Heat Stroke Research Articles

The human plasma lipidome response to exertional heat tolerance testing.

The year of 2023 displayed the highest average global temperatures since it has been recorded-the duration and severity of extreme heat are projected to increase. Rising global temperatures represent a major public health threat, especially to occupations exposed to hot environments, such as construction and agricultural workers, and first responders. Despite efforts of the scientific community, there is still a need to characterize the pathophysiological processes leading to heat related illness and develop biomarkers that can predict its onset. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based lipidomics analysis was performed on plasma from male and female subjects who underwent exertional heat tolerance testing (HTT), consisting of a 2-h treadmill walk at 5km/h with 2.0% incline at a controlled temperature of 40ºC. From HTT, heat tolerance was calculated using the physiological strain index (PSI). Nearly half of all 995 detected lipids from 27 classes were responsive to HTT. Lipid classes related to substrate utilization were predominantly affected by HTT, with a downregulation of triacylglycerols and upregulation of free fatty acids and acyl-carnitines (CARs). Even chain CAR 4:0, 14:0 and 16:1, suggested by-products of incomplete beta oxidation, and diacylglycerols displayed the highest correlation to PSI. PSI did not correlate with plasma lactate levels, suggesting that correlations between even chain CARs and PSI are related to metabolic efficiency versus physical exertion. Overall, HTT displays a strong impact on the human plasma lipidome and lipid metabolic inefficiencies may underlie reduced heat tolerance.

Heat Index Levels and Heat – Related Risks in the Philippines

Using a systematic literature review, this study determined and establish the Health Index Levels and Heat – Related Health Risks in the Philippines.  Background. The heat index which is also called as the visible temperature is well-defined as a personalized, subjective experience of a person when comparative humidity is correlated with the temperature of the air. The incidence and intensity of life-threatening incidents especially escalated heat index are growing all around the world which ultimately poses a serious risk to the health of people.  Aim. The aim of this review was to explore and deliberate the relationship between the heat index, a measure that combines air temperature and relative humidity to approximate the apparent temperature, and the risk of heat-related health issues in the Philippines from published articles between 2019 – 2024.  Data Sources. A systematic search of primary articles on numerous electronic databases that included Google Scholar and other related engines. Grey literature was also connected based on the references available and bibliographies from the different articles were also included in the pooling of literature of data.  Method. The article included two (2) or more of the key search terms identified: heat exhaustion, heat stroke, health related risks, heat index , and lastly published from years 2019-2024.  Results. Analysis of the research articles were used to answer the effect of the heat index in the risk of heat exhaustion, the effect of the heat index in the risk of stroke and formulation of research - based recommendations on Heat Index Levels and Heat - Related Health Risks in the Philippines.  Acknowledgment: The authors of this systematic literature review thanks and recognize all the writers of the variety of references that were used in this review paper. The proponents these data sources used in this paper are both cited in the text and in the reference lists.  Disclaimer: The beliefs and point of view manifested in this paper are those of the authors and do necessarily indicate the official guidelines or stand of any affiliated institution, organization or agency of the authors.  Conflict of Interest: The authors have not anything to proclaim. This paper is a collaborative effort of the authors mentioned above.

Coexisting metabolic dysfunction-associated steatotic liver disease exacerbates in-hospital outcomes in patients with heat stroke

PurposeThis study aimed to investigate the impact of coexisting metabolic dysfunction-associated steatotic liver disease (MASLD) on in-hospital mortality and organ injury markers in patients with heat stroke (HS).ApproachHS patients were retrospectively identified between July 1, 2022 and September 30, 2023 at West China Hospital, Sichuan University. Baseline characteristics, such as demographics, initial vital signs, and organ functional indicators were collected. Outcome events included organ injury and in-hospital mortality. The Least Absolute Shrinkage and Selection Operator (Lasso) method was employed to identify the optimal predictors for in-hospital mortality in HS patients. Subsequently, multivariable logistic regression analysis was performed to assess the relationship between the presence of MASLD and in-hospital mortality as well as organ function indicators.FindingsA total of 112 patients were included in the study, in which 27 (24.1%) had coexisting MASLD. Compared to those without MASLD, patients with MASLD had higher levels of various organ injury markers such as aspartate aminotransferase, urea nitrogen, serum cystatin C, creatinine, uric acid, myoglobin, creatine kinase and its isoenzymes upon admission (P < 0.05). The multivariable Logistic regression analysis indicated that the presence of MASLD is an independent risk factor for in-hospital mortality in HS patients.ConclusionThis study firstly indicated that coexisting MASLD may exacerbate organ injury in HS patients and serve as an independent risk factor for in-hospital mortality.

