, 2007 and 2010 (P<0.05);The wool staple length in 1996 was the highest and significantly higher than that in 1994,2002,2004,2006,2007,2008 and 2010 (P<0.05),and had no significant difference with 1995,2003 and 2009 (P>0.05);The greasy fleece weight in 1995 was the highest and significantly higher than that in 1994 and 2009 (P<0.05),and had no significant difference with 1992 (P>0.05).In addition,wool fineness score,wool staple length and greasy fleece weigh in other years were extremely significantly lower than the highest (P<0.01).Except group 2,different groups had advantages.Sheep born in January and February were better than that in March and April.It could be seen that the non-genetic factors of birth years,groups and birth months had significant influence on the main economic traits of Chinese Merino sheep (Xinjiang type).Therefore,these factors should be taken into account in the estimation of genetic parameters and genetic assessment,and it provided more reliable data references and laid theoretical basis for obtaining more comprehensive and accurate breeding value and breeding program.

This study was aimed to explore the feasibility of using intracytoplasmic sperm injection (ICSI) method to produce porcine in vitro fertilization (IVF) eggs and application of porcine ICSI fertilized eggs for cytoplasmic injection to produce transgenic embryos.First of all,we compared the efficiency of embryo development between porcine IVF zygotes and ICSI zygotes,and then applied cudbear staining method to observe the pronuclear formation at different time interval and efficiency produced by porcine ICSI zygotes,finally we injected the EGFP-N1(20 ng/μL) plasmid into the zygotes by ICSI and IVF methods to observe the embryonic development efficiency and transgene efficiency.The results showed that the ICSI fertilized eggs had better embryo development rate (cleavage rate 89.4% and 67.9%,blastocyst rate 36.5% and 16.1%) than IVF group(P<0.05);The pronuclear formation time by ICSI method was 12 to 14 h after sperm injection into the cytoplasm,and the rate of prokaryotic nuclei formation was 54.90%,which was significantly higher than the other 5 experimental groups (P<0.05);There was significant difference in the rate of embryonic cleavage rate (86.2% and 66.3%),blastocyst rate (30.0% and 13.6%) and transgene efficiency (18.5% and 0) between ICSI cytoplasmic injection group and IVF test group (P<0.05).This study laid the foundation for the study of producing transgenic pigs by cytoplasmic injection with ICSI fertilized eggs.

microRNA(miRNA) is small non-coding RNAs in eukaryotes that regulates gene expression by combining the 3'end non-coding sequence of target gene,and plays important roles in many biological processes,including cell growth,differentiation,proliferation and apoptosis.miRNA biosynthesis begins in the nucleus,and is divided into three stages of pri-miRNA,pre-miRNA and mature miRNA.The first and second stages are completed in nucleus,and the third stage is completed in cytoplasm.miRNAs have three characteristics,which are widely expressed in eukaryotic cells with length of 21 to 24 nt and highly conserved sequence.The present results indicate that miRNAs involve in porcine embryonic muscle development,postnatal muscle growth and meat quality traits,precursor adipocyte differentiation and lipid deposition,and immune response,interaction between pathogen and swine.Therefore,understanding the functions of miRNA will help to explore the molecular mechanisms of muscle development,fat metabolism,disease immunity in pigs,and may provide references for pig healthy production.

The placenta is an organ that connects the fetus to the uterine wall to allow nutrient uptake,gas exchange and waste exclusion.During gestation in pig,the function of placenta is one of the most importance factor that influence the litter size,stillbirth and the mortality of pre-weaning.In this review,the authors summarized the process of placental formation and morphological changes during the first trimester of pregnancy,the formation of placental folds in the second trimester,and the changes of the placental folds in the second trimester of pregnancy.We also analyzed the related genes that regulate the establishment and development of porcine placenta,including HYAL,CTSB,CTSL1 and HPSE genes.The review will provide scientific guidance for future studies on the placental efficiency and the sow fertility.

