Journal of thermal biology最新文献_第2页

Genetic and phenotypic insights into thermal load and racing performance of Quarter Horses 四分之一马的热负荷和比赛表现的遗传和表型分析。

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-29 DOI: 10.1016/j.jtherbio.2025.104362

Mário L. Santana , Annaiza B. Bignardi , Ricardo A.S. Faria , Josineudson A.II.V. Silva

Thermal load is a major welfare and performance concern for athletic horses, as physical exertion increases internal heat production. Although several phenotypic strategies have been developed to mitigate its effects, the genetic basis of thermal tolerance in horses remains largely unexplored. This study aimed to (1) evaluate the influence of thermal indices on the racing performance of Brazilian Quarter Horses, and (2) investigate the genetic basis of thermal tolerance through the estimation of genetic parameters across temperature gradients. We analyzed 21,857 racing-time (RT) records from 5542 horses competing between 1984 and 2016 in Sorocaba, São Paulo, Brazil, a region with a mild subtropical climate. The performance of Quarter Horses improved at higher air temperatures and thermal indices, as races were held within their thermal comfort zone. Among all environmental variables, the average air temperature over the four days preceding each race (T4) explained the greatest proportion of variation in RT. A reaction norm model was applied to RT using T4 as the environmental descriptor. Both thermotolerant and heat-sensitive genotypes were identified. Heritability and additive genetic variance varied along the temperature scale, revealing heterogeneity in genetic control. A negative genetic correlation between intercept and slope indicated a trade-off between overall performance and heat tolerance. Genetic trends showed that selection for faster racing times was associated with reduced tolerance to higher thermal load in Quarter Horses. Therefore, future breeding strategies should explicitly integrate thermotolerance to maintain performance under increasingly challenging climatic conditions.

热负荷是运动马的主要福利和表现问题，因为体力消耗会增加内部产热。尽管已经开发了几种表型策略来减轻其影响，但马耐热性的遗传基础仍未得到很大程度的探索。本研究旨在(1)评估热指标对巴西四分之一马比赛表现的影响；(2)通过估计不同温度梯度的遗传参数来研究热耐受性的遗传基础。我们分析了1984年至2016年在巴西圣保罗索罗卡巴（soocaba）比赛的5542匹马的21857个比赛时间（RT）记录，这是一个亚热带气候温和的地区。四分之一马的表现在较高的气温和热指数下有所改善，因为比赛是在它们的热舒适区举行的。在所有环境变量中，每场比赛前4天的平均气温（T4）解释了RT变化的最大比例。将T4作为环境描述符应用于RT的反应范数模型。鉴定出耐热型和热敏型两种基因型。遗传力和加性遗传方差沿温度尺度变化，表明遗传控制存在异质性。截距和斜率之间呈负相关，表明综合性能与耐热性之间存在权衡关系。遗传趋势表明，选择更快的比赛时间与四分之一马对更高热负荷的耐受性降低有关。因此，未来的育种策略应明确整合耐热性，以在日益严峻的气候条件下保持性能。

{"title":"Genetic and phenotypic insights into thermal load and racing performance of Quarter Horses","authors":"Mário L. Santana , Annaiza B. Bignardi , Ricardo A.S. Faria , Josineudson A.II.V. Silva","doi":"10.1016/j.jtherbio.2025.104362","DOIUrl":"10.1016/j.jtherbio.2025.104362","url":null,"abstract":"<div><div>Thermal load is a major welfare and performance concern for athletic horses, as physical exertion increases internal heat production. Although several phenotypic strategies have been developed to mitigate its effects, the genetic basis of thermal tolerance in horses remains largely unexplored. This study aimed to (1) evaluate the influence of thermal indices on the racing performance of Brazilian Quarter Horses, and (2) investigate the genetic basis of thermal tolerance through the estimation of genetic parameters across temperature gradients. We analyzed 21,857 racing-time (RT) records from 5542 horses competing between 1984 and 2016 in Sorocaba, São Paulo, Brazil, a region with a mild subtropical climate. The performance of Quarter Horses improved at higher air temperatures and thermal indices, as races were held within their thermal comfort zone. Among all environmental variables, the average air temperature over the four days preceding each race (T4) explained the greatest proportion of variation in RT. A reaction norm model was applied to RT using T4 as the environmental descriptor. Both thermotolerant and heat-sensitive genotypes were identified. Heritability and additive genetic variance varied along the temperature scale, revealing heterogeneity in genetic control. A negative genetic correlation between intercept and slope indicated a trade-off between overall performance and heat tolerance. Genetic trends showed that selection for faster racing times was associated with reduced tolerance to higher thermal load in Quarter Horses. Therefore, future breeding strategies should explicitly integrate thermotolerance to maintain performance under increasingly challenging climatic conditions.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"136 ","pages":"Article 104362"},"PeriodicalIF":2.9,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145952432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Taurine alleviates heat stress-induced intestinal injury by inhibiting ROS-mediated endoplasmic reticulum stress in mice 牛磺酸通过抑制ros介导的内质网应激减轻小鼠热应激诱导的肠道损伤

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-24 DOI: 10.1016/j.jtherbio.2025.104363