The Impact of Residential Building Insulation Standards on Indoor Thermal Environments and Heat-Related Illness Risks During Heatwaves: A Case Study in Korea

This study investigates the impact of building insulation standards on indoor thermal environments and the risk of heat-related illnesses during heatwaves in South Korea. Indoor temperatures were measured in residential buildings located in Chuncheon and Gwangju during the 2022 heatwave, with outdoor temperature data sourced from the Korea Meteorological Administration. Probability distribution fitting was used to estimate the likelihood of indoor temperatures exceeding the critical threshold of 27 °C. Additionally, a linear regression analysis was conducted to examine the relationship between the probability of exceeding the threshold and heat-related illness data from 2017 to 2023 provided by the Korea Disease Control and Prevention Agency. The findings reveal significant variations in indoor thermal conditions during heatwaves, influenced by factors such as building type, year of construction, and climate region, which affect the thermal insulation performance. Buildings with a lower thermal insulation performance were associated with higher indoor temperatures, increasing the likelihood of exceeding the critical threshold and contributing to a higher incidence of heat-related illnesses, particularly in provincial non-metropolitan areas. These results underscore the need for region-specific building insulation standards that address both winter energy efficiency and summer heatwave resilience. Enhancing thermal insulation in vulnerable regions could significantly reduce the risk of heat-related illnesses and improve public health resilience to extreme heat events.

Curcumin ameliorates heatstroke-induced lung injury by activating the PI3K/AKT pathway.

Heatstroke (HS) poses a significant threat to public health. Curcumin, a polyphenolic compound, has been reported to possess anti-inflammatory and antioxidant properties. This study aimed to investigate the potential therapeutic effects of curcumin on HS-induced lung injury and to elucidate its underlying molecular mechanisms. We utilized network pharmacology to predict the potential targets of curcumin and determine its possible protective effects against HS. Molecular docking was performed to assess the affinity of curcumin to proteins. Forty mice were used for in vivo experiments to evaluate the therapeutic effects of curcumin, divided into four groups (n = 10 per group): normal control (NC), high-temperature control (HTC), low-dose curcumin heatstroke (H100c, 100mg/kg/day), and high-dose curcumin heatstroke (H200c, 200mg/kg/day). Furthermore, we evaluated lung pathology, ultrastructural alterations, and protein expression levels of key molecules. Molecular docking indicated a high binding affinity between curcumin and PIK3R1, AKT, and CASP3. In vivo experiments confirm that curcumin pretreatment significantly mitigates HS-induced lung tissue pathology and ultrastructural damage, with the H200c group showing notably greater improvement. Furthermore, curcumin pretreatment markedly enhances the activation of the PI3K/AKT pathway and suppresses the expression of cleaved caspase3, particularly in the H200c group. Our study suggests curcumin may alleviate HS-induced lung injury via the PI3K/AKT pathway, but limitations exist. We did not test key protein knockdown/overexpression, and PI3K/AKT may not be the only pathway. Human and mouse pharmacokinetic differences could affect clinical translation.

Current Situation of Heat Stress Studies on Kendo Players: A Scoping Review

Background/Objectives: Global warming and the rise in the average temperature in recent years have increased the risk of heat stroke and also deteriorated performance among athletes. Kendo, a traditional Japanese martial art and also a competitive sport, is reported to have high incidents of heat stroke and related mortality. However, there is no heat management guideline for this specific sport to date and research on its heat management practices and risk factors for heat stroke are limited. The present study conducted a scoping review on studies focused on heat stress and the heat management practices of Kendo players. Methods: A literature search was conducted using five databases (PubMed, SCOPUS, Ichu-shi Web, CiNii, and Google Scholar) and also manually from the references of searched articles. Results: Overall, the studies that have investigated the heat stress of Kendo players are scarce and outdated. Of the 15 references that met screening criteria, 11 studies were conducted in a field setting. The vast majority were conducted on male university students and there was a lack of research on females and on different age groups. Common measures of heat management practices used in previous studies were weight changes before and after training (n = 14), body temperature (n = 9), and heart rate (n = 8). Only a few studies used multiple measures to determine heat stress. Conclusions: Considering the continuation of global warming and the increasing risk of heat stroke, further investigation on heat stress, its association with health and performance, and current heat management practices in Kendo players are warranted.

