The aim of the study was to examine the in vivo viability of in vitro-produced (IVP) porcine embryos obtained from oocytes matured with thymosin. The research material for this study consisted of immature pig oocytes obtained from ovaries after slaughter and ejaculated semen obtained from one boar. The immature oocytes were cultured in vitro until the metaphase II stage in a medium supplemented with thymosin (TMS). The presumptive zygotes obtained were cultured in vitro for 4-40 hours. The presumptive zygotes and 2-4-cell embryos were evaluated in vivo after transferring them to synchronized recipients. After the transfer of embryos from the experimental group into 2 recipients (50 embryos into each gilt) and the transfer of 50 embryos from the control group into 1 recipient, both gilts that had received embryos obtained by in vitro fertilization of oocytes matured with TMS became pregnant and delivered a total of 16 live piglets. After the transfer of embryos from the control group, no pregnancy was achieved. In conclusion, the results of our preliminary study suggest that the maturation of pig oocytes with thymosin supports the in vivo survival of in vitro produced embryos. It is important to note, that this was the first birth of piglets obtained after transfer of IVP embryos in Poland.

Oocyte maturation is a critical stage in embryo production and female reproduction. The aims of this study were to determine: (i) the mRNA and protein expression of vaspin and its receptor 78-kDa glucose-regulated (GRP78) in porcine cumulus–oocyte complexes (COCs) by real-time PCR and Western blot analysis, respectively, and their localisation by immunofluorescence; and (ii) the effects of vaspin on in vitro oocyte maturation (IVM) and the involvement of mitogen ERK1/2 (MAP3/1)- and AMPKα (PRKAA1)-activated kinases in the studied processes. Porcine COCs were matured in vitro for 22 h or 44 h with vaspin at a dose of 1 ng/mL and nuclear maturation assessed by Hoechst 33342 or DAPI staining and the measurement of progesterone (P4) level in the maturation medium. We showed that vaspin and GRP78 protein expression increased in oocytes and cumulus cells after IVM. Moreover, vaspin enhanced significantly porcine oocyte IVM and P4 concentration, as well as MAP3/1 phosphorylation, while decreasing PRKAA1. Using pharmacological inhibitors of MAP3/1 (PD98059) and PRKAA1 (Compound C), we observed that the effect of vaspin was reversed to the control level by all studied parameters. In conclusion, vaspin, by improving in vitro oocyte maturation via MAP3/1 and PRKAA1 kinase pathways, can be a new factor to improve in vitro fertilisation protocols.

AbstractThis paper presents the current possibilities, state of knowledge and prospects of in vitro production (IVP) of pig embryos, which consists of in vitro oocyte maturation, in vitro fertilization and in vitro embryo culture. In pigs, oocyte maturation is one of the most important stages in the embryo IVP process. It determines the oocyte’s fertilization ability as well as its embryonic development. Through many research studies of the proper selection of oocytes and appropriate maturation medium composition (especially the addition of various supplements), the in vitro maturation of pig oocytes has been significantly improved. Recent studies have demonstrated that modifications of the diluents and in vitro fertilization media can reduce polyspermy. Furthermore, several adjustments of the porcine culture media with the addition of some supplements have enhanced the embryo quality and developmental competence. These updates show the progress of IVP in pigs that has been achieved; however, many problems remain unsolved.

The aim of the study was the preliminary development of laparoscopic transfer of embryos to the uterus in the pig, which can become the alternative for more invasive surgical methods. We proposed the original method of embryo transfer. Donors (n = 40) and recipients (n = 15) of embryos were sows of age of 6-8 months. The estrus cycle of both recipients and donors was routinely synchronized. The experimental animals were divided into two groups. In the first group (10 donors and 3 recipients) embryos were transplanted according to the method described earlier and in the second group (30 donors and 12 recipients) embryos were transplanted according to our own proposed method. As the control group, we used 16 sows after insemination (AI). In animals from both experimental groups pregnancy was diagnosed between 28-31 day after transplantation and in the control group between 28-31 day after insemination. All animals were observed during pregnancy and weaning period in pig farm. Embryos at the development stage of 2-4 cell were obtained surgically and cultured in vitro for 4 days. Obtained blastocysts were transferred to donors. The original set of catheters for blastocysts transfer to pig uterus was constructed. Three trocars were placed in abdominal cavity for inserting endoscope and 2 grasps for uterus stabilization. After uterus stabilization, the slide was inserted into abdomen which was used for putting the needle to puncture uterus. Through this needle catheter with embryos was inserted into the uterus cavity. Embryos were placed by injection into lumen of the one uterine horn. From 12 recipients pregnancy was diagnosed in 6 recipients. From 6 litters, 57 piglets were born. We weaned 41 piglets (71.9%). In our study we obtained 50% efficacy, with the mean number of 9.5 alive piglets in litter and 6.8 weaned piglets. The efficacy of developed method of laparoscopic transfer of porcine embryos allows it to be used in routine practice.

prolactin (prl) is a protein hormone synthesized in and secreted predominantly by lactotroph cells of the anterior pituitary gland. this hormone has been found to stimulate the immune system in animals. Because prolactin secreted in milk by the mother's body is often insufficient, the administration of exogenous prolactin may significantly contribute to improving the health and growth of piglets. The aim of the study was to determine the dose of prolactin administered to newborn piglets to improve their survivability and growth rate. The study used Biolactin solution, produced on a semi-technical scale by FZNP Biochefa, which was administered per os to newborn piglets at a dose of 0.1, 0.5 and 1.0 mg PRL/kg body weight. NaCl physiological saline was used as a control. The number of piglets born alive, piglet body weight and mortality from birth to 21 and 28 days of age (weaning) were monitored. The study involved 98 litters (1197 piglets), which were divided into 3 experimental and 3 control groups. The experiment showed a positive effect of exogenous prolactin administered to newborn piglets on reducing their mortality and on increasing their birth to weaning growth rate. A dose of 0.5 mg PRL/kg body weight turned out to be optimal.