Exogenously acquired 16S rRNA methyltransferases (16S-RMTases) genes, which mediate high-level resistance to a variety of aminoglycosides, have been widely distributed in gram-negative bacteria. 16S-RMTases can add the methyl of S-adenosyl-L-methionine (SAM) to the specific nucleotides at the A-site of 16S rRNA, and thus interferes with aminoglycosides binding to the target site. Genes encoding 16S-RMTases are usually mediated by mobile genetic elements such as transposons and further embedded into transferable plasmids or chromosomes, which will contribute to the rapid worldwide dissemination of the resistance genes. More worryingly, genes encoding 16S-RMTases are often associated with other antimicrobial resistance genes such as bla_NDM-1, bla_CTX-M, and qnrB1, which mediate multidrug-resistance against β-lactams and fluoroquinolones. Multidrug-resistant bacteria with 16S-RMTases recently have become a more serious health threat. Similar exponents have been reported across continents, at least in 30 countries or regions. The worldwide spread of 16S-RMTases is becoming a serious global public health concern.

The phenomenon of transmission ratio distortion (TRD) is commonly observed in many organisms, and the purpose of this study is to excavate isolated porcine genomic marker sites and explore their potential genetic mechanisms in a large population with high density microarray to determine genotype. In this study, 60K Illumina Porcine SNP chip was used to genotype 1 020 F2 resource families (Duroc×Erhualian intercross F0-F2 populations). The transmission ratio distortion signal was detected at a single site by TRDscan (BF>100) and TDT (P<0.01), and the function of genes within 100 kb window near the significant signal site shared by the two were analyzed. In addition, a software package for haplotype typing PHASEBOOK was used to analyze the TRD region on paternal and maternal gametes, and multi-loci linkage analysis was utilized to search for potential QTLs within the region. The results showed that:1) In TRD analysis of single site, 44 significant TRD sites were identified and 23 related genes were screened; 27 and 35 significant TRD loci were identified by analyzing paternal and maternal specific TRD effects, among them, there were annotated functional genes near 100 kb of 11 and 25 loci, respectively. 2) Based on the TRD results of haplotype multi-site linkage, the significant paternal TRD sites were located on chromosome 5 and 13, and functionally related QTLs were searched in this TRD region, then 3 QTLs were found to be related to reproductive traits (number of mummies, number of live litters, and number of corpus luteum); The significant maternal TRD regions were located on chromosome 4, 6 and 12, combined with the known QTL database of pigs, 5 QTLs related to reproductive traits were found. The study used large-scale pig family data to systematically identify the TRD sites of pig genomes, which will provide a certain reference for analyzing the TRD phenomenon in pigs and further exploring its biological mechanism.

As a transcription factor, ZBED6 gene can bind to IGF2 to regulate muscle growth and development. But its role in the growth and development of the spleen is unclear. RNA-seq sequencing technology was used to compare the spleen tissue transcription of ZBED6 gene knockout Bama Xiang pigs (ZBED6-KO) and wild-type Bama Xiang pigs (WT) at the same age, so as to explore the effects of ZBED6 gene on spleen tissue development of Bama Xiang pigs ZBED6 knockout. The t-test was used to analyze the phenotypic differences of spleen tissue, and the gene expression of IGF2 that a target gene directly regulated by ZBED6 transcription factors between ZBED6-KO pigs and WT pigs. The total RNA from the spleen tissues of ZBED6 knockout group and wild-type group of Bama Xiang pigs was extracted, and RNA-seq analysis was performed on the Illumina Hiseq 2500 platform. Using Sus scrofa11.1 as reference genome, the differentially expressed genes in spleen tissues of ZBED6-KO and WT Bama Xiang pigs were screened by the standard process of transcriptome analysis. Using DAVID online website to analyze GO and KEGG enrichment analysis of differentially expressed genes. Seven differentially expressed genes were randomly selected to verify the accuracy and reliability of the sequencing results by the RT-qPCR technique. Compared with WT Bama Xiang pigs, the spleen weight and IGF2 gene expression of ZBED6-KO pigs were significantly increased (P<0.05), indicating that ZBED6 gene knockout could promote the growth and development of spleen tissue of Bama Xiang pigs. The sequencing results showed that at least 4G of data was obtained from each sample, and the ratio of Clean Ratio to Q30 of each sample was more than 90%, and more than 83.94% of the reads could be mapped with the pig reference genome, which indicating that the sequencing data were true and reliable. A total of 161 differentially expressed genes were screened by transcriptome analysis, including 90 up-regulated genes and 71 down-regulated genes. Hierarchical cluster analysis of differentially expressed genes showed that the expression patterns of 3 individuals (spleen1, spleen3, spleen6) of ZBED6-KO pigs were similar, and the expression patterns of 3 individuals (spleen2, spleen4, spleen5) of WT were similar, which further proved that the sequencing data were accurate. In GO and KEGG enrichment analysis, 10 significant GO terms and 5 significant pathways were enriched, in which 2 pathways were related to muscle development. The expression patterns of 7 differentially expressed genes were randomly detected by real-time fluorescent quantative PCR experiments consistent with the results of RNA-seq analysis, which confirmed the reliability of sequencing data. Using the Bama Xiang pig as a model, the RNA-seq technology was used to study the effect of ZBED6 gene knockout on the spleen development of domestic pigs, which provided a basis for mining more functions of the ZBED6 gene.

Phenotype and genomic information were used to calculate inbreeding coefficient and the effective population size in Beijing You chicken conserved population, which could evaluate its conservation status. In this study, 40 individuals from Beijing You chicken breeding population in the national Beijing You chicken breeding farm, were used to collect phenotypic information in 2019. The genomic SNP information was used to evaluate the conservation status of Beijing You chicken. The inbreeding coefficients based on ROH (F_ROH), homozygous genotype (F_HOM) and the correlation between joint gametes (F_UNI) were calculated by PLINK. The G matrix constructed by genomic relationship was used to calculate the inbreeding coefficient (F_GRM) through GCTA and R softwares. The SNeP software was used to estimate the effective population size of the historical generation of Beijing You chicken; The NeEstimator software was used to estimate the effective population size of the current generation based on the linkage disequilibrium method. Correlation analysis of inbreeding coefficients among F_ROH, F_HOM, F_GRM and F_UNI was conducted by R-statistics software with the "PerformanceAnalytics" packages. The results showed that over the 40 years from 1979 to 2019, the typical external features including phoenix crest, shin feathers and five toes, were obvious and the percentage of phenotypes in the Beijing You chicken conservation population was stable. And the effective population size of the conserved population gradually decreased from 595 before 98 generations to 176 before 13 generations. And we found that the F_ROH of 0.079 8 for the Beijing You chicken random mating conserved population in 2019 was significantly correlated with F_GRM (P<0.01) with a correlation coefficient of 0.45. Besides, there were also high linear correlations between F_HOM and F_GRM, F_HOM and F_UNI, F_GRM and F_UNI. The inbreeding coefficient of Beijing You chicken has increased slowly in the 40 years from 1979 to 2019, and the conservation work of random mating conserved population in the national Beijing You chicken breeding farm is very effective. Based on the present results, it is suggested that a certain number of individuals from the random mating conserved population of Beijing You chicken should be randomly selected each year for whole genome sequencing, which is conducive to dynamic monitoring the conserved status so that the conserved work program can be adjusted at any time.

This experiment aimed to excavate the effective regions and key genes related to meat quality traits in fast-growing yellow-feather meat-type chickens. In this experiment, 1 923 fast-growing yellow-feather meat-type chickens were slaughtered at 56 days of age to measure carcass and meat quality traits, and genotyped with the customized chicken 55K SNP array. The genetic parameters for carcass and meat quality traits were estimated using the traditional best linear unbiased prediction (BLUP) and genomic best linear unbiased prediction (GBLUP) methods. The key QTL regions and genes were detected using genome-wide association study (GWAS). The results showed that the estimated heritability of pH, meat color L_{24 h}^* as a member of the solute vector family. In addition, the results showed that two haplotypes on chromosome 5 had extremely significant effects on pH and meat color traits. These results lay an important foundation for the optimization of genetic selection scheme and the development of molecular breeding technology for meat quality of yellow-feather meat-type chickens.

