Vitamin C Synergistically Enhances Protective Effects of Vitamin E Against Preantral Follicle Degeneration of Ovine Vitrified/Warmed Ovarian Tissue.

This study aimed to evaluate whether the addition of vitamins E and C as two conventional antioxidants improves the cryotolerance of preantral follicles enclosed in ovine ovarian tissue slices. For this purpose, ovarian slices were obtained from abattoired juvenile lambs and randomly distributed to the following groups: fresh, toxicity, vitrified (control), and three treatment groups in two experiments. Vitamin E, vitamin C, or vitamin E + C was added to the vitrification media alone in the first experiment and added to all vitrification, warming, and culture media in the second experiment.

Polyvinyl alcohol addition to freezing extender can improve the post-thaw quality, longevity and in vitro fertility of ram epididymal spermatozoa.

Recovering and cryopreserving epididymal spermatozoa are suitable methods for preserving the genetic potential of livestock and endangered species. Regarding encouraging reports on the use of polyvinyl alcohol (PVA) in cryopreserving various cell types, we conducted this study to examine the impact of PVA on the post-thaw quality, longevity, and in vitro fertility of ram epididymal sperm. In the first experiment, ram epididymal spermatozoa were frozen in extenders containing 6 % glycerol and 0, 0.

Development and evaluation of an injectable slow-release progesterone formulation for estrus synchronization in ewes out of the breeding season.

This study was aimed at developing a type of slow-release progesterone micro-particles useable in a single intramuscular injection for estrus synchronization in non-breeding season ewes. A total of 66 ewes were randomly assigned into four groups: CIDR (n = 16): exposed to intravaginal CIDR for 12 days, and three experimental groups, i.e.

Ram epididymal sperm frozen in an extender containing ethylene glycol have higher post-thaw longevity and in vitro fertility.

Background: Establishing an efficient, simple and inexpensive method for freezing ram epididymal sperm so that the quality and fertility of spermatozoa could be maintained for a longer period after thawing is of great practical value.

Objectives: To optimize freezing and thawing protocol for ram epididymal sperm using either ethylene glycol (EG) or glycerol (GLY) as cryoprotectants (CPAs). Then, to evaluate the post-thaw longevity and in vitro fertility of spermatozoa that were frozen and thawed according to the optimized protocol.

Human amniotic membrane stem cells' conditioned medium has better support for in-vitro production of bovine embryos than FBS.

Apart from oocyte quality, the media used has a significant effect on the production and quality of blastocysts produced in vitro. This study was designed to evaluate the replacement of serum with human amniotic membrane stem cells' conditioned medium (hAMSCs-CM) during bovine embryo culture on the quantity and quality of produced blastocysts. The in-vitro-produced embryos on the third day of IVC were randomly divided into the following culture groups: SOFaa + 5% FBS (Control), SOFaa + 5% hAMSCs-CM (5% CM), SOFaa + 2.

The effect of chemical treatment of the sheep embryo zona pellucida on the ability of blastocysts to hatch after vitrification and warming.

Background: The embryo release from the zona pellucida is of prerequisites of successful implantation.

Objectives: Regarding the negative impact of embryo cryopreservation on the blastocysts hatchability, the aim of the present study was to investigate the effects of treating embryonic zona pellucida with pronase or acidic Tyrode's solution (ATS) before morula formation on the viability, freezability, and hatchability of vitrified-warmed resulted blastocysts.

Methods: In the first experiment, the zona pellucida of 3- and 4-day-old embryos were treated with the above compounds for 30 or 45 s.

Embryo co-culture with bovine amniotic membrane stem cells can enhance the cryo-survival of IVF-derived bovine blastocysts comparable with co-culture with bovine oviduct epithelial cells.

Culture conditions have a profound effect on the quality of in vitro-produced embryos. Co-culturing embryos with somatic cells has some beneficial effects on embryonic development. Considering the ability of stem cells to secrete a broad range of growth factors with different biological activities, we hypothesized that bovine amniotic membrane stem cells (bAMSCs) might be superior to bovine oviduct epithelial cells (BOECs) in supporting embryonic development and enhancing their cryo-survival.

Effects of cryopreservation on stallion sperm protamine messenger RNAs.

Protamines substitute DNA-binding histones during late spermatogenesis in sperm nucleus. Stallion sperm contains all three variants of these arginine-rich and positively charged nuclear proteins (P1, P2 and P3). Two variants of protamine-2, that is P2 and P3, constitute approximately 15% of the entire protamine content.

Sericin Ameliorates the Capacitation State and Chromatin Integrity of Frozen-Thawed Stallion Spermatozoa by Reducing Oxidative Stress.

Background: In the process of sperm cryopreservation, apart from cryoinjury, the production of Reactive Oxygen Species (ROS) can adversely affect the integrity of chromatin and cellular membranes. Addition of natural antioxidants to freezing medium is an approach to reduce the destructive effects of ROS on sperm.

Methods: In this study, during 60 of cooling process, the ejaculates of five stallions were diluted in the following media: INRA 82 medium as Control (C), INRA 82 medium supplemented with 0.

