reproductive potential
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2022 ◽  
Author(s):  
Nicholas Josiah Ens ◽  
Bronwyn Harvey ◽  
Morgan M. Davies ◽  
Hanna M. Thomson ◽  
Keegan J. Meyers ◽  
...  

The European green crab (Carcinus maenas), native to northwestern Europe and Africa, is among the top 100 most damaging invasive species globally. In some regions, including the Atlantic coast of North America, C. maenas has caused long-term degradation of eelgrass habitats and bivalve, crab, and finfish populations, while areas are near the beginning of the invasion cycle. Due to high persistence and reproductive potential of C. maenas populations, most local and regional mitigation efforts no longer strive for extirpation and instead focus on population control. Long-term monitoring and rapid response protocols can facilitate early detection of introductions that is critical to inform management decisions related to green crab control or extirpation. Once C. maenas are detected, local area managers will need to decide on management actions, including whether and what green crab control measures will be implemented, if local invasion might be prevented or extirpated, and if population reduction to achieve functional eradication is achievable. Due to the immense operational demands likely required to extirpate C. maenas populations, combined with limited resources for monitoring and removal, it is unlikely that any single government, conservation and/or academic organization would be positioned to adequately control or extirpate populations in local areas, highlighting the importance of collaborative efforts. Community-based monitoring, and emerging methods such as environmental DNA (eDNA), may help expand the spatial and temporal extent of monitoring, facilitating early detection and removal of C. maenas. While several C. maenas removal programs have succeeded in reducing their populations, to our knowledge, no program has yet successfully extirpated the invader; and the cost of any such program would likely be immense and unsustainable over the long-term. An alternative approach is functional eradication, whereby C. maenas populations are reduced below threshold levels such that ecosystem impacts are minimized. Less funding and effort would likely be required to achieve and maintain functional eradication compared to extirpation. In either case, continual control efforts will be required as C. maenas populations can quickly increase from low densities and larval re-introductions.


2022 ◽  
Vol 15 (6) ◽  
pp. 715-725
Author(s):  
S. V. Pichugova ◽  
V. A. Chereshnev ◽  
Ya. B. Beikin

Introduction. The prevalence of andrological diseases among adolescents and young adults resulting in lowered reproductive potential has been noted to progressively increase. At the same time, the number of couples starting to manage reproductive issues after 35–40 years of age highlighting the onset of male androgen deficiency continues to rise. Therefore, the analysis of spermogram as the key element in assessing male reproductive potential is better to conduct at different age periods of man's life.Aim: to compare spermogram parameters in different age groups of patients with reproductive pathology.Materials and Мethods. The analysis of spermograms in adolescents with left-sided grade II–III varicocele aged 17 years and in infertile males aged 22–48 years was performed. Semen analysis was conducted in accordance with the standards of the 5 th edition of the World Health Organization and included the following parameters: semen volume (ml), sperm concentration (million/ml), total sperm count (million), acidity, viscosity, progressive motility, total motility, viability, morphology, detected mucus, leukocytes, amyloid bodies, lecithin grains as well as sperm aggregation and agglutination. The stained preparations were used to assess the morphology of spermatozoa and spermatogenesis cells. According to the spermogram data obtained, the following conclusions were drawn: normozoospermia, oligozoospermia, asthenozoospermia, teratozoospermia. Statistical analysis was performed by using Statistica 10.0 software (StatSoft Inc., USA). The normality distribution was assessed using the χ2 test. Quantitative parameters were presented as arithmetic means and standard deviations (M ± SD). Assessing significance of differences was performed by using the Student's t-test, whereas inter-parameter correlation relations were analyzed by using the linear Pearson's correlation coefficient. A significance level between inter-group parameters was set at p < 0.05.Results. It was found that adolescents with varicocele vs. adult men had significantly decreased ejaculate volume. In particular, the average ejaculate volume in adolescents and adult men was 2.32 ± 1.22 ml and 3.50 ± 1.44 ml, respectively, so that the larger number of young patients were noted to have ejaculate volume below 1.5 ml. Compared to young subjects, aged patients had decreased sperm concentration (35.88 ± 25.74 versus 72.20 ± 49.32 million/ml) and total sperm count (120.58 ± 91.72 versus 173.07 ± 163.92 million). Young patients were found to have significantly superior data in all categories of sperm motility, whereas infertile men were diagnosed with impaired sperm motility. In particular, adolescents were featured with the average number of spermatozoa displaying fast and slow translational movement comprising 17.12 ± 11.04 % and 29.30 ± 12.29 %, respectively, the proportion of progressive motility spermatozoa was 46.20 ± 19.82 %. In contrast, similar parameters in adult men were 5.10 ± 6.36 %, 19.80 ± 9.61 %, and 24.95 ± 11.23 %, respectively. In infertile men prevalence of lacked spermatozoa with rapid forward movement was 46 (46.0 %), in adolescents – 8 (8.6%), whereas rate of immotile spermatozoa in infertile men, on average, accounted for 53.10 ± 14.56 %, in adolescents – 34.40 ± 21.83 %. In addition, adolescents with varicocele had significantly fewer spermatozoa with normal morphology – 14.14 ± 8.06 % (in adult men – 30.08 ± 17.94 %), there were more abundant defects in the sperm head – 58.01 ± 12.43 % (in men – 48.83 ± 18.95 %) and flagella – 17.24 ± 6.31 % (in men – 10.29 ± 6.21 %). The data obtained showed that adolescents were more often diagnosed with normozoospermia – in 49 (52.7 %) cases, in infertile men – in 12 (12.0 %) cases, whereas in aged men asthenozoospermia was detected in 82 (82.0 %) cases, in adolescents – 5 (5.4 %) cases.Conclusion. The abnormalities in the spermogram revealed in adolescents may be associated with unestablished spermatogenesis. Normozoospermia more common in adolescents with varicocele may evidence about preserved reproductive potential. Impaired sperm motility in aged patients seems to be related to the formation of oxidative stress and damage to spermatozoa by reactive oxygen species due to combined age-related changes, cumulation of the negative effects of environmental and lifestyle factors, as well as comorbidities.