Xixi Ren, Zhiqing Huang, Gang Jia, Hua Zhao, Xiaoling Chen

Heat stress (HS) induces intestinal injury in animals, but the underlying mechanisms are unknown. This study aimed to investigate the protective effect of taurine (TAU) on intestinal injury induced by heat stress. The heat stress model was established by maintaining mice in a constant temperature and humidity environment (41 ± 1 °C, relative humidity 50 %–60 %), with core body temperature reaching 42 °C. In the experimental design, we supplemented different doses (100, 200, and 400 mg/kg) of TAU to the mice's basal diet, while setting up two positive control groups that received intraperitoneal injections of N-acetyl-L-cysteine (NAC) and 4-phenylbutyric acid (4-PBA), respectively. The findings revealed that heat stress led to a significant upregulation of intestinal heat shock protein 70 protein expression along with higher serum corticosterone in mice. Heat stress impaired intestinal morphology, downregulated tight junction protein gene expression and increased intestinal permeability. Simultaneously, heat stress significantly decreased intestinal antioxidant capacity, caused mitochondrial dysfunction, increased the content of inflammatory cytokines and promoted apoptosis, resulting in excessive accumulation of reactive oxygen species (ROS) and triggering endoplasmic reticulum stress. However, dietary supplementation with TAU alleviated these heat stress-induced effects, and similar results were also obtained with NAC and 4-PBA. Together, TAU could inhibit the accumulation of ROS and endoplasmic reticulum stress by enhancing intestinal antioxidant capacity, decreased inflammatory responses and apoptosis, which may exert its protective effect against heat stress-induced intestinal injury.

热应激（HS）可引起动物肠道损伤，但其机制尚不清楚。本研究旨在探讨牛磺酸（TAU）对热应激引起的肠道损伤的保护作用。将小鼠置于恒温恒湿环境（41±1℃，相对湿度50% - 60%），核心体温达到42℃，建立热应激模型。在实验设计中，我们在小鼠基础日粮中添加不同剂量（100、200和400 mg/kg）的TAU，同时建立两个阳性对照组，分别腹腔注射n -乙酰- l-半胱氨酸（NAC）和4-苯基丁酸（4-PBA）。结果表明，热应激导致小鼠肠道热休克蛋白70蛋白表达显著上调，血清皮质酮水平升高。热应激损伤肠道形态，下调紧密连接蛋白基因表达，增加肠道通透性。同时，热应激显著降低肠道抗氧化能力，引起线粒体功能障碍，增加炎症细胞因子含量，促进细胞凋亡，导致活性氧（ROS）过度积累，引发内质网应激。然而，在饮食中添加TAU可以缓解这些热应激诱导的影响，NAC和4-PBA也可以获得类似的结果。TAU通过增强肠道抗氧化能力，减少炎症反应和细胞凋亡，抑制ROS的积累和内质网应激，可能对热应激引起的肠道损伤发挥保护作用。

{"title":"Taurine alleviates heat stress-induced intestinal injury by inhibiting ROS-mediated endoplasmic reticulum stress in mice","authors":"Xixi Ren, Zhiqing Huang, Gang Jia, Hua Zhao, Xiaoling Chen","doi":"10.1016/j.jtherbio.2025.104363","DOIUrl":"10.1016/j.jtherbio.2025.104363","url":null,"abstract":"<div><div>Heat stress (HS) induces intestinal injury in animals, but the underlying mechanisms are unknown. This study aimed to investigate the protective effect of taurine (TAU) on intestinal injury induced by heat stress. The heat stress model was established by maintaining mice in a constant temperature and humidity environment (41 ± 1 °C, relative humidity 50 %–60 %), with core body temperature reaching 42 °C. In the experimental design, we supplemented different doses (100, 200, and 400 mg/kg) of TAU to the mice's basal diet, while setting up two positive control groups that received intraperitoneal injections of N-acetyl-L-cysteine (NAC) and 4-phenylbutyric acid (4-PBA), respectively. The findings revealed that heat stress led to a significant upregulation of intestinal heat shock protein 70 protein expression along with higher serum corticosterone in mice. Heat stress impaired intestinal morphology, downregulated tight junction protein gene expression and increased intestinal permeability. Simultaneously, heat stress significantly decreased intestinal antioxidant capacity, caused mitochondrial dysfunction, increased the content of inflammatory cytokines and promoted apoptosis, resulting in excessive accumulation of reactive oxygen species (ROS) and triggering endoplasmic reticulum stress. However, dietary supplementation with TAU alleviated these heat stress-induced effects, and similar results were also obtained with NAC and 4-PBA. Together, TAU could inhibit the accumulation of ROS and endoplasmic reticulum stress by enhancing intestinal antioxidant capacity, decreased inflammatory responses and apoptosis, which may exert its protective effect against heat stress-induced intestinal injury.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104363"},"PeriodicalIF":2.9,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145842062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High mountains are more than cold peaks: Diverse thermal availability for an endemic lizard 高山不仅仅是寒冷的山峰：对一种特有的蜥蜴来说，不同的热可利用性

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-23 DOI: 10.1016/j.jtherbio.2025.104367

Guadalupe López Juri , José M. Sánchez , Rafael A. Lara-Reséndiz , Sergio Naretto

引用次数: 0

The effects of improving barn cooling on the behaviour, physiological responses, gene expression, and milk yield of dairy cows 改善牲口棚降温对奶牛行为、生理反应、基因表达和产奶量的影响

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-23 DOI: 10.1016/j.jtherbio.2025.104364

Viktor Jurkovich , Szilvia Szalai , Zsóka Várhidi , Szilvia Kusza , Zoltán Bagi , Lilla Bodrogi , Blanka Dávid , Mária Kovács-Weber , Róbert Kővágó , Mikolt Bakony , Péter Hejel

