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121.
The Lanyu pig is an indigenous breed from the Lanyu Islet, which is southeast of Taiwan. Two herds of Lanyu pigs were introduced from the Lanyu Islet into Taiwan in 1975 and 1980. The current population of conserved Lanyu pigs consists of only 44 animals with unknown genetic lineage. The Lanyu pig possesses a distinct maternal genetic lineage remote from Asian and European pigs. The present study aimed to understand the phylogenetic relationship among conserved Lanyu, Asian, and European type pigs based on the cytochrome b coding gene, to ascertain the maternal lineage and genetic diversity within the conserved Lanyu pigs, and to address whether genetic introgression from exotic or Formosan wild pigs had occurred in the conserved Lanyu pigs. Entire mitochondrial genomes of both types of Lanyu pig comprised 2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes. Only 2 haplotypes of the mitochondrial DNA (mtDNA) control region and cytochrome b were identified in the conserved Lanyu pig herds. When maximum likelihood trees were constructed, the Type I Lanyu mitochondrial genes formed a unique clade with a large pairwise distance of both cytochrome b and the control region from Asian and European type breeds, Formosan wild pigs, and exotic breeds. Significant loss of genetic diversity of mtDNA within the conserved Lanyu pigs was demonstrated by low haplotype and nucleotide diversities, supported by Fu and Li's D* neutrality test (1.44055; P < 0.05). The mtDNA control region sequences of extant pigs in the Lanyu Islet, however, showed high haplotype and nucleotide diversity, and clustered with exotic pigs. These results indicate no maternal lineage mtD-NA gene introgression from Formosan wild pigs and introduced exotic pigs to conserved Type I Lanyu pigs, and a severe loss of heterozygosity of mtDNA in conserved Lanyu pigs. The remaining extant pigs on the Lanyu Islet have been introgressed with exotic breeds. Strategies for future conservation of native Lanyu pigs are now even more urgent and important.  相似文献   
122.
The endometrium of sheep consists of plenty of raised intercaruncular areas (IC). In order to better understand aglandular areas called caruncular (C), and intensely glandular the endometrium involved mechanisms of implantation, we used LC-MS/MS technique to profile the proteome of ovine endometrial C areas and IC areas separately during the peri-implantation period, and then compared the proteomic profiles between these two areas. We successfully detected 1740 and 1813 proteins in C areas and IC areas respectively. By comparing the proteome of these two areas, we found 170 differentially expressed proteins (DEPs) (P 〈 0.05), functional bioinformatics analysis showed these DEPs were mainly involved in growth and remodeling of endometrial tissue, cell adhesion and protein transport, and so on Our study, for the first time, provided a proteomic reference for elucidating the differences between C and IC areas, as an integrated function unit respectively, during the peri-implantation period. The results could help us to better understand the implantation in the ewes. In addition, we established a relatively detailed protein database of ovine endometrium, which provide a unique reference for further studies.  相似文献   
123.
In order to use rice straw as forage in livestock feeding, the effects of steam-treated rice straw (at 15.5 kgf/cm2 for 120 s) feeding on growth performance, plasma volatile fatty acid profile, and nutrient digestibility of goats were determined. Twenty male goats (18.69?±?0.34 kg) were used in an 84-day trial. The goats were divided into four groups of five goats each to receive steam-treated (STRS) or untreated (UTRS) rice straw diet under closed house (CH) and open house (OH) systems. The results revealed that the goats fed with STRS had significantly higher dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestibility; similarly, the average daily weight gain and feed conversion ratio were higher for STRS groups under both CH and OH systems than those for UTRS. The plasma protein and insulin in STRS and cholesterol in UTRS groups was higher (P?P?>?0.05) at 30 days. The plasma amylase, lipase, T3, T4 and glucagon at 30 and 60 days were not different (P?>?0.05) among the groups. The plasma acetate, propionate, butyrate, and total volatile fatty acid were higher (P?P?>?0.05) on these parameters. It could be concluded that steam treatment of rice straw at 15.5 kgf/cm2 for 120 s increased apparent nutrient digestibility, hence increased the growth and feed efficiency of growing goats.  相似文献   
124.
For investigating the feasibility of using disperse dyes as an immunoassay chromogenic marker, a disperse dye, DADISPERSE NAVY BLUE SP, was selected in analyzing antibody against infectious bursal disease virus (anti-IBDV). With the color intensity revealed in the disperse dye immunochromatographic test (DICT) strip as the objective function, the optimal dyeing conditions were found as follows: dye concentration absorbance (at lambda(max)=587nm)=3, pH 7, 50 degrees C, for 10min. Under these conditions, the resultant dyed-antibody (rabbit anti-chicken) can produce an optimal color intensity reading of 55,054 on the strip. For performing qualitative immunoassay, chicken sera samples taken from different farms were used for the anti-IBDV titre assessment. The results of DICT strips showed very high sensitivity and specificity as compared to that analyzed by FlockChek enzyme linked immunosorbent assay (F-ELISA) kits. For quantitative immunoassay, it was found that the color intensity measured with DICT was linearly correlated to that of F-ELISA titre (r(2)=0.9687). Therefore, DICT was further applied to the detection of chicken anti-IBDV sera under vaccination in the farms. The average titres of the sampling groups exhibited a strong agreement to that of F-ELISA. Accordingly, the DICT method developed in this study, shown to be reliable, cheap and simple in both qualitative and quantitative immunoassays, is particularly suitable for point-of-need testing (PONT) in agricultural applications.  相似文献   
125.
