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[目的]探讨适合于牛卵母细胞体外受精以及受精卵体外培养的最佳培养体系。[方法]通过对成熟的牛卵母细胞分别采用传统培养体系(对照组)和过渡培养体系(试验组)进行体外受精和受精卵体外培养,研究了不同组合的培养体系对受精率和卵裂率的影响。[结果]以受精液为TALP液,受精卵培养液为60%TALP液+40%M-199液+5%FCS的过渡培养体系能够提高牛体外成熟卵母细胞的受精率和卵裂率,分别为77.8%和55.6%。[结论]受精液为TALP液,受精卵培养液为60%TALP液+40%M-199液+5%FCS的过渡培养体系为牛卵母细胞体外受精以及受精卵体外培养的最佳培养体系。 相似文献
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C.S. Keator E.E. Custer T.A. Hoagland D.T. Schreiber K. Mah A.M. Lawson O.D. Slayden J.A. McCracken 《Domestic animal endocrinology》2010
Neuropeptide Y (NPY) is a neurohormone that is typically associated with food intake, but it has also been reported to affect the production of progesterone from luteal tissue in vitro. However, NPY has not been previously immunolocalized in the ovine ovary or in the corpus luteum (CL) of any species, and the effects of this neurohormone on luteal function in vivo are not known. Thus, we performed fluorescent immunohistochemistry (IHC) to localize NPY in the ovine ovary and used avidin-biotin immunocytochemistry (ICC) to further define the intracellular localization within follicles and the CL. We then infused NPY directly into the arterial supply of the autotransplanted ovaries of sheep to determine the in vivo effect of exogenous NPY on ovarian blood flow and on the luteal secretion rate of progesterone and oxytocin. Immunohistochemistry revealed that the NPY antigen was localized to cells within the follicles and CL, in the nerve fibers of the ovarian stroma, and in the vessels of the ovarian hilus. In the follicle, the NPY antigen was localized to nerves and vessels within the theca interna layer, and strong staining was observed in the granulosal cells of antral follicles. In the CL, NPY was localized in large luteal cells and in the vascular pericytes and/or endothelial cells of blood vessels, found dispersed throughout the gland and within the luteal capsule. In vivo incremental infusions of NPY at 1, 10, 100, and 1,000 ng/min, each for a 30-min period, into the arterial supply of the transplanted ovary of sheep bearing a CL 11 d of age increased (P ≤ 0.05) ovarian blood flow. The intra-arterial infusions of NPY also increased (P ≤ 0.05) in a dose-dependent manner the secretion rate of oxytocin, which was positively correlated (P ≤ 0.05) with the observed increase in ovarian blood flow. The infusions of NPY had a minimal effect on the secretion rate of progesterone, and similar intra-arterial infusions of NPY into sheep with ovarian transplants bearing a CL over 30 d of age had no significant effect on ovarian blood flow or on the secretion rate of progesterone. These results suggest that NPY acts on the luteal vascular system and the large luteal cells to rapidly stimulate blood flow and the secretion of oxytocin, respectively, which collectively implies a putative role for NPY during the process of luteolysis when increasing amounts of oxytocin are secreted from the ovine CL in response to uterine pulses of prostaglandin F2α. 相似文献
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Fruit weight is strongly correlated to ovary weight in olive as big-fruited cultivars have larger ovaries and flowers at bloom. We tested the hypothesis that larger ovaries imply stronger sinks and therefore reduce fruit set, expressed as number of fruits. Flower/fruit load per centimeter of shoot was assessed every month from flowering to harvest, on sample shoots of many different olive cultivars differing in fruit size. Data were taken for two years: 2007 and 2008. Additionally, in 2008, a fruit thinning experiment was carried out by leaving a single fruit per shoot, to assess the maximum potential fruit weight achievable by each cultivar. Results indicated that fruit size was mostly genetically determined as thinned fruits of small-fruited cultivars, although bigger than control fruits, never got as big as fruits from large-fruited cultivars, confirming that large ovaries are a prerequisite for large fruits. Among all cultivars, the number of flowers per inflorescence, the number of inflorescences, and the number of flowers per centimeter of shoot were not correlated to average flower weight while total flower mass per centimeter of shoot was positively correlated to average flower weight (i.e. large flowered/fruited cultivars had greater total flower mass). However, one month after bloom and thereafter, all parameters were negatively and exponentially correlated with fruit average weight across cultivars, except fruit mass per centimeter of shoot which was generally not correlated to fruit average weight, except in one year, at harvest, when fruit mass per centimeter of shoot was positively correlated to fruit average weight. These results suggest that fruit set is a consequence of, and inversely proportional to flower/fruit size in olive. 相似文献
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本研究通过组织学观察,描述了黄海高眼鲽(Cleisthenes herzensteini)卵母细胞发育特征及其退化过程。高眼鲽卵母细胞发育分为5个时相:第1时相为卵原细胞,细胞体积小,细胞质少,细胞核明显;第2时相卵母细胞细胞核附近出现卵黄核;第3时相由胞质外缘向内层逐渐产生液泡并生成卵黄颗粒,出现双层滤泡膜;第4时相卵母细胞内充满卵黄,细胞核向动物极移动,放射膜增厚;第5时相细胞核溶解,卵母细胞从滤泡膜中释放出来并发生水合作用;产卵期过后,卵巢发生退化,卵黄颗粒逐渐被吞噬,放射膜溶解断裂。通过比较卵巢中各时相卵母细胞组成比例,表明卵母细胞发育具有非同步性。Ⅳ、Ⅴ、Ⅵ-Ⅳ'期卵巢内卵径(长径)呈单峰分布,优势粒径组分别为0.45~0.55 mm、0.60~0.65 mm和0.40~0.50 mm;Ⅴ'期卵巢,卵径分布呈双峰型,峰值分别为0.50~0.55 mm和0.90~0.95 mm,水合卵母细胞与卵径较小的小生长期卵母细胞比例增大,呈现出明显的双峰分批产卵型特征。 相似文献
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以甘蓝型波里马胞质雄性不育系油菜为母本,与青花菜杂交,在授粉后不同天数,利用不同的培养基对其种间杂种的子房进行培养,利用Nitsch(1956)和改良White(1963)培养基所培养获得的种子数和幼苗数均多于Ms和1/2Ms培养基。从幼苗数目来看,培养的时间越早,其幼苗数目越多。 相似文献
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