Somatic Embryogenesis and Plant Regeneration from Tritordeum

Regeneration of plants by somatic embryogenesis from immature embryos of hexaploid tritordeum (AABBH^chH^ch, amphiploid Hordeum chilense×Triticum turgidum conv. durum) and durum wheat (Triticum tergidum) was induced on MS medium supplemented with different 2.4-D concentrations. Well-defined embryoids were formed with a high frequency on the scutellar callus from 1 or 2 weeks onwards and plantlets were developed from them. In the best cases from one single explant more than 100 plants could be obtained. Plants were also regenerated by somatic embryogenesis from inflorescences of Hordeum chilense×Triticum turgiditm conv. durum hybrid and its respective hexa-amphiploid. With regard to callus induction and regenerative ability, evident differences between hexa- and octoploid (H. chilense×T. aestivum) tritordeum were found, the latter showing a very low response.     

兰藤注射液体外抗新城疫病毒的实验研究

采用鸡胚培养法和血凝抑制试验测定了兰藤注射液对新城疫病毒的抑制作用.结果表明,中药对鸡胚无毒性作用;在药物与病毒同时接种后,可抑制新城疫病毒在鸡胚中的增殖.     

Embryo transfer in subfertile mares

Four subfertile mares (at least 2 barren years) were used as donors in an embryo transfer program. The embryo recovery rate was 50%, varying between 0-100. The transfer of 9 embryos resulted in the pregnancy rate of 44%. The efficiency of embryo transfer using subfertile mares is low. In this material 20% of flushings resulted in a pregnancy.     

Bactericidal activity of cecropin B and cecropin P1 expressed in fish cells (CHSE-214): application in controlling fish bacterial pathogens

Cecropins are a group of antimicrobial peptides which have bactericidal activity against a broad range of bacteria. To date, the cecropins used in a variety of studies were either purified from their natural source or obtained by chemical synthesis. The present study was conducted to test whether bactericidally active cecropins could be expressed in a fish cell line. For this purpose, Chinook salmon embryo cells (CHSE-214) were transfected with cecropin transgene constructs: Hyalophora cecropia preprocecropin B, procecropin B, cecropin B, and porcine P₁ cecropin. From the transfected cells, single cell clones were selected and screened for the presence of cecropin gene constructs by PCR amplification. The expression of the cecropin transgene in the PCR positive clones was determined by RT-PCR reaction. Southern blot hybridization results showed that the cecropin gene constructs were integrated into the genome in a multiple integration pattern. Bactericidal activity of the cecropins, synthesized from transgene constructs, was detected using inhibition zone assay for fish pathogenic bacteria: Aeromonas hydrophila, Pseudomonas fluorescens, and Vibrio anguillarum. Cecropin antimicrobial peptides produced in CHSE-214 cells possess bactericidal activity against these three fish pathogenic bacteria.     

波尔山羊胚胎移植试验

应用FSH对8只供体波尔山羊进行了超排处理。在放栓的第9～12天,连续4d采用递减量肌肉注射FSH。结果有6只发情,同期发情率为75%。这6只羊配种后均采胚成功,共采胚83枚,只均13.8±7.36枚,其中可用胚75枚,只均12.5±5.99枚,可用胚胎率为90.36%(75/83)。将36枚可用胚移植受体奶山羊32只,妊娠18只,妊娠率56.25%(18/32)。     

山羊冻胚分割试验

将冷冻-解冻后的琼脂包被孵出胚泡分两组,分别置于12％蔗糖液(A)和磷酸缓冲液(B)中进行2分切割。在体外培养12小时后,A、B两组的半胚发育率分别为68.9％(31/45)和58.3％(35/60)。A组的冻胚分割效果显著好于B组(P<0.05)。将早期囊胚、扩张囊胚、孵出胚泡和琼脂包被孵出胚泡冷冻-解冻后,在12％蔗糖液中分割为2(A、B、C、D组)。在体外培养12～24小时后,A、B、C、D4组的半胚发育率分别为47％(14/30)、 50％(15/30)、27％(8/30)和70％(21/30)。D组的冻胚分割效果显著好于A、B两组(P<0.05)极显著地好于C组(P<0.01)。将5枚在冷冻前用琼脂包被的孵出胚泡在12％蔗糖液中分割为二后移植于5只受体,结果有4只妊娠,共产半胚羔6只,其中2对为同卵双生。本研究证明,在蔗糖液中分割冻胚可提高半胚体外成活率;分割从琼脂释放出的解冻孵出胚泡可提高山羊冻胚分割的效果。     

