The roles of calving migration and climate change in the formation of the weak genetic structure in the Tibetan antelope (Pantholops hodgsonii)

Geographical barriers and distance can reduce gene exchange among animals, resulting in genetic divergence of geographically isolated populations. The Tibetan antelope (Pantholops hodgsonii) has a geographical range of approximately 1600 km across the Qinghai–Tibet Plateau, which comprises a series of tall mountains and big rivers. However, previous studies indicate that there is little genetic differentiation among their geographically delineated populations. To better understand the genetic structure of P. hodgsonii populations, we collected 145 samples from the 3 major calving regions, taking into consideration their various calving grounds and migration routes. We used a combination of mitochondrial sequences (Cyt b, ATPase, D‐loop and COX I) to investigate the genetic structure and the evolutionary divergence of the populations. Significant, albeit weak, genetic differentiation was detected among the 3 geographical populations. Analysis of the genetic divergence process revealed that the animals gradually entered a period of rapid genetic differentiation approximately 60 000 years ago. The calving migration of P. hodgsonii cannot be the main cause of their weak genetic structure because this cannot fully homogenize the genetic pool. Instead, the geological and climatic events as well as the coupling vegetation succession process during this period have been suggested to greatly contribute to the genetic structure and the expansion of genetic diversity.     

冀东滨海平原稻区土壤钾库状况与变化

通过对大面积土壤各形态钾的定位监测,研究了1982～2016年30余年间冀东滨海平原稻区土壤钾库的现状、变化及其影响因素,分析了成土母质、耕种施肥等对该区域土壤钾库的影响。主要结果:(1)冀东滨海平原稻区土壤全钾、缓效钾、速效钾平均含量分别为23.04 g/kg、1 615.94 mg/kg、247.37 mg/kg。种稻40～70余年间,各年限土壤全钾、速效钾分别维持在23.96 g/kg、257.41 mg/kg左右。与种稻40年相比,缓效钾年均减少20.19 mg/kg。(2)不同母质土壤全钾、缓效钾、速效钾含量大小顺序为:海相沉积物、泻湖沉积物河流冲积物;土壤缓效钾/全钾和速效钾/全钾均为海相沉积物、泻湖沉积物河流冲积物,3种母质发育的土壤速效钾/缓效钾差异不显著;海相沉积物、泻湖沉积物二者之间的各形态钾含量及比值均无显著差异。(3)土壤速效钾与土壤盐分、有机质均呈显著正相关关系;土壤速效钾与有效磷无显著相关关系。主要结论:随种植年限增加,土壤全钾、速效钾无显著变化,缓效钾显著下降。海相沉积物、泻湖沉积物发育的土壤全钾、缓效钾、速效钾的含量均显著高于河流冲积物,土壤速效钾与盐分呈显著正相关关系。稻区土壤钾输入量小于水稻钾的输出量,随着种稻年限的增加,逐渐消耗土壤缓效钾。     

冷应激对新疆阿勒泰羊脂蛋白脂酶mRNA表达的影响

为研究冷应激对阿勒泰羊脂蛋白脂酶(lipoprotein lipase,LPL)mRNA表达的影响,试验分别采集冷应激前与冷应激后阿勒泰羊6个部位的组织,采用实时荧光定量PCR方法检测各组织中LPL mRNA的表达水平,分析其在不同部位中表达的变化.结果显示,阿勒泰羊LPL mRNA表达量在冷应激后显著或极显著升高(P<0.05;P<0.01),其中颈部肌间脂肪和尾部脂肪冷应激后表达量最高.表明阿勒泰羊在低温下脂肪组织的动员能力较强,使机体产热增加,以抵抗冷应激.     

宁夏部分地区牛病毒性腹泻的血清学检测

[目的]掌握宁夏地区部分牛场犊牛病毒性腹泻病毒感染情况,为犊牛病毒性腹泻的净化和综合防治提供依据。[方法]从宁夏4个市9个县(区)的25个发病牛场(户)采集血清样品191份,采用ELISA方法,进行血清学调查。[结果]宁夏4个地级市犊牛病毒性腹泻的抗体阳性率高达64.92%,并有一定程度的抗原阳性,且主要发生在1月龄以内的犊牛。[结论]牛病毒性腹泻是具有重大经济意义的疾病,是今后宁夏养牛业应重点防范的疾病之一。     