The aim of this study was to know the current quality situation of wool from introduced alpaca in Aksu area of Xinjiang.158 introduced alpaca were selected from Tagelake farm in Aksu area,and fiber samples were collected for the measurement of fiber diameter,fiber length,net wool rate,single fiber strength,raw wool grease and fiber crimpy,and the influences of gender,age and coat color on these fiber indexes were analyzed.The results indicated that the average fiber diameter was 23.36 μm,fiber length 106.14 mm,net wool rate 80.90%,breaking strength 8.04 cN,breaking elongation 40.11%,raw wool grease 2.08% and fiber crimpy 6.70 number/2.5 cm.There were significant differences in fiber length,net wool rate and raw wool grease between genders (P<0.05),significant differences in fiber diameter,length,breaking strength and raw wool grease among different ages (P<0.05),significant differences in fiber diameter,fiber length,fiber crimpy and raw wool grease among different coat colors (P<0.05).In conclusion,the mean fiber diameter and length of alpaca wool in Aksu area were excellent,and gender,age and coat color of alpaca had significant influence on the genetic characteristics of wool fiber.

This study was aimed to clone and carry out bioinformatics analysis on the sequence of glycoprotein (GP) gene of Parabronema skrjabini.RNA was extracted from Parabronema skrjabini and cDNA was obtained by reverse transcription.A pair of specific primers was designed to amplify the coding region of GP gene.The target gene was linked into cloning vector pMD19-T to be sequenced.The antigen epitopes,physical and chemical properties,signal peptide and transmembrane domain of GP gene encoding protein were predicted according to the bioinformatics analysis.The bioinformatic analysis results showed that GP gene contained a 1 149 bp open reading fram (ORF),which encoding a hydrophobic protein 382 amino acids with a predicted theoretical molecular weight of 40.15 ku and the isoelectric point (pI) of 4.37.Amino acid sequence analysis showed that the GP protein was hydrophobin and unstable whose formula was C₁₇₆₀H₂₈₇₈N₄₅₈O₅₉₀S₁₇₆₀,the grand average of hydropathicity (GRAVY) was 0.032,and the coefficient of instability was 42.43.The protein was absence of signal peptide cleavage sites and the phosporylation site located in serine,threonine and tyrsine residue.The secondary structure of GP was mainly composed of alpha-helix and random curl,consistent with the results of tertiary structure prediction.Antigen epitopes prediction showed that GP protein might have six B-cell epitopes and eight T-cell epitopes.The GP antigen had promise as a candidate for immune diagnostics and a vaccine against Parabronema skrjabini.The GP gene of Parabronema skrjabini was cloned successfully and the structure and antigen epitopes of its coding protein were predicted by bioinformation software.This research would provide the theoretical basis for establishment of iELISA diagnostic method and development of DNA vaccine.

To select the lactic acid bacteria strains that could be used to prevent and control the metritis in dairy cows,healthy dairy cows 30 to 50 d postpartum were selected to collect the secretions of the cervix,and the lactic acid bacteria were screened by MRS selective medium.The purified strains were subjected to microscopic examination,and the suspected strains with the typical morphology of Lactococcus lactis or Lactobacillus were biochemically identified.The genomic DNA of the isolated strains was extracted,and the 16S rDNA sequence was amplified and sequenced.The sequence of the 16S rDNA sequences was aligned with the NCBI nucleic acid database to identify the genus of the isolates.Antibacterial activity of isolated strains against pathogenic Staphylococcus aureus and Escherichia coli was evaluated using agar diffusion method.The adhesion activity of the isolated strains to goat epithelial cells was also tested.As a result,13 strains of lactic acid bacteria were obtained by staining microscopic examination,biochemical identification and 16S rDNA sequencing.Among them,5 strains had strong antibacterial activity,6 strains had strong ability of adhering epithelial cells,strains of No.7,No.12 and No.23 both had good antibacterial activity and adhesion of epithelial cells.In summary,the experiment established a selected method for probiotic lactic acid bacteria in healthy cow's cervix.3 strains of lactic acid bacteria with good probiotic properties were obtained,which provided the basic materials for the preparation of probiotics and was of great significance for the prevention and treatment of dairy cows.