常山胡柚胚型的初步观察

检视常山胡柚种子４６９７粒，结果表明：单胚１８７８粒，占４０．０％；多胚２８１９粘，占６０．０％。受检１１个单株和４个人工授粉组合的种子，均未发现全部是单胚或全部是多胚的单株或组合，表明常山胡柚种子为单多胚混合型。     

Culture of frozen/thawed Bovine Demi-Embryos with Bovine Oviduct Epithelial Cells*

A method for in vitro culture of splitted frozen/thawed bovine embryos is described. These demi-embryos are of a low viability, but they survive the treatments, which lead to the final cultivation. The culture system gave a development of 41%of demi-embryos and 75 % of the whole embryos, and it is concluded, that this system is usable to culture demi-embryos.     

砧木和接穗苗龄对顶插接法西瓜嫁接苗生长发育的影响

采用二因素完全随机设计,研究不同砧木和接穗苗龄对顶插接法西瓜嫁接苗成活率、嫁接苗形态指标、叶绿素含量及根系活力的影响。结果发现,随着砧木苗龄的增大,嫁接苗的根系活力均呈先增加后降低的趋势,叶片数、接穗干质量、嫁接成活率、茎粗、叶片叶绿素含量的变化各异;随着接穗苗龄的增大,嫁接苗的嫁接成活率、叶片数、茎粗、接穗干质量、叶片叶绿素含量、根系活力均表现为先增高后降低的趋势。采用隶属函数法综合评价西瓜嫁接苗的质量,发现接穗苗龄9~13d、砧木苗龄11~15 d的西瓜嫁接苗隶属函数值较大,是适合西瓜顶插接法的接穗和砧木最佳苗龄时期。     

Laparoscopy vs. laparotomy for embryo transfer to produce transgenic goats (Capra hircus)

This study was performed to produce transgenic Korean native goat (Capra hircus) by laparoscopic embryo transfer (ET) to overcome the limitations of ET performed by laparotomy. Transgenic embryos were produced by DNA pronuclear microinjection of in vivo zygotes. The recipient goats were synchronized for estrus by using an introvaginal progesterone devices as a controlled internal drug-releasing insert (CIDR) for 13 days and injection of 400 IU PMSG 48 h before removal of the insert. Embryos were transferred on day 3 and 4 after removal of the insert. Recipient goats were deprived of feed for 48 h, then suspended in a laparotomy cradle at an angle of 45°. After obtaining a sufficient pneumoperitoneum, the laparoscope and forceps were inserted abdominally through 5 mm trocar sleeves. Examination of the ovaries and uterus was performed and then 213 embryos were transferred into the oviducts via the infundibula of 76 recipient goats. To compare pregnancy rates, ET was also performed by laparotomy in 82 recipient goats. The pregnancies in the recipient goats were diagnosed by ultrasound on day 30 after embryo transfer. The pregnancy rate with laparoscopic ET was significantly higher than with ET performed by laparotomy (46.1% vs. 28.6%, p < 0.05). In addition, the pregnancy rates were compared between ovulated and non-ovulated ovaries of the recipient goats in the laparoscopic ET group. No significant difference was observed between the pregnancy rates of ovulated and non-ovulated ovaries (41.3% vs. 33.3%, p < 0.05) suggesting that ET may also be possible in non-ovulated recipients through artificial rupture of Graafian follicles. These results suggest that laparoscopic ET is a highly efficient method for the transfer of goat embryos.