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排序方式: 共有231条查询结果,搜索用时 31 毫秒
61.
This work focused on inexpensive methods of evaluation fowl sperm morphology, based on eosin–nigrosin smears, which can determine disorders in spermatogenesis and can be recommended for evaluating the fertilising potency and selecting males in flocks reproduced by artificial insemination. Four fowl breeds (Black Minorca, Italian Partridge, Forwerk and Greenleg Partridge) were used to determine the efficacy of sperm morphology evaluation using four eosin–nigrosin staining methods (according to Blom, Bakst and Cecil, Morisson, Ja?kowski) and three examiners of different experience (high, medium, novice). There were significant (P ? 0.01) differences in sperm morphology between Blom’s staining method and those of Bakst and Cecil, Morisson or Ja?kowski, irrespective of fowl breed and examiners experience. Blom stain caused sperm head swelling and showed a drastic reduction in the proportion of live spermatozoa with normal morphology. The staining method had a greater influence on sperm morphology evaluation than the experience of the examiners. 相似文献
62.
鲟鱼类繁殖生物学研究进展 总被引:1,自引:0,他引:1
综述了鲟鱼类配子生物学的最新资料。间黄卵动物极具多个卵孔,膜分4层,最外层的胶质层含糖蛋白,其水合作用需Ca^2+、Mg^2+离子和类胰蛋白酶。鞭毛精子具顶体。顶体反应形成受精丝。 相似文献
63.
Quantifying spermatozoa concentration in milt samples is very important for aquaculture purposes, particularly when equal
numbers of gametes are needed for experimental purposes, and different methods can be used. Haemocytometer and Coulter counting
are the most precise methods to count spermatozoa, but they are very difficult to use when large numbers of samples are involved.
A standard curve of spectrophotometric absorbance (A) against sperm concentration ([S]) was used herein instead, and an equation for estimating spermatozoa concentration for
the mussel Mytilus edulis L. was obtained. The best wavelength to measure mussel spermatozoa was 320 nm, with a precision two or three times higher
than at other wavelengths. The equation for spermatozoa concentration was A = 8.592 × 10−5 [S] + 0.0190 (r
2 = 0.9979). Recommendations for choosing the best wavelength are discussed. 相似文献
64.
The aim of this study was to determine the spermatological characteristics in male L. abu during the spawning season. Semen was collected weekly by abdominal massage from 26 males in March. In collected semen, volume,
motility, duration of motility, concentration and pH were determined. In the L. abu sperm, volume (μl), motility (%), duration of motility (s), concentration (×109/ml), and pH values were found 45.76 ± 3.55, 54.25 ± 2.93, 330.15 ± 37.92, 4.27 ± 0.40 and 7.87 ± 0.05, respectively. A correlation
was found between semen volume and semen pH. Semen volume and the duration of sperm motility were higher in the 2nd and 3rd
sampling dates than in the 1st and 4th sampling dates (P < 0.05; P < 0.01, respectively). Neither sperm motility nor sperm concentration was affected by sampling dates. Major changes in semen
pH were observed in the 4th sampling date (P < 0.001). The Pearson correlation test presented significant relationships with the duration of motility, semen volume, and
motility. Semen pH values were significantly correlated with the sperm concentration and semen volume. Sperm concentration
was inversely correlated with semen volume. Sperm motility and duration significantly correlated with total weight. Total
length significantly correlated with the duration of motility and total weight. In conclusion, these characteristics represent
a valuable baseline dataset for establishing a semen quality standard and provide background information that may be useful
for assisted breeding programs in this species. 相似文献
65.
栉江瑶(Atrina pectinata)为我国重要的海洋经济双壳贝类,近年来,其养殖生产活动备受养殖企业关注,为发展和优化其人工繁殖技术,本研究探究了人工海水中铵离子浓度和pH的变化对栉江瑶新鲜精子游泳运动的激活作用,定量描述了高度活化状态下精子曲线运动速率(VCL)、直线运动速率(VSL)、平均路径运动速率(VAP)和鞭毛摆动频率(BCF)的运动学特征,并对精子ATP含量、ATP酶与超氧化物歧化酶(SOD)活性进行了记录。结果显示,简单提高海水pH可略微提高栉江瑶精子运动率,但无法使精子进入高度活化状态;含有铵离子的碱化海水可有效激发精子游泳运动,3 mmol/L氨海水激活效果最佳。经3 mmol/L氨海水激活后,精子活力等级(MI)在21 min内一直保持在≥4的状态,在激活的前3 min内精子运动率都在80%以上,VCL>56 μm/s,VSL>17 μm/s,VAP>30 μm/s,BCF>6 Hz。精子ATP含量在激活5 min后降低至初始含量的30.29% [(128.80± 66.92) μmol/g prot],随后,无显著变化(P>0.05)。精子Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶活性在运动过程中较为稳定,其中,Na+-K+-ATP酶活性较低[(0.62±0.03) U/mg prot],Ca2+-Mg2+-ATP酶活性较高[(6.08± 0.04) U/mg prot]。精子SOD活性在15 min内逐步降低至[(1.23±0.73) U/mg prot],随后维持稳定。本研究可为栉江瑶精子激活机制深入研究提供基础,助力发展栉江瑶人工繁育技术。 相似文献
66.
