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861.
QIN Ke HUANG Xiang ZENG Jian-hua WANG Chen SUN Guan-jie SONG De-qing CHEN Yao-sheng LIU Xiao-hong HE Zu-yong 《中国畜牧兽医》2017,44(3):773-781
In order to assess the purity of Luchuan pig populations, four South Chinese local pig breeds including Putian Black pig, Yuedong Black pig, Dahuabai pig, Bama miniature pig and three foreign pig breeds including Duroc pig, Yorkshire pig and Landrace pig were studied as controls by sequencing of PCR products, MC1R and KIT genotypes in 56 Luchuan pigs were analyzed in this study. Sequencing results indicated that a splicing mutation (G>A) was presented in the first base in intron 17 of KIT gene in both Yorkshire pig and Landrace pig, in contrast, the wildtype GG of KIT gene was presented in Luchuan pig, four south Chinese local pig breeds and Duroc pig.Compared with Hainan wild boar, South Chinese local pig breeds had two missense mutations 95Val > Met and 102Leu > Pro in the coding region of MC1R gene;Compared with Yorkshire pig, Landrace pig and Duroc pig, South Chinese local pig breeds had 5 to 6 SNPs in MC1R gene 5'UTR, and in addtion, an A base deletion in MC1R gene 3'UTR. Furthermore, we found one litter of Luchuan pig with abnormal coat color.The results showed that the presentation of two distinct MC1R genotypes ED1 and Ep in both litters and the sow,but only ED1 in the boar. Considering Ep was derived from Pietrain pig, we preliminarily considered that the genome of the sow might be infiltrated with foreign pig breeds. In summary, we detected the genotypes of the coat color genes KIT and MC1R in eight pig breeds, confirmed the molecular differences of coat color between Chinese local pig breeds and foreign pig breeds, which could be useful for the further investigation of the molecular mechanism of pig coat color. 相似文献
862.
MUC4 and MUC13 genes as important candidate genes for enterotoxigenic Escherichia coil (ETEC) F4 resistance,may play an important role in the process of against ETEC F18 infection in weaned piglets. In this study,ETEC F18-resistant and -sensitive weaned Meishan piglets were used,and the expression levels of MUC4 and MUC13 genes in 11 tissues (heart,liver,spleen,lung,kidney,stomach,muscle,thymus,lymph nodes,duodenum and jejunum) were determined by quantitative Real-time PCR. The results showed that MUC4 and MUC13 genes were broadly expressed with different expression levels in all the 11 tissues. In the thymus and lymph tissues,the expression of MUC4 gene in resistant piglets was significantly higher than that in sensitive piglets (P<0.05);In the lung tissue,theMUC13 gene expression level in resistant individuals was significantly higher than that in sensitive individuals (P<0.05),and in the intestinal tissues of duodenum and jejunum, the expression level of MUC13 gene was relatively higher in resistant individuals. Thus we speculated that the high expression of MUC4 gene in immune tissues and MUC13 gene in intestinal tissues might improve the immune ability of piglets,protect and lubricate the intestinal tract, and resist ETEC F18 infection. 相似文献
863.
GUAN Zhi-hui CHEN Bao-jian PAN Tian-biao QIN Zhao-xian LIU Jia-qi MA Qing-yan NONG Su-qun XIE Bing-kun 《中国畜牧兽医》2017,44(3):628-634
The objective of this study was to clone the acyl-coenzyme A oxidase 1 (ACOX1) gene of Luchuan pig and analyze its genetic structure with bioinformatics. A pair of special primer was designed according to predicted sequence of pig ACOX1 gene in GenBank. The ACOX1 gene was amplified by RT-PCR, the physicochemical property and secondary structure of ACOX1 gene were systemically analyzed by bioinformatics techniques. The results showed that ACOX1 gene fragment included an 1 986 bp whole length CDS (coding 661 bp amino acids). The sequence multi-aligned results showed that Luchuan pig shared 99.5%, 85.5%,87.1%,66.3%,75.6%,84.0%,82.3%,81.1% and 69.1% of similar nucleotide sequence with that of pig,human, zebrafish, chicken, rhesus monkeys, mice, rat and frog, respectively. The prediction of ACOX1 secondary structure showed that Luchuan pig ACOX1 had no signal peptide and transmembrane structure. This study suggested that the whole CDS sequence of ACOX1 gene was successfully cloned in Luchuan pig, and the cloning and analysis of ACOX1 gene provided an important foundation for further studying on the fatty deposition and lipornetabolism of ACOX1 gene in Luchuan pig. 相似文献
864.