The aim of this study was to investigate the gene expression in AMP-activated protein kinase (AMPK) signaling pathway and fatty acid composition in the liver of Muscovy duck at different egg-laying stages, so as to illustrate the mechanism of lipid metabolism in response to egg-laying. Fifteen female Muscovy ducks were selected at pre-laying (22 weeks), early laying (30 weeks), laying (40 weeks) and post-laying (60 weeks) stages, respectively. Serum lipid levels were determined by automatic biochemical analyzer. Liver histological structure was observed by hematoxylin-eosin (HE) staining and Oil Red O staining, gene expression in AMPK pathway was determined by quantitative real-time PCR (qRT-PCR), and fatty acid composition was measured by gas chromatography-mass spectrometry (GC-MS). The results showed that the levels of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), triglyceride (TG) and very low density lipoprotein cholesterol (VLDL-C) were significantly higher at 40 weeks than those at 22, 30 and 60 weeks (P<0.05). The levels of high density lipoprotein cholesterol (HDL-C) at 30 and 40 weeks were significantly lower than those at 22 and 60 weeks (P<0.05). Liver sections stained by HE and Oil Red O showed that the reticular formation was intact at 22 weeks, and lipid deposition significantly increased at 40 and 60 weeks (P<0.05). AMPKα1 was in a low expression level at 22, 30, 40 and 60 weeks, and was significantly lower than the expression of carnitine palmitoyltransferase-1 (CPT1) and fatty acid synthase (FAS) at different egg-laying stages(P<0.05). FAS expressed in a significantly high level at 22, 40 and 60 weeks (P<0.05). The expression levels of hydroxy-methylglutaryl coenzyme A reductase (HMGR), hepatocyte nuclear factor 4α (HNF4α), acetyl-CoA carboxylase 1 (ACC1) and sterol regulatory element binding protein 1 (SREBP1c) at 40 weeks were significantly higher than those at 22 and 30 weeks (P<0.05). Liver saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) were mainly composed of C16:0, C18:0, C18:1 and C20:2 n-6, accounted for 32%, 16%, 30% and 9% of the total fatty acids, respectively. The contents of C14:0 and C16:0 at 40 weeks were significantly higher than those at 22 weeks(P<0.05). The contents of C24:0, C20:2 n-6 and ΣPUFA at 60 weeks were significantly higher than those at 22 and 40 weeks (P<0.05). In conclusion, the liver synthesized large amount of long-chain fatty acids by up-regulating the expression of lipid synthesis genes, including FAS,during egg-laying. The synthesized lipids were deposited in liver and transported into serum thus increased the serum lipid level during laying.

The aim of this study was to investigate the effects of 5-Aza-2'-deoxycytidine (5-Aza-dC) on the proliferation of bovine myoblasts, promoter methylation and mRNA expression of myogenic differentiation 1 (MyoD1). In this study, the Guanling cattle myoblasts cryopreserved in the early stage were recovered and cultured. After they had grown to the logarithmic growth phase, the bovine myoblasts were treated by different concentrations of 5-Aza-dC. The flow cytometry was used to detect cell apoptosis and cycle. The methylation level of MyoD1 promoter was detected by high-throughput detection methods, the expression level of MyoD1 and related genes were detected by qRT-PCR. The results showed that 0.1 μmol·L^-1 5-Aza-dC was the optimal concentration, and the expression of anti-apoptotic factor Bcl was significantly decreased (P<0.01), the expression of pro-apoptotic factor Bax was significantly increased (P<0.01), and the expression of pro-apoptotic factor Caspase-9 was significantly increased (P<0.05); The expression of Cyclin A2 was significantly increased (P<0.05), but the expression of Cyclin B1 and Cyclin D were not significantly affected. The MyoD1 promoter methylation level in blank group and experimental group was detected, and the MyoD1 promoter methylation level in experimental group was significantly lower than that in blank group (P<0.01), while the mRNA expression level was significantly higher in experimental group than that in blank group (P<0.01). In summary, 5-Aza-dC can regulate the proliferation and apoptosis of Guanling cattle myoblasts by changing the expressions of Caspase-9, Bcl, Bax, Cyclin A2 and other genes, and can effectively reduce the methylation level of MyoD1 gene promoter (P<0.01), and significantly increase its mRNA expression (P<0.01). Low concentration of 5-Aza-dC can promote cell apoptosis and regulate MyoD1 methylation level to regulate the expression of MyoD1 in Guanling cattle. At the same time, it is speculated that the methylation level of the MyoD1 gene promoter can affect the growth and development of Guanling cattle myoblasts, which can provide a theoretical reference for screening genetic markers to assist the improvement of Guanling cattle.

The objective of this study was to obtain the coding sequence (CDS) of yak StAR gene, conduct bioinformatics analysis and investigate its mRNA expression characteristics in different tissues. Yak samples were collected from local slaughter house, including heart, liver, spleen, lung, kidney, ovary, oviduct and uterus of adult female yaks (n=5), ovary of yaks at different ages (fetal, 1-year-old and 2-years-old) (n=3), ovary of yaks during different periods of estrous cycles (follicular phase and luteal phase) (n=3), the luteal phase ovary of cattle (n=3). Granulosa cells of yaks were cryopreserved previously. StAR gene was cloned using yak ovarian cDNA as template during luteal phase by reverse transcriptase-polymerase chain reaction (PCR) and its bioinformatics properties were analyzed by bioinformatics software such as MEGA7.0 and ExPASy-ProtParam etc. The tissue expression characteristics of yak StAR gene were detected by quantitative real-time PCR. The results showed that the CDS of yak StAR gene was 858 bp, encoding 285 amino acids. StAR protein was positively charged and belonged to alkaline hydrophilic stable protein, which had no transmembrane structure and signal peptide. It mainly existed in cytoplasm and mitochondria. StAR gene was highly conserved between different species, which accorded with the law of species evolution. The expression level of yak StAR gene was the highest in ovary (P<0.01). The expression level of StAR gene in the ovary of 2-years-old was significantly higher than that of fetal and 1-year-old (P<0.01). Its expression in yak ovary during luteal phase was significantly higher than that during follicular phase (P<0.01), and was significantly higher in cattle ovary than in yak ovary during luteal phase(P<0.01). During the in vitro culture (IVC) of granulosa cells, the expression of StAR gene increased gradually and reached the peak level at 24 h IVC (P<0.01), and then significantly decreased. The results showed that StAR gene was relatively conservative in the course of animal evolution. Its expression level was greatest in the ovary of yak, and changing with age- and estrous cycle-specific characteristics, which indicate that StAR gene may be involved in the regulation of yak reproduction associated with ovary and corpus luteum function.