In order to characterize the VP1 gene of budgerigar fledgling disease polyomavirus (BFPyV) from Melopsittacus undulates (designated as FJ-2016 strain),specific primers were designed according to the VP1 gene of BFPyV retrieved from GenBank.The full-length sequence of VP1 gene of FJ-2016 strain was amplified by PCR.The target fragment was recovered,cloned and sequenced.The results demonstrated that the length of VP1 gene was 1 032 bp,coding 343 amino acids.The VP1 protein theoretical pI,instability index,aliphatic index and grand average of hydropathicity was 5.77,40.91(means unstable protein),74.72 and -0.366,respectively.The sequences were submitted to the GenBank,the accession No. was MG148345.Nucleotides homology of the VP1 gene of BFPyV isolates were above 99.1% with each other.The VP1 gene nucleotides comparison indicated that the VP1 gene was very conserved among different time,regions and species.Phylogenetic tree based on the VP1 gene showed that BFPyV isolates with different time and regions shared closer relationship with each other,which also could be divided into two genetic clades (Clade 1 and Clade 2).The Melopsittacus undulates origin BFPyV could be found in the two genetic clades,these data indicated that Melopsittacus undulates origin BFPyV shared no significant phylogenetic evolution relationship with the time and regions.In conclusion,this study provided evidence of budgerigar fledgling disease polyomavirus circulating in Fujian,which enriched the BFPyV molecular epidemiology data in China.

To analyze the genetic variation of porcine epidemic diarrhea virus (PEDV),the piglet diarrhea samples from Zhejiang province during 2015 to 2016 were detected by Real-time RT-PCR.Two pairs of primers were designed and the S1 gene of 16 PEDV positive samples from different regions were amplified by RT-PCR,cloned and sequenced.The sequence of S1 gene was analyzed by biological information software.The results showed that 48 samples were positive for PEDV.Homologous analysis showed that the S1 gene of 16 PEDV strains shared 93.1% to 99.8% nucleotide homology and 92.4% to 99.7% amino acid homology.The S1 gene of 16 PEDV strains shared 92.3% to 95.7% nucleotide homology and 90.7% to 95.7% amino acid homology with vaccine strain CV777.Compared to vaccine strain CV777,15 nucleotides were inserted and 6 nucleotides were absent in the S1 gene of 15 epidemic strains.The phylogenetic tree based on sequences of S1 gene suggested that 15 PEDV strains had a close relationship with the genotype Ⅱ PEDV,nucleotide and amino acid homologous were all more than 96.6%.Compared with the early separation of CV777 and LZC strains,nucleotide and amino acid homologous were all less than 93.4%.However,strain ZJ16NB6 had a close relationship with the S-INDEL-like strain,nucleotide and amino acid homologous were all 98.4% to 99.5%.The results indicated that PEDV infection was the main pathogen of piglets diarrhea in Zhejiang province.The genotype Ⅱ and S-INDEL-like PEDV strain existed in Zhejiang province,but mainly prevailing the genotype Ⅱ PEDV strains.

In order to express Bc48 gene of Babesia caballi from Xinjiang Yili,and prepare its polyclonal antibody,a pair of specific primers was designed according to Bc48 gene sequence of Babesia caballi in GenBank.The genomic DNA was extracted from Babesia caballi,and Bc48 gene was cloned into pET-28a(+) expression vector.The positive plasmid was transformed to Escherichia coli BL21(DE3).After IPTG induction,the product was analyzed by SDS-PAGE,six weeks old female BALB/c mice were immunized with purified Bc48 protein to prepare polyclonal antibodies.Meanwhile Bc48 gene was cloned into eukaryotic expression vector pCMV-N-flag.The positive plasmid was transformed to Escherichia coli DH5α,eukaryotic expression of pCMV-N-flag-Bc48 plasmid was transfected into 293T cells.The results showed that the recombinant protein with 15 ku was obtained,which was consistent with the expected protein size;Western blotting analysis showed that polyclonal antibodies could specifically identify the corresponded antigens;ELISA analysis showed that the antibodies had high titer (1:128 000);And eukaryotic expression plasmids expressed Bc48 protein in 293T cells.This test could lay the foundation for further study on the functional genes and establish quick detection method of Babesia caballi.It had important significance in the study of strain taxonomy and the development of candidate vaccine.

