The Imitation of the Ovarian Fatty Acid Profile of Superfertile Dummerstorf Mouse Lines during IVM of Control Line Oocytes Could Influence Their Maturation Rates.

Declining human fertility worldwide is an attractive research target for the search for "high fertility" genes and pathways to counteract this problem. To study these genes and pathways for high fertility, the superfertile Dummerstorf mouse lines FL1 and FL2 are two unique model organisms representing an improved fertility phenotype. A direct reason for this remarkable characteristic of increased litter size, which reaches >20 pups/litter in both FLs, is the raised ovulation rate by approximately 100%, representing an impressive record in this field.

Alterations in gonadotropin, apoptotic and metabolic pathways in granulosa cells warrant superior fertility of the Dummerstorf high fertility mouse line 1.

The development and maturation of ovarian follicles is a complex and highly regulated process, which is essential for successful ovulation. During recent decades, several mouse models provided insights into the regulation of folliculogenesis. In contrast to the commonly used transgenic or knockout mouse models, the Dummerstorf high-fertility mouse line 1 (FL1) is a worldwide unique selection experiment for increased female reproductive performance and extraordinary high fertility.

Lower Plasmatic Levels of Saturated Fatty Acids and a Characteristic Fatty Acid Composition in the Ovary Could Contribute to the High-Fertility Phenotype in Dummerstorf Superfertile Mice.

In recent decades, fertility traits in humans as well as in farm animals have decreased worldwide. As such, it is imperative to know more about the genetics and physiology of increased or high fertility. However, most of the current animal models with reproductive phenotypes describe lower fertility or even infertility (around 99%).

Higher quality rather than superior quantity of oocytes determine the amount of fertilizable oocytes in two outbred Dummerstorf high-fertility mouse lines.

Dummerstorf fertility lines FL1 and FL2 represent two models of enhanced fertility characterized by the doubling of the litter size compared with an unselected control population (ctrl line, Dummerstorf FztDU). Both biodiverse FLs managed to reach this goal by increasing the ovulation rate per cycle, even showing decreased pregnancy rate and irregular oestrous cycle and metabolic hormone levels, compared with ctrl. The aim of the present study was to analyse oocytes in terms of quality and quantity by comparing the entire pool of oocytes per ovary, with those from the antral follicles within the same animal.

Effects of different cyclooxygenase inhibitors on prostaglandin E production, steroidogenesis and ovulation of bovine preovulatory follicles.

Ovulation is an inflammation-like process, and cyclooxygenase-2 (COX-2)-dependent production of prostaglandin E (PGE) is its key mediator. Balanced regulation of inflammatory processes in high-yielding dairy cows may be essential for physiological ovulation and fertility. This study aimed to elucidate the mechanisms underlying ovulation failure and cyst development after disturbing intrafollicular inflammatory cascades.

Endocrine and molecular factors of increased female reproductive performance in the Dummerstorf high-fertility mouse line FL1.

The Dummerstorf high-fertility mouse line FL1 is a worldwide unique selection experiment for increased female reproductive performance. After more than 190 generations of selection, these mice doubled the amount of offspring per litter compared to the unselected control line. FL1 females have a superior lifetime fecundity and the highest Silver fecundity index that has been described in mice, while their offspring show no signs of growth retardation.

Genomic characterization of the world's longest selection experiment in mouse reveals the complexity of polygenic traits.

Background: Long-term selection experiments are a powerful tool to understand the genetic background of complex traits. The longest of such experiments has been conducted in the Research Institute for Farm Animal Biology (FBN), generating extreme mouse lines with increased fertility, body mass, protein mass and endurance. For >140 generations, these lines have been maintained alongside an unselected control line, representing a valuable resource for understanding the genetic basis of polygenic traits.

Altered insulin, leptin and ghrelin hormone levels and atypical estrous cycle lengths in two highly fertile mouse lines.

Mouse models of decreased fertility mainly support scientific knowledge in the field of reproductive biology. In this study, we changed the perspective, using Dummerstorf high-fertility mouse lines FL1 and FL2 selected for increased reproductive performances that doubled the amount of ovulated oocytes per cycle and the number of offspring per litter compared to an unselected control line (founder population, FZTDU, ctrl). After recent observations, both fertility lines seem to show a lower pregnancy rate compared to ctrl together with an atypical reproductive cycle.

Two mouse lines selected for large litter size display different lifetime fecundities.

We recently described two outbred mouse lines that were selected for large litter size at first delivery. However, lifetime fecundity appears to be economically more important for the husbandry of many polytocous species for which mouse lines might serve as bona fide animal models (e.g.

Altered testicular cell type composition in males of two outbred mouse lines selected for high fertility.

Background: Recently we described two outbred mouse lines which have been selected for high fertility. These mouse models doubled the number of offspring per litter.

Objectives: Although selected for a primarily female-trait of high fertility (increased litter size), we were interested whether also males of the fertility lines show differences within their reproductive organs.

Induction of cystic ovarian follicles (COFs) in cattle by using an intrafollicular injection of indomethacin.

The aim of this study was to establish a model to induce cystic ovarian follicles (COFs) in cattle using the cyclooxygenase inhibitor, indomethacin. Eighteen Holstein-Frisian cattle were synchronized with prostaglandin F2alpha (PGF2α) and gonadotropin-releasing hormone (GnRH). Ultrasound-guided transvaginal intrafollicular injections were performed in 23 preovulatory follicles with different concentrations of indomethacin 16 h after GnRH administration.

Testicular transcriptional signatures associated with high fertility.