The purpose of this study was to find out the molecular mechanism of skeletal muscle energy metabolism and muscle fiber transformation due to Glut4 gene mutation. Glut4^Q177L mutant mice were constructed by CRISPR/Cas9. The animals were divided into 2 groups including 22-week-old healthy wild male mice and Glut4^Q177L mutant male mice, 3 in each group, repeated 3 times. Subsequently, the phenotypic evaluation, glucose tolerance and insulin tolerance tests were performed. The expression of genes related to glucose transporters, lipid metabolism and muscle fiber type in gastrocnemius muscle of mice in the two groups were detected by qPCR; Western blot was applied to detect the content of AMPK and its phosphorylation level in gastrocnemius muscle. The results showed that the weight of subcutaneous fat and epididymal fat in mutant mice was significantly lower than that in the control group (P<0.05), and the area under the glucose tolerance curve of mutant mice significantly increased (P<0.01), indicated the glucose tolerance was impaired. The content of triglyceride in serum of mutant mice significantly decreased(P<0.05). The expression of several glucose transporters such as Glut4, Glut1 and Glut12 in gastrocnemius muscle of mutant mice was significantly higher than that in the control group (P<0.05). The limitation of glucose uptake resulted in a significant increase in the mRNA, protein and phosphorylation modification expression level of AMPK(P<0.05), which was the key gene regulating energy metabolism. At the same time, the expression of CD36 and ATGL, which promote fatty acid uptake and lipolysis, were significantly up-regulated (P<0.05). The expression of slow oxidation fiber type (type I) and fast oxidation fiber type (type IIa) related genes significantly increased(P<0.01), while the expression of fast glycolysis fiber type (type IIb) related gene significantly decreased(P<0.05). The results of this study showed that Glut4^Q177Lmutation reduced glucose uptake in skeletal muscle and fat tissue, resulting in compensating glucose uptake by up-regulating other glucose transporters. Besides, the insufficiency of energy could activate AMPK signaling pathway and secrete myokines to meet energy requirement by facilitating lipolysis. In addition, Glut4 mutation promoted the expression of slow oxidation fiber type related gene, rich in mitochondria, to improve energy efficiency. Glut4^Q177Lmice can not only provide an effective animal model of skeletal muscle insulin resistance, but also provide gene editing reference sites for animal breeding.

This study aimed to investigate the effect and mechanism of deoxynivalenol (DON) on the maturation and development of bovine oocytes in vitro. Bovine oocytes were matured in vitro in the mature solution containing different concentrations of DON (0,50,250,500,1 000 ng·mL^-1), respectively. The expansion degree of cumulus cell and first polar body discharge rate were detected to construct DON toxicity model. Mitochondrial distribution of oocytes, fertile cleavage rate, blastocyst development rate were determined to evaluate the effect of DON on bovine cocytes in vitro maturation and development. And the oxidative stress,where the level of the ROS and GSH and the mRNA expression of CAT、GPx4 were detected to reveal the mechanism of DON action. It was found that the first polar body excretion of the oocytes was reduced by 250 and 500 ng·mL^-1 (P<0.05) and 1 000 ng·mL^-1 of DON(P<0.01).The expansion degree of cumulus cells was significant inhibited by 250 ng·mL^-1 of DON (P<0.05), extremely significant inhibited by 500 and 1 000 ng·mL^-1 of DON (P<0.01). In subsequent experiments, 500 ng·mL^-1 of DON was selected as the toxicity model (DON group) to compare with the group without DON (control group). The results showed that the mitochondrial uniform distribution was significanly different between the control group and DON group (60.2% vs. 40.0%, P<0.05). While fertile cleavage rate ((33.6±3.6)% vs. (67.7±2.6)%, P<0.05) and blastocyst rate ((0.0±0.0)% vs.(18.3±2.2)%, P<0.05) were significantly reduced in DON group compared with the control group. The relative level of ROS in the DON group was higher than that in the control group (1.6 vs.1.0, P<0.05), however, the relative level of GSH in the DON group was lower than that in the control group (0.4 vs.1.0, P<0.05), and the relative mRNA expression level of antioxidant related genes CAT and GPX4 in the DON group were lower than those in the control group (0.3 vs.1.0; 0.6 vs. 1.0, P<0.05). The results indicates that DON inhibits the maturation in vitro and early embryo development of bovine oocyte, and the mechanism is related to DON disturbing the balance of antioxidant system of bovine oocytes.

This study aimed to investigate the location and expression of glutathione peroxidase 6(GPx6) in epididymal cells of Large White boars as well to explore their correlation with reproductive performance of boars. Three female and male Large White pigs at 15 months old were selected, respectively. Testis, epididymis, prostate, urethral bulb gland, seminal vesicle, ovary and fallopian tube were collected for protein extraction. Expression and localization of GPx6 protein in different tissues and cells were detected by Western blot and immunohistochemistry (IHC). Boar fertilization ability was evaluated based on a mathematical mode, according to the standard of breeding parity ≥ 20 births and 3 times of breeding semen from the same boar, 20 Large White boars were selected along with their semen collected. Further, productive performance data of the 1 279 boar-paired sows were collected for evaluating the reproductive performance of those 20 breeding boars including total number born per litter (TNB), number born alive per litter (NBA), farrowing rate (FR) and fecundity. Protein from semen and sperm samples were extracted, BCA and ELISA were carried on to detect GPx6 content in sperm and seminal plasma. SPSS software was used for data statistics, while independent sample t-Test and one-way ANOVA were carried out for significant difference analysis, bivariate Pearson was used for correlation analysis, and P<0.05 indicated significant difference or correlation. The results indicated that GPx6 protein was highly expressed in epididymis, and IHC results showed GPx6 was expressed in apical cells, basal cells, halo cells, principal cells and spermatozoa from epididymis whereas was not expressed in myoid cells. The concentration of GPx6 protein in seminal plasma was as 7 times higher than that in sperm, meanwhile, the concentration of GPx6 protein in semen was negatively correlated with NBA and TNB. This study suggests that GPx6 is expressed in apical cells, basal cells, halo cells, principal cells and spermatozoa of epididymis, and its content in semen affects reproductive performance of boars, which provides a theoretical and experimental foundation for the research of function of GPx6 protein in boar fertility.

The purpose of this study was to isolate coding sequence of PYGO2 gene in pig, obtain its multi-tissue mRNA expression patterns, structural characteristics of protein and localization in cell, and construct the protein-protein interaction network. The coding sequence of PYGO2 was cloned from testis tissue of adult BMI using RT-PCR. The bioinformatics methods was performed to dissect its gene structure and protein functions, compare amino acid homology in mammals, construct phylogenetic tree and protein-protein interaction network. PYGO2 mRNA expression profiles in 15 tissues were detected using qPCR technology. The subcellular location of PYGO2 protein was conducted by constructing the expression vector of pEGFP-C1-PYGO2 and transfecting into ST cell. The results showed that the CDS sequence of PYGO2 was 1 221 bp, encoding 406 amino acids, and located on the chromosome 4 of pig genome. The accession numbers of gene and amino acid in GenBank were KY644518 and AVB77243.1, respectively. The secondary structure of PYGO2 protein contained mainly random coil with hydrophodic N and C terminal. The homology analysis of amino acid sequences implied that the similarities were more than 97% between pig and other mammals, suggesting high conservation of PYGO2 in evolution. The analysis of interaction network of proteins represented that pig PYGO2 had interactions with 9 proteins, and interacted most intensively with BCL9 protein. Further, multi-tissue qPCR results suggested that PYGO2 mRNA were extensively expressed in the 15 detected tissues and with higher expression in gonads. The result of subcellular location in transfected ST cells indicated that PYGO2 protein was predominantly localized in the nucleus. This study obtained the coding sequence of PYGO2 gene, protein structure and location, interaction network of protein, expression characteristics of mRNA in multiple tissues, which will provide a reference for further explanation of molecular mechanisms on pig PYGO2 during spermatogenesis.

