Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care This report synthesizes evidence about innate hormonally-mediated physiologic processes in women and fetuses/newborns during childbearing, and possible impacts of common maternity care practices and interventions on these processes, focusing on four hormone systems that are consequential for childbearing. Core hormonal physiology principles reveal profound interconnections between mothers and babies, among hormone systems, and from pregnancy through to the postpartum and newborn periods. Overall, consistent and coherent evidence from physiologic understandings and human and animal studies finds that the innate hormonal physiology of childbearing has significant benefits for mothers and babies. Such hormonally-mediated benefits may extend into the future through optimization of breastfeeding and maternal-infant attachment. A growing body of research finds that common maternity care interventions may disturb hormonal processes, reduce their benefits, and create new challenges. Developmental and epigenetic effects are biologically plausible but poorly studied. The perspective of hormonal physiology adds new considerations for benefit-harm assessments in maternity care, and suggests new research priorities, including consistently measuring crucial hormonally-mediated outcomes that are frequently overlooked. Current understanding suggests that safely avoiding unneeded maternity care interventions would be wise, as supported by the Precautionary Principle. Promoting, supporting, and protecting physiologic childbearing, as far as safely possible in each situation, is a low-technology health and wellness approach to the care of childbearing women and their fetuses/newborns that is applicable in almost all maternity care settings. i CHILDBIRTH CONNECTION | HORMONAL PHYSIOLOGY OF CHILDBEARING | ABSTRACT

/pdf/hormonal-physiology-of-childbearing-evidence-and-4qcycdtfzr.pdf

Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care

Cryopreservation of semen and artificial insemination have an important, positive impact on cattle production, and product quality. Through the use of cryopreserved semen and artificial insemination, sperm from the best breeding bulls can be used to inseminate thousands of cows around the world. Although cryopreservation of bull sperm has advanced beyond that of other species, there are still major gaps in the knowledge and technology bases. Post-thaw viability of sperm is still low and differs significantly among the breeding bulls. These weaknesses are important because they are preventing advances both in fundamental science of mammalian gametes and reproductive biotechnology. Various extenders have been developed and supplemented with chemicals to reduce cryodamage or oxidative stress with varying levels of success. More detailed insights on sperm morphology and function have been uncovered through application of advanced tools in modern molecular and cell biology. This article provides a concise review of progress in the cryopreservation of bull sperm, advances in extender development, and frontiers using diverse techniques of the study of sperm viability. This scientific resource is important in animal biotechnology because with the advances in discovery of sperm fertility markers, there is an urgent need to improve post-thaw viability and fertility of sperm through enhanced cryopreservation for precision agriculture to produce food animals to ensure food security on the global scale.

/pdf/advances-in-cryopreservation-of-bull-sperm-1wzbixqyd1.pdf

Advances in cryopreservation of bull sperm

Sperm cryopreservation represents a powerful tool for livestock breeding. Several efforts have been made to improve the efficiency of sperm cryopreservation in different ruminant species. However, a significant amount of sperm still suffers considerable cryodamage, which may affect sperm quality and fertility. Recently, the use of different "omics" technologies in sperm cryobiology, especially proteomics studies, has led to a better understanding of the molecular modifications induced by sperm cryopreservation, facilitating the identification of different freezability biomarkers and certain proteins that can be added before cryopreservation to enhance sperm cryosurvival. This review provides an updated overview of the molecular mechanisms involved in sperm cryodamage, which are in part responsible for the structural, functional and fertility changes observed in frozen-thawed ruminant sperm. Moreover, the molecular basis of those factors that can affect the sperm freezing resilience of different ruminant species is also discussed as well as the molecular aspects of those novel strategies that have been developed to reduce sperm cryodamage, including new cryoprotectants, antioxidants, proteins, nanoparticles and vitrification.

/pdf/sperm-cryodamage-in-ruminants-understanding-the-molecular-20y2f2ydu2.pdf

Sperm Cryodamage in Ruminants: Understanding the Molecular Changes Induced by the Cryopreservation Process to Optimize Sperm Quality

Early stages of mammalian embryonic development are now known to be very sensitive to their microenvironment, with long term effects on fetal, postnatal, and adult health, thus extending to these early stages the concept of Developmental Origin of Health and Disease (DoHaD). In this scientific context, and with 3% of births in developed countries, safety of Assisted Reproductive Techniques procedures becomes a matter of concern. Besides, embryo technologies in domestic mammals, using huge number of embryos, do not seem to evidence heavy impacts on adult phenotypes. This paper first discusses what can or cannot be concluded from farm animal data, then develops long term effects of ART procedures (ovarian stimulation, in vitro fertilization and embryo culture) evidenced in model species (mainly mouse model). Recent literature demonstrates both individual and cumulative effects of each ART procedure on fetal and postnatal phenotypes. In a second part, because they are sources for further perturbations, immediate effects of ART on early embryo phenotypes at the cellular and molecular levels are described in both farm animals and model species. Mechanistic hypotheses supporting these ART induced phenotypic alterations are subsequently considered. Finally, taking into account interspecies differences in the mechanisms likely to be involved, the relevance of results obtained in animal models for human ART are discussed.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/mrd.22970

Long term effects of ART: What do animals tell us?