Combination Of Fused Machine Learning And Cascaded Levy Flight Optimization In Heat Stroke Prediction

Combination Of Fused Machine Learning And Cascaded Levy Flight Optimization In Heat Stroke Prediction

The Impact of Global Warming on the Rise in Heat-Related Illnesses in Emergency Medical Services

The Impact of Global Warming on the Rise in Heat-Related Illnesses in Emergency Medical Services

Exertional heat stroke. Are we cool enough? Retrospective observational study of patients of running events

Exertional heat stroke. Are we cool enough? Retrospective observational study of patients of running events

A case of successful pediatric heat stroke treatment using normothermic targeted temperature management

This case report describes a successful use of normothermic targeted temperature management (TTM) for the treatment of a 14-year-old girl with exertional heat stroke. Upon hospitalization, she exhibited a 40.5 ℃ core temperature and multiorgan failure. We immediately applied the TTM, targeting a range of 36-37 ℃. Her condition improved rapidly, with vital signs stabilized and consciousness fully regained by day 3. She experienced a bimodal pattern of rhabdomyolysis during recovery, which was managed without further complications. No neurological sequelae were observed, and all laboratory parameters were normalized before discharge on day 10. This case suggests the potential efficacy of normothermic TTM in pediatric heat stroke.

Evaluation of some haematological and coagulation profiles of occupationally heat stress individuals of bakery industries in Kano, Nigeria

Bakers are exposed to heat stress in their work places, which can result in a variety of outcomes ranging from mild heat cramps to heat stroke. There is paucity of published data on the wallop of heat stress on haematologic and haemostatic parameters of individuals occupationally exposed to heat stress from bakery industries. This study attempted to evaluates some haematological and coagulation parameters of bakery workers who are occupationally exposed to heat stress in the baking industries. One hundred (100) individuals who consented to participate among which are: 70 bakers and 30 non-bakers were enrolled into the study. Blood samples were obtained using aseptic venepuncture and assessed for haematologic and haemostatic parameters by Haematology-analyser for full blood count parameters and manual standard coagulation method for Prothrombin time (PT) and activated partial thromboplastin time (aPTT) respectively. The data obtained was analyzed using IBM SPSS version 23. The results are presented as mean and standard deviation and p-value was set at ≤0.05as statistically significant. Platelets, red and white blood cells counts and their indices were counted along with some coagulation parameters (PT and aPTT). A statistically significant increase (p≤0.05) in platelets counts were observed in bakers compared with controls. Similarly, some coagulation parameters were found to be reduced and was statistically significant (p≤0.05) in bakers compared with non bakers as controls. The findings of the study showed insignificant changes in haematologic parameters coupled with altered coagulation parameters. This may be suggestive that individuals occupationally exposed to heat stress are prone to hypercoagulable state and its attending consequences.

Proposing adjustments to heat safety thresholds for junior high and high school sports clubs in Japan.

With higher temperatures expected in the future due to global climate change, addressing health risks such as heat illness is increasingly important. In Japan, thousands of heat illness cases occur annually during school sports club activities. The risk may vary by sport, location, and region, but how heat safety thresholds (HSTs) should be adjusted to provide effective guidelines remains uncertain. Thus, we conducted a case-crossover study using data of heat illness cases and wet-bulb globe temperature (WBGT) throughout Japan to evaluate the heat illness risk for the current HSTs and propose adjustments. A significant relationship was found between heat illness incidence and WBGT at the time of the incident, as well as the average WBGT one and two days prior. The risk significantly varies with factors such as club, region, location, year, month, and the average WBGT in summer. Therefore, we recommend lowering the current HSTs by one category (3°C) in the following cases: (1) clubs at high risk (baseball, softball, soccer/futsal, tennis, track and field, kyudo, and other with sustained exercise or thick uniforms); (2) from April to June; (3) in cooler regions (Hokkaido, Tohoku, Hokuriku, or where the average WBGT in summer≦18℃); (4) for outdoor activities; (5) when heat rapidly increases without adequate heat acclimatization. These findings may inform educators, students, sports authorities, and policymakers in adjusting HSTs to reduce the incidence of heat illness, thereby ensuring safer environments for school sports activities.