The purpose of this study was to detect the expression of PPP1R3C in different tissues of AA broilers and to explore the effects of exogenous insulin and energy restriction on the expression of PPP1R3C in insulin sensitive tissues of chickens. In experiment 1, tissue samples of female broilers at different developmental stages (E14, E19, D7 and D21, n=10) were taken to detect the expression of PPP1R3C in chest muscle by qRT-PCR technique; In experiment 2, the tissue samples of D24 male broilers at different time points (0, 15, 120 and 240 min, n=5) after intraperitoneal injection of insulin or PBS were taken, to detect the expression of PPP1R3C in different tissues of broilers, and to explore the effect of exogenous insulin treatment on the expression of PPP1R3C in insulin sensitive tissues of broilers; In experiment 3, one group of D18 female broilers was fed with conventional diet (n=20) and the other group was fed diet with 30% energy restriction (n=20). After feeding for 48 days, slaughtering samples were taken to explore the effect of 30% energy restriction on the expression of PPP1R3C in broilers; In experiment 4, D7 female broilers were randomly divided into 3 groups:control group, 15% energy restriction group and 15% protein restriction group (n=10). Slaughtering samples were taken from D21 female broilers to explore whether energy restriction was dose-dependent. The results showed that:1) PPP1R3C was highly expressed in chest muscle, followed by heart and leg muscle(P<0.05). 2) The expression of PPP1R3C showed a increasing trend with the growth and development of chicken. 3) Insulin injection significantly down-regulated the expression of PPP1R3C in chest muscle, and the expression of PPP1R3C at 120 min after insulin injection was significantly lower than that at 0 and 15 min(P<0.05); There was no significant change in the expression of PPP1R3C in chest muscle after PBS injection, the expression of PPP1R3C in INS group was significantly lower than that in PBS group at 120 and 240 min after injection(P<0.05). Insulin injection also decreased the expression of PPP1R3C in liver, and the expression of PPP1R3C after insulin treatment for 15 min was significantly lower than at 0 min (P<0.05); The expression of PPP1R3C in liver was in dynamic balance after PBS injection, at 120 min after injection, the expression of PPP1R3C in INS group was significantly lower than that in PBS group(P<0.05). The expression of PPP1R3C in abdominal fat was opposite to that in chest muscle and liver after insulin injection, the expression of PPP1R3C at 15 min after insulin injection was significantly higher than that at 0,120 and 240 min(P<0.05), but there was no significant difference among 0, 120, 240 min; There was no significant change in the expression of PPP1R3C in abdominal fat after PBS injection, the expression of PPP1R3C in INS group was significantly higher than that in PBS group at 15 min after injection (P<0.05). 4) The expression of PPP1R3C in chest muscle and liver was significantly down-regulated by 30% energy restriction (P<0.05). 5) 15% energy restriction and 15% protein restriction did not significantly affect the expression of PPP1R3C in chest muscle. The study results showed that the expression of PPP1R3C was the highest in the chest muscle, and increased with the development of broilers, and the effect of exogenous insulin on the expression of PPP1R3C had obvious tissue specificity. At the same time, the results of energy restriction showed that 30% energy restriction could produce an effect similar to that of exogenous insulin, and the energy restriction had a certain dose dependence, which laid a foundation for further revealing the function of chicken PPP1R3C.

The purpose of this experiment was to study the effect of adding Bacillus subtilis to milk replacer on the growth performance, tissues and organs development, diarrhea rate and fatty acids deposition in muscle in 7-28 days old Hu lambs. Thirty 7-day-old Hu male lambs (twins) with well-developed body conditions were selected and divided into 2 groups randomly according to the principle of homogeneity, 15 lambs in each group and each one as a repeat. Lambs in the two groups were fed milk replacer with a Bacillus subtilis content of 0 and 0.2%, respectively. The test lasted for 21 days. The lambs were weighed before morning feeding at 7, 14, 21 and 28 days of age, and then the average daily gain (ADG) of each growth stage was calculated. The feces conditions were observed during the whole feeding trial, and the lamb diarrhea rate was calculated. At the age of 28 days, 8 lambs in each group were randomly selected for slaughter. After slaughter, the weight of each tissue and organ was weighed, and the relative index was calculated. The longissimus dorsi and biceps brachii of lamb were collected to measure the intramuscular fat content. The results showed that:1) Bacillus subtilis significantly reduced the final weight of 7-14 days old lambs (P<0.05), significantly increased the ADG of 15-21 and 22-28 days old lambs (P<0.05). Bacillus subtilis increased the ADG of 7-28 days old lambs (P=0.100). Bacillus subtilis had no significnat impact on the diarrhea rate of lambs (P>0.05). 2) Bacillus subtilis significantly reduced the pancreas weight of 7-28 days old lambs (P<0.05), and significantly increased the proportion of hooves weight to live weight before slaughter (P<0.05). Bacillus subtilis had no significant effect on other tissues and organs of lambs (P> 0.05). 3) Bacillus subtilis had no significant effect on the skin and wool development of 7-28 days old lambs (P>0.05). 4) Bacillus subtilis significantly reduced the content of unsaturated fatty acid (UFA), monounsaturated fatty acid (MUFA), palmitic acid, stearic acid, eicosanoic acid, palmitoleic acid, oleic acid and MUFA:polyunsaturated fatty acid (PUFA)(P<0.05), and significantly increased saturated fatty acid (SFA):UFA and content of pentadecane acid, myristoleic acid and nervonic acid in longissimus dorsi of lambs (P<0.05). Bacillus subtilis significantly reduced the contents of UFA, SFA, MUFA, palmitic acid, stearic acid, eicosanic acid, palmitoleic acid, oleic acid and MUFA:PUFA(P<0.05), and significantly increased the content of PUFA, n-6PUFA, myristoleic acid, nervonic acid and SFA:UFA, PUFA:SFA in biceps brachii of lambs (P<0.05). Supplementing Bacillus subtilis to milk replacer did not affect the diarrhea rate, organs and skin development of 7-28 days old Hu lambs, however, the ADG and carcass weight of lambs tended to increase. Supplementing Bacillus subtilis significantly reduced the content of UFA, MUFA, and MUFA:PUFA in the longissimus dorsi and the content of UFA, SFA, MUFA, and MUFA:PUFA in the biceps brachii of Hu lambs, while significantly increased the SFA:UFA in the longissimus dorsi and the contents of PUFA, n-6PUFA, and SFA:UFA, PUFA:SFA in the biceps brachii of Hu lambs. The result shows that supplementating Bacillus subtilis can improve the meat quality of Hu lambs by regulating the composition and content of intramuscular fatty acids.

This study aimed to explore the effects of dietary supplementation of synbiotics, as a possible antibiotic substitute, on meat quality, serum biochemical indexes, antioxidant capacity and immune function of Cherry Valley ducks. A total of 540 one-day-old Cherry Valley ducks were randomly assigned to 3 groups with 6 replicates of 30 ducks each. The ducks were fed with basal diet free from antibiotics (control group), basal diets +bacitracin zinc (40 mg·kg^-1, antibiotic group), and basal diet+synbiotic (1 000 mg·kg^-1, synbiotic group). The experimental period lasted for 42 days, which consisted of starter period (1-14 d) and grower period (15-42 d). At day 14 and 42 of the experiment, one male duck whose weight was close to the average body weight from each replicate was randomly selected, weighed and slaughtered. Then blood, muscle, immune organs and intestinal mucosa samples were collected for the determination of serum biochemical indexes, muscle quality, immune organs indexes, antioxidant indexes, and the expression of intestinal immune-related genes. The results showed that:1) Dietary supplementation of synbiotics or antibiotics significantly reduced the cooking loss of breast and thigh muscles (P<0.05) and the brightness value of thigh muscle (P<0.05), and significantly increased the redness value of thigh muscle at 24 h after slaughter (P<0.05). 2) Compared with control group, except for the significant increase of spleen index at 42 d in antibiotic group (P<0.05), dietary supplementation of synbiotic or antibiotic had no significant effect on the serum biochemical indexes and immune organ indexes of Cherry Valley ducks (P>0.05). 3) In synbiotic group, glutathione peroxidase (GSH-Px) activity in the serum at 14 d was higher than that in control and antibiotic groups (P<0.05), the activity of superoxide dismutase (SOD) in jejunal mucosa at 42 d was higher and malonaldehyde contents in jejunal mucosa at 14 d was lower than those in the control group (P<0.05). Compared with control group, dietary supplementation of synbiotic or antibiotic significantly increased jejunal mucosal GSH-Px activity at 42 d (P<0.05), then ileal mucosal GSH-Px activity at 14 d in antibiotic group was higher than that in control and synbiotic groups (P<0.05). 4) The mRNA expression of Toll-like receptor 3 (TLR3) in jejunum mucosa in synbiotic group at 14 d was higher than that in the control group (P<0.05), but no significant difference compared with antibiotic group (P>0.05); the mRNA expressions of retinoic-acid-inducible gene I (RIG-1) in the ileal mucosa at 14 and 42 d in synbiotic group were significantly higher than that in control and antibiotic groups (P<0.05); Compared with control group, dietary supplementation of synbiotic or antibiotic significantly upregulated mRNA expression of TLR3 and TLR7 in the ileal mucosa at 14 d (P<0.05). Based on the above results, the synbiotic, as a substitute for antibiotics, could improve the meat quality, promote the antioxidant capacity, enhance the expression of immune-related genes in the intestinal mucosa and improve the immunomodulation of Cherry Valley ducks.

