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101.
旨在通过对奶绵羊产奶性状的全基因组关联分析(GWAS),寻找和定位与奶绵羊产奶性状相关的遗传标记和功能基因。本研究以135只戴瑞奶绵羊为试验材料,基于全基因组重测序技术,通过SAMTOOLS进行单核苷酸多态性(SNP)检测,使用PLINK v1.90进行质控,利用GEMMA v 0.98.1的混合线性模型对质控结果进行奶绵羊产奶性状相关的全基因组关联分析。结果表明,有1个SNP与泌乳后90天日均产奶量在全基因组范围内显著相关,8个SNPs达到潜在显著关联,相关的候选基因包括TRNAQ-CUG-2、LOC114117240、ACADL、MYL1、CHD6、SLCO3A1;有2个SNPs与150天日均产奶量达潜在显著关联,相关的候选基因包括PRMT6、RNF180;有2个SNPs与泌乳周期达潜在显著关联,相关的候选基因包括PRMT6、TRNAW-CCA-68、TRNAS-GGA-61。进一步基因功能分析推测,ACADL、SLCO3A1可能是影响奶绵羊产奶性状的候选基因。本研究为奶绵羊产奶性状的分子机制解析提供了一定的基础,为我国奶绵羊新品种培育提供了一定的理论参考。 相似文献
102.
Mingli LIN Mingming LIU Francesco CARUSO Massimiliano ROSSO Xiaoming TANG Lijun DONG Wenzhi LIN Anna BORRONI Alessandro BOCCONCELLI Liang DAI Songhai LI 《Integrative zoology》2021,16(4):440-450
A pioneering boat-based survey was conducted in 2019, to gather baseline information regarding the presence, composition, relative abundance, and spatial distribution of deep-diving and off-shore cetaceans in the northern South China Sea (SCS). A total of 27 sightings comprising at least 8 cetacean species were recorded during the 13-day survey, including 5 deep-diving species (i.e. Risso's dolphin [Grampus griseus], short-finned pilot whale [Globicephala macrorhynchus], sperm whale [Physeter macrocephalus], Cuvier's beaked whale [Ziphius cavirostris], and an unidentified beaked whale [either the ginkgo-toothed beaked whale, Mesoplodon ginkgodens, or Deraniyagala's beaked whale, Mesoplodon hotaula]), as well as 3 off-shore dolphins (i.e. pantropical spotted dolphin [Stenella attenuate], striped dolphin [Stenella coeruleoalba], and Fraser's dolphin [Lagenodelphis hosei]). With the exception of pantropical spotted dolphins, all other species were sighted and recorded at sea in the northern SCS for the first time. The pantropical spotted dolphin was the most frequently sighted species, comprising 30% of the total sightings. Deep-diving cetaceans were mainly sighted in the northern Xisha Archipelago, whereas off-shore dolphins were distributed across the survey area. The pantropical spotted dolphin was observed in aggregations of more than 100 individuals and nearly all encountered species included calves; these findings suggested that the survey area functions as an important feeding and calving ground for various cetacean species. This pioneering survey provides fundamental information regarding cetacean fauna in the northern SCS and highlights the need to strengthen research and conservation efforts concerning these species. 相似文献
103.
Chengquan Tan Yongcheng Ji Xichen Zhao Zhongquan Xin Jiaying Li Shuangbo Huang Zhiying Cui Lijun Wen Caihua Liu Sung Woo Kim Jinping Deng Yulong Yin 《动物营养(英文)》2021,7(1):111
Increased metabolic burdens in breeding sows, which are induced by elevated systemic oxidative stress, could increase the need for nucleotides to repair lymphocyte DNA damage; however, de novo synthesis of nucleotides may be insufficient to cover this increased need. This study investigated the effects of dietary nucleotides on milk composition, oxidative stress status, and the reproductive and lactational performance of sows. Forty multiparous sows were assigned to 2 dietary treatments (Control group, and 1 g/kg Nucleotides group) based on a randomized complete block design using their BW at 85 d of gestation as a block. Sows from 2 groups were fed a restricted diet during gestation and ad libitum during lactation. The experiment lasted from 85 d of gestation to 21 d of lactation. The reproductive performance of sows and the growth performance of suckling piglets were measured. Oxidative stress parameters and milk components were also analysed. Data were analyzed using contrasts in the MIXED procedure of SAS. Sows in the Nucleotides group consumed more feed during the first week (P < 0.01) and from 1 to 21 d (P < 0.05) of lactation than those in Control group. Correspondingly, the litter weight gain of piglets showed a tendency to increase from cross-fostering to 9 d (P = 0.09) and from cross-fostering to 20 d (P = 0.10) in the Nucleotides group relative to the Control group. Additionally, the Nucleotides group was higher (P < 0.01) than the Control group in the concentrations of uridine 5''monophosphate, guanosine 5''monophosphate, inosine 5''monophosphate, adenosine 5''monophosphate and total nucleotides in milk. Furthermore, the Nucleotides group was higher (P < 0.01) than the Control group in the serum levels of total antioxidant capacity (P < 0.01) for sows at 109 d of gestation and glutathione peroxidase for weaning piglets, but lower at the levels of thiobarbituric acid-reactive substances (P < 0.05) in serum of weaning piglets. This study indicated that maternal dietary nucleotides could promote piglet growth, probably due to the higher lactational feed intake and higher concentration of nucleotides in the milk of sows, and lower oxidative stress for both sows and piglets. 相似文献
104.
