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91.
应用单引物PCR指纹技术分析Vc-獭兔的分子遗传结构 总被引:2,自引:0,他引:2
采用1条小卫星引物M13(5’GAGGGTGGCGGTTCT3’)和2条微卫星引物(GTG)5、(GACA)4,对Vc—Ⅰ系、Vc—Ⅱ系獭兔、日本大耳白兔(JWR)和青紫蓝(QZL)4个品系各8只,总计32个个体的遗传结构进行了DNA指纹分析。结果,3条引物的扩增产物都呈现良好的多态性和稳定性;对每个品系混合DNA池进行分析,计算出了4个品系间及32个个体间的共有带率及遗传距离指数,通过聚类分析,得出各品系间和个体间欧式遗传距离,并绘制出4个品系间及各品系32个个体问的亲缘关系树状聚类图,从而初步建立了4个品系兔的SPAR指纹图谱。 相似文献
92.
鲁西牛的染色体研究 总被引:1,自引:0,他引:1
研究了40头鲁西牛(♂37,♀3,2n=60)染色体的 G 带,R 带,C 带及Ag-NOR,着重分析了 y 染色体的形态及带型。在常规 Giemsa 染色的分裂相上,y染色体和小的常染色体形态相近。经常规—C 带连续染色,准确识别出 y 染色体之后测量了18条 y 染色体,臂比为3.19,属亚端着丝点染色体。y 染色体的着丝点区和短臂与常染色体的着丝点区和短臂在 G 带、C 带的带型上差别很大,表明构成它们 DNA的硷基成份有差别。统计的152个细胞的 Ag-NOR 中,平均每细胞 Ag-NOR 数为5.81±1.38,变化范围2—9。按染色体长度排列,NOR 位于2、3、4、11、22(或21)和28号常染色体末端。第22(或21)号染色体上存在 NOR 在其它牛种上尚未有过报道。 相似文献
93.
豆科牧草追施钾肥试验 总被引:5,自引:0,他引:5
试验结果表明,当旱地红壤养分中的速效钾含量在75.5ppm情况下,白三叶每公顷追施氯化钾225kg,结果施肥比对照每公顷增产鲜草7779kg,每公顷氯化立鲜草34.6kg,增产率达29%。按生物统计t测验,增产显著。当稻田速效钾含量在45ppm条件下,给紫云英每公顷施用氯化钾112.5kg,结果施肥比对照每公顷增产鲜草5000-7750kg,平均每公顷增产6750kg。每公斤钾肥可增产粮食23.5 相似文献
94.
95.
Jianning He Qiuyue Liu Shunyu Yu Mengyuan Lei Jifeng Liu Ran Di Zhaojia Ge Wenping Hu Xiangyu Wang Nan Liu Mingxing Chu 《Reproduction in domestic animals》2021,56(3):427-436
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
96.
Ming Qin Wei Chen Zhixin Li Lixue Wang Lixia Ma Jinhong Geng Yu Zhang Jing Zhao Yongqing Zeng 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(3)
BackgroundInterferon lambda receptor 1 (IFNLR1) is a type II cytokine receptor that clings to interleukins IL-28A, IL29B, and IL-29 referred to as type III IFNs (IFN-λs). IFN-λs act through the JAK-STAT signaling pathway to exert antiviral effects related to preventing and curing an infection. Although the immune function of IFN-λs in virus invasion has been described, the molecular mechanism of IFNLR1 in that process is unclear.ObjectivesThe purpose of this study was to elucidate the role of IFNLR1 in the pathogenesis and treatment of porcine reproductive and respiratory syndrome virus (PRRSV).MethodsThe effects of IFNLR1 on the proliferation of porcine alveolar macrophages (PAMs) during PRRSV infection were investigated using interference and overexpression methods.ResultsIn this study, the expressions of the IFNLR1 gene in the liver, large intestine, small intestine, kidney, and lung tissues of Dapulian pigs were significantly higher than those in Landrace pigs. It was determined that porcine IFNLR1 overexpression suppresses PRRSV replication. The qRT-PCR results revealed that overexpression of IFNLR1 upregulated antiviral and IFN-stimulated genes. IFNLR1 overexpression inhibits the proliferation of PAMs and upregulation of p-STAT1. By contrast, knockdown of IFNLR1 expression promotes PAMs proliferation. The G0/G1 phase proportion in IFNLR1-overexpressing cells increased, and the opposite change was observed in IFNLR1-underexpressing cells. After inhibition of the JAK/STAT signaling pathway, the G2/M phase proportion in the IFNLR1-overexpressing cells showed a significant increasing trend. In conclusion, overexpression of IFNLR1 induces activation of the JAK/STAT pathway, thereby inhibiting the proliferation of PAMs infected with PRRSV.ConclusionExpression of the IFNLR1 gene has an important regulatory role in PRRSV-infected PAMs, indicating it has potential as a molecular target in developing a new strategy for the treatment of PRRSV. 相似文献
97.