Factors of high fertility are poorly described. The majority of transgenic or knockout models with a reproductive phenotype are subfertile or infertile phenotypes. Few genotypes have been linked to improved reproductive performance (0.

Selection for female traits of high fertility affects male reproductive performance and alters the testicular transcriptional profile.

Background: Many genes important for reproductive performance are shared by both sexes. However, fecundity indices are primarily based on female parameters such as litter size. We examined a fertility mouse line (FL2), which has a considerably increased number of offspring and a total litter weight of 180% compared to a randomly bred control line (Ctrl) after more than 170 generations of breeding.

Hepatic thyroid signaling of heat-stressed late pregnant and early lactating cows.

During the transition between late gestation and early lactation, dairy cows experience severe metabolic stress due to the high energy and nutrient requirements of the fetus and the mammary gland. Additional thermal stress that occurs with rising temperatures during the ongoing climate change has further adverse implications on energy intake, metabolism and welfare. The thyroid hormone (TH)-mediated cellular signaling has a pivotal role in regulation of body temperature, energy intake and metabolic adaptation to heat.

Reproductive performance primarily depends on the female genotype in a two-factorial breeding experiment using high-fertility mouse lines.

Mouse models showing an improved fertility phenotype are barely described in the literature. In the present study, we further characterized two outbred mouse models that have been selected for the phenotype 'high fertility' for more than 177 generations (fertility lines (FL) 1 and 2). In order to delineate the impact of males and females on fertility parameters, we performed a two-factorial breeding experiment by mating males and females of the three different genotypes (FL1, FL2, unselected control (Ctrl)) in all 9 possible combinations.

Impaired Repressor Function in SUMOylation-Defective Thyroid Hormone Receptor Isoforms.

Background: Many nuclear receptors are modified by posttranslational modifications.

Objectives: The transcriptional activity of thyroid hormone receptors (TRs) is modified by the influence of its ligand (thyroid hormones T and T), but is also affected by posttranslational modifications. This study focuses on the SUMOylation of TR isoforms and the consequences on transcriptional activity and promoter occupancy.

Effects of rutin and buckwheat seeds on energy metabolism and methane production in dairy cows.

Flavonoids are secondary plant metabolites with several health promoting effects. As dairy cows often suffer from metabolic imbalance and health problems, interest is growing in health improvements by plant substances such as flavonoids. Our group has recently shown that the flavonoids quercetin and rutin (a glucorhamnoside of quercetin) are bioavailable in cows when given via a duodenal fistula or orally, respectively, affect glucose metabolism, and have beneficial effects on liver health.

Quercetin Feeding in Newborn Dairy Calves Cannot Compensate Colostrum Deprivation: Study on Metabolic, Antioxidative and Inflammatory Traits.

Immaturity of the neonatal immune system is causative for high morbidity in calves and colostrum intake is crucial for acquiring passive immunity. Pathogenesis is promoted by reactive oxygen species accumulating at birth if counter-regulation is inadequate. The flavonol quercetin exerts antioxidative and anti-inflammatory effects that may enhance neonatal health.

The Effects of Oral Quercetin Supplementation on Splanchnic Glucose Metabolism in 1-Week-Old Calves Depend on Diet after Birth.

Background: Inadequate colostrum supply results in insufficient intake of macronutrients and bioactive factors, thereby impairing gastrointestinal development and the maturation of glucose metabolism in neonatal calves. The flavonoid quercetin has been shown to have health-promoting properties, including effects in diabetic animals. However, quercetin interacts with intestinal glucose absorption and might therefore exert negative effects in neonates.

Effects of a 6-wk intraduodenal supplementation with quercetin on energy metabolism and indicators of liver damage in periparturient dairy cows.

Periparturient dairy cows experience metabolic challenges that result in a negative energy balance (EB) and a range of postpartum health problems. To compensate for the negative EB, cows mobilize fatty acids from adipose tissues, which can lead to fatty liver disease, a periparturient metabolic disorder. Flavonoids, such as quercetin (Q), are polyphenolic substances found in all higher plants and have hepatoprotective potential and the ability to prevent or reduce lipid accumulation in the liver.

Prostaglandin E synthase interacts with inducible heat shock protein 70 after heat stress in bovine primary dermal fibroblast cells.

Exposure to heat stress in dairy cows leads to undesired side effects that are reflected by complex alterations in endocrine parameters, such as reduced progesterone, estradiol, and thyroid hormone concentrations. These endocrine maladaptation leads to failure to resume cyclicity, a poor uterine environment and inappropriate immune responses in postpartum dairy cows. Prostaglandins (PG's) are lipid mediators, which serve as signal molecules in response to various external stimuli as well as to cell-specific internal signal molecules.

In vivo microinjection and electroporation of mouse testis.

This video and article contribution gives a comprehensive description of microinjection and electroporation of mouse testis in vivo. This particular transfection technique for testicular mouse cells allows the study of unique processes in spermatogenesis. The following protocol focuses on transfection of testicular mouse cells with plasmid constructs.

Low and high dietary protein:carbohydrate ratios during pregnancy affect materno-fetal glucose metabolism in pigs.

Inadequate dietary protein during pregnancy causes intrauterine growth retardation. Whether this is related to altered maternal and fetal glucose metabolism was examined in pregnant sows comparing a high-protein:low-carbohydrate diet (HP-LC; 30% protein, 39% carbohydrates) with a moderately low-protein:high-carbohydrate diet (LP-HC; 6.5% protein, 68% carbohydrates) and the isoenergetic standard diet (ST; 12.