Heat stress poses a significant challenge for dairy cows, particularly in warm climates, as it hampers their physiology, behaviour, and milk production. This study evaluated the effectiveness of a modern barn cooling system equipped with temperature-dependent fans in alleviating heat stress and enhancing cow welfare and productivity. The research was conducted on a large-scale Holstein Friesian dairy farm, comparing two high-yielding groups of around 100 cows each. The experimental group was housed in a barn with newly installed louvered, temperature-dependent circulation fans (providing high airspeed), while the control group remained in a barn with box ventilators (low airspeed). Data were collected over four three-day sampling periods during the summer. Environmental conditions were monitored using data loggers that recorded temperature and humidity, enabling calculation of the temperature-humidity index (THI). Cow body temperature was measured intravaginally. Additionally, time spent lying, eating, and ruminating was also tracked. Daily milk yields were obtained from the farm's database. Blood samples were also taken for gene expression measurements. Results indicated that THI values in both barns frequently surpassed the heat stress threshold (THI >68), yet air velocity in the experimental barn was notably higher (1.5–2.5 m/s) than in the control barn (0.2–0.5 m/s). Cows in the cooled barn showed significantly lower body temperatures in three of four periods. While lying time did not vary significantly, eating time increased in the experimental group later in the study. Moreover, milk yield was approximately 3 L/day higher (p < 0.05) in the experimental group. Enhanced ventilation led to complex changes in gene expression patterns, suggesting dynamic cellular responses to improved environmental conditions. These outcomes indicate that improved ventilation effectively reduces heat stress and supports better health, feeding behaviour, and milk production in dairy cows.

热应激对奶牛构成了重大挑战，特别是在温暖的气候中，因为它会影响它们的生理、行为和产奶量。本研究评估了配备温度依赖风扇的现代牛舍冷却系统在缓解热应激和提高奶牛福利和生产力方面的有效性。这项研究是在一个大型荷斯坦弗里西亚奶牛场进行的，比较了两个高产组，每个组约100头奶牛。实验组被安置在一个装有新安装的百叶、温度依赖循环风扇的谷仓里（提供高空速），而对照组则被安置在一个装有箱形通风机的谷仓里（低空速）。数据是在夏季四个为期三天的采样期收集的。使用记录温度和湿度的数据记录仪监测环境条件，从而计算温湿度指数（THI）。阴道内测量奶牛体温。此外，撒谎、进食和沉思的时间也被追踪。每日产奶量从农场的数据库中获取。血液样本也被用于基因表达测量。结果表明，两个仓的THI值都经常超过热应力阈值（THI >68），但实验仓的空气速度（1.5 ~ 2.5 m/s）明显高于对照仓（0.2 ~ 0.5 m/s）。在降温的牛棚里，奶牛的体温在四个时期中的三个时期明显降低。虽然躺着的时间没有显著变化，但在研究后期，实验组的进食时间增加了。另外，试验组产奶量比对照组高约3 L/d （p < 0.05）。增强的通风导致基因表达模式的复杂变化，表明对改善的环境条件的动态细胞反应。这些结果表明，改善通风可以有效地减少热应激，并有助于奶牛的健康、摄食行为和产奶量。

{"title":"The effects of improving barn cooling on the behaviour, physiological responses, gene expression, and milk yield of dairy cows","authors":"Viktor Jurkovich , Szilvia Szalai , Zsóka Várhidi , Szilvia Kusza , Zoltán Bagi , Lilla Bodrogi , Blanka Dávid , Mária Kovács-Weber , Róbert Kővágó , Mikolt Bakony , Péter Hejel","doi":"10.1016/j.jtherbio.2025.104364","DOIUrl":"10.1016/j.jtherbio.2025.104364","url":null,"abstract":"<div><div>Heat stress poses a significant challenge for dairy cows, particularly in warm climates, as it hampers their physiology, behaviour, and milk production. This study evaluated the effectiveness of a modern barn cooling system equipped with temperature-dependent fans in alleviating heat stress and enhancing cow welfare and productivity. The research was conducted on a large-scale Holstein Friesian dairy farm, comparing two high-yielding groups of around 100 cows each. The experimental group was housed in a barn with newly installed louvered, temperature-dependent circulation fans (providing high airspeed), while the control group remained in a barn with box ventilators (low airspeed). Data were collected over four three-day sampling periods during the summer. Environmental conditions were monitored using data loggers that recorded temperature and humidity, enabling calculation of the temperature-humidity index (THI). Cow body temperature was measured intravaginally. Additionally, time spent lying, eating, and ruminating was also tracked. Daily milk yields were obtained from the farm's database. Blood samples were also taken for gene expression measurements. Results indicated that THI values in both barns frequently surpassed the heat stress threshold (THI >68), yet air velocity in the experimental barn was notably higher (1.5–2.5 m/s) than in the control barn (0.2–0.5 m/s). Cows in the cooled barn showed significantly lower body temperatures in three of four periods. While lying time did not vary significantly, eating time increased in the experimental group later in the study. Moreover, milk yield was approximately 3 L/day higher (p < 0.05) in the experimental group. Enhanced ventilation led to complex changes in gene expression patterns, suggesting dynamic cellular responses to improved environmental conditions. These outcomes indicate that improved ventilation effectively reduces heat stress and supports better health, feeding behaviour, and milk production in dairy cows.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104364"},"PeriodicalIF":2.9,"publicationDate":"2025-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Using drone-based infrared thermography for monitoring vital signs in dolphins 利用无人机红外热像仪监测海豚的生命体征

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-16 DOI: 10.1016/j.jtherbio.2025.104353