猪流感病毒A/swine/Guangdong/2/2012(H1N1)毒株攻毒BALB/c小鼠细胞因子动态变化的研究

为了测定H1N1亚型猪流感病毒(swine influenza virus,SIV)对小鼠的致病性,本试验对A/swine/Guangdong/2/2012(H1N1)株SIV HA基因进行克隆及遗传分析,并将SIV尿囊液经鼻腔感染6周龄BALB/c小鼠,观察感染后小鼠的一般状况、器官系数和组织病理学变化,在病毒感染后第1、3和7天使用荧光定量PCR测定小鼠肺脏、脾脏、脑组织中7种细胞因子mRNA的表达量,研究其对小鼠的致病特性。结果显示,该病毒属于经典SIV,病毒经鼻腔感染后可引起小鼠活动减少、采食量降低,但无咳嗽和死亡;病理组织学变化为肺间隔较正常组织明显增厚,毛细血管明显扩张充血,周围肺泡腔呈代偿性肺气肿;小鼠肺脏、脾脏组织样本中IFN-α、IFN-β、IP-10、IL-1β、TNF-α、IRF-3和IL-10 mRNA含量在感染后第3天均显著升高(P<0.05),而脑组织样本中IL-1β和IL-10在小鼠攻毒后第3和7天均显著上调(P<0.05)。     

北大营示范场黑麦草引种与品比试验研究

利用1998年2－11月在云南省北大营示范场引种的10个黑麦草品种的观测资料，统计分析了在高、中、低3种施肥水平下黑麦草的累计产量、月平均产量及其生长速度的变化规律，研究了影响产量的主导因子及其监测模型。结果表明，在10个品种中，伯生（Bison Intermdiate）及安巴瑟（Embassy）具有良好的生产性能。黑麦草产量主要受气候、土壤肥力及品种等因素的影响，其中测草盘高度、降水量、蒸发量、日照时数和牧草生长天数等5个因子，可以较好地模拟、评估黑麦草产量的变化动态。     

Effects of dietary lipid levels on lipid deposition and activities of lipid metabolic enzymes in hybrid tilapia (Oreochromis niloticus × O. aureus)

This study was designed to investigate the effects of dietary lipid levels on growth performance, lipid deposition and activities of lipid metabolic enzymes in hybrid tilapia (Oreochromis niloticus × O. aureus). Four isonitrogenous (300 g/kg crude protein) experimental diets containing graded levels of lipid (25, 55, 85 and 115 g/kg) were randomly assigned to triplicate groups of 180 juvenile fish. Fish were fed twice daily for 8 weeks. At the end of the experiment, the growth performance and proximate composition of fish were determined. The activities and gene expression of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) were assessed as well. Fish fed the diets with 55 and 85 g/kg lipid had a significantly (p < 0.05) higher body weight gain than those fed the diets with 25 and 115 g/kg lipid. The whole-body and liver lipid contents were significantly (p < 0.05) elevated with increasing dietary lipid levels. Moreover, the activities and mRNA abundances of LPL and HSL in the liver, dorsal muscle and fat tissues were markedly altered by dietary lipid levels. Our data demonstrate a profound influence of dietary lipid levels on the growth and lipid deposition in hybrid tilapia, which is likely associated with the regulation of lipid metabolic enzymes including LPL and HSL.     

