P–741 Fetal exposure to maternal perceived stress and male reproductive function in a cohort of young adults

Study question Is exposure to maternal perceived stress during pregnancy associated with reproductive function in adult male offspring? Summary answer While maternal perceived stress was prevalent in the first trimesters of pregnancy, our preliminary findings indicate little association with reproductive function in young men. What is known already Though studies in animals point to a connection between prenatal exposure to maternal stress and reproductive function in offspring, the underlying biological mechanisms generating a deficit remain largely unclear. In humans, the few available studies focus on exposure to bereavement or other relatively strong objective stressful life events. Our individual perception of stress is, however, more likely the sum of a complex process involving both the actual input, previous experiences, coping strategies and support from our surroundings. Study design, size, duration Young men and their mothers were identified through records from the Danish National Birth Cohort (DNBC). Information on exposure, i.e. maternal perceived life and emotional stress, was available from telephone interviews conducted at approximately 30 weeks of gestation (1996 to 2001). Recruitment of the young men lasted from 2017 to 2019 with 1058 participants enrolled in the final FEPOS cohort. Participants/materials, setting, methods Each of the 1058 men in the FEPOS cohort completed an online questionnaire and clinical examinations and provided a blood and semen sample. Information on potential pre- and postnatal confounders was retrieved from the DNBC, the Danish National Patient Register and the Danish Medical Birth Register. We applied negative binomial regression models to examine associations between maternal perceived life and emotional stress scores and semen quality, testicular size and reproductive hormones among the young men. Main results and the role of chance Among the 1052 young men included in preliminary analyses, the majority was exposed to maternal perceived life and/or emotional stress (76% and 83%, respectively) during the first trimesters. Life stress was predominantly related to the actual pregnancy (48%), maternal disease (19%) or occupational conditions (33%). Emotional stress included especially being touchy (58%), sad (38%) or tense (36%), covering aspects of both stress, depression and anxiety. Overall, results indicate little association between maternal stress scores and measures of semen quality and testicular size. Our study involves a large cohort with prospectively collected exposure data and direct measures of several male reproductive outcomes. We applied inverse probability weighting to account for selection into the FEPOS cohort and included a range of a priori selected maternal confounders in our models. Limitations, reasons for caution The male fetus may be particularly sensitive to exposure during the differentiation of reproductive tissues (8–14 weeks of gestation). Our self-reported measures of exposure cover the first 30 weeks of gestation. Absence of association may, thus, be due to a lack of specific information on timing of symptoms. Wider implications of the findings: While our preliminary findings may appear reassuring, further efforts to improve our understanding of maternal stress in relation to fetal health and potential consequences later in life are needed. Trial registration number Not applicable

TESTICULAR SIZE AND SPERM OUTPUT IN HOLSTEIN-FRIESIAN AND N'DAMA BULLS

Records collected over a period of four months from October 1978 to January 1979 from four Holstein-Friesian and four N'dama hulls, were used to study the relationship between testicular size and sperm output. Semen samples were collected from the bulls twice a week using the artificial vagina and non-oestrous female teasers. The means (± s.e.) of testicular measurements for Holstein-Friesian and N'danta, respectively, were 35.6 ± 1.8 and 7.9 ± 0.3cm. for scrotal cir­cumference, 12.6 ± 0.3 and 7.7 ± 0.8cm for testis length, 6.7 ± 0.3 and 3.7 ± 0.2em for testis diameter. Calculated mean testicular volumes were 296.8 I 22.2 and 57.4 ± 10.1m1 respectively for Holstein-Friesian and N'dama bulls. T-he mean total sperm per ejaculate were 8.80 t 3.045 x 109 for (be Holstein-Friesian and 3.03 ± 0.905 x 109 for the N'dama bulls. Simple correla­tions for Holstein-Friesian and N'damn in the same order, were between body weight and scrotal dr. rumference 0.49 and 0.66, body weight and sperm output/einculate 0.48 and 0.88, scrotal cir­cumference and testicular volume 0.74 and 0.60. scrotal circumference and sperm outpuilejactilete 0.18 and 0.69, and testicular volume and sperm out­put/ejaculate —.45 and 0.84. Regression equations for predicting sperm oat­put/ejaculate from testicular volume are given as Y = .13.458 — .031 X and Y' = - .650 + 0,038 x respectively, for holstein-Friesian and N'dania bulls.