Charlie White , Andrew P. Colefax , Guido J. Parra

Monitoring wild animal health is essential for assessing environmental threats. Physiological parameters such as body temperature and respiration rate provide critical insights into an animal's condition but collecting these from free-ranging species is challenging. This study validated drone-based infrared thermography (drone-IRT) as a non-invasive method for estimating dolphin vital signs, evaluating its accuracy, reliability, and practical application. Using a multirotor drone with an integrated thermal camera, we obtained thermographic images of 14 common bottlenose dolphins (Tursiops truncatus) under human care. Flights were conducted in Austral summer and winter at heights of 5 m–30 m, with the camera angled at 0° (zenith) and 50° pitch. Dolphins were either swimming freely or beached. From thermal images, we extracted temperatures based on the heat received from the blowhole, body, and dorsal fin, along with respiration rate estimates. Close-range IRT reference temperatures and environmental variables were recorded throughout each flight. Robust linear mixed-effects models assessed the influence of flight and environmental variables on measurement accuracy and precision. Spearman's rank correlation evaluated the relationship between drone-IRT blowhole temperature and rectal temperature. Drone-IRT measurements closely matched close-range IRT reference values. The most reliable temperature estimates occurred at a combined 10 m and a 0° angle (accuracy: −0.19 °C – 0.08 °C, precision: −0.07 °C – 0.08 °C). The most accurate respiration rate estimates were obtained at 10 m while dolphins swam freely. A weak negative correlation was found between blowhole and rectal temperatures (r = −0.19). This study demonstrates that drone-IRT is a reliable, non-invasive method for monitoring dolphins' surface temperature and respiration rates, but not rectal temperature.

监测野生动物健康对于评估环境威胁至关重要。体温和呼吸速率等生理参数为了解动物状况提供了关键的信息，但从自由放养的物种中收集这些数据是具有挑战性的。本研究验证了基于无人机的红外热像仪（drone-IRT）作为一种非侵入性的海豚生命体征评估方法，评估了其准确性、可靠性和实际应用。利用集成热像仪的多旋翼无人机，获得了人类照料下14只普通宽吻海豚（Tursiops truncatus）的热像图。飞行在南方夏季和冬季进行，高度为5米至30米，相机角度为0°（天顶）和50°俯仰。海豚要么在自由地游泳，要么在海滩上搁浅。从热图像中，我们根据从气孔、身体和背鳍接收的热量以及呼吸速率估计提取温度。近距离IRT参考温度和环境变量在每次飞行中都被记录下来。鲁棒线性混合效应模型评估了飞行和环境变量对测量精度和精度的影响。Spearman等级相关评价了无人机- irt喷气孔温度与直肠温度之间的关系。无人机IRT测量值与近距离IRT参考值非常匹配。最可靠的温度估计发生在10米和0°角（精度：- 0.19°C - 0.08°C，精度：- 0.07°C - 0.08°C）。最准确的呼吸速率估计是在海豚自由游泳时在10米处获得的。气孔温度与直肠温度呈弱负相关（r = - 0.19）。这项研究表明，无人机irt是一种可靠的，非侵入性的方法，用于监测海豚的表面温度和呼吸速率，但不是直肠温度。

{"title":"Using drone-based infrared thermography for monitoring vital signs in dolphins","authors":"Charlie White , Andrew P. Colefax , Guido J. Parra","doi":"10.1016/j.jtherbio.2025.104353","DOIUrl":"10.1016/j.jtherbio.2025.104353","url":null,"abstract":"<div><div>Monitoring wild animal health is essential for assessing environmental threats. Physiological parameters such as body temperature and respiration rate provide critical insights into an animal's condition but collecting these from free-ranging species is challenging. This study validated drone-based infrared thermography (drone-IRT) as a non-invasive method for estimating dolphin vital signs, evaluating its accuracy, reliability, and practical application. Using a multirotor drone with an integrated thermal camera, we obtained thermographic images of 14 common bottlenose dolphins (<em>Tursiops truncatus)</em> under human care. Flights were conducted in Austral summer and winter at heights of 5 m–30 m, with the camera angled at 0° (zenith) and 50° pitch. Dolphins were either swimming freely or beached. From thermal images, we extracted temperatures based on the heat received from the blowhole, body, and dorsal fin, along with respiration rate estimates. Close-range IRT reference temperatures and environmental variables were recorded throughout each flight. Robust linear mixed-effects models assessed the influence of flight and environmental variables on measurement accuracy and precision. Spearman's rank correlation evaluated the relationship between drone-IRT blowhole temperature and rectal temperature. Drone-IRT measurements closely matched close-range IRT reference values. The most reliable temperature estimates occurred at a combined 10 m and a 0° angle (accuracy: −0.19 °C – 0.08 °C, precision: −0.07 °C – 0.08 °C). The most accurate respiration rate estimates were obtained at 10 m while dolphins swam freely. A weak negative correlation was found between blowhole and rectal temperatures (r = −0.19). This study demonstrates that drone-IRT is a reliable, non-invasive method for monitoring dolphins' surface temperature and respiration rates, but not rectal temperature.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104353"},"PeriodicalIF":2.9,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145799181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Extra food buffers thermoregulatory costs during early development but does not reduce heatwave-induced mortality in nestlings of a cavity-nesting raptor 额外的食物缓冲了早期发育过程中的体温调节成本，但并不能降低穴居猛禽雏鸟因热浪引起的死亡率

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-16 DOI: 10.1016/j.jtherbio.2025.104361

Alejandro Corregidor-Castro , Alessandro Berlusconi , Erica Figus , Anna Kyriakopoulou , Jacopo G. Cecere , Michelangelo Morganti , Diego Rubolini , Andrea Pilastro , Andrea Romano