水生态环境遭到不同程度的破坏,流域健康状况越来越受到重视。水基系统的提出为流域健康评价提供了新的理论框架。现以挠力河流域为研究基点,根据其国家农产品主产区的特点,在水基系统的理论框架下,研究了适合该流域的健康评价等级标准,并依据指标选取5项原则、流域的自然经济状况构建了挠力河流域的水基系统健康评价指标体系。筛选了以农业生产和可持续发展为主导的评价指标集,分析了特定指标对该研究区域的适用性。所建立水基系统健康评价体系和指标集可为挠力流域的可持续发展提供技术支持。 相似文献
105.
106.
小型猪近交系新品种的培育与开发利用 总被引:1,自引:0,他引:1
小型猪近交系是中国农业科学院北京畜牧兽医研究所以2头五指山猪(Sus scrofa)为系祖,历时15年,采用“近亲交配”、提高营养水平、同期发情以及笼架等饲养技术,逐步克服后代畸形率高、弱仔率高、成活率低等3大阶段性难题,育成国际上首个近交系猪.本文介绍小型猪近交系的培育过程、近交系研究鉴定、新遗传资源种质特性,以及开发利用.该研究成果填补了国内外近交系猪的研究空白,为大型哺乳近交系动物培育理论和应用研究提供了新的视角. 相似文献
107.
ZHANG Hai ZHOU Bi-jun YANG Zhong-cheng LIAO Mei WANG Kai-gong WEN Ming CHENG Zhen-tao WANG Wei FENG Xu-fang 《中国畜牧兽医》2016,43(11):2834-2843
In order to study and analyze L1 gene of bovine papillomavirus(BPV)in Guizhou province,the L1 gene of BPV-GZ01 strain was amplified,cloned and sequenced using bioinformatic softwares and methods,and the secondary structure,tertiary structure,B-cell preponderant epitope,conserved domains analysis, transmembrane domain and signal peptide of L1 gene were predicted.The results showed that the length of L1 gene was 1 494 bp,encoding 497 amino acids.The L1 gene of BPV-GZ01 strain shared an amino acid identities of 98.6%,99.4%,98.4%,94.4% and 91.3%,and a nucleotide identities of 99.1%,99.8%,99.4%,87.6% and 82.8% with those of BPV2,BPV2-SW01,BPV2-AKS01,BPV13 and BPV1 strains,respectively.The results of phylogenetic tree analysis indicated that there was a close relationship between BPV-GZ01 and BPV2-SW01 strains.The prediction of secondary structure of L1 protein indicated that the random coil,extended strand and alphahelix took a higher percentage.The L1 protein was supposed contain 6 potential antigen epitopes.And no transmembrane domains and no signal peptide were found.The tertiary structure of L1 protein was curved spiral structure.These results provided a theoretical basis for immunologic diagnosis and further research of nucleic acid vaccine of BPV. 相似文献
108.
YAO Wei YU Xue-wu CAO Dong ZHAO Xiao-tong GU Gui-bo CHEN Yao ZHANG Lei LIU Yao-chuan FENG Jun-ke 《中国畜牧兽医》2016,43(11):3080-3084
In order to understand the main bacterial pathogen species causing dairy cow mastitis in Liaoning, as well as the characteristics of drug sensitivity of the pathogenic E.coli,the milk samples from 75 dairy cows with clinical manifestations for mastitis in certain large-scale dairy farm in Liaoning were collected.The bacteria in milk were cultured and isolated with biochemical methods and in vitro drug sensitivity tests were processed with the isolated E.coli strains.The results showed that the main bacterial pathogen for dairy cow mastitis were E.coli(separation rate 58.7%),S.aureus(64.0%)and S.agalactiae(54.7%),and multiple infection including double and triple infection were identified.The drug sensitivity tests on the isolated E.coli indicated that the E.coli isolates were highly resistant to sulfonamides(resistance rate>85%)and chloramphenicol(resistance rate>30%),and they were relatively low resistant to ampicillin(9.5%),ciprofloxacin(9.5%),ceftiofur(7.1%)and ofloxacin(4.8%).The results was able to provide reliable theoretical basis for prevention and control of dairy cow mastitis in Liaoning area. 相似文献
109.
110.
以"赤霞珠"葡萄为试材,对组培快繁中的取材部位、消毒方法、不同激素用量、是否带叶继代培养等关键技术措施进行了研究探讨。结果表明:以半木质化,0.1%升汞溶液消毒8min的茎段接种,成活率高,污染率低;并且继代培养和生根培养最好的培养基为1/2MS+IBA0.2mg·L~(-1)+蔗糖20g·L~(-1)+琼脂7g·L~(-1)。 相似文献