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111.
Guang‐Xin E Wang‐Dui Basang Yan‐Bin Zhu 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(5):371-377
The domestic yak (Bos grunniens) is an iconic symbol of animal husbandry on the Qinghai–Tibet Plateau. Long‐term domestication and natural selection have led to a wide distribution of yak, forming many ecological populations to adapt to the local ecological environment. High altitude is closely related to oxygen density, and it is an important environmental ecological factor for biological survival and livestock production. The aim of the present study was to perform a preliminary analysis to identify the candidate genes of altitude distribution adapted ecological thresholds in yak using next‐generation sequence technology. A total of 15,762,829 SNPs were obtained from 29 yaks with high‐ and low‐altitude distribution by genome‐wide sequencing. According to the results of the selective sweep analysis with FST and ZHp, 21 candidate genes were identified. 14 genes (serine/threonine protein kinase TNNI3K, TEN1, DYM, ITPR1, ZC4H2, KNTC1, ADGRB3, CLYBL, TANGO6, ASCC3, KLHL3, PDE4D, DEPDC1B and AGBL4) were grouped into 32 Gene Ontology terms, and four genes (RPS6KA6, ITPR1, GNAO1 and PDE4D) annotated in 35 pathways, including seven environmental information processing and one environmental adaptation. Therefore, the novel candidate genes found in the current study do not only support new theories about high‐altitude adaptation, but also further explain the molecular mechanisms of altitude adaptation threshold in yaks. 相似文献
112.
北方寒地引种抗寒苜蓿品种试验 总被引:1,自引:0,他引:1
1991、1992年两年对10个抗寒苜蓿品种进行了品种比较试验,鉴选出公农一号、草原一号、草原二号、甘农一号、图牧二号6个苜蓿良种。这些品种适应黑龙江垦区的生态条件,抗寒、抗病性强、长势好、产草量高、品质优良,可以在垦区三江平原推广种植。 相似文献
113.
114.
湖南省根据地理区域和养殖业结构情况,合理布局建立了18个省级动物疫情测报站,通过对测报站辖区内及定点养殖场户的生产、免疫、疫病等情况进行持续跟踪调查和监测采样,评估动物群体免疫状态及疫情发生风险。管理上通过优化网络布局,提高诊断监测能力,通过强化培训和责任管理,提升动物疫情测报水平,确保了动物疫情测报质量。动物疫情测报站在发现新发重大动物疫病,评价强制免疫病种免疫效果,提供疫情预警预报基础数据以及指导养殖业生产等方面发挥了重要作用。今后需持续增加投入和监测科技含量,改善设施设备,稳定技术队伍,这是提高动物疫情测报监测的根本保障。 相似文献
115.
Inhibition of FGF Signalling Pathway Augments the Expression of Pluripotency and Trophoblast Lineage Marker Genes in Porcine Parthenogenetic Blastocyst 下载免费PDF全文
J Zhang Z Li H Zhang L Zhu X Zhu V Verma Q Liu D Shi B Huang 《Reproduction in domestic animals》2016,51(5):649-656
The consistent failure to isolate bona fide pluripotent cell lines from livestock indicates that the underlying mechanisms of early lineage specification are poorly defined. Unlike other species, the contrivances of segregation have been comprehensively studied in the mouse. In mouse, FGF/MAPK signalling pathway dictates the segregation of hypoblast (primitive endoderm). However, it is not evident whether this mechanism is also conserved in livestock. Here, in this study, we examined the roles of FGF/MAP kinase signalling pathways in porcine parthenogenetic embryos during the early development. Porcine parthenogenetic embryos were cultured in the medium addition with FGFR inhibitor BGJ398 (10 μm ) or DEMOS. Pluripotency‐ and lineage‐related gene expressions in the early porcine embryos were determined. Compared to control, total cell numbers on day 7 were significantly higher (55 ± 5.96 vs 47 ± 1.97, p < 0.05) in embryos cultured in the presence of BGJ398, but had no significant effect on the rate of blastocyst development (47% vs 44%, p > 0.05). Nonetheless, BGJ398 treatment significantly augmented the expression of pluripotency and trophoblast marker genes (SOX2, OCT4, KLF4 and CDX2), but did not significantly change the expression of NANOG and hypoblast marker gene (GATA4). Furthermore, the addition of FGF signalling agonist (FGF2) during the embryo development significantly decreased the expression of pluripotency and trophoblast marker genes (SOX2, NANOG, KLF4 and CDX2), but no significant effect on the expression of OCT4 and GATA4 was observed. Here, we exhibit that inhibition of FGF signalling could improve the quality of the porcine embryo and escalate the chance to capture pluripotency. Besides, it also promotes the trophoblast development of porcine parthenogenetic embryo. In addition, the data suggested that FGF signalling pathway is dispensable for the segregation of hypoblast and epiblast lineages in porcine embryo during the early development. 相似文献
116.
