Effect of Mitoquinone on sperm quality of cryopreserved stallion semen.

This study aimed to investigate the effect of mitochondria-targeted antioxidants (Mitoquinone, MitoQ) on the quality of frozen-thawed stallion semen. Semen samples collected from three fertile stallions aged 10 - 13 years, were filtered, centrifuged in a skimmed milk-based extender, and diluted to a final concentration of 50 × 106 sperm/mL in freezing medium. Diluted semen was divided into five experimental groups supplemented with MitoQ at concentrations of 0 (control), 25, 50, 100, and 200 nM and then subjected to freezing after cooling and equilibration.

In vitro effects of different ozone preparations on microorganisms responsible for endometritis in the mare.

Infectious endometritis is considered one of the major causes of infertility and it can affect up to 60% of barren mares. It is characterized by the presence of one or more microorganisms in the reproductive tract and it is treated with the administration of antibiotics, ecbolic agents and uterine lavages. Ozone, thanks to its antimicrobial properties that are based on its high oxidative potential, could represent an effective alternative treatment for endometritis.

Single-Step Genomic Prediction of Superovulatory Response Traits in Japanese Black Donor Cows.

We assessed the performance of single-step genomic prediction of breeding values for superovulatory response traits in Japanese Black donor cows. A total of 25,332 records of the total number of embryos and oocytes (TNE) and the number of good embryos (NGE) per flush for 1874 Japanese Black donor cows were collected during 2008 and 2022. Genotype information on 36,426 autosomal single-nucleotide polymorphisms (SNPs) for 575 out of the 1,874 cows was used.

Comparing Methods to Select Candidates for Re-Genotyping to Impute Higher-Density Genotype Data in a Japanese Black Cattle Population: A Case Study.

As optimization methods to identify the best animals for dense genotyping to construct a reference population for genotype imputation, the MCA and MCG methods, which use the pedigree-based additive genetic relationship matrix ( matrix) and the genomic relationship matrix ( matrix), respectively, have been proposed. We assessed the performance of MCA and MCG methods using 575 Japanese Black cows. Pedigree data were provided to trace back up to five generations to construct the matrix with changing the pedigree depth from 1 to 5 (five MCA methods).

Bayesian estimation of genetic parameters for superovulatory response traits in Japanese Black donor cows using count data models.

We estimated genetic parameters for two in vivo embryo production-related superovulatory response traits-total number of embryos and oocytes (TNE) and number of good embryos (NGE)-in Japanese Black donor cows through Bayesian count regression analysis. We used 20,257 records of superovulation treatments from 1546 Japanese Black cows, with 1102 (5.4%) zero-count records for TNE and 3533 (17.

Genetic relationship between superovulatory response traits and carcass traits in Japanese Black cattle.

We estimated the genetic correlations between superovulatory response traits and carcass traits in Japanese Black cattle. As regards the superovulatory response traits in cows, we analyzed the phenotypic records of the total number of embryos and oocytes (TNE) and the number of good embryos (NGE) collected from 1532 donors between 2008 and 2018. As regards the carcass traits in fattened animals, we analyzed the phenotypic records for cold carcass weight, rib eye area, rib thickness, subcutaneous fat thickness, estimated yield percent, and marbling score for 1448 progenies derived from 596 donors and slaughtered between 2004 and 2020.

Characterization of Serum Metabolome and Proteome Profiles Identifies SNX5 Specific for Pregnancy Failure in Holstein Heifers.

Pregnancy loss predominantly occurs during the first 3-4 weeks due to fertilization failure or early embryonic losses in cattle. Insufficient biochemical communication between conceptus (embryo plus extraembryonic membranes) and endometrium has been suspected as the primary cause for early embryonic losses. If molecules regulating this communication were identified, molecular mechanisms associated with early pregnancy losses could be better understood.

Exploring the size of reference population for expected accuracy of genomic prediction using simulated and real data in Japanese Black cattle.

Background: Size of reference population is a crucial factor affecting the accuracy of prediction of the genomic estimated breeding value (GEBV). There are few studies in beef cattle that have compared accuracies achieved using real data to that achieved with simulated data and deterministic predictions. Thus, extent to which traits of interest affect accuracy of genomic prediction in Japanese Black cattle remains obscure.

Estimation of genetic parameters for superovulatory response traits in Japanese Black cows.