Author(s):  
Jesse W Young ◽  
Adam D Foster ◽  
Gabrielle A Russo ◽  
Gregory A Smith ◽  
Michael T Butcher

Abstract For many animals, the juvenile stage of life can be particularly perilous. Once independent, immature animals must often complete the same basic survival functions as adults despite smaller body size and other growth-related limits on performance. Because, by definition, juveniles have yet to reproduce, we should expect strong selection for mechanisms to offset these ontogenetic limitations, allowing individuals to reach reproductive adulthood and maintain Darwinian fitness. We use an integrated ontogenetic dataset on morphology, locomotor performance, and longevity in wild cottontail rabbits (Sylvilagus floridanus, Allen 1848) to test the hypothesis that prey animals are under selective pressure to maximize juvenile performance. We predicted that 1) juveniles would accelerate more quickly than adults, allowing them to reach adult-like escape speeds, and 2) juveniles with greater levels of performance should survive for longer durations in the wild, thus increasing their reproductive potential. Using high speed video and force platform measurements, we quantified burst acceleration, escape speed, and mechanical power production in 42 wild-caught S. floridanus (29 juveniles, 13 adults; all rabbits &gt;1kg in body mass were designated to be adults, based on published growth curves and evidence of epiphyseal fusion). A subsample of 22 rabbits (16 juveniles, 6 adults) were fitted with radio-telemetry collars for documenting survivorship in the wild. We found that acceleration and escape speed peaked in the late juvenile period in S. floridanus, at an age range that coincides with a period of pronounced demographic attrition in wild populations. Differences in mass-specific mechanical power production explained ∼75% of the variation in acceleration across the dataset, indicating that juvenile rabbits outpace adults by producing more power per unit body mass. We found a positive, though non-significant, association between peak escape speed and survivorship duration in the wild, suggesting a complex relationship between locomotor performance and fitness in growing S. floridanus.


2021 ◽  
Vol 107 (7) ◽  
pp. 27-38
Author(s):  
Andrey Manakov ◽  
◽  
Pavel Suvorkov ◽  
Ilya Ermolin ◽  
◽  
...  