'Four Seasons' in an animal rescue centre; classical music reduces environmental stress in kennelled dogs.

Although some information exists on the stress response of horses in equestrian sports, the horse-rider team is much less well understood. In this study, salivary cortisol concentrations, heart rate (HR) and heart rate variability (HRV), SDRR (standard deviation of beat-to-beat interval) and RMSSD (root mean square of successive beat-to-beat intervals) were analysed in horses and their riders (n=6 each) at a public performance and an identical rehearsal that was not open to the public. Cortisol concentrations increased in both horses and riders (P<0.001) but did not differ between performance and rehearsal. HR in horses and riders increased during the rehearsal and the public performance (P<0.001) but the increase in HR was more pronounced (P<0.01) in riders than in their horses during the public performance (from 91 ± 10 to 150 ± 15 beats/min) compared to the rehearsal (from 94 ± 10 to 118 ± 12 beats/min). The SDRR decreased significantly during the equestrian tasks in riders (P<0.001), but not in their horses. The RMSSD decreased in horses and riders (P<0.001) during rehearsal and performance, indicating a decrease in parasympathetic tone. The decrease in RMSSD in the riders was more pronounced (P<0.05) during the performance (from 32.6 ± 6.6 to 3.8 ± 0.3 ms) than during the rehearsal (from 27.5 ± 4.2 to 6.6 ± 0.6 ms). The study has shown that the presence of spectators caused more pronounced changes in cardiac activity in the riders than it did in their horses.

Cortisol release, heart rate and heart rate variability in the horse and its rider: Different responses to training and performance

Effects of season, age, sex, and housing on salivary cortisol concentrations in horses

Heart rate (HR) and heart rate variability (HRV) are often determined with Polar heart rate monitors (HRMs; S810i; Polar, Kempele, Finland). The aims of this study were to compare data from horses obtained by Polar HRMs and a portable Televet electrocardiogram (ECG; 100 version 4.2.3; Kruuse, Marslev, Denmark) device and to determine appropriate recording times in horses (n=14). Correlations were calculated and a Bland-Altman analysis was carried out to examine agreement between recording systems. For beat-to-beat (RR) interval, uncorrected and corrected data were highly correlated irrespective of the recording system and recording time ( r >0.99, P P r >0.9, P

Comparison of heart rate and heart rate variability obtained by heart rate monitors and simultaneously recorded electrocardiogram signals in nonexercising horses

Cytosine methylation of sperm DNA in horse semen after cryopreservation.

Equestrian sports require the co-operation of two species, horses and humans, but it is unknown to what extent stress responses in the rider affect the horse. In this study, the stress response of experienced and less-experienced horses and riders at showjumping was analysed. Sixteen sport horses were divided into two groups (n = 8 each) by experience and were ridden by highly experienced professionals (n = 8) and less-experienced riders (n = 8). Riders jumped a course of obstacles with an experienced and a less-experienced horse and horses took part with an experienced and less-experienced rider. Salivary cortisol, heart rate and heart-rate variability (HRV) variables, standard deviation of RR interval (SDRR) and root mean square of successive RR differences (RMSSD) were analysed. Cortisol and heart rate increased and HRV decreased in all riders and horses. In less-experienced riders, cortisol release was higher on a lessexperienced versus an experienced horse but the horses’ cortisol release was not affected by experience of their riders. Heart rate did not differ between groups of horses and was not affected by experience of the rider but was higher in less-experienced versus experienced riders. The HRV decreased in horses and riders and SDRR was lower in less-experienced versus experienced riders. Thus, lower experience of riders appears not to affect physiological stress parameters in their horses during a showjumping course.

/pdf/effects-of-the-level-of-experience-of-horses-and-their-3d3v8c6wks.pdf

Natascha Ille

Papers

Cortisol release, heart rate and heart rate variability in the horse and its rider: Different responses to training and performance

Effects of season, age, sex, and housing on salivary cortisol concentrations in horses

Comparison of heart rate and heart rate variability obtained by heart rate monitors and simultaneously recorded electrocardiogram signals in nonexercising horses

Cytosine methylation of sperm DNA in horse semen after cryopreservation.

Effects of the level of experience of horses and their riders on cortisol release, heart rate and heart-rate variability during a jumping course