This study investigated the effects of different dietary protein sources and nisin on rumen fermentation and rumen microbiota in fattening Hu sheep. Thirty-two male Hu lambs ((23±2) kg initial BW) were assigned to 4 dietary treatments in a randomized block design with a 2×2 factorial arrangement. Two blocks were designed according to body weight with 16 lambs each. Two protein sources (soybean meal (SBM) and dried distillers grains with solubles (DDGS)), and two levels of nisin (0 and 30.5 mg·kg^-1 DM) were used to formulate 4 isonitrogenous and isoenergetic diets. The feeding trial was conducted for 10 weeks, with the first 1 week for adaptation followed by 9 weeks of dietary treatment. At the end of the experimental period, 6 lambs (3 lambs per block) were randomly selected from each group, and slaughtered for rumen contents collection. Metagenomic DNA of rumen content was extracted, and rumen microbiota were analyzed by Illumina MiSeq sequencing and quantitative PCR. No interaction (P>0.05) of protein×nisin was found on all measured indicators (rumen fermentation characteristics, ruminal microbial populations, rumen bacterial diversity and relative abundance, etc.) except for the relative abundance of Ruminococcaceae NK4A214 group and unclassified Bacteroidetes. Nisin supplementation had no impact on all measured indicators (P>0.05). Lambs receiving DDGS had lower concentrations of ruminal acetate, ammonia and branched-chain VFA (BCVFA) compared with lambs fed SBM (P<0.05). The DDGS-fed lambs had a smaller (P<0.05) population of protozoa and C. aminophilum than those fed SBM, but the population of total bacteria, fungi, and methanogens were similar (P ≥ 0.053). For alpha diversity, ACE and Chao1 index were higher (P<0.05) in the DDGS-fed lambs than in those fed SBM. At phylum level, the dominant bacteria in different diet treatment groups were Bacteroidetes and Firmicutes. At genus level, the dominant bacteria in each treatment group were Prevotella 1, Christensenellaceae R-7 group and Ruminococcaceae NK4A214 group. None of the relative abundance of bacteria at phylum level was affected (P ≥ 0.14) by protein sources. Compared with those fed SBM, the relative abundance of Pseudobutyrivibrio and Roseburia were higher (P<0.05), while the relative abundance of Butyrivibrio 2 and Ruminococcaceae UCG-005 were lower (P<0.05) in DDGS-fed lambs. Replacing SBM in an isonitrogenous lambs diet with DDGS changed the rumen fermentation characteristics and the microbial community structure, and the reduction of the population of protozoa and C. aminophilum may be the main reason for the reduction of rumen ammonia concentration. Nisin supplementation at 30.5 mg·kg^-1 DM had no effects on rumen fermentation and rumen microbiota in fattening lambs.

The experiment was designed to investigate the effects of LED lights on the fiber quality and skin follicle development of Su line Angora rabbits. A total of 50 three-month-old Su line Angora rabbits with body weight of (2.245±0.296) kg were randomly assigned to 5 different groups, 5 replicates in each group and 2 rabbits in each replicate. Treatment groups were exposed to red, green and blue LED lights with the same intensities (50 lx) and 16 h light (L):8 h dark (D) photoperiod regimes. Black group was exposed in dark environment. Control group was exposed to natural light. The trial lasted for 73 days. At the end of the trial, wool samples were taken to determine the quality of fiber, blood samples were collected to determine hormonal indicators, and skin tissue was taken to observe hair follicle development. Results showed that:1) All treatments had no significant effect on final weight, average daily gain (ADG) and feed intake (P>0.05), but red group improved the wool yield, which was higher than control, green and black groups (P=0.050). 2) The shoulder fiber length of red group was significantly improved, and was 35.36% longer than control and green groups (P<0.05). Ratio of coarse fiber in red group was significantly reduced (P<0.05), and was lower than that in green group. Diameter of coarse fiber in control group was significantly smaller than green and black groups (P<0.05). Diameter of fine fiber in red group was the finest, and there was no significant difference among groups (P>0.05). Moisture content had no significant difference among groups (P>0.05). 3) Compared with control group, red group could significantly increase the concentration of serum melatonin (MT) and triiodothyronine (T3) (P<0.05), and black group significantly decreased the concentration of prolactin (PRL) (P<0.05). 4) The tissue sections showed that red group had the largest number of hair follicle groups (16.5), and each group was composed of many secondary hair follicles and very few primary hair follicles, and equally distributed. The structure of hair follicles in control, blue and black groups were at normal level. Green group had the lowest number of hair follicles groups (10.0) and the distribution was uneven. The results indicated that LED red light can promote the secretion of MT, increase the number of hair follicle groups and secondary hair follicles in the skin tissue of Su line Angora rabbits, so as to improve the quality of fibers.

DNA damage response (SOS response) refers to an important protective mechanism for bacteria to cope with genomic DNA damage. The RecA protein plays a key regulatory role in the induction of SOS responses in many bacteria, and its homologous proteins are widely present in various organisms. The purpose of this study was to explore whether RecA protein regulates the SOS response of Riemerella anatipestifer. We constructed the recA deletion mutant and complemented strain. The growth abilities of the parental strain, deletion mutant and complemented strain, the transcriptional levels of recA gene and SOS response of the above strains with ultraviolet treatment were detected. The results showed that the recA deletion mutant ΔrecA and complemented strain cΔrecA were successfully constructed. Inactivation of recA gene had no significant effect on the growth rate of RA-GD strain. Under ultraviolet radiation irradiation, the transcription level of recA gene of parental strain increased significantly. Compared with the parent strain and the complemented strain, the survival ability and the genomic integrity of the deletion strain reduced significantly. This study confirmed for the first time that the RecA protein is involved in the SOS response of Riemerella anatipestifer.

This study aimed to investigate the antimicrobial resistance phenotype, genotype, and molecular characteristics of Staphylococcus pseudintermedius isolated from clinical samples in dogs. From November 2017 to April 2019, 601 samples were collected from the Veterinary Teaching Hospital of China Agricultural University (VTH-CAU) and third-party testing organizations, and identified by PCR amplification of 16S rDNA gene sequencing. Antimicrobial susceptibilities of S. pseudintermedius strains were determined by agar microdilution method according to the CLSI recommendations. All strains were subjected to whole genome sequencing (WGS). Then resistant genes, multilocus sequence typing (MLST), SCCmec types were deduced from WGS data. A total of 75 (12.5%) S. pseudintermedius were isolated from all clinical samples, including 42 (56%) methicillin-resistant S. pseudintermedius (MRSP) and 33 (44%) methicillin-susceptible S. pseudintermedius (MSSP). All of S. pseudintermedius were highly resistant to penicillin, azithromycin, clindamycin, doxycycline, enrofloxacin, ciprofloxacin, chloramphenicol and oxacillin; and were sensitive to linezolid, vancomycin, amikacin and rifampicin. Multi-drug-resistant (MDR) rate of 75 S. pseudintermedius were 90.7% (n=68/75), while all of MRSP isolates (100%, n=42/42) were MDR. Nineteen antimicrobial resistanct genes were detected by WGS. The detection rate of blaZ and aac(6')-aph(2″) were the highest, both were 92% (69/75). A total of 70 sequence types (STs) were detected, and 54 were novel. There were no dominant STs in this study. Among 42 MRSP isolates, 23 (54.7%) belong to staphylococcal cassette chromosome mec (SCCmec) V. This study showed that MDR of MRSP and MSSP were both high, which presents very important issue that MDR-MSSP cannot be ignored; and high genetic diversity among S. pseudintermedius exhibited in China.