In the post-Soviet period, attention is paid to the depopulation problem in the Baltic States, caused by the natural decline and migration outflow. At the same time, there is a change in the amount of certain ethnic groups in the population of these states. The purpose of the study is to assess the prospects for the reproductive potential of ethnic groups in Estonia, Latvia, and Lithuania. The study was carried out within ethnic demography, a scientific discipline that has developed at the intersection of demography, ethnography, and anthropology. The article presents the results of forecasting the number of major ethnic groups in the Baltic States for the long term (until 2061) using original methodological tools. In all three Baltic states, against the background of population decline, the share of titular ethnic groups is expected to grow – the highest in Latvia, the less significant in Estonia, and the minimum in Lithuania. The share of Russians (the most significant is in Latvia) and other ethnic groups will continue to decrease due to their low reproductive potential. In general, the tendency of the Baltic countries to move away from the complex ethnic structure of the population in the Soviet period towards mono-ethnicity will continue.


Nutrients ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 185
Author(s):  
James Curtis Dring ◽  
Alicja Forma ◽  
Zuzanna Chilimoniuk ◽  
Maciej Dobosz ◽  
Grzegorz Teresiński ◽  
...  

Gynecological neoplasms pose a serious threat to women’s health. It is estimated that in 2020, there were nearly 1.3 million new cases worldwide, from which almost 50% ended in death. The most commonly diagnosed are cervical and endometrial cancers; when it comes to infertility, it affects ~48.5 million couples worldwide and the number is continually rising. Ageing of the population, environmental factors such as dietary habits, environmental pollutants and increasing prevalence of risk factors may affect the reproductive potential in women. Therefore, in order to identify potential risk factors for these issues, attention has been drawn to trace elements. Trace mineral imbalances can be caused by a variety of causes, starting with hereditary diseases, finishing with an incorrect diet or exposure to polluted air or water. In this review, we aimed to summarize the current knowledge regarding trace elements imbalances in the case of gynecologic cancers as well as female fertility and during pregnancy.


2021 ◽  
Vol 65 (6) ◽  
pp. 507-513
Author(s):  
Ravil U. Khabriev ◽  
Elmira N. Mingazova ◽  
Vasil B. Ziatdinov ◽  
Ulyana M. Lebedeva ◽  
Tatyana N. Shigabutdinova ◽  
...  

Introduction. At present, negative trends in medical and demographic indicators continue to persist in the regions of the Russian Federation, which is seen as a consequence of a decrease in the number of young people due to the demographic “hole” of the late 20th century and an increase in the incidence of the population, especially adolescence. Therefore, to develop programs for the formation and protection of the population’s reproductive health, it is of no small importance to identify the patterns of morbidity rates in the population to determine the reproductive potential of the constituent entities of the Russian Federation. Purpose. Study the trend of population morbidity, assessment of the relationship and medium-term predicted values of the birth rate and incidence of the population of certain constituent entities of the Russian Federation to assess their reproductive potential. Material and methods: statistical materials of the Federal State Statistics Service (Rosstat) in the sections “Demography” and “Healthcare”. The analysis of the dynamics of birth rate indicators and morbidity of the population was carried out. Predictive models for fertility and morbidity of the population were built based on one-factor linear regression, where the birth rate was taken as the dependent variable, and the primary morbidity was taken as the independent variable. Results. The article presents a dynamic analysis of the birth rate, the morbidity rate of the adult, child and adolescent population in four studied territories: the Republic of Tatarstan, Sakha (Yakutia), Dagestan and the Kostroma region. It was revealed that in all regions, there is a decrease in fertility rates, starting from 2014-2015. Conclusion. Based on regression models, a forecast of the birth rate was compiled, which shows that if the existing trends continue, by 2024 relative to 2018, there will be a decrease in the birth rate in the Republic of Sakha (Yakutia) by 1.2 per 1,000 population, in the Republic of Dagestan - by 0.6 per 1,000 people, in the Kostroma region - by 0.5 per 1,000 people. However, in the Republic of Tatarstan, the indicator is forecasted to be higher than in 2018 - by 0.6 per 1,000 people.


2021 ◽  
pp. 104063872110628
Author(s):  
Jane Westendorf ◽  
Bruce Wobeser ◽  
Tasha Epp

