The aim of the study was to develop a method of laparoscopic embryo transfer in pigs and to compare different variants of this method. Two catheter diameters (1.6 mm and 1.0 mm), the method and site of embryo deposition (oviduct or uterus), the embryo development stage (2 – 4 cell or blastocyst), the method for oviduct or uterus stabilization, the potential for cryopreserved embryo transfer, the developmental potential of the embryos after transfer to the oviduct, patomorphology of the oviduct after transfer and possible clinical complications were taken into consideration. Two studies compared two variants of transfer to the uterus, and five variants of transfer to the fallopian tube. The transfer of embryos by the infundibulum may be of limited use due to handling problems and very low efficiency (pregnancy was not achieved). Very low efficiency was shown after transfer of vitrified embryos. Transfer to the fallopian tube by puncture of the fallopian tube, regardless of the developmental stage of the embryo, is the recommended method of embryo transfer. The histopathological examination of the fallopian tube revealed possible changes within the puncture site. The numerous clinical complications observed did not affect the effectiveness of the method.

Feeder cells can promote cell proliferation and help overcome the developmental arrest of early embryos by producing growth factors. The objective of this study was to evaluate the effects of feeder cells on the development of all single porcine parthenogenetic embryos in vitro. Firstly, we showed that the cleavage and blastocyst formation rate of all single procine parthenogenetic embryos co-cultured with feeder cells increased in contrast to those cultured without feeder cells (p<0.05). However, no statistically significant differences were observed between the blastocyst formation rate in the embryos co-cultured with 3 different kinds feeder cells namely oviduct epithelial feeder cells, granulose feeder cells and porcine fetal fibroblast feeder cells (p>0.05). Secondly, highly significant differences were observed between the cleavage and blastocyst formation rate (p<0.05) when the embryos were co-cultured with oviduct epithelial feeder cells in different volume drops ranging from 3 to 20 μL and the cleavage rate were the highest when cultured in 5 μL drops. Thirdly, the tempospacial pattern of the development of single embryos co-cultured with oviduct epithelial feeder cells was consistent with that of traditional multi-embryo culture, indicating that the co-culturing does not affect the developmental competence of the porcine parthenogenetic embryos. Finally, highly significant differences were observed between the cleavage and blastocyst formation rate with and without zona pellucida in vitro (p<0.05). In this study, a new adaption of in vitro co-culture of single porcine parthenogenetic embryos using feeder cells has been successfully established and this will facilitate further investigations to discover the mechanistic mode of developmental arrest of porcine embryos.

In this study, female gametophytes of Silene muradica, which is a gynodioecious species, were examined histologically. Buds and blossoms of S. muradica were used as the research material. They were collected in the Sivas province (Turkey) in July 2019, and fixed with ethanol:acetic acid solution (3:1, v/v). Flower parts were dissected under a stereo microscope. They were dehydrated in rising alcohol series and then embedded in Historesin. The sections were taken by a rotary microtome and stained with 0.5% Toluidine blue O. The ovary of S. muradica has three carpels and a single chamber, the ovules are arranged on a central column. The mature ovule is of the campylotropous type, crassinucellate and bitegmig. The megaspore mother cell undergoes regular meiotic division and forms a linear megaspore tetrad after meiosis. The development of the embryo sac is monosporic. The chalazal megaspore is functional and the others degenerate. The mature embryo sac is eight-nucleated and of the Polygonum type. The synergid cells and the egg cell are completely surrounded by the cell wall. Antipodal cells are temporary cells, which degenerate immediately after fertilization. Before fertilization, polar nuclei are fused in the central cell and form the secondary nucleus. The endosperm development is of the nuclear type. Nucellar tissue is permanent and forms perisperm in mature seeds. The embryo development is of the Caryophyllad type. In this study, the development of the female gametophyte of S. muradica, which was determined to be a gynodioecious species, was reported for the first time.

