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亚热带牧用草地中威提特东非狼尾草的种子繁殖研究 总被引:4,自引:0,他引:4
在3月和4月对全日制放牧的东非狼尾草草地上的风干牛粪取样,进行发芽试验,分别测定其中的东非狼尾草发芽种子数量。结果,3月取样平均432.5 g的牛粪中东非狼尾草平均发芽种子数量为118.25粒,4月取样平均437.8 g的牛粪中东非狼尾草平均发芽种子数量为52.8粒,二者平均牛粪重为435.15 g,平均发芽种子为85.5粒,说明牛粪中东非狼尾草种子数量较多,是其繁殖扩展较快的主要原因;3月取样的种子数量为4月取样数量的1.38倍,说明人工利用牛粪进行东非狼尾草繁殖时,需在有降雨来临前准备,即1~3月进行牛粪的准备工作。 相似文献
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Expression dynamics of bovine MX genes in the endometrium and placenta during
early to mid pregnancy
Takahiro SHIROZU Keisuke SASAKI Manabu KAWAHARA Yojiro YANAGAWA Masashi NAGANO Nobuhiko YAMAUCHI Masashi TAKAHASHI 《The Journal of reproduction and development》2016,62(1):29-35
MX belongs to a family of type I interferon (IFN)-stimulated genes, and the MX protein has
antiviral activity. MX has at least two isoforms, known as MX1 and
MX2, in mammals. Moreover, bovine MX1 has been found to have alternative
splice variants—namely, MX1-a and MX1B. In ruminants, IFN-τ—a type I IFN—is
temporarily produced from the conceptus before implantation and induces MX expression in the
endometrium. However, the expression dynamics of MX after implantation are not clear. In the
present study, we investigated the expression of MX1-a, MX1B and
MX2 in the endometrium and placenta before and after implantation along with the expression
of IFN-α, type I receptors (IFNAR1 and IFNAR2) and
interferon regulatory factors (IRF3 and IRF9). Pregnant uterine samples were
divided into five groups according to pregnancy days 14–18, 25–40, 50–70, 80–100, and 130–150. Tissue samples
were collected from the intercaruncular endometrium (IC), caruncular endometrium (C) and fetal placenta (P).
Although all the MX expressions were significantly higher in the IC and C at days 14–18,
presumably caused by embryo-secreted IFN-τ stimulation, their expressions were also detectable in the IC, C
and P after implantation. Furthermore, IFN-α expression was significantly higher in the IC.
RT-PCR indicated IFNAR1, IFNAR2, IRF3 and
IRF9 mRNA in all the tissues during pregnancy. These results suggest that all the
MX genes are affected by the type I IFN pathway during pregnancy and are involved in an
immune response to protect the mother and fetus. 相似文献
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对张家口市奶牛场进行了奶牛乳腺炎调查并对25头患有急性乳腺炎奶牛的64个乳区64份乳样进行细菌分离与鉴定,共分离葡萄球菌、链球菌、沙门氏菌、棒状杆菌、大肠杆菌、酵母菌6种致病菌,其中,酵母菌最多,占32.81%,葡萄球菌和链球菌之和占40.63%. 相似文献
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