单环刺螠受精过程的细胞学观察   总被引：1，自引：0，他引：1  

董英萍  张志峰  邵明瑜 《中国水产科学》2011,18(4):760-765

利用组织学和荧光显微镜对单环刺螠(Urechis unicinctus)受精过程中精子入卵以及核相变化进行了观察.结果表明:单环刺螠成熟卵呈卵圆形,核相处于生发泡尚未破裂的第1次成熟分裂前期.在(21±1)℃时,精卵混合后约5 min,精子由卵偏向植物极一侧入卵,受精膜开举起,继而精核发生第1次膨胀.直至受精后约25 min,受精膜完全举起;受精后10～50 min,卵核相继完成二次成熟分裂,分别形成第一极体和第二极体;受精后50～70 min,精核卵核分别膨胀,形成雄原核和雌原核,进而相向迁移,最后在卵的中央联合形成合子核.受精后70～90 min,受精卵完成第1次卵裂,形成2个大小相等的卵裂球.单环刺螠受精全过程历时约70 min,略长于多数海洋无脊椎动物的受精持续时间.本研究旨在为今后单环刺螠人工育苗和新品种的培育提供基础资料.  相似文献   

Cytological studies on induced meiogynogenesis in Japanese flounder Paralichthys olivaceus (Temminck et Schlegel)     

Jilun Hou  Zhaohui Sun  Fei Si  & Haijin Liu 《Aquaculture Research》2009,40(6):681-686

The cytological process of induced gynogenetic development and subsequent chromosome duplication by a cold shock treatment was observed in Japanese flounder Paralichthys olivaceus (Temminck et Schlegel). Mature eggs were at the metaphase of the second meiosis when inseminated with ultraviolet (UV)-irradiated sperm of red sea bream Pagrus major . After the beginning of cold shock treatment, the previously visible spindle became invisible, probably due to the side effect caused by cold shock treatment. The chromosomes at the centre of the metaphase plate were condensed. This condition continued during the duration of the cold shock treatment and several minutes after it. The release of the second polar body was blocked and it developed into a female-like pronucleus. Then, it fused with the female pronucleus to generate a diploid zygotic nucleus, and the egg exhibited the first mitosis. Consequently, the haploid female chromosome set of the egg was doubled by the inhibition of the second polar body release. There was a significant delay in developmental time in the gynogenetic eggs when compared with that in the normal eggs. From the time of insemination to early cleavage, the UV-irradiated heterospecific sperm nucleus remained condensed.  相似文献   

Submitting High-Quality Clinical Pathology Samples for Best Results     

《Veterinary Clinics of North America: Food Animal Practice》2023,39(1):33-47

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不同类型雄性不育苎麻细胞学机理研究          下载免费PDF全文

薛丽君  邢虎成 《湖南农业大学学报(自然科学版)》2014,40(1):13-18

为探明苎麻雄性不育材料和可育材料在花芽分化和花药发育上的差异，选取不可育材料雄花萎缩型园青5号、花被不开裂型弯子苎麻、花粉不育型黄小叶和可育材料中苎1号(对照)，采用常规石蜡切片技术对其进行雄花花芽发育形态比较。结果表明：3种雄性不育苎麻花芽发育较可育苎麻中苎1号快，在花芽发育到0.3~0.5 cm时，已完成了雌、雄蕊的分化。参照可育苎麻材料的花芽分化和花药发育，推测3种雄性不育材料不育的原因分别为园青5号花芽在分化出花药和花丝后，花药不会继续分化形成花粉囊，而是变形萎缩甚至消失形成空腔；弯子苎麻在花粉分化阶段花被木质化严重；黄小叶花粉囊不破裂，花粉粒颜色逐渐变深，花丝发育异常。  相似文献   

Pot-bellied Vietnamese pig with visceral mast cell tumors and mastocytemia     

Abby M. Willey  Brittany S. Baughman  Jennifer M. Beam  Nataly Mamaliger  Gretchen P. Grissett  Amelia R. Woolums  Marjorie J. Williams  Matthew L. Williams 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2023,52(1):108-111

An approximately 12-year-old female Vietnamese Pot-Bellied Pig was presented to the Mississippi State College of Veterinary Medicine Food Animal Service for anorexia of 2 days duration. On physical examination, the patient appeared depressed and lethargic with significantly pale mucus membranes, open mouth breathing, and nostril flaring. On abdominal palpation, the abdomen was tense and uncomfortable. A complete blood count (CBC) and chemistry profile were performed. The CBC revealed significant anemia and mild leukocytosis characterized by mild neutrophilia with a left shift. Mast cells were rarely observed. Hematocrit = 8.1% (RI 22-50), RBC = 1.25 × 10⁶/μL (RI 3.6-7.8), WBC = 19.85 × 10³/μL (RI 5.2-17.9), Neutrophils = 15.08 × 10³/μL (RI 0-11.4), and Bands = 0.993 × 10³/μL (RI 0-0.019). The chemistry profile was unremarkable with a mildly elevated BUN and slightly decreased total protein and albumin (BUN = 39 mg/dL [RI 4.2-15.1], total protein = 6.2 g/dL [RI 6.6-8.9], and albumin = 2.5 g/dL [RI 3.6-5.0]). An abdominal ultrasound revealed numerous hypoechoic nodules diffusely scattered throughout the hepatic parenchyma. An FNA of one of the hepatic nodules was performed. A mild suppurative component and numerous variably granulated mast cells were observed. A presumptive cytologic diagnosis of mast cell tumor was made. Histopathology was performed, confirming the cytologic interpretation.  相似文献