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排序方式: 共有231条查询结果,搜索用时 15 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.
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.
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
66.
The objective of this study is to evaluate the effect of body size, temperature and annual cycle on sperm production in Cherax quadricarinatus. Sperm count and sperm mortality were estimated, the reproductive system was weighted, and macro and microscopical analysis of the testes and vasa deferentia were conducted. Sperm count and weight of the reproductive system are strongly related to male size, in contrast to sperm mortality. The spermatophore structure presented macro and microscopical differences between sizes. Males higher in size have more adherent spermatophores. This species has a reproductive cycle related to sperm production. Sperm count and weight of the vasa deferentia rise in summer, while the weight of the testes increases in winter. During the spring, the sperm cord presents a higher density than in other seasons. The temperature seems to affect sperm production being 27 and 29 °C the best assayed conditions. The present results are relevant information to obtain the best sperm viability selecting male size, season of sampling and the best temperature for the reproductive stock and future assays of spermatophore cryopreservation for this species aquaculture. 相似文献
67.
石鲽、牙鲆精子冷冻保存研究及其在人工杂交中的应用 总被引:13,自引:2,他引:13
对石鲽(Kareius bicoloratus )和牙鲆(Paralichthys olivaceus)精子冷冻保存技术进行了研究,筛选到一个优良的稀释液MPRS,用MPRS冷冻保存石鲽、牙鲆精子,冻后成活率在70%以上。在石鲽冻精和牙鲆卵的杂交实验中,杂交组受精率是 28 4%±4 55(n=3),孵化率是 42 7%±7 35(n=3),胚胎发育正常;5 000尾杂交鱼苗有102尾成功度过变态期。在牙鲆冻精和大菱鲆卵的杂交实验中,杂交组的受精率只有2 7%,部分受精卵虽能孵化出膜,但仔鱼全为畸形。这两个杂交实验,特别是石鲽冻精和牙鲆卵的杂交实验,证实了冷冻保存的精子完全可以应用在杂交育种工作中。 相似文献
68.
Subuntith Nimrat Sopon Siriboonlamom Yuyan Xu 《Aquaculture (Amsterdam, Netherlands)》2006,261(3):944-951
Chilled storage of spermatophores from white shrimp (Litopenaeus vannamei) is needed to generate a consistent and reliable supply of spermatozoa for domestication purposes. The objective of this study was to develop a protocol for the chilled storage of white shrimp spermatophores and to evaluate bacterial propagation during such storage. In the first experiment, spermatophores were immersed in four extenders, mineral oil, Ringer's solution, phosphate buffer and 0.85% NaCl, and stored at low temperature (2-4 °C) for 35 days. Characteristics of preserved spermatophores changed the least and viable sperm was highest when spermatophores were stored in mineral oil. Spermatophores preserved with mineral oil appeared morphologically normal. Bacillus circulans, Staphylococcus hominis and S. lugdunensis, S. sciuri, S. xylosus and Micrococcus spp. were identified as the predominant bacteria during chilled storage, and total bacterial counts gradually increased during the experiment. A second experiment investigated the effect of antibiotic on chilled storage. Spermatophores were preserved in only mineral oil or mineral oil with 0.1% penicillin-streptomycin. These were evaluated for changes in external morphology of spermatophores, sperm viability and total bacteria count every week during a 35-day experimental period. Percentages of viable sperm (69.5 ± 3.9%) were significantly higher (P < 0.05) among spermatophores preserved in mineral oil with 0.1% antibiotic compared with those preserved only in mineral oil (57.7 ± 3.4%) over 35 days. The number of total bacteria in the treatment with mineral oil ranged between 28.3 ± 4.8 and 2416.7 ± 299.4 CFU/g, but in mineral oil containing antibiotic bacteria were undetectable. This study suggests that chilled storage of spermatophores is a feasible approach for the management and spawning of white shrimp broodstock. 相似文献
69.
Kevin Richard Butt 《Soil biology & biochemistry》2011,43(10):2169-2175
Birch leaves and horse manure were used to determine the effects of food quality on growth and reproduction of laboratory-reared Lumbricus terrestris. Animals grew to maturity within 6 months but attained a significantly (p < 0.001) larger adult size with manure (6.17 g) versus leaves (4.20 g). Cocoon production by recently-mated adults maintained in isolation, fed with birch leaves or horse manure, resulted in 4.53 and 3.84 cocoons ind.−1 month−1 respectively, with an initial hatchability of 86%, falling to zero after 18 months. Re-mating of these known individuals permitted long term monitoring of reproductive output (to 30 months). For the whole experimental period, overall hatchability of the 2010 cocoons produced was 44.4%. Median incubation time of those cocoons that hatched within accepted norms (less than 5 months at 15 °C) was 103 days and was not influenced by adult food type. A proportion (35.5%) of cocoons took in excess of 12 months to hatch. Adult mortality was minimal (25%) during the long term experiment but abnormal cocoon production was recorded after 2 years. Overall results demonstrate that food quality can have a significant influence on somatic and reproductive production of L. terrestris and these data may aid construction of production models for this earthworm in ecosystems with contrasting food quality. 相似文献
70.
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