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51.
蜂胶的开发利用使得蜂胶生产远不能满足市场需求.通过引入高加索系列品种、本意、喀尔巴阡以及东北黑蜂,采用蜂王人工授精技术加以组配,进行筛选.培育出高产蜂胶的优良杂交组合,借以提高蜂胶产量,满足蜂胶市场需求,使蜂农增收,提升人们的健康水平. 相似文献
52.
Birth of puppies of predetermined sex after artificial insemination with a low number of sex‐sorted,frozen–thawed spermatozoa in field conditions 下载免费PDF全文
Shu‐Sheng Tang Ai‐Guo Mao Li‐Guang Li Lu‐Guang Cheng Chao Chen Fei‐Xiang Li Bin Wang Tao Xu Yue‐Jun Zhang Jing Li Jiu‐Sheng Wan 《Animal Science Journal》2017,88(8):1232-1238
The aim of this study was to evaluate fertility and sex ratios after artificial insemination in dogs under field conditions. Semen was cryopreserved as unsorted (control) or was separated into X‐ and Y‐chromosome‐bearing sperm using a cell sorter. Sixty female dogs were inseminated with frozen–thawed spermatozoa of 100 × 106 unsorted (a dose in practice) and 4 × 106 sorted (X and Y group, respectively). A total of 20 dogs became pregnant and 126 puppies were born from the three groups. The percentage of parturition was similar for the X (5/20; 25.0%) and Y (4/20; 20.0%) group (P > 0.05), but lower than controls (11/20; 55.0%) (P < 0.05). Ultimately 28 out of the 32 puppies produced from X group were female (87.5%) and 19/22 (86.4%) puppies of Y group were male. In contrast, sex ratio (51.4% to 48.6%) in the control was significantly different from the X, Y group (P < 0.05). However, male and female puppies in the control had similar birth weights and weaning weights to those from the X and Y groups. This preliminary information indicated that normal puppies of predicted sex can be produced with low numbers of sorted cryopreserved dog spermatozoa at a farm level, making sperm‐sexing technology potentially applicable for elite breeding units. 相似文献
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Canisso IF Carvalho GR Morel MD Ker PG Rodrigues AL Silva EC Coutinho Da Silva MA 《Equine veterinary journal》2011,43(2):179-183
Reasons for performing study: As mule production is often concentrated in remote areas of the world, a simplified semen cryopreservation protocol is required. Aim: To compare the seminal parameters of cryopreserved donkey semen in lactose‐EDTA and lactose‐yolk extenders and the fertility rates on horse mares. Methods: Trial 1: Sperm total and progressive motility, vigour (scale 0–5), morphology (major and minor defects) and plasma membrane integrity (HOST) were evaluated in 25 ejaculates from 5 donkey jacks immediately after collection (raw), after chilling to 5°C (chilled) and after freezing/thawing. The semen was mixed with skimmed‐milk extender, centrifuged, and then re‐suspended in lactose‐EDTA or lactose‐yolk extender. Semen was loaded into 0.5 ml straws and chilled to 5°C for 1 h, after which samples were either evaluated (chilled semen) or placed above liquid nitrogen for 20 min prior to immersion. Seminal parameters were evaluated by ANOVA and Tukey's test. Trial 2: Cryopreserved semen from 3 males was used to inseminate 53 mares at 60 oestrous cycles randomly assigned to lactose‐yolk (n = 30 cycles) or lactose‐EDTA (n = 30 cycles) extenders. Pregnancy diagnosis was performed 15 and 25 days post ovulation. The pregnancy rates were compared using Chi‐squared tests. Results: Trial 1: No significant differences were evident in any seminal parameters between extenders after either chilling or cryopreservation. Total and progressive motility were significantly (P<0.05) lower in cryopreserved semen than raw and chilled semen for both extenders. Trial 2: Pregnancy rates did not significantly differ between extenders (lactose‐EDTA extender 53.33 and 43.33%; lactose‐yolk 50.0 and 46.66% for Days 15 and 25 post ovulation, respectively). Conclusions: Cryopreservation of donkey semen using the simplified lactose‐yolk extender resulted in similar seminal parameters and fertility rates when compared to lactose‐EDTA extender. Potential relevance: Lactose‐yolk extender may be advocated as a simple, easy to prepare extender, for use in geographically isolated enterprises producing mules throughout the world. 相似文献
55.