The article presents the main discoveries of Prof. Andrzej K. Tarkowski, which proved to be fundamental for modern mammalian developmental biology and also for progress in animal breeding and assisted reproduction. Among his achievements the most important are: the demonstration of regulative abilities of blastomeres isolated from early mammalian embryos, generation of first chimaeric mice, studies on mammalian parthenogenesis and establishment of blastomere electrofusion technique for production of tetraploid embryos. Studies on nucleocytoplasmic interactions in germ cells and early embryos contributed substantially to the development of mammalian cloning. Prof. Tarkowski’s work and discoveries provided a tremendous input to the contemporary developmental biology of mammals.

Culture gas atmosphere is one of the most important factors affecting embryo development in vitro. The main objective of this study was to compare the effects of CO concentration on the subsequent pre-implantation developmental capacity of pig embryos in vitro, including embryos obtained via parthenogenesis, in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI). Pig embryos were developed in four different CO2 concentrations in air: 3%, 5%, 10%, or 15%. The cleavage rate of pig parthenogenetic, IVF, or ICSI embryos developed in CO2 concen- trations under 5% was the highest. There were no significant differences in the oocyte cleavage rate in ICSI embryos in CO2 concentrations under 3% and 5% (p>0.05). However, as CO2 levels increased (up to 15%) the blastocyst output on day 7, from parthenogenetic, IVF, and ICSI em- bryos, decreased to 0%. These findings demonstrate that CO2 positively affects the developmen- tal capacity of pig embryos. However, high or low CO2 levels do not significantly improve the developmental capacity of pig embryos. The best results were obtained for all of the pig embryos at a 5% CO2 concentration.

To understand the molecular mechanism controlling in vitro plant morphogenesis, a culture system enabling induction of alternative morphogenic pathways (somatic embryogenesis, SE; shoot organogenesis, ORG) in a well defined population of somatic cells is needed. Arabidopsis is the most useful model plant for genomic studies, but a system in which SE or ORG can be induced alternatively in the same type of explant has not been proposed. Immature zygotic embryos (IZEs) of Arabidopsis provide the only explants with embryogenic potential, and have been recommended for studying mechanisms of SE induced in vitro. This study was aimed at defining culture conditions promoting induction of alternative morphogenic pathways: shoot ORG in IZE explants. The established protocol involves pretreatment of IZE explants with liquid auxin-rich callus induction (CIM) medium, followed by subculture on solid cytokinin-rich shoot induction medium (SIM). The method enables efficient shoot induction in Columbia (Col-0) and Wassilewskija (Ws), genotypes commonly used in molecular studies. During 3 weeks of culture up to 90% of Col-0 and 70% of Ws explants regenerated shoots via an indirect morphogenic pathway. We analyzed the qRT-PCR expression patterns of the LEC (LEC1, LEC2 and FUS3) genes, the key regulators of Arabidopsis embryogenesis, in the IZE explants induced to promote shoot ORG. The sharp decline of LEC expression on SIM medium confirmed that culture of Arabidopsis IZE explants enables experimental manipulation of the morphogenic response of somatic cells. A scheme illustrating various in vitro morphogenic responses of IZEs in relation to hormonal treatment is presented.

Our study involved the first-ever evaluation of the performance of anther culture and wheat × maize hybridization techniques in producing haploids or doubled haploids as a result of spontaneous doubling of the chromosome number during androgenesis in plants from 30 wheat genotypes including ancient, local and modern types. The results indicated that the best induction rates of androgenic structures and haploid embryos for the hexaploid and tetraploid wheat genotypes were obtained with anther culture and wheat × maize hybridization, respectively. Whereas only one regenerated plant from 15 genotypes of tetraploid wheat was obtained, 13 plants were regenerated from 15 genotypes of hexaploid wheat. Moreover, haploid embryos obtained in wheat × maize hybridization 60 and 100% green plants regenerated in relation to the number of the cultured haploid embryos. Genotypes with high induction capacity to produce androgenic structure or haploid embryos did not have desired haploid plantlets regeneration capacity and vice-versa. However, with both methods, hexaploid wheat genotypes had a considerable ability to produce green plants. Doubled haploid plants were obtained from ancient and local wheat genotypes by both methods, but not from modern wheat. Those genotypes can be used as parents in future wheat breeding programs and new varieties may be obtained by selecting pure lines in wheat populations