The aim of this study was to estimate genetic parameters for superovulatory response traits in order to explore the possibility of genetic improvement in Japanese Black cows. We analyzed 19 155 records of the total number of embryos and oocytes (TNE) and the number of good embryos (NGE) collected from 1532 donor cows between 2008 and 2018. A two-trait repeatability animal model analysis was performed for both.

Fertility risk factors in transferring Japanese Black embryos into dairy heifers: An epidemiological study.

The aims of this study were 1) to summarize the current status of Japanese Black (JB) embryo transfer into Holstein heifers, which is carried out on a commercial basis in Japan, and 2) to reveal fertility risk factors, including those from the environment (year and season of transfer), recipient (age, number of transfers, clinical status of the ovaries) and embryo (quality, stage, state, genetic background). We used data from 4467 JB fresh or frozen embryo transfers into Holstein heifers conducted by Zen-noh Embryo Transfer Center during 2016-2018, and the differences in fertility risk due to factors related to the environment, recipient, and embryo were statistically evaluated. Differences in fertility risk due to each variable were observed, leading to significant differences in fertility with respect to year of transfer, embryo quality, embryo state, and embryo breed.

Glutathione ethyl ester improved the age-induced decline in the developmental competence of bovine oocytes.

The aberrant redox regulation and anti-oxidative defense is one of the main causes of age-induced decline in oocytes quality and embryo development in mammals. The present study aimed to elucidate the effect of glutathione ethyl ester (GSH-OEt), a cell-permeable glutathione (GSH) donor, on the developmental competence of oocytes in cows with advanced reproductive age. Oocytes were collected from cows aged 30-50 months or >120 months, which were defined as young or aged, respectively, and subjected to in vitro maturation (IVM) in the presence of 5 mM of GSH-OEt.

Developmental kinetics and viability of bovine embryos produced in vitro with sex-sorted semen.

The present study aimed to elucidate the developmental kinetics, growth potential, and viability of bovine embryos produced in vitro with sexed semen. Bovine oocytes were fertilized in vitro using unsorted and X-sorted semen from the same Holstein bulls, and the kinetics of in vitro development were continuously monitored for 10 d through time-lapse cinematography. The blastocyst formation rate was lower in the X-sorted group than in the unsorted group (P < 0.

The association between detection of Mycobacterium avium subsp. paratuberculosis DNA in feces and histopathological classification.

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease (JD), a chronic infectious disease that causes intractable diarrhea in ruminants. To control the occurrence of JD in cattle, a national surveillance is conducted in Japan.

IFNT-independent effects of intrauterine extracellular vesicles (EVs) in cattle.

Extracellular vesicles (EVs) present in uterine lumen are involved in conceptus-endometrial interactions during the pre-implantation period. Despite numerous studies conducted on interferon tau (IFNT), a major protein of maternal recognition of pregnancy, the effect of intrauterine EVs on the endometrium during pre-implantation periods has not been well-characterized. To characterize conceptus-derived intrauterine EVs independent of IFNT, transcripts found from RNA-seq analysis in RNAs extracted from primary bovine endometrial epithelial cells (EECs) treated with cyclic day 17 (C17) EVs, pregnant day 17 (P17) EVs or IFNT were analyzed.

Effects of miR-98 in intrauterine extracellular vesicles on maternal immune regulation during the peri-implantation period in cattle.

Evidence accumulated suggests that extracellular vesicles (EVs) present in uterine lumen play a role in conceptus-endometrial cell interactions during peri-implantation periods. However, how intrauterine EVs function on endometrium have not been well characterized. To study how intrauterine EVs affect endometrial milieu in cattle, bovine endometrial epithelial cells (EECs) were treated with EVs isolated from uterine flushing fluids (UFs) on day 17 or 20 pregnancy (P17, P20, respectively; conceptus implantation to endometrium begins on days 19-19.

Time of first polar body extrusion affects the developmental competence of equine oocytes after intracytoplasmic sperm injection.

Assisted reproduction techniques (ARTs) have become widespread in the equine breeding industry. In particular, the combination of oocyte recovery from live mares followed by IVM and intracytoplasmic sperm injection (ICSI) has increased markedly among the ARTs used with valuable or low-fertility animals. There is currently no consensus among research groups regarding the optimal oocyte maturation period to produce high-quality embryos.