In order to investigate the control effect of Artemisia annua powders on chicken coccidian,90 healthy yellow feather broilers were selected and divided into 6 groups.Except the blank control group,other chickens were infected with Eimeria tenella (E.tenella),with 6×10⁴ sporulated oocysts,and each test group began to use drugs on the day before the vaccination,until to the end of the test.By recording the indexs of each test group,including their macroscopical lesion,histopathological examination,relative weight-growth rate,lesion scores of pathological changes of cecum,lesion scores of bloody stool,the number of oocysts (OPG),per gram of feces,oocyst score and anticoccidial index (ACI),the thesis made attempts to evaluate anticoccidia effects.The results revealed that the ACI of blank control group,infection control group,drug control group and low,middle and high dose groups of Artemisia annua powders were 200.00,72.23,157.19,82.89,125.32 and 137.06,respectively.Compared with infection control group,the macroscopical lesion,histopathological examination of drug control group and drug supplied groups of Artemisia annua powders were relieved.Artemisia annua powders could reduce sick chicken's cecum swelling and bleeding and other symptoms,and they were in much better spirits than infection control group.Compared with the infection control group,the average weight gain of each drug supply group were all increased,and their cecal lesion scores,oocyst score and bloody stools decreased.The results showed that Artemisia annua powders could alleviate pathological symptoms and tissue lesions infected by Eimeria tenella of chicken cecum,and reduce the amount of feces in the oocysts.The higher the concentration of administration,the better the anticoccidial effect,which was dose-dependent.

In order to study hydrogen-rich saline protects effects against liver ischemia-reperfusion injury and hepatectomy by inhibiting endoplasmic reticulum stress in miniature pig,18 3 to 4 months old and 20 to 30 kg body weight healthy miniature pigs were chosen and randomly divided into three groups:Sham group,model group and HRS group.Sham group only flipped the liver and maintained pneumoperitoneum for 3 h.Laparoscopic technique was employed to establish the model of hepatic ischemia-reperfusion combined with partial hepatectomy in model group.The surgical model was established in HRS group,and 10 mL/kg HRS was injected into the portal vein at 10 min before per-fusion and 1,2,3 d after surgery.Liver tissue samples were collected before operation,immediately after reperfusion,surgery,1 d after surgery and 3 d after surgery.HE staining and the mRNA expression of ERS-related parameters (PERK,IRE1,ATF6, GRP78,ATF4 and CHOP) in the liver were detected.The results showed that pathological changes of liver tissue in model group and HRS group were more serious than that in sham operation group,and ERS-related parameters mRNA level were increased in the model group and HRS group when compared with the sham group.In addition,the liver pathological damage in HRS group was significantly lighter than that in the model group,and all ERS-related parameters of mRNA levels were decreased in HRS group compared with the model group.Those results indicated that ischemia-reperfusion could induce liver ERS and injury,HRS could protect the liver from IRI by inhibiting ERS.

This study was aimed to investigate the resistance of Enterococcus to florfenicol in pig farms and analyze the florfenicol resistance genes.Also,the gene environments of florfenicol resistant gene fexA in Enterococcus were determined to identify the underlying transmission mechanism.Fifty strains of Enterococcus isolated from a pig farm in Sichuan province were used as the research materials to perform the drug susceptibility test of florfenicol.The florfenicol resistance genes cfr,fexB,fexA,floR and estDL136 were detected by PCR.The information of gene environment of fexA gene was obtained by TAIL-PCR and further analyzed.In addition,the presence of cyclized structure in the sequence was verified by PCR.Meanwhile,the genetic environment of 20 fexA-positive isolates was confirmed by cross-PCR.The results showed that among the 50 strains of Enterococcus,34 were resistant to florfenicol (MIC ≥ 16 mg/L),with a resistant rate of 68%.PCR results showed that 20 strains contained fexA gene,28 strains contained fexB gene,and 14 strains contained both of the two genes.Besides,TAIL-PCR and sequencing showed fexA gene in isolated strain DKC5 was located in the 12 945 bp Tn554 transposon.In particular,the Tn554 transposon could form a cyclized structure and its repeating sequence could also form a local cyclized structure containing 2 395 bp.The resistance rate of Enterococcus from swine to florfenicol was high,and was mainly mediated by fexA and fexB genes.Specifically,fexA gene was located in the Tn554 structure.It was predicted that fexA gene was inserted into DKC5 strain genome sequence by two insertions,which provided a genetic basis for the horizontal transmission of fexA gene.