The purpose of this study was to identify the pathogenic bacteria that killed the forest musk deer in a forest musk deer farm in Tianshui, Gansu Province, and to analyze its pathogenicity, drug resistance and the whole genome sequence. The bacterial strains were isolated and purified from the lungs of dead forest musk deer. Then the isolate was identified through biochemical test and 16S rRNA gene sequence analysis. Subsequently, the pathogenicity and drug sensitivity of the isolate were analyzed. And based on the whole genome sequence, the whole genome sequence of the isolate was assembled and annotated. In addition, the phylogenetic analysis of the virulence genes toxA and exoT was completed. The results showed that a strain of Pseudomonas aeruginosa was isolated from the lung of the dead forest musk deer and named TS2019. The LD₅₀ of TS2019 in mice was 2.82×10⁷ CFU·mL^-1. The results of drug sensitivity test demonstrated that TS2019 had multiple drug resistance, but it was sensitive to ciprofloxacin, lomefloxacin, etc. The results of genome sequencing showed that the genome size of TS2019 was 6 308 327 bp, including 5 929 genes, of which 1 035 genes were involved in metabolic pathways. There were 875 genes encoding virulence factors which included adhesion proteins, regulatory factors, toxic proteins, etc. There are 5 288 genes related to antibiotic resistance such as tetracycline and aminoglycoside in the genome. The results of the phylogenetic analysis showed that virulent genes toxA and exoT of TS2019 shared over 99% homology with corresponding genes of many P. aeruginosa strains in GenBank. And the phylogenetic analysis of the eoxT gene showed the genetic relationship between TS2019 and P33 strain isolated from human in Hangzhou, was the closest, but it was an independent branch. In this study, a strain of P. aeruginosa was isolated and identified from the lungs of the dead forest musk deer, and the strong pathogenicity and multi-drug resistance of the isolate had been confirmed. The virulence genes toxA and exoT had high homology with the corresponding gene sequences of P. aeruginosa in GenBank. The results provided the theoretical support for the prevention and treatment of P. aeruginosa infection-related diseases of forest musk deer, and also laid a foundation for further study on the pathogenic mechanism and drug resistance mechanism of P. aeruginosa.

Mannheimia haemolytica and Pasteurella multocida capsular serotype A both are Gram-negative, bipolarity staining cocobacilli, the main bacterial pathogens that lead to the bovine respiratory disease, resulting in significant economic losses to the cattle industry every year. At present, the lack of vaccines is still the key points of non-effective control to both pathogens. Here, bovine M. haemolytica (Mh) strain Mh422 and bovine P. multocida capsular serotype A (Pm) strain PmCQ2 isolated from calves were used as strains for inactivated bacterins. Overnight culture of Mh422 or PmCQ2 was seeded in Martin broth medium, and incubated at 37℃ for 12 h with shaking at 220 r·min^-1, the bacterial cells were collected and inactivated with 0.4% formalin, the monovalent inactivated bacterins with two concentration of Mh and Pm were prepared by the routine method, and Mh-Pm combined inactivated vaccines were made by using the mixture of Mh and Pm monovalent inactivated bacterin with a ratio of 1:1, 2:1 and 3:1. The mice were inoculated subcutaneously with monovalent and combined vaccines at a dose of 0.2 mL, respectively, the control group mice were inoculated with PBS emulsifier, and the mice had no adverse reactions after immunization with all inactivated vaccines. Booster immunizations were conducted with a half dose of the primary immunization on the 7th and 17th day, blood was sampled via tail vein on the 7th day and every 5 days thereafter and serum antibody titers were detected by ELISA, the specific antibodies were generated to high levels at the 10th day after the first booster and continue increase to the peak at the 15th day after the second booster and maintained 25 d then decreased slowly. Mice were challenged intraperitoneally with Mh422 and PmCQ2 on the 20th day after the third immunization, the results showed that the immune protective rates of Pm monovalent and combined inactivated vaccines against PmCQ2 strain were all 100%, but the immune protection rates of Mh monovalent inactivated vaccines against Mh422 were 0%, there were no cross-immune protections between Mh and Pm. Interesting here, the immune protection rates of Mh-Pm combined inactivated vaccines against Mh422 strain were up to 53%-71%. The results indicate that there is no mutual inhibition between Mh and Pm in its special antibody production inducing and PmCQ2 can promote the immune protection of Mh inactivated vaccines against Mh422. This study provides a theoretical basis for the further research on the combined vaccine of bovine M. haemolytica and bovine P. multocida.

Porcine epidemic diarrhea (PED) is a highly contagious disease, which mainly harms piglets less than 1 week of age, and the infection mortality rate of piglets is up to 100%, and it is a major disease that harms the world's pig industry. We aimed to prepare a specific nanobody against porcine epidemic diarrhea virus (PEDV) S protein and to identify its binding activity. The prokaryotic expression and purification of PEDV S1 protein were performed, and the purified recombinant PEDV S1 protein was used to immunize Bactrian camel. The peripheral blood lymphocytes were isolated, the lymphocyte RNA was extracted, and the cDNA was obtained by reverse transcription. The VHH fragment was amplified by nested PCR, then was constructed into pCANTAB-5E vector and transformed into TG1 competent cells, the VHH phage antibody display library was obtained. The constructed phage antibody display library was rescued and enriched for three rounds. Phage display technology was used to screen the PEDV S protein nanobodies from the library. The specificity and binding force of the selected specific nanobodies were verified by ELISA. The binding activity of the nanobody to PEDV was verified by Western blot and indirect immunofluorescence. Results were as follows:PEDV S1 protein was successfully expressed and purified and the titer of specific antibodies in the serum of Bactrian camels reached 1:256 000 after four immunizations of the PEDV S1 protein. The capacity of the library was 2.1×10⁷, and the positive rate was 85%. After three rounds of screening and enrichment of the display library, six nanobodies with different amino acid sequences were screened out. ELISA results showed that all of them have good binding ability and specificity for PEDV S1 recombinant protein. Subsequently, it was verified that Nb3 can bind to PEDV virus, indicating that it has good activity. The specific nanobodies against PEDV S1 protein were successfully screened. The screened nanobodies are expected to be used for the diagnosis and treatment of PED, and provide antibody materials for the study of the pathogenic mechanism of PEDV.

The present study aimed to investigate the prevalence and genetic evolution of hepatitis E virus (HEV) in Tibetan pigs in Sichuan. Three hundred and thirty-two Tibetan pig fecal samples collected from 22 Tibetan pig farms in Ganzi Tibetan Autonomous Prefecture and Aba Tibetan Autonomous Prefecture of Sichuan Province from 2018 to 2020 were tested for HEV by RT-PCR, and the positive samples were genotyped. The results of RT-PCR showed that the positive rate of HEV nucleic acid was 20.48% (68/332, 95% CI=16.3%-25.2%), the positive rate of HEV pig farms was 77.27% (17/22, 95% CI=54.6%-92.2%), the positive rate of healthy samples was 2.86% (3/105, 95% CI=0.6%-8.1%), and the positive rate of diarrhea samples was 28.63% (65/227, 95% CI=22.8%-35.0%) in 22 large-scale Tibetan pig farms. Phylogenetic analysis showed that all positive strains were G4 type. In order to further study the evolution process of epidemic strains in this area, Bayesian evolutionary analysis software was used to estimate the divergence time, and the results showed that the divergence time of epidemic strains in Tibetan pigs was as early as 1999 and as late as 2016. The complete genome sequences were obtained from one positive sample each year, and the nucleic acid sequence identities were 89.5%-93.1%. Recombination was found in SWU/301/2019 by analysis of three genome-wide recombinations, and the SWU/301/2019 recombination region was located at 3 746-4 655 bp of ORF1. This study is the first to investigate HEV in Tibetan pigs in Sichuan. The results show that there is a certain degree of HEV infection in Tibetan pigs in Sichuan, which provides a reference for the prevention and control of HEV infection in Tibetan pigs in Sichuan and for the in-depth study of genetic variation and biological characteristics of HEV in Tibetan pigs in Sichuan.