Climate Change, Air Pollution, African Dust Impacts on Public Health and Sustainability in Europe

Abstract Climate change poses a significant threat to environmental sustainability and public health, leading to extreme weather events, rising sea levels, and biodiversity loss. Research on air pollution from African dust adversely associated with climate change highlights its significant role in trapping heat in the atmosphere and causing heat-related illnesses, cardiovascular disorders, and respiratory ailments. Smog, dust, acid rain, and ozone depletion also negatively impact ecosystems. The methods of the study also include the dynamics of climate change-induced air pollution. The implications for public health and environmental sustainability through GWR modeling and MODIS-NDVI analysis of controlling air pollution are crucial for reducing the climate crisis, safeguarding public health, and maintaining ecosystem sustainability. Results from particulate matter (PM 2.5-10), which consists of tiny particles with varying diameters, can enter the respiratory system through inhalation. This can lead to a diameter of less than 10 μm (PM 2.5-10). According to the relevant legislation, the limit value refers to the daily average value and must not exceed 50 μg/m3. While ozone in the stratosphere serves a protective function against ultraviolet radiation, excessive levels at ground level can be harmful and have been recorded in atmospheric samples ranging from 146.6 μg/m3 up to 702.3 μg/m3. impacting the respiratory and cardiovascular systems. Policy leaders, businesses, and individuals need to be proactive in reducing air pollution, adopting clean energy technology, and implementing stricter pollution rules. Stricter pollution rules, environmentally friendly transportation choices, and the adoption of clean energy technology. The sustainability of the ecosystem and public health are significantly impacted by climate change linked to air pollution. To solve these global problems and move toward a healthier, cleaner future for future generations, we must act now on climate justice. Key messages • Examine the impact of African dust air pollution on public health and its significant impacts from climate change, provide solutions to mitigate its effects on environmental sustainability in Europe. • Public health workers, Policymakers and stakeholders must prioritize reducing emissions and enforcing strict air quality laws to mitigate the negative impact of African dust on European populations.

Climate change and its health effects - an optional subject for medical students

Abstract The Standing Committee of European Doctors urged to include training on the impact of climate change on health for health professionals. Currently, in the curriculum of most medical schools, the health-related impacts of climate change represent a peripheral part. The teaching of health effects of climate change should be made part of the training of health professionals and should be introduced in the curriculum of medical schools. ClimateMed is an Erasmus project that improves the curriculum and expands knowledge about the health effects of climate change at medical universities. The World Café method, based on round table discussions, was applied to assess the needs, summarize the proposals, and develop the necessary strategy. At the same time, a questionnaire was applied to those medical students from UMFST Targu Mureș who chose this subject as an optional subject. Students related the importance of understanding the diseases caused directly or indirectly by climate change, and reported what kind of topics should be included in a new course, in which semester/module and in what format it would be appropriate to teach it. The most frequently reported topics were: excessive heat and heat-related illnesses, extreme weather, vector-borne diseases, food safety, air pollution, and mental health. According to the goals of the project and students’ opinions, since 2023 medical students can choose Climate Change and Health Effects as an elective course. Based on the demand for medical universities to include in their curriculum knowledge related to the health effects of climate change, ClimateMed project can facilitate this integration and can promote the increase of teacher motivation and the development of methodological guidelines for university teachers. The project contributes to the preparation of some educational materials and the introduction of an optional subject in the training curriculum of the students of the Faculty of Medicine, UMFST Targu Mureș. Key messages • There must be made efforts to include training on the impact of climate change on health for health professionals, to introduce this subject in the curriculum of medical schools. • ClimateMed project can facilitate the integration of knowledge about the health effects of climate change into curriculum and can promote the practical use.

