Sex ratio and conception rates of fresh/vitrified embryos at different developmental stages by ovum pick up in Hanwoo cows.

Embryo transfer plays a crucial role in enhancing the breeding value of livestock; it has been applied in Hanwoo cattle, which is a popular breed for beef production in Korea. Both -derived (IVD) and -produced (IVP) embryos are used for this purpose; however, IVP embryos have been preferred recently owing to advancements in ovum pick-up (OPU) technology and genomic selection. Despite technological advancements, comprehensive data on large-scale OPU/IVEP/embryo transfer in Hanwoo cows are lacking.

Germline transmission of MSTN knockout cattle via CRISPR-Cas9.

Although the production of several founder animals (F0) for gene editing in livestock has been reported in cattle, very few studies have assessed germline transmission to the next generation due to the long sexual maturation and gestation periods. The present study aimed to assess the germline transmission of MSTN mutations (-12bps deletion) in MSTN mutant F0 male and female cattle. For this purpose, oocytes and semen were collected after the sexual maturation of MSTN cattle, and embryos produced by in vitro fertilization were analyzed.

Failure to maintain full-term pregnancies in pig carrying klotho monoallelic knockout fetuses.

Background: Small animals that show a deficiency in klotho exhibit extremely shortened life span with multiple aging-like phenotypes. However, limited information is available on the function of klotho in large animals such as pigs.

Results: In an attempt to produce klotho knockout pigs, an sgRNA specific for klotho (targeting exon 3) was designed and Cas9-sgRNA ribonucleoproteins were transfected into porcine fibroblasts.

Establishment of Transgenic Porcine Fibroblasts Expressing a Human klotho Gene and Its Effects on Gene Expression and Preimplantation Development of Cloned Embryos.

Even though the functions of the klotho gene in aging of small animals such as mice have been well investigated, studies using large animal models such as pigs, which have many similarities to humans, have been limited due to the absence of cell lines or animal models. Therefore, the objective of this study was to generate porcine cell lines overexpressing human klotho (hKlotho) and tetracycline (Tet)-inducible hKlotho and to produce cloned embryos from these cell lines. We designed vectors for hKlotho overexpression (CA-Klotho) under control of CMV enhancer/chicken β-actin (CAG) promoter and Tet-inducible hKlotho overexpression (Tet-Klotho, under control of doxycycline-dependent promoter).

Cloned foal derived from in vivo matured horse oocytes aspirated by the short disposable needle system.

Transvaginal ultrasound-guided follicle aspiration is one method of obtaining recipient oocytes for equine somatic cell nuclear transfer (SCNT). This study was conducted: (1) to evaluate the possibility of oocyte aspiration from pre-ovulatory follicles using a short disposable needle system (14-G) by comparing the oocyte recovery rate with that of a long double lumen needle (12-G); (2) to investigate the developmental competence of recovered oocytes after SCNT and embryo transfer. The recovery rates with the short disposable needle vs.

Sequential treatment with resveratrol-trolox improves development of porcine embryos derived from parthenogenetic activation and somatic cell nuclear transfer.

We investigated the effect of resveratrol supplementation during IVM and/or trolox during IVC on the development of porcine embryos derived from parthenogenetic activation (PA) and SCNT. In this study, we evaluated intracellular glutathione (GSH) and reactive oxygen species (ROS) levels, gene expression in blastocysts, and embryonic development after PA and SCNT. To determine the combined effects of resveratrol during IVM and trolox during IVC on PA embryos, we selected optimal concentrations (2 μM of resveratrol and 200 μM of trolox) and designed four groups: (1) control, (2) resveratrol, (3) trolox, and (4) combined.

Proposed Motor Scoring System in a Porcine Model of Parkinson's Disease induced by Chronic Subcutaneous Injection of MPTP.

Destruction of dopaminergic neurons in the substantia nigra pars compacta (SNpc) is a common pathophysiology of Parkinson's disease (PD). Characteristics of PD patients include bradykinesia, muscle rigidity, tremor at rest and disturbances in balance. For about four decades, PD animal models have been produced by toxin-induced or gene-modified techniques.

Influence of factors during superovulation on embryo production in Korean Holstein cattle.

The aim of this study was to investigate the influence of key parameters (donor parity, milk production, post-parturient day, season and milk recording data) associated with efficiency of embryo recovery (ER) in Holstein cattle. Elite Holstein cows and heifers were selected for ER, while Holstein heifers were used as recipients. The numbers of transferable embryos (TEs) produced were not significantly different when analyzed in terms of donor parity, milk production, postparturient day and season.

Prolonged interval between fusion and activation impairs embryonic development by inducing chromosome scattering and nuclear aneuploidy in pig somatic cell nuclear transfer.

The aim of the present study was to examine the effect of various intervals between electrofusion and activation (FA interval) on the nuclear remodelling and development of somatic cell nuclear transfer (SCNT) embryos in pigs. Reconstructed oocytes were activated at 0 (simultaneous fusion and activation; SFA), 1, 2 and 3 h (delayed activation) after electrofusion; these groups were designated as DA1, DA2 and DA3, respectively. When oocyte nuclear status was examined at 0.

Post-activation treatment with demecolcine improves development of somatic cell nuclear transfer embryos in pigs by modifying the remodeling of donor nuclei.

The objective of this study was to examine the effect of cytochalasin B (CB) and/or demecolcine (Dc) on the remodeling of donor nuclei, nuclear ploidy, and development of somatic cell nuclear transfer (SCNT) and parthenogenetic (PA) pig embryos. SCNT and PA oocytes were either untreated (control), or treated with CB, Dc, or both CB and Dc after electric activation, and then cultured or transferred to surrogates. In SCNT, blastocyst formation was higher after treatment with CB and/or Dc (26-28%) than in the controls (16%).

Autologous somatic cell nuclear transfer in pigs using recipient oocytes and donor cells from the same animal.

The objective of the present study was to examine the feasibility of the production of autologous porcine somatic cell nuclear transfer (SCNT) blastocysts using oocytes and donor cells from slaughtered ovaries. Therefore, we attempted to optimize autologous SCNT by examining the effects of electrical fusion conditions and donor cell type on cell fusion and the development of SCNT embryos. Four types of donor cells were used: 1) denuded cumulus cells (DCCs) collected from in vitro-matured (IVM) oocytes; 2) cumulus cells collected from oocytes after 22 h of IVM and cultured for 18 h (CCCs); 3) follicular cells obtained from follicular contents and cultured for 40 h (CFCs); and 4) adult skin fibroblasts.

Modification of maturation condition improves oocyte maturation and in vitro development of somatic cell nuclear transfer pig embryos.

This study examined effects on the developmental competence of pig oocytes after somatic cell nuclear transfer (SCNT) or parthenogenetic activation (PA) of : 1) co-culturing of oocytes with follicular shell pieces (FSP) during in vitro maturation (IVM); 2) different durations of maturation; and 3) defined maturation medium supplemented with polyvinyl alcohol (PVA; control), pig follicular fluid (pFF), cysteamine (CYS), or beta-mercaptoethanol (beta-ME). The proportion of metaphase II oocytes was increased (p < 0.05) by co-culturing with FSP compared to control oocytes (98% vs.