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71.
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
72.
73.
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
74.
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
75.
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
76.
[目的]探索适用于犬性别控制的流式细胞仪分离精子的方法。[方法]采集昆明犬和德国牧羊犬的精液,采用不同浓度(6、8、10、12μl/ml)的Hoechst 33342对精液进行染色,探讨不同浓度的荧光染料Hoechst 33342及公犬个体对精子分离效果的影响。[结果]当Hoechst 33342浓度分别为6、8、10μl/ml时,X和Y精子的DNA差异不能被分辨成双峰,只有当Hoechst 33342为12μl/ml时,X/Y双峰能有效并稳定地分离。不同公犬的鲜精死精率与X/Y精子分离速度呈明显负相关性,而分离准确率则与鲜精死精率无明显相关性。[结论]当Hoechst 33342浓度为12μl/ml时,流式细胞仪能将警犬X、Y精子成功分离。选择适宜的种公犬对提高精子的分离效率和分离精液的品质都有重要意义。 相似文献
77.
Large yellow croaker, Pseudosciaena crocea, exhibit sexually dimorphic growth, with females growing faster and reaching larger adult sizes than males. Thus, development
of techniques for preferentially producing females is necessary to optimize production of these species. We have established
a protocol to produce all-female croaker P. crocea through induction of meiotic gynogenesis with homologous sperm. The first set of experiments investigated the ultra-violet
(UV) irradiation on sperm motility and duration of sperm activity to determine the optimal UV dosage for genetic inactivation
of sperm, yet retaining adequate motility for activation of eggs. Milt from several males was diluted 1:100 with Ringer’s
solution and UV irradiated with doses ranging from 0–150 J cm−2. The results indicated that motility and duration of activity generally decreased with increased UV doses. At UV doses greater
than 105 J cm−2, after fertilization, motility was <10% and fertilization rates were significantly lower. Highest hatching rate was obtained
at 75 J cm−2. A second set of experiments was carried out to determine appropriate conditions of cold shock for retention of the 2nd polar
body in P. crocea eggs after fertilization with UV-inactivated sperm by altering the timing, temperature and duration of shock. At 20°C, shock
applied at 3 min after fertilization resulted in higher survival rate of larvae at 6 h after hatching. Results of different
combinations of three shock temperatures (2°C, 3°C or 4°C) and five shock durations (4 min, 8 min, 12 min, 16 min or 20 min)
at 3 min after fertilization demonstrated that shocks of 12 min gave highest production of diploid gynogens. Statistical analysis
revealed that maximum production of diploid gynogens (44.55 ± 2.99%) were obtained at 3°C. The results of this study indicate
that the use of UV-irradiated homologous sperm for activation of P. crocea eggs and cold shock for polar body retention is an effective method for producing gynogenetic offspring. 相似文献
78.
Han Kyu Lim Ned William Pankhurst Quinn Patrick Fitzgibbon 《Aquaculture (Amsterdam, Netherlands)》2004,240(1-4):505-516
Spermiated male greenback flounder (Rhombosolea tapirina) were implanted with gonadotropin releasing hormone analog (GnRHa) pellets at different dosages to examine their effects on milt characteristics and plasma levels of testosterone (T), 11-ketotestosterone (11KT) and 17,20β-dihydroxy-4-pregnen-3-one (17,20βP). Milt and blood samples were collected for up to 28 or 42 days post-implantation (p.i.) in two separate experiments using fish that were slightly or moderately spermiated, respectively. In both experiments, fish treated with GnRHa pellets showed a consistent and significant increase in milt volume relative to controls, and the increase of milt volume was more rapid than the increase in numbers of spermatozoa. Spermatocrit (Sct) was significantly lower in GnRHa-treated fish than in controls. Plasma levels of T and 11KT were elevated at 7 and 14 days p.i. in slightly spermiated fish treated with GnRHa and elevated plasma T and 11KT levels were accompanied by increased milt volume early in the spermiation period. In contrast, there was no significant difference in plasma T levels between GnRHa-treated and control fish in fish that were moderately spermiated at the time of implant. Treatment with GnRHa tended to result in lower plasma levels of 11KT and higher levels of 17,20βP relative to controls, and there was a positive relationship between the elevation of plasma 17,20βP and the increase in milt volume in response to implantation of GnRHa pellet. Slow release GnRHa administration had no effect on sperm activity or pH and osmolality of seminal plasma in either experiment. 相似文献
79.
Successful hybridization of sterlet (Acipenser ruthenus) × Siberian sturgeon (Acipenser baeri), sterlet × Russian sturgeon (Acipenser gueldenstaedti) and sterlet × European sturgeon (Acipenser sturio) was carried out for the first time using cryopreserved semen of sturgeon males and sterlet × sterlet crosses as controls. Sperm of all three species was diluted with a cryodiluent composed of 23.4 mM sucrose, 0.25 mM KCl, 30 mM Tris (pH 8.0) and 10% methanol. The samples were frozen in plastic straws in the vapor of liquid nitrogen at the height of 3 cm above the level of nitrogen for 3 min. Following thawing approximately 3000 sterlet eggs were fertilized with six straws of frozen-thawed sperm. The hatching rate with sterlet sperm was 30.6% while the hatching rate of A. ruthenus × A. baeri, A. ruthenus × A. gueldenstaedti and A. ruthenus × A. sturio hybrids was 50, 17.4 and 34%, respectively. Morphometric markers as well as random amplified polymorphic DNA (RAPD) assay was used to verify interspecific hybridization. 相似文献
80.