Antioxidants and glycine can improve the developmental competence of vitrified/warmed ovine immature oocytes.

Despite the numerous potential applications of oocyte cryopreservation, the poor success rate has limited its practical applications. In livestock, particularly in ovine, the oocytes have low developmental competence following vitrification/warming process. Considering the occurrence of osmotic and oxidative stresses during the vitrification/warming process, the application of antioxidants and osmolytes may improve the developmental competence of vitrified/warmed oocytes.

Male Pronuclear Formation and Embryo Development Following Intracytoplasmic Injection of Ovine Pretreated Sperm.

Background: Failure of Male Pronucleus (MPN) formation is a major concern in the success of Intracytoplasmic Sperm Injection (ICSI) in some species. Despite the conducted unsuccessful efforts to improve ICSI efficiency in ovine, the present study was aimed to improve MPN formation and embryo development in ovine ICSI procedure through accompaniment of sperm pretreatment with co-injection of some compounds.

Methods: In experiment 1, sperm were treated with either 2-mercaptoethanol (2ME), glutathione (GSH), or DTT (dithiothreitol) in combination with Heparin (Hep).

Suspects as One of the Most Important Causes of Abortion in Large Dairy Farms in Isfahan, Iran.

Background: This study aimed to reveal the serological prevalence of in large dairy farms in Isfahan Province, central Iran.

Methods: Serum samples were collected from 1500 cattle living in four large dairy farms in Isfahan Province, Iran during 2014-2015 and examined for anti IgG antibodies. Overall, 113 serum samples were also collected from the dogs living in these areas; suspecting to be risk factors for this infection.

Evidence of Oocyte Polarity in Bovine; Implications for Intracytoplasmic Sperm Injection and Somatic Cell Nuclear Transfer.

Objectives: We recently demonstrated spatial regionalization of maternal transcripts and proteins within unfertilized ovine oocyte. Here, we investigated the likelihood of oocyte polarity for the first time in bovine.

Materials And Methods: In this experimental study, in vitro matured bovine oocytes were used for manual bisection [into oocyte halve that were near-to (HNS) and far-from (FS) spindle] or trisection [into MII-spindle (S), the spindle-side half (NS), and the distal half unassociated with the spindle (FS)].

Platelet-rich plasma promotes the development of isolated human primordial and primary follicles to the preantral stage.

This study aimed to assess the effects of platelet-rich plasma (PRP) on growth and survival of isolated early human follicles in a three-dimensional culture system. After fresh and vitrified-warmed ovarian tissue was digested, isolated early preantral follicles and ovarian cells were separately encapsulated in 1% alginate (w/v). The encapsulated follicles and ovarian cells were cultured together in a medium supplemented with foetal bovine serum (FBS), PRP, PRP + FBS, or human serum albumin (HSA) for 10 days.

The effect of amniotic membrane stem cells as donor nucleus on gene expression in reconstructed bovine oocytes.

Nuclear reprogramming of a differentiated cell in somatic cell nuclear transfer (SCNT) is a major concern in cloning procedures. Indeed, the nucleus of the donor cell often fails to express the genes which are a prerequisite for normal early embryo development. This study was aimed to evaluate the developmental competence and the expression pattern of some reprogramming related genes in bovine cloned embryos reconstructed with amniotic membrane stem cells (AMSCs) in comparison with those reconstructed with mesenchymal stem cells (MSCs) and adult fibroblasts (AF) as well as with in vitro fertilized (IVF) oocytes.

Overexpression of signal transducers and activators of transcription in embryos derived from vitrified oocytes negatively affect E-cadherin expression and embryo development.

Vitrification apart from all drawbacks on oocyte ultra-structure can affect the oocyte mRNA content. Among those evaluated transcripts, no data is available regarding the effect of vitrification on signal transducer and activator of transcription (STAT3) expression in oocytes and the resulting preimplantation embryos. Considering the bidirectional relationship between E-cadherin (CDH1) and STAT3 and the adverse effect of cryopreservation on adherent junctions, we aimed to ascertain to what extent STAT3 and CDH1 genes expression is affected by vitrification in oocytes and the resulting embryos.

Male Pronuclear Formation using Dog Sperm Derived from Ectopic Testicular Xenografts, Testis, and Epididymis.

Background: Testis tissue xenografting and the resultant sperm in a xenograft may provide a unique approach to rescue the genetic material of males that die prematurely and is a model for the study of human spermatogenesis and can represent an alternative approach for fertility preservation in cancer patients. This study was aimed to evaluate the xenogenic dog sperm in formation of male pronucleus following injection into the sheep oocytes.

Methods: The in vitro matured slaughterhouse derived sheep oocytes were subjected to Intracytoplasmic Sperm Injection (ICSI) with epididymal, testicular, and xenogenic dog sperm.

Acephalous lamb from an in vitro-produced sheep embryo.

This is the first report of an acephalous lamb from the transfer of an in vitro-produced sheep embryo. Twelve in vitro-fertilized embryos were transferred to 4 recipient ewes (3 embryos/ewe). Two ewes remained pregnant: one delivered a normal female lamb, the other a male acephalous lamb.