对9周龄蛋用系及快长系五龙鹅血清中GPT及LDH活力进行测定,比较两组鹅间两种酶活力高低,分析酶活力与相应周龄体重的表型相关.结果表明蛋用系与快长系五龙鹅体重存在显著差异(P<0.05),而GPT和LDH活力差异不显著(P>0.05).相关分析发现,两种鹅的GPT和LDH活力与体重无一致的相关性,品系间、公母间结果差异较大,相关不显著.但快长系GPT活力高于蛋用系,蛋用系LDH活力高于快长系;两种酶活力公鹅有高于母鹅的趋势.  相似文献   
126.
对70头山羊、50头绵羊和5头奶山羊进行了人工培植羊黄研究。在植黄后一年,对42头山羊,10头绵羊和1头奶山羊取黄,在羊的胆囊内形成了羊黄。对11个羊黄样品进行了胆色素、总胆固醇和总胆酸等项目测定,结果表明与天然牛黄主要成分相同,但含量有所不同。对5个羊黄样品进行了超微结构观察,结果与天然牛黄一致。 对人工培植羊黄羊的胆囊胆汁进行了测定,β-葡萄糖醛酸苷酶活性(以下简称β-G酶活性)和粘蛋白含量明显升高。因接种的大肠杆菌血清型不同,β-G酶活性也呈现不同程度的变化。对培植羊黄羊的胆囊进行了组织学检查,胆囊壁粘膜上皮柱细胞间的杯状细胞及固有膜中的粘液腺大量增生,是胆汁中多糖粘蛋白增高的组织学基础。 对培植羊黄进行了药理学试验,其结果与天然牛黄完全一样。  相似文献   
127.
Follistatin-like 3 (FSTL3) is a regulator of cellular apoptosis and was previously identified via RNA-Seq to be associated with follicular development in mammalian ovaries. However, the mechanism underlying the FSTL3 regulation of oestrus in sheep remained poorly understood. In this study, the oestrogen (E2) and progesterone (P4) concentrations in blood were detected, and the expression level and functional analysis of FSTL3 in the ovary were studied during the different reproductive stage in Aohan fine wool sheep (seasonal breeding breed in China). The concentrations of E2 and P4 at the anestrus were significantly lower compared to dioestrus, proestrus and oestrus stages. Higher expression levels of FSTL3 were observed in the sheep ovary, hypothalamus, and thyroid. During different reproductive stages, higher expression levels were found during the stages of dioestrus and proestrus, while lower levels were found during the oestrus and anestrus stages. Functional analysis of FSTL3 was performed in primary granulosa cells (GCs) of sheep. The concentration of E2 increased significantly after RNAi interference of FSTL3, while the P4 level decreased. FSTL3 can decrease P4 levels, which might be involved in mediating oestrous cycle in sheep.  相似文献   
128.
猪卵泡液抑制素的分离及其生物活性和免疫活性研究   总被引:3,自引:0,他引:3  
利用SephadexG-200和SephadexG-100二次层析分馏,以标准猪抑制素蛋白和抑制素α-亚单位作参照,结合紫外扫描,分离猪卵泡液抑制素,并测定各组分对HCG诱导的小白鼠生殖器官发育及输卵管水肿抑制的影响和对补体溶血活性的抑制效果,证明可以分离得到生物活性和免疫活性较高的抑制素蛋白组分,其方法较简便,可用于猪卵泡液抑制素的一般制备。  相似文献   
129.
环丙沙星对水产动物气单胞菌的药效学研究   总被引:1,自引:0,他引:1  
环丙沙星为第三代步诺酮类药,是一种安全。高效的抗菌剂。该药对临床分离的几株致病性气单胞菌的最小抑制浓度(MIC)为0.0098μg/ml。人工感染治疗试验表明,该药以1mg/(kg.d)剂量灌服,连用5天,能有效控制鲫鱼败血症的暴发。  相似文献   
130.
为探讨独穴蜂针疗法与蜜蜂毒素对变应性鼻炎的防治效果,5年来采用独穴蜂针疗法治疗了32例全年性变应性鼻炎病人,结果有效率为100%,两年治愈率为78%,说明独穴蜂针疗法对变应性鼻炎具有特殊的防治效果。结果提示:蜂针疗法是一种自然的生物免疫疗法,蜂毒液可能为一类天然的有效的生物应答调节剂,通过调节机体的免疫系统而产生抗过敏、抗感染、抗肿瘤作用。  相似文献   
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