In this study, we constructed a mouse melanoma cell line B16F10 with stable interference targeting Beclin-1 gene by RNA interference, and to explore autophagy and cell viability, which is the foundation for analysis of the relationship between Beclin-1 gene, autophagy, and tumor. Firstly, we designed the shRNA of mouse Beclin-l and constructed interference vectors. Then we transfected the lentiviral vector into 293T cells to obtain lentiviral particles, and B16F10 cells were infected with lentivirus packaging. To obtain the monoclonal cell line, the transfected cells were selected with the methods of pressurized screening and limited dilution. And then the monoclonal cells were cultured in fed-batch mode for quality evaluation. The interference effect of Beclin-l in the stable cell line was detected by RT-PCR and immunofluorescence technique, the expression of autophagy protein LC3 and the formation of autophagosomes were analyzed by Western blot and transmission electron microscopy, and cell viability were determined by CCK-8 assay. The results showed that the lentiviral vector targeting Beclin-l was successfully constructed, and the titer of lentivirus purified by packaging was 1×10⁸TU·mL^-1. Beclin-1 mRNA and protein were inhibited in the stable cell line, and the interference efficiency was around 75% (P<0.01). The results demonstrated that intervention of Beclin-1 expression could inhibit the expression of LC3-Ⅱ protein and the number of autophagosomes, and reduce the viability of B16F10 cells. These data indicated that the silence of Beclin-1 gene could effectively reduce the autophagy intensity and promote cell death in B16F10 cells, which lays the foundation for exploring the function of Beclin-1 gene and the role of autophagy in anti-tumor.

To investigate the effect of fatty acid oxidation (FAO) on autophagy and the expression of pro-inflammatory cytokines in BCG-infected RAW264.7cells. The accumulation of lipid droplets and the content of fatty acids inside RAW264.7 cells after BCG infection were detected by BODIPY staining and free fatty acid quantitative kit. The expression of carnitine palmityl transferase 1A (CPT-1A) in BCG-infected cells was detected by Western blot. After pretreatment with Etomoxir (100 μmol·L^-1) for 2 h, BCG was infected with RAW264.7 cells for 6 h, intracellular survival BCG was assessed by CFU assay, and the expression of Beclin1, LC3-II and lysosomal protein (RAB7) were detected by Western blot. The aggregation of autophagosomes and autophagy flux were detected by immunofluorescence and mRFP-GFP-LC3 adenovirus. Pro-inflammatory cytokines IL-1β, IL-6 and TNF-α mRNA and their concentration in cells culture supernatant were detected by fluorescence quantitative PCR and ELISA, respectively. The results showed that BCG infection promoted the accumulation of lipid droplets and the expression of CPT-1A in RAW264.7 cells, while free fatty acid content decreased. Etomoxir treatment inhibited intracellular BCG survival and elevated the expressions of Beclin1, LC3-II and RAB7. Besides, a large number of autophagosomes were aggregated and autophagy flux was enhanced, however, the mRNA expressions and secretion of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were all inhibited. It is suggested that FAO inhibition promotes RAW264.7 cells autophagy and inhibits the inflammatory response induced by BCG infection.

Field strains of foot-and-mouth disease virus (FMDV) utilize integrin heterodimers αvβ1, αvβ3, αvβ6 and αvβ8 as receptors to gain entry to cells. Using novel real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assays, levels of mRNA of the integrin subunits αv, β3, β6 and β8 were quantified in tissue samples taken from ovine foetuses at 45, 75 and 110 days of gestation, neonatal lambs and adult ewes. The results showed that in the coronary band that the level of β6 mRNA of adult ewes and neonatal lambs was lower than that of foetuses at 75 and 110 days of gestation; In the heart, the level of β6 mRNA of adult ewes, neonatal lambs and foetuses at 110 days of gestation was higher than that of foetuses at 45 and 75 days of gestation; In the muscle, the level of β6 and β8 mRNA of foetuses and neonatal lambs was higher than that of foetuses at 45 and 75 days of gestation. In the tongue epithelium, the level of β3 mRNA in adult ewes was lower than that in other stages. In the soft palate and tonsil, there was little variation in the level of integrin mRNA between stages. In this study, the quantitative changes in integrin subunit mRNA distribution in sheep across different developmental stages have been assessed for the first time, which would provide a useful insight into the role of integrins in the pathogenesis of FMD in vivo.

The purpose of this study was to investigate the distribution of vessels and nerves in different parts of yaks skin, to detect the location relative expression of HIF-1α in different parts of yaks skin, and to explore the adaptation mechanism of yaks skin to the plateau hypoxia environment. The vessels and nerves in the skin of adult yaks were observed and analyzed by HE, Masson's staining and Verhoeff VG staining. The expression and distribution of HIF-1α mRNA and protein in yaks skin were studied by immunohistochemistry, real-time quantitative PCR and Western blot. The results showed that the density of vessels and nerves was the highest in the neck, followed by the forearm and crus, and the lowest in the metatarsus, there were significant differences among the parts (P<0.05). The number of vessels and nerves from the neck to the metatarsal showed a decreasing trend, with a significant difference between different sites (P<0.05). HIF-1α was mainly expressed in the epidermis, the epithelial root sheath of hair follicles, sebaceous glands, sweat glands, vessels and nerves; Strong positive expression was found in the neck, forearm and crus, and positive expression in the metatarsus (P<0.05). The relative expression level of HIF-1α mRNA in the metatarsus was significantly lower than that in the other three sites (P<0.05), but there was no significant difference in the other three sites (P>0.05). The relative expression of HIF-1α protein was the highest in the neck and the lowest in the metatarsus. The difference was significant (P<0.05). The results showed that the morphology and structure of different vessels and nerves in the skin of adult yaks were similar, and the density of vessels and nerves varied significantly from neck to forelimb to hind limb. The differential expression of HIF-1α further indicates that the skin plays a role in the adaptation of yaks to hypoxia.

This study aimed to investigate the protective effects of camel whey protein (CWP) on liver injury, oxidative stress, and liver function of rats under heat-stressed (HS). Thirty six 6-week-old SD rats were selected and randomly divided into 6 groups after 2 weeks of adaptive feeding:the control group fed a basal diet, the CWP control group supplemented with 400 mg·kg^-1of CWP, the HS group received 2 h HS treatment per day for 8 d in addition to the basal diet, and the CWP intervention group received 100, 200, and 400 mg·kg^-1of CWP before each HS treatment. Liver histological changes were observed by HE staining, and liver function biomarkers, oxidative stress markers, and antioxidant enzyme activities were detected. The results showed as follows:CWP intervention reduced HS serum aspartate transaminase (AST) and alanine transaminase (ALT) activities, and 400 mg·kg^-1CWP had the best effect (P<0.01). And 400 mg·kg^-1CWP effectively reduced HS-induced histopathological changes in the rat liver. CWP suppressed hepatic reactive oxygen species (ROS) and malondialdehyde (MDA) levels, and enhanced superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities as well as glutathione (GSH) levels, with 400 mg·kg^-1CWP having the best effect (P<0.01). These results suggested that CWP intervention could alleviate HS-induced liver injury in rats by suppressing hepatic oxidative stress and enhancing antioxidant system defenses in a dose-dependent manner.