Global climate change is increasing both average temperatures and the occurrence of extreme weather events, such as heatwaves. These changes pose major challenges for wildlife, especially during vulnerable life stages. In altricial bird species, nest-bound offspring are particularly susceptible to thermal stress due to limited behavioural thermoregulation, where high nest temperatures can impair development and induce elevated mortality, particularly when exceeding critical thresholds. We experimentally manipulated nest temperature and food availability in lesser kestrels (Falco naumanni) rearing their nestlings in nest boxes to investigate whether compensatory feeding offsets the negative effects of high nest temperatures on offspring size and pre-fledging survival. Nestlings were reared under three conditions: control (high nest temperatures), shaded (reduced temperature), and food-supplemented (high temperature with extra food). While parental provisioning rates did not differ among experimental groups, nestlings in food-supplemented boxes showed greater body size than control nestlings, despite similar thermal exposure, and matched the size of nestlings in shaded boxes. This indicates that increased food can buffer the energetic costs of thermoregulation under elevated, but non-lethal, temperatures. Mortality during development did not differ significantly among groups, as temperatures remained below critical thresholds. However, during a naturally occurring heatwave, mortality in control and food-supplemented nests was similarly high (∼40 %), whereas it was very limited in shaded nest boxes (∼4 %). These results suggest that food supplementation cannot prevent heatwave-induced mortality, likely caused by hyperthermia rather than starvation/dehydration. Nest microclimate may thus play a key role in mitigating the negative impacts of intense heatwaves in avian species.

全球气候变化正在增加平均气温和极端天气事件的发生，如热浪。这些变化对野生动物构成了重大挑战，特别是在脆弱的生命阶段。在晚育鸟类中，由于有限的行为体温调节，巢内的后代特别容易受到热应激的影响，巢内的高温会损害发育并导致死亡率升高，特别是在超过临界阈值时。为了研究补偿性喂养是否能抵消高巢温度对雏鸟大小和雏鸟成活率的负面影响，对在巢箱中饲养雏鸟的小红隼（Falco naumanni）进行了调节巢温和食物供应的实验。雏鸟在三种条件下饲养：对照（巢温高）、遮荫（温度降低）和食物补充（高温加额外食物）。虽然各组间的亲代供给率没有差异，但在热暴露相似的情况下，食物补充箱中的雏鸟比对照组雏鸟的体型更大，并且与阴影箱中的雏鸟的体型相匹配。这表明，在升高但非致命的温度下，增加食物可以缓冲体温调节的能量消耗。由于温度保持在临界阈值以下，各组之间发育期间的死亡率没有显著差异。然而，在自然发生的热浪期间，对照巢和食物补充巢的死亡率同样高（~ 40%），而在阴暗的巢箱中，死亡率非常有限（~ 4%）。这些结果表明，食物补充不能防止热浪引起的死亡，可能是由高温而不是饥饿/脱水引起的。因此，巢微气候可能在减轻强烈热浪对鸟类的负面影响方面发挥关键作用。

{"title":"Extra food buffers thermoregulatory costs during early development but does not reduce heatwave-induced mortality in nestlings of a cavity-nesting raptor","authors":"Alejandro Corregidor-Castro , Alessandro Berlusconi , Erica Figus , Anna Kyriakopoulou , Jacopo G. Cecere , Michelangelo Morganti , Diego Rubolini , Andrea Pilastro , Andrea Romano","doi":"10.1016/j.jtherbio.2025.104361","DOIUrl":"10.1016/j.jtherbio.2025.104361","url":null,"abstract":"<div><div>Global climate change is increasing both average temperatures and the occurrence of extreme weather events, such as heatwaves. These changes pose major challenges for wildlife, especially during vulnerable life stages. In altricial bird species, nest-bound offspring are particularly susceptible to thermal stress due to limited behavioural thermoregulation, where high nest temperatures can impair development and induce elevated mortality, particularly when exceeding critical thresholds. We experimentally manipulated nest temperature and food availability in lesser kestrels (<em>Falco naumanni</em>) rearing their nestlings in nest boxes to investigate whether compensatory feeding offsets the negative effects of high nest temperatures on offspring size and pre-fledging survival. Nestlings were reared under three conditions: control (high nest temperatures), shaded (reduced temperature), and food-supplemented (high temperature with extra food). While parental provisioning rates did not differ among experimental groups, nestlings in food-supplemented boxes showed greater body size than control nestlings, despite similar thermal exposure, and matched the size of nestlings in shaded boxes. This indicates that increased food can buffer the energetic costs of thermoregulation under elevated, but non-lethal, temperatures. Mortality during development did not differ significantly among groups, as temperatures remained below critical thresholds. However, during a naturally occurring heatwave, mortality in control and food-supplemented nests was similarly high (∼40 %), whereas it was very limited in shaded nest boxes (∼4 %). These results suggest that food supplementation cannot prevent heatwave-induced mortality, likely caused by hyperthermia rather than starvation/dehydration. Nest microclimate may thus play a key role in mitigating the negative impacts of intense heatwaves in avian species.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104361"},"PeriodicalIF":2.9,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145799180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal ecology and embryonic development in black caiman’s (Melanosuchus niger, Spix 1758) 黑凯门鳄（Melanosuchus niger, Spix 1758）的热生态与胚胎发育。

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-15 DOI: 10.1016/j.jtherbio.2025.104357

Helena Gurjão Pinheiro Do Val , Luiza Figueiredo Passos , Joilson Medeiros de Barros , Grahame Webb , Marcos Eduardo Coutinho

The black caiman (Melanosuchus niger, Spix, 1825) is a crocodilian species endemic to the Amazon biome, that nests within a defined nesting season bridging the local dry and wet seasons. Eggs are deposited in a mound of fresh and old vegetation, but little is known about the thermal relations of M. niger nests and their influence on embryo development rates and total incubation time. We present data for 7 wild nests from the southwestern Brazilian Amazon, gathered in 2019 and 2024. The mean incubation period from laying to hatching was 77.1 ± 8.3 days (SD; range 71.3–93.8 days). Nest temperatures were subject to daily cycling and baseline shifts over time, and had an overall mean of 31.6 ± 1.65 °C (range 27.2 °C–35.9 °C). The nests insulate and buffer the eggs against ambient temperature extremes. Mean nest temperature increases with nest size, and precipitation causes baseline declines in temperature. High nest temperatures (33.6 ± 1.39 °C) in one nest disrupted normal embryo development, and may have affected another. Embryo development rates within 6 nests, and their interactions with nest temperatures, survival to hatching and development time between laying and hatching are investigated. Based on nest temperatures we consider it likely that the M. niger nests we studied would have produced hatchlings with a female bias but could not confirm it.