Inter- and intra-rater variability negatively affects the reliability of various histopathology grading scales used as prognostic aids in human and veterinary medicine. The Kenney–Doig categorization (grading) scale, which is used to associate equine endometrial histologic lesions with prognostic estimation of a broodmare’s reproductive potential, has not been evaluated for inter- or intra-rater variability, to our knowledge. To assess whether the Kenney–Doig system produces reliable results among observers, 8 pathologists, all with American College of Veterinary Pathologists certification, were recruited to blindly categorize the same set of 63 digital equine endometrial biopsy slides as well as to re-evaluate anonymously 21 of 63 of these slides at a later time. Cohen kappa values for pairwise comparison of final Kenney–Doig categories were −0.05 to 0.46 (unweighted) and 0.08–0.64 (weighted), with an average Light kappa of 0.19 (unweighted) and 0.36 (weighted) across all 8 pathologists, 0.14 (unweighted) and 0.33 (weighted) for pathologists at different institutions, and 0.22 (unweighted) and 0.46 (weighted) for pathologists at the same institution. Intra-class correlations measuring intra-rater agreement were 0.12–0.77 with an average of 0.55 for all 8 pathologists. We found that only slight-to-moderate inter-rater agreement and poor-to-good intra-rater agreement was produced by 8 pathologists using the Kenney–Doig scale, suggesting that the system is subject to significant observer variability and care should be taken when communicating Kenney–Doig categories to submitting clinicians with emphasis on the quality of endometrial lesions present instead of the category and associated expected foaling rate.


Genes ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 89
Author(s):  
Tongyu Zhang ◽  
Zhonghua Ning ◽  
Yu Chen ◽  
Junhui Wen ◽  
Yaxiong Jia ◽  
...  

Molting is natural adaptation to climate change in all birds, including chickens. Forced molting (FM) can rejuvenate and reactivate the reproductive potential of aged hens, but the effect of natural molting (NM) on older chickens is not clear. To explore why FM has a dramatically different effect on chickens compared with NM, the transcriptome analyses of the hypothalamus and ovary in forced molted and natural molted hens at two periods with feathers fallen and regrown were performed. Additionally, each experimental chicken was tested for serological indices. The results of serological indices showed that growth hormone, thyroid stimulating hormone, and thyroxine levels were significantly higher (p < 0.05) in forced molted hens than in natural molted hens, and calcitonin concentrations were lower in the forced molted than in the natural molted hens. Furthermore, the transcriptomic analysis revealed a large number of genes related to disease resistance and anti-aging in the two different FM and NM periods. These regulatory genes and serological indices promote reproductive function during FM. This study systematically revealed the transcriptomic and serological differences between FM and NM, which could broaden our understanding of aging, rejuvenation, egg production, and welfare issues related to FM in chickens.


Author(s):  
Yuriy Magnutov

Almost twenty years of operation of the Federal Law no. 114-FZ of July 25, 2002 “On Countering Extremist Activities” provide grounds for demonstrating the currently formed strategy of countering organized forms of extremist activity, presented in the development of the process of criminalization and criminal-legal adaptation of the acts enshrined in Articles 2821 and 2822 of the Criminal Code of the Russian Federation (hereinafter referred to as the Criminal Code of the Russian Federation). The reproductive potential embedded in them made it possible to improve the mechanisms for combating the spread of extremist communities and extremist organizations. At the same time, the continuing growth of protest sentiments, an increase in the number and an increase in the level of organization of extremist communities and extremist organizations require the continuation of modernization of the course of criminal policy in this area. This is possible both by eliminating existing intra-industry conflicts and by deeper differentiation of responsibility.


Author(s):  
Saber Ghaderpour ◽  
Rafighe Ghiasi ◽  
Hamed Heydari ◽  
Rana Keyhanmanesh

Abstract Over the past decades, obesity and infertility in men increased in parallel, and the association between both phenomena have been examined by several researchers. despite the fact that there is no agreement, obesity appears to affect the reproductive potential of men through various mechanisms, such as changes in the hypothalamic-pituitary-testicular (HPT) axis, spermatogenesis, sperm quality and/or alteration of sexual health. Leptin is a hormone produced by the adipose tissue, and its production elevates with increasing body fat. Many studies have supported the relationship between raised leptin production and reproductive function regulation. In fact, Leptin acts on the HPT axis in men at all levels. However, most obese men are insensitive to increased production of endogenous leptin and functional leptin resistance development. Recently, it has been recommended that Kisspeptin neurons mediate the leptin’s effects on the reproductive system. Kisspeptin binding to its receptor on gonadotropin-releasing hormone (GnRH) neurons, activates the mammal’s reproductive axis and stimulates GnRH release. Increasing infertility associated with obesity is probably mediated by the Kisspeptin-GnRH pathway. In this review, the link between obesity, kisspeptin, leptin, and male fertility will be discussed.


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