Growth potential of bovine embryos presenting abnormal cleavage observed through time lapse cinematography.

Time-lapse monitoring (TLM) has emerged as a novel technology for the continuous and noninvasive evaluation of embryos. TLM has revealed the prevalence of specific dysmorphisms such as abnormal development during the early-cleavage stage of embryos. However, little information is available on the prevalence and consequences of abnormal cleavage in bovine embryos.

Effect of environmental factors and changes in the body condition score on the onset of the breeding season in mares.

Several methods have been proposed to advance the onset of the breeding season in horses. Most of them are based on the exposure to an artificial lighting period combined with hormonal treatments. Mares exposed to an artificial photoperiod are most often housed indoors where the ambient temperature is often higher than the outside temperature.

Correlations between mitochondrial respiration activity and residual feed intake after divergent genetic selection for high- and low- oxygen consumption in mice.

The aims of the present study were to identify the differences between two mouse lines (high (H)- and low (L)-oxygen consumption) in terms of mitochondrial respiratory activity when GMP (glutamate, malate, and pyruvate) and succinic acid are used as substrates and to examine the relationship between mitochondrial respiration activity and feed efficiency in both lines. The average daily feed intake, feed conversion ratio (FCR), and residual feed intake (RFI) were significantly higher in the H than the L line. The correlation between FCR and RFI was significant (r = 0.

Application of intracytoplasmic sperm injection to the embryo production in aged cows.

Reduction in oocyte quality is a major factor responsible for declining fertility associated with maternal aging in cows. The objective of the present study was to determine whether intracytoplasmic sperm injection (ICSI) could increase the efficiency of embryo production in older cows. We used cows aged 30 to 50 months or >120 months, which were defined as young or aged, respectively.

Effect of a single epidural administration of follicle-stimulating hormone via caudal vertebrae on superstimulation for in vivo and in vitro embryo production in Japanese black cows.

Here, we describe a simplified procedure for embryo production in the Japanese black cow that uses a single caudal epidural injection of follicle-stimulating hormone (FSH). First, we compared the efficiency of superovulation for in vivo embryo production between conventional multiple FSH treatment (control, n = 10) and single epidural administration (epidural, n = 5). The number of transferable blastocysts was similar between control and epidural groups (4.

Down-regulation of transcription factor OVOL2 contributes to epithelial-mesenchymal transition in a noninvasive type of trophoblast implantation to the maternal endometrium.

Embryo implantation into the uterine endometrium is required for pregnancy establishment in most mammals. By using global expression analysis, we investigated the molecules that are related to epithelial-mesenchymal transition (EMT) in noninvasive bovine trophoblasts and found that the transcription factor, ovo-like zinc finger 2 ( OVOL2), which is essential for mesenchymal-epithelial transition in various cancers, was down-regulated after trophoblast attachment to the endometrial epithelium in utero. In cultured bovine trophoblast cells, OVOL2 down-regulation occurred only when cells were allowed to attach to bovine endometrial epithelial cells via the TEAD3/YAP signaling pathway.

Tim-3 signaling in peripheral NK cells promotes maternal-fetal immune tolerance and alleviates pregnancy loss.

Pregnancy loss occurs in about 15% of clinically recognized pregnancies, and defective maternal-fetal immune tolerance contributes to more than 50% of these events. We found that signaling by the type I membrane protein T cell immunoglobulin and mucin-containing protein 3 (Tim-3) in natural killer (NK) cells had an essential protective role during early pregnancy. Tim-3 on peripheral NK (pNK) cells was transiently increased in abundance during the first trimester of pregnancy, which depended on interleukin-4 (IL-4)-signal transducer and activator of transcription 6 (STAT6) and progesterone signaling.

Novel endogenous retrovirus-derived transcript expressed in the bovine placenta is regulated by WNT signaling.

Endogenous retroviruses (ERVs) are involved in placentation; perhaps, the most well-known s are the syncytins, actively transcribed genes involved in cell-cell fusion and possible morphological variations. However, ERVs other than syncytins that play an important role in placental development have not been well characterized. To identify genes expressed during the onset of placentation in the bovine species, we characterized the expression profiles of bovine conceptus transcripts during the peri-attachment period using RNA-seq analysis, and confirming some candidates through real-time PCR.