A Better Approach To The Estimation Of Testicular Size In Live Boars

A MODIFIED approach in testicular biometry in boars is described. Twelve mature Large White pigs were used for this study. Half the major axis of the testis (a) and the square of half the minor axis [b2] were highly significantly correlated with both testicular weight and testicular volume. The multiple correlations between a and b2 and the testis weight and testis volume were respectively 0.94 and 0.96 and equally highly significant. The testicular weights and volumes calculated with the multiple regression equations obtained in this study accounted for 99% and 97% of the actual values respectively.

SCROTAL AND TESTICULAR DIMENSIONS IN SOME WEST AFRICAN BULLS

A series of studies were conducted to estimate testicular size from scrotal measurement and determine the relationship between testicular size, age and liveweight in some West African bulls. Repeatability estimate for scrotal circumference measurements between technicians was 0.96. scrotal circumference was highly correlated to paired testes weight (r = 0.88) and volume (r = 0.87). Testes weight and volume were reclosely related (r = 0.997) but their ration (g/cc)varied in 30 bulls from 0.962 to 1.119, with a mean and standard deviation of 1.027 + 0.029. The regression equation for estimating tests weight (Y) from scrotal circumference (X) was Y = 506.17 + 27.70X. Significant correlations existed between scrotal circumference and age (r from 0.59 to 0.79) or liveweight (r from 0.62 to 0.83) in N Dama, Bunaji and Sokoto-Gudali bulls. However, examination of the partial correlations showed that most of the age effects were attributable to changes in liveweight. Limited evidence indicate that young Bunaji bulls have larger testis than the other two breeds although they may be overtaken by Sokoto-Gudali bulls after 5 years of age

Characteristics of the onset of puberty in male kids of three breeds

The aim of the study was to trace the development of some morphological characteristics of puberty and their development up to the 44th week as well as the relationships between them, to find the best subjects based on the phenotype. Weaning weight was measured as well as their weight once a month until the 44th week. Measuring the circumference of the scrotum of experimental young bucks was performed weekly from weaning to 44 weeks of age. Monitoring of the release of the penis from the foreskin was performed weekly from weaning until the time of its full release. The average value of the circumference of the scrotum increased from the 12th week to the 39th week in total for all animals (from 15.8 to 28.4 cm), as well as by breed (BWD - 16.5 to 31 cm ), (Togenburg - 15.5 to 28.5 cm) and (Anglo-Nubian 15.8 to 26.1 cm) (p> 0.05). The variation of the trait was low throughout the study period. The earliest complete release of the penis in our study was observed in the male kids BWD breed -16 weeks. Togenburg kids reached full release at - 18 weeks. In AN kids, the release was at -24 weeks. The correlation coefficient showed a very strong reliable positive relationship between the studied factors in all three studied breeds. Testicular size and body weight could be used as a determining factor in the selection of prepubertal male kids.

Nonylphenol Induces Apoptosis through ROS/JNK Signaling in a Spermatogonia Cell Line

Nonylphenol (NP) is an endocrine-disruptor chemical that negatively affects reproductive health. Testes exposure to NP results in testicular structure disruption and a reduction in testicular size and testosterone levels. However, the effects of NP on spermatogonia in testes have not been fully elucidated. In this study, the molecular mechanisms of NP in GC-1 spermatogonia (spg) cells were investigated. We found that cell viability significantly decreased and apoptosis increased in a dose-dependent manner when GC-1 spg cells were exposed to NP. Furthermore, the expression levels of the pro-apoptotic proteins increased, whereas anti-apoptosis markers decreased in NP-exposed GC-1 spg cells. We also found that NP increased reactive oxygen species (ROS) generation, suggesting that ROS-induced activation of the MAPK signaling pathway is the molecular mechanism of NP-induced apoptosis in GC-1 spg cells. Thus, NP could induce c-Jun phosphorylation; dose-dependent expression of JNK, MKK4, p53, and p38; and the subsequent inhibition of ERK1/2 and MEK1/2 phosphorylation. The genes involved in apoptosis and JNK signaling were also upregulated in GC-1 spg cells treated with NP compared to those in the controls. Our findings suggest that NP induces apoptosis through ROS/JNK signaling in GC-1 spg cells.