慢性氟中毒鸡精子质量测定研究 总被引:1,自引:0,他引:1
为探明慢性氟中毒对鸡精子质量的影响,本研究采用饮水染氟方法,人工复制公鸡慢性氟中毒模型,在染氟第三十、五十和七十天分别进行人工采精,测定精子密度、精子活力和精子畸形率。结果表明,慢性氟中毒可导致鸡精子密度和精子活力降低明显,精子畸形率明显升高。对照组精子密度、精子活力和精子畸形率在不同试验时间没有明显差异。而试验组精子密度第五十天和第七十天明显低于第三十天,但第五十天与第七十天无统计学差异;精子活力第七十天也明显低于第三十天,但第三十天与第五十天、第五十天与第七十天之间无统计学差异;试验组精子畸形率不同测定时间都无统计学差异。说明鸡慢性氟中毒呈现一种特定的时间-效应关系,而且精子畸形率可以相对独立的表现鸡对氟的慢性毒性。 相似文献
67.
68.
Samy M ELEAWA Mahmoud A ALKHATEEB Fahaid H ALHASHEM Ismaeel BIN-JALIAH Hussein F SAKR Hesham M ELREFAEY Abbas O ELKARIB Riyad M ALESSA Mohammad A HAIDARA Abdullah S. SHATOOR Mohammad A KHALIL 《The Journal of reproduction and development》2014,60(2):115-127
This study was performed to investigate the protective and therapeutic effects of
resveratrol (RES) against CdCl2-induced toxicity in rat testes. Seven
experimental groups of adult male rats were formulated as follows: A) controls+NS, B)
control+vehicle (saline solution of hydroxypropyl cyclodextrin), C) RES treated, D)
CdCl2+NS, E) CdCl2+vehicle, F) RES followed by CdCl2
and M) CdCl2 followed by RES. At the end of the protocol, serum levels of FSH,
LH and testosterone were measured in all groups, and testicular levels of TBARS and
superoxide dismutase (SOD) activity were measured. Epididymal semen analysis was
performed, and testicular expression of Bcl-2, p53 and Bax was assessed by RT-PCR. Also,
histopathological changes of the testes were examined microscopically. Administration of
RES before or after cadmium chloride in rats improved semen parameters including count,
motility, daily sperm production and morphology, increased serum concentrations of
gonadotropins and testosterone, decreased testicular lipid peroxidation and increased SOD
activity. RES not only attenuated cadmium chloride-induced testicular histopathology but
was also able to protect against the onset of cadmium chloride testicular toxicity.
Cadmium chloride downregulated the anti-apoptotic gene Bcl2 and upregulated the expression
of pro-apoptotic genes p53 and Bax. Resveratrol protected against and partially reversed
cadmium chloride testicular toxicity via upregulation of Bcl2 and downregulation of p53
and Bax gene expression. The antioxidant activity of RES protects against cadmium chloride
testicular toxicity and partially reverses its effect via upregulation of BCl2 and
downregulation of p53 and Bax expression. 相似文献
69.
Klaus-Peter BRüSSOW Istvan EGERSZEGI Jozsef RáTKY 《The Journal of reproduction and development》2014,60(5):395-398
The uterotubal junction (UTJ) and caudal isthmus are recognized as a functional pre-ovulatory sperm reservoir (SR).
Spermatozoa are released from the SR in a complex and concerted action. However, whether this functionality is restricted
only to the ovulatory period is still open to debate. Our study was aimed to analyze the presence of spermatozoa within the
UTJ (SR), isthmus (ISTH) and ampulla (AMP) after laparoscopic intrauterine insemination (LIUI) either in the peri- (PERI) or
post-ovulatory (POST) period or at mid cycle (MID). Each uterine horn of estrus synchronized gilts (n=12) was inseminated
with 20 ml sperm (29.5×106 cells/ml). Oviducts were recovered 7 h after LIUI and separated into the UTJ, ISTH and
AMP, and sections were flushed with 10 ml PBS+EDTA solution. After centrifugation, the sperm pellet was evaluated by Čeřovský
staining. The median sperm numbers in the PERI, POST and MID groups were 578, 171 and 789 in the UTJ; 545, 233 and 713 in the
ISTH; and 496, 280 and 926 in the AMP, respectively, and there were differences between the POST and MID groups (P<0.05)
but not between the oviductal sections of each group (P>0.05). Compared with the MID group, the percent of intact sperm
cells was higher (P<0.01) in the PERI and POST groups (32.8 vs. 66.4 and 76.8%). Also,
the percentages of aberrations in the acrosome and tail were higher (P<0.05) in the MID group. Based on this, it can be
assumed that the sperm reservoir is active during different phases of the estrus cycle. However, the mid-cycle oviduct
environment considerably impairs sperm cell quality. 相似文献
70.
介绍了一种用常规的自然热电偶和标准热电偶方法实现高速加工过程中切削温度的直接接触式测量的计算机辅助测温系统。它采用自然热电偶测量刀一工界面温度,采用夹丝热电偶测温技术对工件表面和体内温度分布进行直接接触式测量。该方法可以应用于刀具旋转的切削加工中(例如立钻、立铣)测量切削温度,并已在高速立铣淬硬钢研究中得到应用。 相似文献