Is sperm DNA fragmentation (SDF) involved in the lower fertilising ability of cryopreserved spermatozoa from cancer patients? In this study we evaluated SDF in two different cytometric sperm populations (PI^brighter and PI^dimmer). In cryopreserved spermatozoa from cancer patients, PI^brighter SDF, which is more relevant to reproduction, was positively related to sperm motility and that the proportion of these cells was higher in samples from cancer versus non-cancer (oligozoospermic or affected by autoimmune pathologies) patients. The results of the study indicate that thawed motile spermatozoa of cancer patients may carry DNA damage.

The reasons why somatic cell nuclear transfer (SCNT) pregnancies are at increased risk of pregnancy loss are poorly understood. This study investigated pregnancy losses and gene expression of inflammatory mediators in sheep and goat SCNT pregnancies. Sheep SCNT pregnancies had an increased incidence of pregnancy loss and increased expression of inflammatory cytokines in the placenta, which indicates the presence of an unfavourable environment for fetal development.

This study examined the metabolite profile of serum and follicular fluid on Day 7 of the oestrous cycle in Holstein cows with good or poor genetic merit for fertility. Differences between the two genotypes in the abundance of fatty acids and amino acids were highly predictive of fertility. The results demonstrate that metabolite profiles in cattle respond to genetic selection for fertility traits, and specific metabolites may be useful biomarkers for fertility

Insulin resistance (IR) is an underlying factor, common to both polycystic ovary syndrome (PCOS) and type 2 diabetes. Genetic factors have also been reported to play a role in the pathogenesis of these two conditions, indicting a common genetic aetiology. In this study we aim to determine whether the genetic association between IR and diabetogenic SNPs is affected by PCOS status in Iranian women and found that the association may be influenced by the condition.

The effect of cumulus cell-conditioned medium (CCM) on the differentiation of buffalo embryonic stem cells to germ cells were explored. A concentration of 20%–40% conditioned medium induced the highest expression of primordial germ cell, meiotic, spermatocyte and oocyte markers and led to the formation of oocyte-like structures. Further development of the cumulus conditioned medium induced differentiation strategy would be useful for understanding mammalian gametogenesis and transgenic animal production.

Infertility affects 1 in 10 couples or millions of people worldwide and while IVF is an important intervention, 75% of all embryos transferred into the uterus do not establish a pregnancy. We investigated how the uterus of infertile women may prevent pregnancy and discovered a protein released by uterine tissue that potentially blocks pregnancy. Targeting this protein may be useful as a new treatment option for infertile women.

The aquaporin family plays a fundamental role in water and solute transport across biological membranes. The present work has studied, for the first time, the presence and localisation of aquaglyceroporin 3 in boar spermatozoa. Although two different localisation patterns for this protein were identified, neither AQP3 content nor its localisation were found to be correlated with sperm quality parameters.

We studied for the first time the effect of high inbreeding levels in cattle sperm by automatised and objective methods. An extensive genetic analysis using an animal model showed that inbred bulls have a reduced field fertility and an increased calving interval compared with non-inbred bulls. Sperm from high inbred animals showed an increased ‘hyper-active like’ movement that could explain their decreased fertility.

Mammalian eggs are often affected by aneuploidy, leading to failure in embryo implantation, miscarriages and genetic diseases. In horse oocytes the onset of aneuploidy is correlated with the disruption of an epigenetic mark that occurs without changes in gene expression. A deeper knowledge of the molecular basis of aneuploidy will allow the development of safer treatments to obtain healthy eggs.

To determine whether body weight has an effect on semen quality, the present study explored the possible association between body weight (in terms of body mass index) and sperm function. The results indicate that both morbid obesity and being underweight have a negative effect on sperm quality, probably as a result of changes to epididymal function. These findings highlight the importance of an adequate body weight as the best option for fertility.

The function of epigenetic marks present in retained histones of mature spermatozoa is largely unknown. By reducing the methylation level at lysines 4 and 9 of histone 3 of mature spermatozoa we aimed to shed light on their significance during development. We discovered that these marks are important for normal embryo development and their reduction leads to abortions, premature death and morphological abnormalities in the offspring.

The average age for a primipara has been increased and maternal age affects the quality of oocytes. The present study addressed whether age-associated deterioration of oocytes stems from the oocyte itself or the surrounding environment and found that follicular fluid plays a major role. On the basis of the results, given optimum conditions, oocytes derived from aged females could give rise to high-quality oocytes.

Follicular growth is mediated by gonadotropic hormones, growth factors and signalling pathways, such as the mammalian target of rapamycin (mTOR) signalling pathway. However, the molecular mechanisms underlying the development of theca cells have rarely been studied. Herein we provide unbiased, detailed and convincing evidence (microarray, in vitro and in vivo studies) to demonstrate that mTOR/eukaryotic initiation factor 4F signalling plays an important role in follicular growth, particularly the development of thecal cells.

Lipids rafts are specialised membrane microdomains involved in cell signalling and phosphodiesterases are key enzymes involved in cyclic AMP signalling in the ovary. We found that in mural granulosa cell membranes, the cyclic AMP–phosphodiesterase activity is mainly contributed by the rafts. These results suggest that in mural granulosa cells, lipid rafts exist as a cell-signalling platform.

In female meiosis, accurate chromosome separation is driven by the spindle apparatus, which is organised under the regulation of unique microtubule organising centres (MTOCs). LIM kinase 1 activity is required for the establishment and maintenance of MTOC bipolarity in mouse oocytes during meiotic division. The results of the present study provide an insight into the molecular mechanism governing bipolar spindle formation in oocytes during meiotic maturation.

This study evaluated the effects of sperm motility enhancers, media and different IVF times on embryo development. The sperm motility enhancers caffeine and theophylline improved cleavage and embryo development rates, synthetic oviducal fluid fertilisation medium outperformed M199 fertilisation medium and shortening the oocyte–sperm coincubation time (from 18 to 8 h) resulted in similar overall embryo performance rates. This study provides important information for optimising IVF protocols.

Obesity, a global problem, adversely affects human health including reproduction. This study investigated whether exposure to an obesogenic environment during prenatal and postnatal periods affects the initiation and progress of spermatogenesis in rats. It is evident that an obese condition decreases counts of spermatids and spermatozoa and serum levels of testosterone and increases the proportion of abnormal spermatozoa, which might reduce reproductive potential.

In addition to oocyte Cd9 tetraspanin, Juno, a glycosylphosphatidylinositol (GIP)-anchored protein, has recently been discovered to be essential to mammalian fertilisation, as a sperm receptor for Izumo1. The present study demonstrates the involvement of another two other oocyte GPI-anchored proteins, namely growth arrest specific 1 (Gas1) and glial cell line-derived neurotrophic factor receptor α1 (Gfrα1), in fertilisation. The results reinforce the implication of several molecules forming probably complexes.

Monozygotic (MZ) twins are of great interest to elucidate the contributions of pre- and postnatal environmental factors on the expression of complex traits and diseases. In this study we investigated variations in sperm DNA methylation between MZ twin bulls to understand the observed differences in offspring productivity of MZ twin bulls despite their identical genetic backgrounds. Variation in sperm DNA methylation between MZ twin bulls was observed and may contribute to incongruous diverging performances of daughters sired by these bulls.