Public perceptions of the health impacts of climate change: a survey study in Greece

Abstract Background Climate change is the biggest global health threat of the 21st century. Despite the tremendous challenges, many people remain unaware of the human health implications of climate change. People perceptions about the health harms of climate change can increase public support for the action needed to reduce climate change. The aim of this study was to examine the public perception of climate change as a human health issue in Greece. Methods A population survey study was conducted from October to December 2023 in the municipalities of Messini and Alexandroupoli, Greece, following proportional quota sampling. A questionnaire was developed and included measures about the socio-demographic background of participants, their understanding of key facts about climate change and their views about climate change thread to human health. Results 406 individuals with a mean age 37.7 (sd = 14.8) participated in the study. Participants understood that climate change is happening (93.6%) and 54% of them think climate change is mostly or entirely caused by human activities, whereas 38% think it is caused equally by human activities and natural causes, and about 8% think climate change is mostly or entirely caused by natural causes. A majority of participants reported that climate change has adversely affected the health of people in various way, either a moderate amount or a great deal, including physical or mental harm from forest fires (90%), physical or mental harm from storms and floods (87%), heat-related illnesses (82%), illness due to reduced outdoor air quality (70%) and loss of housing for residents displaced by extreme weather events (70%). Conclusions Participants viewed climate change as an important cause of health harm, however they partially understood that climate change is caused by humans. Public health authorities should educate the public and policymakers about the climate change and advocate for policies to address the human health challenges of climate change. Key messages • Public health authorities should educate the public and policymakers about the climate change problem and its impact to human health. • Providing people with information about the health harms of climate change can increase public support for the actions needed to reduce emissions.

Extreme Heat and Specific-Cause Mortality during Summer 2018 in Mainland Portugal

Abstract Climate change has led to increased frequency and duration of extreme heat periods, impacting human health and mortality. During the 2003 heatwave, it was estimated that there were between 25,000 and 70,000 excess deaths in Western Europe. Specific-cause mortality analysis was conducted in Portugal that year and has not been assessed since. The goal of this study is to estimate the impact of an extreme heat period in 2018 on specific-cause mortality in mainland Portugal. An ecological study was conducted comparing observed and expected deaths, from August 2 to 9, 2018, in Portugal. Two comparison periods were chosen: from July 19 to 26, 2018 (C1) and the average deaths from August 2 to 9 in 2017 and 2019 (C2). Excesses, ratios, and respective 95% confidence intervals were calculated in R. Analyses were stratified by sex, age group, and district. Consistent excess deaths were observed between comparators, showing a greater impact in circulatory diseases (C1: 283, 95% CI: 210; 356 and C2: 239, 95% CI: 164; 314) and respiratory diseases (C1: 98, 95% CI: 55; 141 and C2: 95, 95% CI: 52; 138). Regarding death ratios, with C1, the highest death ratios were observed for exposure to excessive natural heat (50.00, 95% CI: 37.11; 65.92) and ischemic stroke (4.00, 95% CI: 2.07; 6.99). With C2, the highest death ratios were observed for exposure to excessive natural heat (50.00, 95% CI 37.11; 65.92) and atherosclerosis (2.71, 95% CI 1.63; 4.24). The excesses and ratios of deaths were higher in more urbanized districts, females, and age groups above 75 years. The results suggest that the extreme heat in 2018 had an impact on mortality. Elevated death ratios and excesses were observed for various causes of death with considerable statistical magnitude and significance. These findings align with other national and international studies. Public health action is increasingly critical to mitigate the observed rise in mortality during periods of extreme heat. Key messages • Specific-cause mortality analysis during extreme heat suggests a greater impact in circulatory and respiratory diseases, in residents of urbanized districts, females, and individuals of 75+ years. • Understanding these specific causes can better inform public health actions and planning, thereby mitigating the adverse effects of extreme heat.

Rifaximin alleviates intestinal barrier disruption and systemic inflammation via the PXR/NFκB/MLCK pathway and modulates intestinal Lachnospiraceae abundance in heat-stroke mice