颈静脉灌注不同模式的氨基酸混合物对泌乳奶牛乳蛋白合成的影响

本试验旨在比较颈静脉灌注酪蛋白模式和理想模式的氨基酸混合物对泌乳中期荷斯坦奶牛乳产量、乳成分以及乳腺对氨基酸摄取利用的影响。选择8头泌乳中期[泌乳天数:(82±11)d]荷斯坦奶牛作为试验动物,试验采用随机区组设计,将试验牛随机分为2组,分别颈静脉灌注160g/d酪蛋白模式(Casein组)和理想模式的氨基酸混合物(R组)。2个试验组分别以各自灌注前作为空白对照组(C1组为Casein组的空白对照组,C2组为R组的空白对照组)。预试期14d,灌注期5d。试验采用全混合日粮(TMR)饲喂,以玉米、豆粕、棉籽粕、玉米青贮、苜蓿干草和羊草为主要原料,参照NRC(2001)奶牛饲养标准配制。结果表明:灌注酪蛋白模式的氨基酸混合物后,乳蛋白产量和含量较灌注前呈上升趋势(乳蛋白产量上升7.14%,P=0.078;乳蛋白含量上升3.27%,P=0.072);并且,奶牛动脉血浆中异亮氨酸(Ile)、亮氨酸(Leu)、赖氨酸(Lys)和组氨酸(His)的浓度较灌注前有不同程度的上升(Ile的浓度提高31.5%,P=0.097;Leu的浓度提高65.9%,P=0.041;Lys的浓度提高36.9%,P=0.088;His的浓度提高40.1%,P=0.010),而苏氨酸(Thr)、缬氨酸(Val)、蛋氨酸(Met)、苯丙氨酸(Phe)和精氨酸(Arg)的浓度在数值上虽较灌注前高但无显著差异(P0.05)。灌注酪蛋白模式的氨基酸混合物后,奶牛乳腺对天冬氨酸(Asp)和半胱氨酸(Cys)的摄取率显著升高(Asp的摄取率提高95.2%,P=0.031;Cys的摄取率提高49.6%,P=0.031),而奶牛乳腺对甘氨酸(Gly)的摄取率显著降低(降低158.3%,P=0.041)。灌注理想模式的氨基酸混合物后,乳蛋白含量比灌注前有上升趋势(提高5.78%,P=0.064),而乳脂产量显著低于灌注前(降低8.57%,P=0.015);并且,奶牛动脉血浆中Arg的浓度有上升趋势(提高18.0%,P=0.093),而酪氨酸(Tyr)的浓度呈下降趋势(降低47.8%,P=0.074)。灌注理想模式的氨基酸混合物后,奶牛乳腺对谷氨酸(Glu)、Cys和Ile的摄取率显著上升(Glu的摄取率提高118.7%,P=0.015;Cys的摄取率提高77.4%,P=0.032;Ile的摄取率提高46.0%,P=0.012),而奶牛乳腺对Ser的摄取率呈下降趋势(降低56.2%,P=0.052)。灌注氨基酸混合物后,Casein组乳脂产量增量显著高于R组(P=0.012),且Casein组的乳产量增量(P=0.095)和乳糖产量增量(P=0.091)较R组有升高的趋势,而2组间其他指标增量无显著差异(P0.05)。由此得出,在本试验条件下,颈静脉灌注酪蛋白模式和理想模式的氨基酸混合物均可提高泌乳奶牛的乳蛋白含量,而灌注酪蛋白模式氨基酸混合物同时可以促进乳蛋白产量的升高,因此,颈静脉灌注酪蛋白模式氨基酸混合物的效果优于灌注理想模式氨基酸混合物。     

Testing and Identification of Carp Edema Virus Disease in Cultured Koi

An acute infectious diseases occurred in a koi farm in Fangshan district, Beijing, and it resulted in mortalities of more than 50%.The main symptoms of sick koi were gills necrosis, kidney erosion and edema,which were similar to the clinical signs of koi herpes virus disease (KHVD).But PCR tests showed negative results for KHV. For further diagnosis, bacterial cultures, transmission electron microscopy studies, virus isolation and PCR tests were used. Electron microscopic observation revealed pox virus particles having a size of about 200 nm×400 nm in the kidney. 548 and 180 bp fragments were amplified from organs of sick koi by PCR method using specific primers of carp edema virus (CEV). The fragments were sequenced and analysed. The results showed that they were shared 100% nucleotide identity with CEV-H504. All the results indicated that this disease was carp edema virus disease, caused by a kind of pox virus, CEV. This was the first report on the CEV of cultured koi in China.     

21个小麦品种(系)抗叶锈性基因推导

选用１７个小麦叶锈菌菌系对１９９９扑河北省使用的２１个小麦品种（系）进行了抗叶锈性基因的推导。通过与２１个抗叶锈单基因系的反应型比较,鉴定出Ｌｒ１、Ｌｒ１４ａ、Ｌｒ２６和Ｌｒ３７等４个抗叶锈基因。８９０４含有Ｌｒ１;５１０８和４１８５可能含有Ｌｒ１或含与Ｌｒ１不同的抗性基因;中麦９号含有Ｌｒ１４ａ及其它抗性基因;８４２５１、邯郸４５６４、７１－３、梁麦２、７１１８－８、８５９－３４、８５９－３９和矮三共８个品种（系）含有Ｌｒ２６抗性基因;２６３１、北农８、鲁麦２３、高优５０３、９７－１１、益麦１含有与供试的已知基因不同的抗性基因;冀麦３８、京３８和３１８１没有鉴定出抗叶锈基因。