The subtypes, antimicrobial resistance, virulence genes of enterococci isolated from poultry farms in Guangdong province were investigated and analyzed, aimed to provide theoretical basis for the control of resistance spread of animal origin enterococci and public health. A total of 493 intestinal samples were collected from 4 poultry farms in Guangdong province in 2018 for isolation and identification of E. faecalis and E. faecium. All the isolates were characterized by antimicrobial susceptibility using the agar dilution method, detection of antimicrobial resistance genes and virulence genes by PCR. Results were as follows:1) The results showed that a total of 125 isolates were obtained, including 84 E. faecalis (66 from chicken and 18 from duck) and 41 E. faecium from chicken intestinal samples. 2) The strains were almost all resistant to tetracycline, doxycycline, erythromycin. The antimicrobial resistance rates of florfenicol and chloramphenicol were as high as 89.60% and 74.40%, respectively. In general, the antimicrobial resistance rate of E. faecium was higher than that of E. faecalis, and the resistance rate for ciprofloxacin and linezolid in E. faecalis was higher than that in E. faecium. The resistance rate to linezolid was significantly higher in E. faecalis from duck (94%) than that from chicken (39.4%). However, all E. faecium were susceptible to linezolid. One E. faecalis strain from the chicken sample was resistant to vancomycin. 3) The detection rate for resistant genes in E. faecium was higher than that in E. faecalis, and the detection rate in duck isolates was higher than that in chicken isolates. Genes tetL, fexA and ermB were the most popular, with detection rates above 90%, followed by optrA (73.60%), and poxtA and fexB, being less than 20%. The cfr gene was detected in 3 E. faecalis from duck. 4) Among virulence genes tested, efaA was the most prevalent, with a detection rate of 63.04% (58/92), followed by gelE (54.35%, 50/92), ace (47.83%, 44/92) and asal (44.57%, 41/92). The strains resistant to CIP and HLAR and those harboring cfr mostly carried the virulence genes aggA, asal, gelE or ace. Enterococci from poultry farms presented serious antimicrobial resistance, and particularly strains from ducks demonstrated a high resistance rate to Linezolid. Antimicrobial-resistant genes and virulence genes are prevalent and diverse. Genes conferring resistance antimicrobials relevant to human medicine have also been detected. Therefore, it is necessary to strengthen the monitoring of enterococci resistance in poultry farms.

This study aimed to investigate the effect of Bupleurum polysaccharide on lead-induced liver and kidney damage in mice. One hundred and fifty SPF male healthy Kunming mice were selected for the experiment. After two weeks of adaptive feeding, they were randomly divided into 5 groups, namely the control group, the lead treatment group, the lead treatment + Bupleurum polysaccharide low, medium and high dose groups (100, 200 and 400 mg·kg^-1). Establishment of the poisoning model:the mice drink lead water (0.5% lead acetate) every day for 4 consecutive weeks. After the modeling was completed, the test group was given Bupleurum polysaccharide once daily for 2 weeks. The lead content and body mass in the blood and tissues of mice were measured, and the antioxidant enzyme activity, Lipid peroxidation level and inflammatory factors were detected and analyzed, and the relative expression of oxidative damage and inflammatory response related factors mRNA was analyzed from the molecular level. The results showed that compared with the lead-treated group, Bupleurum polysaccharides can inhibit the decreasing body weight and the increase in the proportion of liver and kidney in lead-poisoned mice. The addition of Bupleurum polysaccharides reduced the lead concentration in the blood and tissues of mice, but the effect was no significant (P>0.05); compared with the lead-treated group, Bupleurum polysaccharide can significantly increase the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and peroxidase (CAT) activity in the liver and kidney tissues of lead-exposed mice (P<0.05), and reduce malondialdehyde (MDA) contents; Bupleurum polysaccharides can significantly reduce the lead-induced increase in alanine transferase (ALT) and aspartate transferase (AST) activities in the serum and liver tissues of mice, and the mice serum urea nitrogen (BUN) and creatinine (Scr) level decreased, and the tumor necrosis factor (TNF-α), interleukin-6 (IL-6) and myeloperoxidase (MPO) activities in liver and kidney tissues of mice significantly decreased (P<0.05); Bupleurum polysaccharide can significantly increase the expression of Nrf2 signaling pathway, increase the mRNA levels of HO-1, Cu/Zn-SOD, Mn-SOD, CAT, and reduce the mRNA level of Keap1. In addition, Bupleurum polysaccharide can significantly reduce the increase of mRNA levels of inflammation factors (NF-κB, IL-1β and TNF-α) in lead-induced mice liver and kidney (P<0.05). The results showed that low-dose, middle-dose and high-dose of Bupleurum polysaccharides can alleviate lead-induced lipid peroxidation and inflammation in mice, and have protective effects on liver and kidney damage in mice. Among them, the most significant effect of Bupleurum polysaccharides high-dose group on liver and kidney tissue damage in mice.

This study aimed to explore the effects of bandaging or not after surgical castration on wound healing, the animal behavior, production performance and blood index of male piglets. Two hundred and twenty-four Duchang male piglets with good health and similar weight were randomly divided into 3 groups, sham operation (group A), wound bandage (group B) and no bandage (Group C) groups were set up. The male piglets were castrated without anesthesia at the age of 5 days and then the related indexes were detected until the age of 21 days. Wound healing, animal behavioral performance, mortality, production performance, serum cortisol (COR) and immunity index were evaluated after the ending of castration and bandaging on male piglets. The results showed that the scores of wound healing degree in the male piglets of group C were significantly higher than those in group B (P<0.05); the behaviors of standing, playing and exploring were significantly reduced (P<0.01) and the behaviors of being alone, screaming, hugging, abnormal urination, unstable standing and fear of man were extremely significantly increased (P<0.01) after surgical castration without bandaging. Wound bandage had obvious effects on the behavior of playing and fear of man; There was no significantly difference between group B and C in the weaning weight and average daily gain (ADG) during the entire test period (P>0.05). Although the mortality caused by surgical castration were increased, the mortality rate of (1.35%) group B was significantly lower than group C (6.41%) within 5 days after surgical castration; The concentration of COR in both group B and C were significantly higher than that of the group A (P<0.01) while the secretion of immunoglobulin A (IgA) and immunoglobulin G (IgG) in serum were significantly lower than group A (P<0.01) within 3 days after surgical castration; However, by the fifth day, the concentration of COR in group B was significantly lower than group C (P<0.05) and the secretion of IgA and IgG in group B were significantly higher than group C (P<0.05) and there was no significantly difference between pre-and post-operation in secretion of interleukin-12 (IL-12) and interferon-γ (IFN-γ) (P>0.05). The above results indicate that the intense pain stress could be caused by surgical castration in male piglets, the post-operative bandaging can significantly reduce the wound redness, swelling, bleeding and the mortality by infection, accelerate wound healing, help ease the pain, promote the recovery of blood indexes, so as to protect the welfare level of male piglets.

In order to explore the clinical application effect of canine parvovirus (CPV) specific immunoglobulin in the treatment of CPV disease, we collected the case records of CPV infected dogs received and treated in Animal Hospital of China Agricultural University from January 2016 to November 2019, and screened out the dogs with complete medical records and were treated with CPV monoclonal antibody or CPV specific immunoglobulin. These dogs were tracked return visit. We analyzed the total cure rate, the cure rate of each initial antibody levels and each month ages and the recovery course of those cases. The results showed that there was no significant difference between CPV specific immunoglobulin and CPV monoclonal antibody in the total cure rate and the cure rate of consistent initial antibody levels and consistent month ages (P>0.05). However, the recovery course of dogs treated with specific immunoglobulin was significantly lower than those treated with monoclonal antibody (P=0.02<0.05). The good clinical application effect of canine parvovirus specific immunoglobulin provides a new choice of drugs treating CPV disease.