This study was aimed to determine the optimal proliferation conditions for culturing of H9N2 subtype swine influenza virus(SIV) in mouse pulmonary microvascular endothelial cell (PMVEC).The PMVECs were defrosted,recovered and cultured,then the morphological changes of PMVECs were observed and the HA titer of H9N2 subtype SIV of the cell culture supernate was determined by hemagglutination test after action with different concentrations of TPCK-trypsin maintenance media (0.1,0.2,0.3,0.4,0.6,0.8 and 1.0 μg/mL),different doses of H9N2 subtype SIV (1:10,1:100,1:1 000,1:10 000,1:100 000,1:1 000 000 and 1:10 000 000) and different viral adsorption time (0.5,1.0,2.0 and 3.0 h) on single layer of PMVECs.When the dose of TPCK-trypsin was lower than 0.6 μg/mL,there was no effect on morphology structure of PMVEC uninfected with H9N2 subtype SIV.However,the PMVEC began to swell,round and exfoliate with the increase of the TPCK-trypsin concentration;PMVECs were infected with different dose of H9N2 subtype SIV diluted with 0.6 μg/mL TPCK-trypsin culture media,the viral titer were 4.6log2 and 6.4log2 on 48 and 72 h in 0.3 μg/mL cell culture maintenance medium and the dose of 10^-2 H9N2 subtype SIV;Meanwhile,the H9N2 subtype SIV titer was reached to peak value on condition of 2 h adsorption time and vibration 20 s after adsorption 1 h.When the TPCK-trypsin final concentration was 0.3 μg/mL,H9N2 subtype SIV dose of 10^-2,and 2 h viral adsorption and vibration 20 s in the middle of adsorption time,the H9N2 swine influenza virus had optimal proliferation in PMVEC cell,the viral titer was 6.8log2.

This study was conducted to establish the intestinal injury model of porcine epidemic diarrhea virus (PEDV) infection in neonatal piglets.Sixteen crossbred healthy piglets (Ducoc×Landrace×Yorkshire,7-day-old neonatal pigs) were randomly allocated to control and PEDV groups.During a 10-day trial,all the pigs were fed the basal diet.On the 7th day,the infected pigs were orally administrated with 10^4.5TCID₅₀ of PEDV per pig,while the control pigs were given equal amount of sterile saline.On the 10th day,all pigs were orally gavaged with D-xylose (0.1 g/(kg·BW)).One hour later,blood was collected from jugular vein,and then all pigs were killed to obtain the small intestines.The average daily weight gain (ADG),diarrhea rate (DR),intestinal morphological structure,mucosal injury correlated gene mRNA level were measured.The results showed that:①PEDV infection increased the incidence of diarrhea (P<0.05),while reduced ADG (P<0.01);②PEDV infection decreased the plasma D-xylose content,villus height in the jejunum and ileum,the ratio of villus height to crypt depth in the duodenum,jejunum and ileum (P<0.01),and increased crypt depth in the duodenum and jejunum(P<0.05);③PEDV infection up-regulated the mRNA level of PEDV M gene in the jejunum (P<0.01),and down-regulated mRNA levels of villin and i-FABP in the jejunum (P<0.01).In conclusion,the intestinal injury model was successfully established with PEDV infection in neonatal piglets.

Sulfonamides(SAs) are widely used in the prevention and treatment of foodborne animal diseases,and also for the treatment of human diseases.The abuse of sulfonamides can lead to a large number of residues in food and the environment,and ultimately enter into human body,causing damage of human health.The unreasonable use of SAs first leads to environmental hazards and further harms people's health,especially with neurotoxicity that induced host behavioral changes.This article summarized the current status of environmental and food contamination by SAs abuse,and its general damage such as blood system damage,liver and kidney toxicity.Emphasis is placed on the effects of SAs exposure on host psycho-behavioral changes including anxiety,depression and cognitive impairment.In addition,we discussed the related mechanisms such as sepiapterin reductase,mTOR signal and carbonic anhydrase.