Toxico-pathological effects of cypermethrin upon male reproductive system in rabbits

The objective of this work was to identify the reproductive toxico-pathological effects of cypermethrin (CY) in mature male rabbits. Apparently healthy adult age- and weight-matched rabbits (n = 40) were procured from the local market, kept under similar management conditions and divided into four equal groups. Different doses of CY (50, 100 and 150 mg kg⁻¹ body mass) mixed in mustard oil were injected intraperitonealy at weekly intervals in male rabbits (groups B-D) prior to mating. Group A served as control and each animal in this group received equivalent volume of mustard oil. Treatment was continued for 71 days. Decreased testicular and epididymal sperm counts were recorded mostly in dose and time dependent manner in CY-treated rabbits. The serum testosterone concentrations in CY-treated rabbits were significantly lower than those of control group. Degeneration, arrested spermatogenesis and connective tissue (CT) proliferation in testes, while sperm-less seminal plasma and tailless spermatozoa in epididymis of CY-treated rabbits were observed. It was inferred that CY-induced defects in sperms and pathological alterations in testes and epididymis.     

海风藤酮对PAF影响长白猪精子活率及运动能力的拮抗作用

人工采集长白猪精液，经过处理后制成精子悬浮液并分为７组，其中一组加入１０ｍｇ／ｍｌ的血小板活化因子（Ｐｌａｔｅｌｅｔ－Ａｃｔｉｖａｔｉｎｇ Ｆａｃｔｏｒ，ＰＡＦ），以空白为对照。海风藤酮（Ｋａｄｓｕｒｅｎｏｎｅ，ＫＡＤ）设５个浓度组，以ＰＡＦ组为对照，在３７℃恒温水浴中温育５、１５、２５、３５、４５和６０ｍｉｎ，显微镜下检测精子活率，用浊度分析法检测快速运动相精子的平均速度（Ａｖｅｒａｇｅ ｖｅｌ     

精子载体转基因技术的最新研究进展

用动物精子作为外源DNA载体已成为转基因的主要方法之一,并在多种动物上获得成功.最近,人们对外源DNA与精子结合的分子机理进行深入研究发现外源DNA可与精子膜上30～35 kDa蛋白质特异结合,结合强度受精子膜上MHCII因子的调节.精清中的IF-1因子能抑制精子结合外源DNA,从而维持物种的遗传稳定性.精子结合外源DNA的量是恒定的,部分DNA能进入精子核内,CD4蛋白具有转运外源DNA进入精子核内的功能.进入核内的外源DNA牢固结合在精子核骨架上,然后整合到染色体的特异位点.但是,精子与外源DNA结合后能激活精子内的核酸酶,进而使外源DNA分子降解,可能是导致这种转基因方法稳定性差的主要原因.     

Sperm storage and low incidence of multiple paternity in the European pond turtle, Emys orbicularis: A secure but costly strategy?

The freshwater pond turtle, Emys orbicularis, has recently suffered from population declines throughout its range, mainly due to habitat destruction. The mating strategies of this species were studied using genetic data from successive clutches within and between years. To test for the occurrence and frequency of multiple paternity and sperm storage, genetic paternity at six microsatellite markers was assessed in 114 embryos and hatchlings from single and subsequent clutches of 11 females (including clutches from the same or consecutive years). Multiple paternity was rare and only found in two out of 20 clutches from 11 females. All annual successive clutches and 58% of the clutches in the next year, were fertilized with sperm from the same male. The use of stored sperm is thus a frequent strategy in E. orbicularis. However, hatching rate, hatchling mass, and hatchling length decreased in clutches fertilized by stored sperm, suggesting sperm depletion or deterioration through time. The occurrence of stored sperm despite an associated reduced reproductive output indicated that mating and/or the fertilization process is costly to females. The low incidence of multiple paternity may simply be the residual consequence of the capacity to store viable sperm. These results provide important and innovative insights for the conservation of E. orbicularis. In threatened populations, management strategies may aim to enhance effective copulations in order to increase the reproductive output of females.     

Sperm winding in Collembola

The winding process leading to the formation of rolled-up spermatozoa in Collembola is described. It is a phenomenon common to all collembolan species examined so far and it starts with the organization of a cytoplasmic flattened evagination beneath the head of the elongated spermatid, which gives rise to an extracellular cavity. Within this cavity secretory material produced by the epithelial cells of testes is progressively stored. The spermatozoon, whose cytoplasm is reduced to a thin layer, enrolls around this material. The final appearance is that of a spheroidal or lenticular structure containing dense material in the central extracellular cavity; this cavity is surrounded by the flattened sperm in whose cytoplasm the sperm components forms several spires. The material into the extracellular cavity becomes progressively denser and has a different appearance in the species examined.     