117.
Dong-Hui Zhou Fu-Rong Zhao Hui-Yan Xia Min-Jun Xu Si-Yang Huang Hui-Qun Song Xing-Quan Zhu 《Irish veterinary journal》2013,66(1):1-4
Chlamydia spp. are obligate intracellular gram-negative bacteria that cause a wide range of significant diseases in humans and animals worldwide, resulting in significant economic losses. Chlamydial infection in cattle has been reported in many countries including China. However, there has been no survey of chlamydial infection of dairy cattle in Guangzhou, southern China. The objective of the present investigation was to examine the chlamydial seroprevalence in dairy cattle in Guangzhou, subtropical southern China by using an indirect hemagglutination assay (IHA). The overall seroprevalence of chlamydial infection in dairy cattle was 7.25% (29/400). Greater than or equal to eight-yr-old dairy cattle had the highest seroprevalence (10.34%), followed by those that were ≥ 6 years old or < 7 years old dairy cattle (10.20%), although there were no statistically significant differences among different groups (P > 0.05). Dairy cattle with 5 pregnancies had the highest seroprevalence (10.81%). These results indicate that chlamydial infection was present in dairy cattle in Guangzhou, subtropical southern China, and integrated strategies and measures should be executed to control and prevent chlamydial infection and disease outbreak in the study region. 相似文献
118.
为了解正安县山羊主要疫病的发展趋势,通过虎红平板凝集试验、正向间接血凝试验、酶联免疫吸附试验等方法对正安县引进山羊进行布鲁氏杆菌病、O型口蹄疫、AsiaI型口蹄疫、山羊传染性胸膜肺炎、山羊痘等主要疫病血清抗体的检测。结果表明,O型口蹄疫、AsiaI型口蹄疫和山羊痘免疫抗体阳性率分别为79.42%、81.18%和99.58%,未免疫的布鲁氏杆菌病、羊传染性胸膜肺炎的丝状支原体山羊亚种和绵羊肺炎支原体未免疫抗体阳性率分别为0%、0%和3.81%。监测结果为山羊健康的引进、培育和扩繁提供了一些基础数据,对指导养羊生产有一定的意义。 相似文献
119.
Comparative expression profile of microRNAs and piRNAs in three ruminant species testes using next‐generation sequencing 下载免费PDF全文
microRNA (miRNA) and piwi‐interacting RNA (piRNA) are two classes small non‐coding regulatory RNAs that play crucial roles in multiple biological processes such as spermatogenesis. However, there are no published studies on conjoint analysis of miRNA and piRNA profiles among cattle, yak and their interspecies (the dzo) using sequencing technology. Next‐generation sequencing technology was used to profile miRNAs and piRNAs among those three ruminants to elucidate their functions. A total of 119, 14 and six differentially expressed miRNAs were obtained in cattle vs. dzo, cattle vs. yak and yak vs. dzo comparison groups, while there were 873, 1,065 and 1,158 differentially expressed piRNAs in those three comparison groups. The expression of three miRNAs was validated in the three ruminants, and the results suggested that the miRNA expression profiles data could represent actual miRNA expression levels. Moreover, the putative targets of differentially expressed miRNAs were predicted by their own genome, it is worth to note that both the cattle and yak genome were used for dzo, then the targets were subjected to GO enrichment and KEGG pathway analysis, revealing the likely roles for these differentially expressed miRNAs in spermatogenesis. In conclusion, this study provided a useful resource for further elucidation of the miRNAs and piRNAs regulatory roles in spermatogenesis. It may also facilitate the development of therapeutic strategies for dzo reproduction research. 相似文献
120.
披碱草属四种植物主要形态特征的变异性比较 总被引:2,自引:1,他引:2
应用变异系数、主成分分析、系统聚类分析方法,对披碱草属四种不同生境来源的18个居群的180份材料进行形态特征比较分析.变异系数分析结果表明:(1)披碱草属4种植物的不同居群在形态特征上具有变异性;(2)不同居群内及居群间的形态特征存在一定程度的变异;(3)穗部形态特征中的颖及稃特征是种间和种以下分类的重要依据.主成分分析结果表明:颖长、颖脉数、外稃长、内稃长、小穗长、小穗宽等是种间分类的重要特征指标.系统聚类分析法分析表明:在欧式距离等于5时可将来自不同生境的18个居群分为3类,经鉴定第一类为披碱草和老芒麦,第二类为麦宾草,第三类是圆柱披碱草;其中麦宾草的归类清晰. 相似文献