Showing papers in "Theriogenology in 2016"

TL;DR: There are varied causes for pregnancy losses during each pivotal period that correspond to key physiological changes in the embryo, uterine environment, and ovary and strategies to reduce these losses are likely to require a multifaceted approach using rational methods that target the critical physiology in each pivotalperiod.

TL;DR: The present work summarizes the principles of cryoinjury and the relevance of permeating and nonpermeating cryoprotective agents and speculates with new research horizons on the preservation of boar sperm, such as vitrification and freeze-drying.

TL;DR: New approaches for increasing rates of genetic improvement through use of AI are aimed at methods to continue to lower the number of sperm in an AI dose and reducing the number to use of a single, fixed-time AI after ovulation induction.

TL;DR: Signaling between the two cell types most likely continues after ovulation and even fertilization; however, this too is largely undefined but may play roles in substrate transport, sperm chemotaxis and "trapping", and potential signaling to the rest of the reproductive tract.

TL;DR: The various cryopreservation and vitrification technologies that are used in both humans and other animals are reviewed and the most recent innovations in vitrification are discussed with a particular emphasis on their applicability to animal embryology.

TL;DR: Changes of DNA integrity in frozen sperm seem to be related to synthesis of H2O2 but not to sperm viability and synthesis of other reactive oxygen species.

TL;DR: Various models of transgenic mice and sheep carrying natural loss-of-function mutations associated with sterility have established that the oocyte-derived factors, bone morphogenetic protein (BMP) 15 and growth differentiation factor 9 orchestrate follicle development, support cumulus metabolism and maturation and participate in oocyte meiosis arrest.

TL;DR: Current knowledge on epigenetic reprogramming after use of SCNT in livestock is reviewed, with emphasis on gene-specific and global DNA methylation, imprinting, X-chromosome inactivation, and telomere length restoration in early development.

TL;DR: Treatments to resynchronize ovulation for a second FTAI in nonpregnant cows have provided the opportunity to do sequential inseminations and achieve high P/AI in a breeding season, reducing or even eliminating the need for clean-up bulls.

TL;DR: Differences in ovarian function related or not to nutrition between these two genetic groups are very consistent and may be related to the influence of metabolic hormones such as insulin and IGF1.

TL;DR: Effective bacterial control strategies are necessary to minimize the risk of bacteria contaminating extended semen doses, including monitoring programs designed for quick detection and intervention, should the need arise.

TL;DR: The comprehensive analyses possible with liquid chromatography tandem mass spectrometry illuminate the key physiological and developmental transitions that make equine gestation unique.

TL;DR: Anovulation leads to major shifts in gene expression in elongated conceptuses during preimplantation stages of pregnancy, and one approach to minimize the impact of anovulation on fertility is supplementation with progesterone during recruitment, selection and final stages of development of the preovulatory follicle.

TL;DR: It is speculated that the oviduct may also be capable of distinguishing other genetically encoded properties of individual spermatozoa and that there must ultimately be a huge payoff in terms of selective animal breeding.

TL;DR: It is reported that estrous expression at the time of AI favorably altered the gene expression profile in reproductive tissues during the preimplantation phase toward a more receptive state to the elongating conceptus.

TL;DR: A reproductively efficient beef cow herd will be fundamental to meeting the protein and specifically, red meat demand of an ever increasing global population, but attaining a high level of reproductive efficiency is underpinned by producers being cognizant of and achieving many key targets throughout the production cycle and requires considerable technical competency.

TL;DR: The results report that the CRISPR/Cas9 system can be applied for site-specific edition of the bovine genome, which could have a great impact on the development of large animals resistant to important zoonotic diseases.

TL;DR: In this article, the authors used a logistic regression model to predict pregnancy maintenance until Day 100 of gestation, and found that pregnant cows that maintained a pregnancy from days 28 to 100 had significantly higher circulating concentrations of bPAGs compared with cows that did not maintain a pregnancy (embryonic mortality [EM]) until day 100 (n = 89).

TL;DR: These epigenetic indexes could be used as damage markers of oocytes vitrification during early embryonic development, which offers a new insight to assess oocyte vitrification.

TL;DR: Research regarding prophylactic systemic immunization of bulls and cows with antigens of T foetus and C fetus venerealis and their efficacy in preventing or clearing preexisting infections in the genital tract is reviewed.

TL;DR: A highly concentrated and fluctuating hormonal environment was evidenced in the bovine OF, and could be useful to improve media for IVF, embryo development, and culture of oviductal cells.

TL;DR: AI is commercially applied worldwide to breed pigs, yielding fertility outcomes similar to those of natural mating, but it is not fully efficient, as only liquid-stored semen is used, with a single boar inseminating about 2000 sows yearly.

TL;DR: Early embryonic development is compromised in high-producing dairy cows, as observed by most embryonic losses occurring during the first 2 weeks after fertilization and may be linked to compromised oocyte quality due to a poor follicular microenvironment, suboptimal reproductive tract environment for the embryo, and/or inadequate maternal-embryonic communication.

TL;DR: The aim of this review is to highlight the main mechanisms of epigenetic remodeling that ensue after fertilization in mammals and reveal active and passive mechanisms as critical for editing the epigenetic profile of the early embryo.

TL;DR: In this article, the authors investigated oxygen consumption of equine sperm mitochondria during incubation in four commercially available sperm cryopreservation extenders: modified INRA 96, BotuCrio, EZ Freezin, and MFR5.

TL;DR: Assessment of sperm functional characteristics in the frozen-thawed semen of buffalo bulls and their relationship with field fertility revealed high positive correlation with buffalo bull fertility (adjusted R2 = 0.73, C[p] =Â0.80).

TL;DR: This review is focused on genetic considerations for bull selection, physiology of reproductive development, breeding soundness evaluation, recent advances in assessing frozen semen, and existing and emerging uses of sexed semen in beef cattle production.

TL;DR: Assessment of CASA parameters and some other sperm structural and functional parameters, that is, integrity of plasma membrane and acrosome, and transmembrane potential of mitochondria were able to predict the in vivo fertility of water buffalo bull during low-breeding season.

TL;DR: The results showed that Porphyromonadaceae, Fusobacteriaceae, Leptotrichi Families, and Mycoplasmataceae may be associated with uterine disease and illustrate the importance of including endometrial biopsies to obtain more detailed knowledge of the pp uterine microbiota.

TL;DR: Although melatonin during IVM in a defined medium does not stimulate nuclear maturation progression it does stimulate meiosis resumption and such treated oocytes support subsequent embryo development.