海藻糖和甘油相互协同提高绒山羊精液冷冻保存品质

本实验旨在研究不同浓度的海藻糖和甘油相互协同对绒山羊精液冷冻保存的影响。将0 mmol/L (T0)、50mmol/L(T50)的海藻糖和0%(G0)、1%(G1)、2%(G2)、3%(G3)的甘油分别组合为T0G0、T0G1、T0G2、T0G3、T50G0、T50G1、T50G2和T50G3。以Tris-柠檬酸-葡萄糖(TCG)为基础稀释液,分析不同组合对绒山羊精液冷冻保存的影响。检测解冻后精子活力、运动参数、DNA完整率、顶体、质膜完整率、抗氧化水平。结果表明:海藻糖和甘油联合添加时精子冷冻保存效果显著高于单独添加海藻糖或甘油组,其中T50G1组作用最显著。在基础稀释液中添加50 mmol/L(T50)的海藻糖时,精子冷冻解冻后的活力、质膜完整率随着甘油浓度的升高而降低,而在基础稀释液中不添加海藻糖时,精子冷冻解冻后的活力、质膜完整率随着甘油浓度的升高而升高。综上表明,海藻糖和甘油通过协同作用提高精子冷冻保存效果,两者发挥作用的最适浓度为50 mmol/L海藻糖和1%甘油,并且海藻糖和甘油协同作用对精子活力以及质膜完整性具有浓度依赖性。     

异科精子在蚕卵中的命运

取受精囊里的精液(含异科精子)应用离体人工授精经卵孔入卵;即,蓖麻蚕(?)→多化性家蚕(?)及家蚕(?)→蓖麻蚕(?),并作细胞学观察,表明停滞在第一成熟分裂的卵细胞被远缘精子活化,过后,入卵的精子演变则受卵细胞质所控制.但,尚未见雌雄原核的融合,似系假受精作用.无论怎样,精子中心粒一旦与卵细胞器配合而聚成具功能的中心体,可促使子核岛出现调整和分裂.囊胚的形成,是造胚子的临界期.我们曾分别从对照组(家蚕(?)→家蚕(?),30/160)及科间授精组(蓖麻蚕(?)→家蚕(?),2/754)得到子代.讨论了精-卵相互作用等.     

甘蔗黄螟精子的超微结构及辐射对其影响

本研究观察了正常黄螟睾丸中精子细胞的超微结构。并研究在蛹后期照射~(60)COγ—射线3.0万伦琴处理舌对当代雄虫,和照射1.5万伦琴处理后羽化的雄虫,与正常雌虫配对所产的子代雄虫(F_1)睾丸的精子细胞超微结构的影响。 经辐射处理后的当代雄成虫和(F_1)代雄成虫,其睾丸中的精子绝大多数具有正常的超微结构。从结果表明往后期蛹,用本试验的两个处理剂量,对当代及F_1代雄成虫精子的超微结构影响很小。在应用上,既能达到理想不育效果,又不影响其交尾受精竞争能力。本研究结果为应用辐射不育技术防治黄螟提供理论依据。     

雄性生殖细胞介导外源DNA转移的新方法

介绍并评价在传统精子载体法的基础上的改进与发展,即辅以生精细胞显微授精的基因转移;输精管注射法体内转染成熟精子和曲细精管注射法转染生精干细胞.这些方法的应用将为哺乳动物基因转移提供更为方便和高效的技术手段.     

GnRH和LHR基因多态性和牛精液品质性状的相关分析

本试验采用PCR—RFLP方法分析了GnRH基因外显子2和LHR基因内含子9在144头中国荷斯坦牛和79头河南地方肉牛品种中的多态性,利用最小二乘法分析多态位点不同基因型与精液品质性状的关系。研究结果表明,2～3岁荷斯坦牛的鲜精活力显著高于4岁以上的牛,而畸形率显著低于7岁以上的牛。对2～4岁荷斯坦牛不同精液品质性状的简单相关分析表明,畸形率与顶体完整率和冻精活力呈显著的负相关（相关系数r分别为-0．736和-0．500）。不同基因型与精液品质性状的关联分析结果表明,144头中国荷斯坦牛所研究位点不同基因型对精液品质性状没有显著影响。而河南地方肉牛GnRH基因外显子2的A883G位点GG基因型的精子密度显著低于AA和AG基因型．LHR基因G51656T位点的TT基因型精子密度显著高于GT基因型,未检测到GG基因型。并且发现随着年龄的增长,种公牛的精液品质逐渐变差。GnRH和LHR基因可作为影u向肉牛精液品质性状的候选基因。