Heatstroke is a critical condition with a high mortality rate and intestinal barrier dysfunction is a key factor in its progression to sepsis in some patients. This study aimed to explore the protective effects of rifaximin on the intestinal barrier in heat-stroke mice and the underlying mechanisms. A mouse model of heat stroke was established, followed by rifaximin intervention. Rifaximin significantly improved survival rates, reduced core body temperature, and alleviated intestinal tissue damage. Further mechanistic studies revealed that rifaximin restored heat stroke-induced damage to intestinal barrier function by upregulating the expression of the tight junction proteins, ZO-1 and occludin. Additionally, 16S rRNA sequencing showed that rifaximin significantly increased the abundance of Lachnospiraceae in the gut and enhanced short-chain fatty acid butyrate levels. In vitro experiment results revealed that butyrate promotes the expression of the intestinal epithelial cell protein MUC2, thereby strengthening the intestinal barrier. Rifaximin also activated the pregnane X receptor (PXR) signaling pathway and inhibited the NF-κB/MLCK signaling pathway, reducing the permeability of intestinal epithelial cells. This study demonstrated that rifaximin protects the intestinal barrier in mice with heat stroke through multiple pathways by modulating the gut microbiota, increasing butyrate production, and activating the PXR signaling pathway. These findings provide a new theoretical basis for the clinical application of rifaximin in heat stroke treatment.

Evaluating the relationship between heat-related illness and cooling center location in Virginia

AbstractExtreme heat contributes to adverse health outcomes and public cooling centers are often used as both a heat-health mitigation and management strategy to protect public health during extreme heat events. While the presence of a cooling center should theoretically improve heat-health outcomes in the surrounding community, there are no quantitative studies evaluating this relationship. Using heat-related emergency department and urgent care center visits from the 2014–2020 summer seasons, this study evaluates the relationship between heat-related illness (HRI) and cooling centers in Virginia. In total, more than 10,000 incidences of HRI occurred over the period across 68% of Virginia ZIP codes as reported. Communities with a cooling center had higher rates of HRI than those without, and this difference was most significant in urban areas. This result was coincident with a significant increase in non-white residents in these ZCTA. Our results draw attention to the need for additional research on the topic of cooling center access, efficacy, and operations. Strategically locating cooling centers near or within vulnerable communities is one just consideration, and more work is needed to uncover if, when, who, and how communities are utilizing, or in many cases not utilizing or unable to utilize, cooling centers.

Summarizing Recommendations for the Prevention of Occupational Heat-Related Illness in Outdoor Workers A Scoping Review.

Outdoor workers face unique challenges in preventing heat-related illnesses (HRI). Although preventable, HRI and death from heat exposure continue. A review of the most recent recommendation for HRI prevention in outdoor workers in the United States was warranted. A scoping review using PRISMA guidelines was conducted to compile policy statements and recommendations on the prevention of HRI and synthesize them into a three-step plan for prevention using the Haddon Matrix. PubMed, CINAHL, Medline, and websites from organizations and regulating bodies were searched for sources. Key terms such as occupational OR workers OR employers OR policymakers, HRI OR heat stress OR heat, prevention, recommendations OR position statements were used. Inclusion criteria were articles published within the last 5 years written in English and containing recommendations for preventing HRI in outdoor workers. Research not based on U.S. workers was excluded from the review. Twenty sources comprised the review. Several themes emerged, indicating deficient recommendations for secondary and tertiary prevention. This review's findings can be used by occupational health nurses (OHNs) in developing comprehensive interventions for preventing HRI and injury, using clear language, and following evidenced-based practices to increase workplace health and safety and promote equity.

Heat stress: a major threat to ruminant reproduction and mitigating strategies.

Stress is an external event or condition that puts pressure on a biological system. Heat stress is defined as the combination of internal and external factors acting on an animal to cause an increase in body temperature and elicit a physiological response. Heat stress is a set of conditions caused by overexposure to or overexertion at excess ambient temperature and leads to the inability of animals to dissipate enough heat to sustain homeostasis. Heat exhaustion, heat stroke, and cramps are among the symptoms. For the majority of mammalian species, including ruminants, heat stress has a negative impact on physiological, reproductive, and nutritional requirements. Reproductive functions, including the male and female reproductive systems, are negatively affected by heat stress. It decreases libido and spermatogenic activity in males and negatively affects follicle development, oogenesis, oocyte maturation, fertilization, implantation, and embryo-fetal development in females. These effects lead to a decrease in the rate of reproduction and financial losses for the livestock industry. Understanding the impact of heat stress on reproductive tissues will aid in the development of strategies for preventing heat stress and improving reproductive functions. Modification of the microenvironment, nutritional control, genetic development of heat-tolerant breeds, hormonal treatment, estrous synchronization, timed artificial insemination, and embryo transfer are among the strategies used to reduce the detrimental effects of heat stress on reproduction. These strategies may also increase the likelihood of establishing pregnancy in farm animals.