黑凯门鳄（Melanosuchus niger, Spix, 1825）是一种亚马逊生物群系特有的鳄鱼物种，它们在一个确定的筑巢季节筑巢，连接当地的干湿季节。卵沉积在一堆新鲜和古老的植被中，但对黑乳杆菌巢穴的热关系及其对胚胎发育率和总孵化时间的影响知之甚少。我们展示了2019年和2024年在巴西亚马逊西南部收集的7个野生巢穴的数据。产蛋至孵化平均潜伏期为77.1±8.3天（SD；范围71.3 ~ 93.8天）。巢内温度受每日循环和基线随时间变化的影响，总体平均值为31.6±1.65°C（范围27.2°C-35.9°C）。巢将蛋与外界极端温度隔绝，并起到缓冲作用。巢的平均温度随着巢的大小而增加，而降水导致温度基线下降。一个巢的高温（33.6±1.39°C）破坏了正常的胚胎发育，并可能影响到另一个巢。研究了6个巢内的胚胎发育率及其与巢内温度、孵化存活率和孵化间发育时间的相互作用。根据巢温，我们认为我们所研究的黑乳杆菌巢可能会产生雌性偏向的幼雏，但无法证实这一点。

{"title":"Thermal ecology and embryonic development in black caiman’s (Melanosuchus niger, Spix 1758)","authors":"Helena Gurjão Pinheiro Do Val , Luiza Figueiredo Passos , Joilson Medeiros de Barros , Grahame Webb , Marcos Eduardo Coutinho","doi":"10.1016/j.jtherbio.2025.104357","DOIUrl":"10.1016/j.jtherbio.2025.104357","url":null,"abstract":"<div><div>The black caiman (<em>Melanosuchus niger</em>, Spix, 1825) is a crocodilian species endemic to the Amazon biome, that nests within a defined nesting season bridging the local dry and wet seasons. Eggs are deposited in a mound of fresh and old vegetation, but little is known about the thermal relations of <em>M. niger</em> nests and their influence on embryo development rates and total incubation time. We present data for 7 wild nests from the southwestern Brazilian Amazon, gathered in 2019 and 2024. The mean incubation period from laying to hatching was 77.1 ± 8.3 days (SD; range 71.3–93.8 days). Nest temperatures were subject to daily cycling and baseline shifts over time, and had an overall mean of 31.6 ± 1.65 °C (range 27.2 °C–35.9 °C). The nests insulate and buffer the eggs against ambient temperature extremes. Mean nest temperature increases with nest size, and precipitation causes baseline declines in temperature. High nest temperatures (33.6 ± 1.39 °C) in one nest disrupted normal embryo development, and may have affected another. Embryo development rates within 6 nests, and their interactions with nest temperatures, survival to hatching and development time between laying and hatching are investigated. Based on nest temperatures we consider it likely that the <em>M. niger</em> nests we studied would have produced hatchlings with a female bias but could not confirm it.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104357"},"PeriodicalIF":2.9,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145819889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Plasticity and regional heterothermy of upper thermal tolerance in the ring-necked snake 环颈蛇上部耐热性的可塑性和区域异质性。

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-15 DOI: 10.1016/j.jtherbio.2025.104354

Christian L. Cox , Kelly Lin Wuthrich , Dareen Aloudeh , Samuel J. Baker , Anna G. Climo , Alexa F. Gross , Christian W. Kizer , Zoe M. Korff , Oscar Melendez Vera , Veronica Y. Silva , Alexis M. Spans , Grace R. Thilenius , Ian T. Clifton , Albert K. Chung

Phenotypic plasticity of upper and lower thermal tolerance during parts of the annual cycle with high variation and unpredictability should theoretically be important for temperate ectotherms. However, whether thermal tolerance is plastic is unclear for most ectotherms. In addition, many ectotherms have regional heterothermy (variation in body temperature among body regions), and yet how regional heterothermy might impact plasticity of thermal tolerance is unknown. We studied the plasticity of upper thermal tolerance in response to warm temperatures in a population of the temperately distributed ring-necked snake (Diadophis punctatus) that exhibits regional heterothermy whereby head temperatures are substantially warmer than cloaca temperatures. We measured voluntary thermal maximum (VT_max, a measure of upper thermal tolerance) of ring-necked snakes, incubated ring-necked snakes at two temperatures (30 °C or 34 °C) at two durations (1 h or 3 h), and remeasured VT_max. We found that ring-necked snakes exhibited plasticity of VT_max even for short durations at relatively mild but warmer temperatures. We also found that the VT_max measured in the mouth was substantially higher than that measured in the cloaca, and that mouth VT_max was less plastic than cloacal VT_max. Together, these results suggest that at least some temperate ectotherms can exhibit plasticity of upper thermal tolerance in response to warm temperatures, and that interpretations of plasticity of VT_max depend on where temperature is measured in species with regional heterothermy. These findings have implications for understanding how variation in plasticity of thermal tolerance among body regions might impact the biological response to rapid environmental change.