溶菌酶是昆虫体液免疫的重要抗菌蛋白质,在昆虫抵御外源物质入侵过程中发挥重要作用。以柞蚕蛹为材料,采用大肠杆菌(Escherichia coli)、蛹虫草菌(Cordyceps militaris)、柞蚕微孢子虫(Nosema pernyi)及无菌水为诱导源,测定不同外源物质诱导柞蚕蛹血淋巴对溶壁微球菌(Micrococcus lysodeikticus)的抑制活性,并根据柞蚕溶菌酶基因(GenBank登录号:DQ353869)设计引物,利用荧光定量PCR技术分析不同外源物质诱导柞蚕蛹血淋巴中溶菌酶基因的表达变化。4个诱导处理组的柞蚕蛹血淋巴均可以产生抑菌活性,但抑菌效果具有显著差异:诱导后72 h柞蚕蛹血淋巴产生明显抑菌效应,抑菌圈直径由小到大依次为无菌水处理组、蛹虫草菌处理组、柞蚕微孢子虫处理组、大肠杆菌处理组,且雌蛹血淋巴的抑菌活性较强。4个诱导处理组柞蚕蛹血淋巴中溶菌酶基因的表达量在诱导后4~8 h内迅速上调,雌蛹和雄蛹中的表达量分别在诱导后24h、8~12 h达到最大,其中,大肠杆菌诱导溶菌酶基因表达上调迅速,但持续时间短,而蛹虫草菌和柞蚕微孢子虫诱导溶菌酶基因的表达量高。研究结果说明柞蚕的免疫应答时间和免疫相关基因的表达水平因诱导源而不同,雌雄个体之间也有差异。 相似文献
865.
866.
Porcine alpha (1,2) fucosyltransferase (FUT2) gene was importance in glycosphingolipid biosynthesis-globo series, potentially played a regulatory role during Escherichia coli (E. coli) F18 infection process in weaned piglets. In order to explore sequence structure of porcine FUT2 gene and its biological function, this test amplified FUT2 gene CDS sequence of Dongchuan pigs by PCR, forecasted and analyzed the protein sequences and functional regions of FUT2 gene, its expression level was detected in 11 tissues of 8 Dongchuan weaned piglets in 35 days old at the meantime. The results showed that the CDS sequence of FUT2 gene was 1 023 bp, which encoded 340 amino acids. FUT2 protein was fat-soluble hydrophilic protein, which the structure was not stable, including a transmembrane helix structure, but without signal peptide that suggested the FUT2 protein was a membrane protein;FUT2 protein included 2 N-glycosylation sites (No. 185 and No. 305 amino acids), without O-glycosylation sites, there were 14 potential phosphorylation sites, included 6 Ser, 2 Thr and 6 Tyr, analyzing the functional regions found that the FUT2 protein had a superfamily of conserved domains:FUT1-FUT2-like (58-319 amino acids). The phylogenetic tree result showed that the relative relationship between swine and cattle was relatively close, but was distant from chimpanzee, human, mouse and rat. FUT2 gene was expressed in all 11 tissues of Dongchuan weaned piglets, there were higher expression in digestive tract and immune tissues. The present results suggested that FUT2 gene might play a role to resistance to E. coli F18 in weaned piglets, and might indirectly against E. coli F18 through the synthesis of fucosyltransferase. 相似文献
867.
介绍选购小型饲料粉碎机应注意的主要事项,总结其安全操作注意要点及保养方式,为确保小型饲料粉碎机的工作性能及安全使用提供参考依据。 相似文献
869.
以鲜葡萄和北虫草菌丝体为主要原料,经正交试验得出北虫草—葡萄补酒的最佳发酵条件为温度25℃,酵母菌种添加量为2%,北虫草菌丝体的添加量为30%,糖度15%,偏重亚硫酸钠添加量为140mg.L-1。北虫草菌丝体在后发酵中加入,得到营养丰富、酒香醇厚、风味独具,具有保健功效的北虫草—葡萄酒补酒。 相似文献
870.