通过盆栽试验研究包膜氮肥配施不同用量钾肥对多年生黑麦草(Lolium perenne)生长特性及产量的影响,以期明确适宜黑麦草生长的最佳施肥配比。结果表明,与普通尿素相比,包膜氮肥显著提高了黑麦草植株SPAD值、株高、叶面积、净光合速率(P <0.05),明显延长了黑麦草绿期,防止早衰。施用等量钾肥条件下,包膜氮肥处理比普通尿素处理4次刈割的SPAD值分别提高11.2%、 6.9%、 33.6%和195.2%,株高分别增加14.1%、 6.0%、 25.1%和85.4%。包膜氮肥处理较普通尿素处理的干草产量提高了12.4%~25.0%。包膜氮肥配施中量钾肥处理能最大程度增加叶面积指数和净光合速率,提高黑麦草产量,因此推荐作为最佳施肥配比,为黑麦草的氮钾肥合理施用提供理论依据。 相似文献
98.
Moazenijula G Jabbari AR Geravand MM Banihashemi R Hajizadeh A 《Tropical animal health and production》2011,43(8):1471-1474
The anaphylactic reactions in cattle following leptospira vaccination mostly booster dose in different parts of Iran have
been reported. The serum proteins as allergic substances are components of liquid phase of the vaccine. Therefore, the vaccine
was modified by washing the whole cultures by centrifugations. The modified vaccine was safe in laboratory animals and cattle
as well as under field conditions. Microagglutination test revealed a similar pattern of antibody response to the three Leptospira interrogans serovars (Canicola, Grippotyphosa, and Sejro hardjo) in all vaccinated cattle groups while was higher than the response of
control animals. The results of the present investigation revealed that we can minimize postvaccination shock in vaccinated
cattle populations with removing the shock proteins. 相似文献
99.
Ba A Lesnoff M Poccard-Chapuis R Moulin CH 《Tropical animal health and production》2011,43(6):1101-1109
The herds of 95 families were monitored for 1 year in eight villages in the cotton-growing region of southern Mali. In 2006–2007,
reproduction performances were average, with 0.54 calvings/year per cow, and mortality was low. Herd numerical productivity
is not very high, less than 0.13/year, because of the high proportion of males kept for animal draught. Depending on the herd
size, the behaviour of the families differs, in terms of off-take and in-take of animals. Families that only have one or two
draught animals seek to increase their animal draught capacity, with a negative net off-take (−0.13/year). Families with two
to three cows have a very low net off-take (0.02/year), with culling of adult animals compensated by purchase. They therefore
capitalised this year, with an annual herd growth of 8%. Families with a very large herd (20 to 50 cows) take off more of
their stock, with a net off-take of 0.08/year (very few animal purchases) and make a stock growth of 5%. And finally, families
with an average-sized herd (6 to 19 cows) take off the whole of the year’s production, with a net off-take of 0.11/year and
a nil stock growth rate. The use of a demographic model made it possible to measure the sensitivity of the productivity rate
to the different demographic parameters. 相似文献
100.
用MTT法测定了藏菖蒲、红景天、决明子、灵芝盖、灵芝柄、龙胆、天冬、降香、乳香、仁青芒觉、二十五味珍珠丸、二十五味松石丸等12种藏药对体外培养的鸡胚成纤维细胞(CEF)的安全浓度和生长的影响.结果显示,各藏药的最大安全质量浓度红景天为31.25 mg/L,天冬、降香、决明子和二十五味松石丸为62.5 mg/L,乳香为125mg/L,二十五味珍珠丸为250 mg/L,藏菖蒲和灵芝柄为1 000 mg/L,龙胆和仁青芒觉为2 500 mg/L,灵芝盖为5 000 mg/L,藏菖蒲为1.954~500 mg/L,天冬为1.954~15.625 mg/L,决明子为1.954~3.907 mg/L,灵芝柄为1.954~7.813 mg/L,仁青芒觉为19.54~1 250 mg/L,龙胆为312.5~625 mg/L,可显著促进细胞生长. 相似文献