在高变化和不可预测的年周期中，温带变温动物的上下耐热性的表型可塑性理论上应该是重要的。然而，对于大多数变温动物来说，耐热性是否具有可塑性尚不清楚。此外，许多变温动物具有区域异温性（体温在身体各区域之间的差异），但区域异温如何影响热耐受的可塑性尚不清楚。我们研究了温带分布的环颈蛇（Diadophis punctatus）种群对温暖温度响应的上耐热性的可塑性，该种群表现出区域异温性，即头部温度明显高于泄殖腔温度。我们测量了环颈蛇的自愿热最大值（VTmax，一种测量上热耐量的指标），在两个温度（30°C或34°C）下孵育的环颈蛇在两个持续时间（1小时或3小时），并重新测量了VTmax。我们发现环颈蛇在相对温和但温暖的温度下即使在短时间内也表现出VTmax的可塑性。我们还发现口腔测得的VTmax比泄殖腔测得的要高得多，而且口腔的VTmax比泄殖腔的VTmax更具可塑性。总之，这些结果表明，至少一些温带变温动物可以表现出对温暖温度的上热耐受性的可塑性，并且对VTmax可塑性的解释取决于在具有区域异温性的物种中测量温度的位置。这些发现对于理解身体各区域热耐受性可塑性的变化如何影响对快速环境变化的生物反应具有重要意义。

{"title":"Plasticity and regional heterothermy of upper thermal tolerance in the ring-necked snake","authors":"Christian L. Cox , Kelly Lin Wuthrich , Dareen Aloudeh , Samuel J. Baker , Anna G. Climo , Alexa F. Gross , Christian W. Kizer , Zoe M. Korff , Oscar Melendez Vera , Veronica Y. Silva , Alexis M. Spans , Grace R. Thilenius , Ian T. Clifton , Albert K. Chung","doi":"10.1016/j.jtherbio.2025.104354","DOIUrl":"10.1016/j.jtherbio.2025.104354","url":null,"abstract":"<div><div>Phenotypic plasticity of upper and lower thermal tolerance during parts of the annual cycle with high variation and unpredictability should theoretically be important for temperate ectotherms. However, whether thermal tolerance is plastic is unclear for most ectotherms. In addition, many ectotherms have regional heterothermy (variation in body temperature among body regions), and yet how regional heterothermy might impact plasticity of thermal tolerance is unknown. We studied the plasticity of upper thermal tolerance in response to warm temperatures in a population of the temperately distributed ring-necked snake (<em>Diadophis punctatus</em>) that exhibits regional heterothermy whereby head temperatures are substantially warmer than cloaca temperatures. We measured voluntary thermal maximum (VT<sub>max</sub>, a measure of upper thermal tolerance) of ring-necked snakes, incubated ring-necked snakes at two temperatures (30 °C or 34 °C) at two durations (1 h or 3 h), and remeasured VT<sub>max</sub>. We found that ring-necked snakes exhibited plasticity of VT<sub>max</sub> even for short durations at relatively mild but warmer temperatures. We also found that the VT<sub>max</sub> measured in the mouth was substantially higher than that measured in the cloaca, and that mouth VT<sub>max</sub> was less plastic than cloacal VT<sub>max</sub>. Together, these results suggest that at least some temperate ectotherms can exhibit plasticity of upper thermal tolerance in response to warm temperatures, and that interpretations of plasticity of VT<sub>max</sub> depend on where temperature is measured in species with regional heterothermy. These findings have implications for understanding how variation in plasticity of thermal tolerance among body regions might impact the biological response to rapid environmental change.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104354"},"PeriodicalIF":2.9,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145827642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sex and reproductive condition shape thermal acclimation strategy in a plethodontid salamander 性别和生殖条件决定了多齿蝾螈的热适应策略。

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-15 DOI: 10.1016/j.jtherbio.2025.104356

Kevin J. Moore, Brittany M. Winter, Jeanette B. Moss

The question of whether males and females differ in their responses to temperature is essential to understanding adaptive capacities in a warming world. However, sex has traditionally been neglected in the field of thermal ecology, and our understanding of the factors that promote sex differences in thermal plasticity is underdeveloped. Here, we investigate the independent and interactive effects of sex and reproductive condition on thermal acclimation capacity in a plethodontid salamander (Plethodon cinereus). We carried out two stop-flow respirometry experiments, with salamanders acclimated to one of two thermal environments designed to simulate a ‘Cold’ or ‘Warm’ breeding season. In the first experiment, we compared the thermal acclimation responses of males and gravid females across a gradient of three ecologically relevant test temperatures and observed distinct patterns of sexual dimorphism of metabolic rate (

\dot{V}

O2) between thermal treatments that were not attributable to differences in body size. Specifically, warm-acclimated gravid females showed significant reductions

\dot{V}

O₂ compared to cold-acclimated counterparts, exposing pronounced sexual dimorphism in mass-adjusted metabolic rates at higher test temperatures. In the second experiment, we expanded on our initial findings by directly testing the contribution of reproductive condition to observed sex differences in thermal acclimation capacity. By repeating the experiment of the early breeding season but including a third group of non-gravid females, we: (1) recapitulated our original finding – that gravid females exhibit a stronger response to thermal acclimation relative to males; and (2) showed that female thermal acclimation responses are absent in nongravid females, and therefore responses are contingent on reproductive condition. Taken together, our results provide a first glimpse into how sex and reproductive condition contribute to intraspecific variation in thermal acclimation capacity in an amphibian, and underscore the need for more hypothesis-driven studies to directly test when, where, and how such patterns arise.