Oxytocin (OXT) contained in boar semen is known to produce uterine contraction; therefore, we hypothesized that the co‐injection of OXT with sperm would improve artificial insemination (AI) using liquid or frozen‐thawed boar sperm. We initially examined whether OXT added to semen extender improved sperm transport to the oviduct. Although the addition of OXT did not affect the fresh or frozen‐thawed sperm motility or acrosomal integrity, it significantly increased the number of sperm in the oviduct at 6 h after AI injection with OXT, as compared with the control (P < 0.05). Moreover, some sperm were observed in the sperm reservoir of the isthmus in the OXT treatment group, whereas few sperm were observed in the control. When OXT was added to the semen extender immediately prior to AI, the conception rates were significantly higher in both fresh semen and frozen‐thawed semen than in the control group (P < 0.05: liquid, 87.5% vs. 70.5%; frozen‐thawed, 89.8% vs. 75.0%). From these results, we concluded that the addition of OXT to the semen extender assisted in sperm transportation from the uterus to the oviduct, which resulted in improved reproductive performance. 相似文献
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This study assessed the effect of oral supplementation with the primary antioxidants and fatty acids involved in spermatogenesis (L-carnitine, selenium, vitamin E, omega-3, and omega-6) on the seminal quality in fresh, cooled, and frozen semen of stallions (n = 8), using a randomized design. The animals were divided into Group I (n = 4) and Group II (n = 4) for a 30-week experiment. The two groups alternated between nutraceutical supplementation and a placebo over the course of the experiment. Semen collections were performed in two sets: once in the middle of the experiment, before the two groups switched treatments, and once at the end. The volume, appearance, sperm concentration, spermatozoa kinetics, and membrane integrity of fresh semen were evaluated. The spermatozoa kinetics and membrane integrity of cooled (for 24, 36, and 48 hours) and frozen semen were also evaluated. No differences were observed in volume, appearance, and sperm concentration between treatment and control. However, compared with placebo, nutraceutical supplementation increased (P < .05) total motility, trajectory speed, as well as plasma and acrosomal membrane integrity in spermatozoa from fresh semen. In cooled semen, nutraceutical treatment also increased (P < .05) total motility, speed, and membrane integrity of spermatozoa compared with the control. In frozen semen, supplementation increased (P < .05) spermatozoa progressive motility and plasma membrane integrity. Our results suggest a positive, synergistic effect of the antioxidant L-carnitine and selenium on spermatozoa kinetics. Similarly, the increase in plasma and acrosomal membrane integrity could be attributed to higher concentrations of polyunsaturated fatty acids (a key cell-membrane component), combined with the prevention of excess lipid peroxidation by antioxidants. In conclusion, supplementation with nutraceuticals containing fatty acids and antioxidants improved the quality of fresh, cooled, and frozen stallion semen. Therefore, nutraceutical use should increase the success of artificial insemination with cooled and cryopreserved semen. 相似文献
58.
对11只狸獭(Myocastorcoypus)用按摩和电刺激相结合的方法人工采精32只次,成功27次,成功率84.4%;射精量为(0.97±0.16)mL,精子密度(7.34±1.49)亿/mL,精子活力0.65±0.12,精子畸形率(8.81±2.51)%,精液pH值6.44±0.16。对诱排公狸施行输精管结扎术,先后给5只母狸人工输精,每只输精2~3次,在输精后40~60d检查,4只受孕,其中有3只顺利产仔,产仔数分别为7只、7只、4只 相似文献
59.
通过对精液冷冻保存的细胞反应原理的阐述 ,指出冷冻保护剂甘油对精液保存具有利弊效应 ,提出精子膜脂组成的差异使得不同品种的精子对冷冻损伤的易感性不同。雌性生殖道解剖结构的品种差异 ,精子形态 ,精子运行机制的细微差异 ,人工授精时间及精子的运行能力 ,采精方式等因素对精液冷冻保存和人工授精的成功有决定性作用。研究精子质膜的生物学特性可解决低活力精子的问题 ,然而这并不能解决冷冻后精子质量的个体差异。对精细胞基因组的研究可以找出这些个体的遗传差异。因此 ,冷冻精子和精原细胞 (用于细胞外注射 )的差异已经成为完整基因组问题。 相似文献
60.
Tetsuji OKAZAKI Shuji YOSHIDA Hisanori TESHIMA Masayuki SHIMADA 《Animal Science Journal》2011,82(3):412-419
In our previous study, seminal plasma effectively suppressed the induction of sperm to capacitation‐like status and acrosome loss during the thawing process. However, because boar seminal plasma is contaminated with various kinds of bacteria and/or viruses, it is necessary to develop a thawing solution without animal‐derived materials. In this study, we focused on the increase of intracellular Ca2+ ([Ca2+]i) in sperm after thawing and the negative effects of sperm qualities. After thawing, the fluorescent intensity of [Ca2+]i indicator, Fluo‐3/AM, and the level of phosphorylated tyrosine residue of protein were increased in the sperm. Next, we investigated whether the addition of Ca2+ chelators (ethylenediaminetetraacetic acid (EDTA) and ethyleneglycoltetraacetic acid (EGTA)) improved post‐thawed sperm motility. When the frozen–thawed sperm were treated with 6 mmol/L EDTA + 6 mmol/L EGTA, sperm motility was significantly increased as compared with control (6 mmol/L EDTA alone) at all incubation periods (P < 0.05). The combinational treatment significantly suppressed the elevation of [Ca2+]i and the tyrosine phosphorylation, which improved the acrosomal status and fertilizing ability in vitro. Furthermore, when the thawing method was applied for artificial insemination, the fertilization rate was significantly higher than control (P < 0.05, 33% vs. 82%). Thus, we conclude that the addition of EDTA + EGTA to thawing solution is a beneficial tool for artificial insemination using frozen–thawed boar sperm. 相似文献