男性和女性对温度的反应是否不同，这个问题对于理解全球变暖的适应能力至关重要。然而，在热生态学领域，性别一直被忽视，我们对促进热可塑性性别差异的因素的认识还不充分。在此，我们研究了性别和生殖条件对多齿蝾螈（Plethodon cinereus）热适应能力的独立和交互影响。我们进行了两次停止流动呼吸测量实验，蝾螈适应了两种热环境中的一种，以模拟“冷”或“暖”的繁殖季节。在第一个实验中，我们比较了雄性和妊娠雌性在三种生态相关测试温度梯度下的热驯化反应，并观察到不同热处理过程中代谢率（V˙O2）的不同性别二态性模式，而这种模式与体型差异无关。具体来说，与冷驯化的母鼠相比，热驯化的母鼠表现出显著的V˙O2降低，这表明在较高的测试温度下，质量调节代谢率存在明显的性别二态性。在第二个实验中，我们扩展了最初的研究结果，直接测试了生殖条件对观察到的热适应能力的性别差异的贡献。通过重复繁殖季节早期的实验，但包括第三组未怀孕的雌性，我们：(1)重申了我们最初的发现——怀孕的雌性相对于雄性表现出更强的热适应反应；(2)表明雌性热驯化反应在未怀孕的雌性中不存在，因此雌性热驯化反应取决于生殖条件。综上所述，我们的研究结果首次揭示了两性和生殖条件如何影响两栖动物热适应能力的种内变化，并强调了对更多假设驱动的研究的需求，以直接测试这种模式何时、何地以及如何出现。

{"title":"Sex and reproductive condition shape thermal acclimation strategy in a plethodontid salamander","authors":"Kevin J. Moore, Brittany M. Winter, Jeanette B. Moss","doi":"10.1016/j.jtherbio.2025.104356","DOIUrl":"10.1016/j.jtherbio.2025.104356","url":null,"abstract":"<div><div>The question of whether males and females differ in their responses to temperature is essential to understanding adaptive capacities in a warming world. However, sex has traditionally been neglected in the field of thermal ecology, and our understanding of the factors that promote sex differences in thermal plasticity is underdeveloped. Here, we investigate the independent and interactive effects of sex and reproductive condition on thermal acclimation capacity in a plethodontid salamander (<em>Plethodon cinereus</em>). We carried out two stop-flow respirometry experiments, with salamanders acclimated to one of two thermal environments designed to simulate a ‘Cold’ or ‘Warm’ breeding season. In the first experiment, we compared the thermal acclimation responses of males and gravid females across a gradient of three ecologically relevant test temperatures and observed distinct patterns of sexual dimorphism of metabolic rate (<span><math><mrow><mover><mi>V</mi><mo>˙</mo></mover></mrow></math></span> O2) between thermal treatments that were not attributable to differences in body size. Specifically, warm-acclimated gravid females showed significant reductions <span><math><mrow><mover><mi>V</mi><mo>˙</mo></mover></mrow></math></span> O<sub>2</sub> compared to cold-acclimated counterparts, exposing pronounced sexual dimorphism in mass-adjusted metabolic rates at higher test temperatures. In the second experiment, we expanded on our initial findings by directly testing the contribution of reproductive condition to observed sex differences in thermal acclimation capacity. By repeating the experiment of the early breeding season but including a third group of non-gravid females, we: (1) recapitulated our original finding – that gravid females exhibit a stronger response to thermal acclimation relative to males; and (2) showed that female thermal acclimation responses are absent in nongravid females, and therefore responses are contingent on reproductive condition. Taken together, our results provide a first glimpse into how sex and reproductive condition contribute to intraspecific variation in thermal acclimation capacity in an amphibian, and underscore the need for more hypothesis-driven studies to directly test when, where, and how such patterns arise.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104356"},"PeriodicalIF":2.9,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145774534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Short-term heat stress adaptation in intertidal oysters (Crassostrea sikamea): Integrative biochemical, transcriptomic and metabolomic insights 潮间带牡蛎的短期热应激适应：综合生化，转录组学和代谢组学见解

IF 2.9 2区生物学 Q2 BIOLOGY

Journal of thermal biology

Pub Date : 2025-12-11 DOI: 10.1016/j.jtherbio.2025.104355

Youli Liu , Yuanyuan Wang , Sheng Liu , Zhihua Lin , Qinggang Xue

Marine heatwaves threaten intertidal bivalves, including oysters, which can tolerate moderate temperature increases but are vulnerable to extreme thermal events. The ability to mount a rapid molecular and physiological response is crucial for surviving sudden environmental changes. However, the molecular mechanisms underlying the immediate response upon the initiation of temperature change, including transcriptional and metabolic processes remain poorly understood. This study employed an integrated approach to investigate the response of Kumamoto oysters to sublethal high temperatures. We conducted a survival assay, biochemical analyses, and transcriptomic and metabolomic profiling on gill tissues collected at intervals from 0.5 h up to the onset of shell gaping behavior (3–4 h). Despite exhibiting minimal mortality below 45 °C, the oysters showed a survival rate of only 14 % after 1-h exposure at 45 °C, with any temperature beyond this proving lethal (0 % survival). Biochemical analyses revealed that oxidative stress was elevated in all temperature stress treatments, but antioxidant activity was only significantly induced after exposure to 39 °C. Transcriptomic analysis identified 4442 heat shock responsive genes with functions in energy, immune, and antioxidant processes. Metabolomic assessments identified 420 differentially abundant metabolites, among which associated with glycolysis and fatty acid oxidation pathways were particularly notable. The ten most upregulated metabolites were amino acids and their derivatives, such as N-acetyl-L-glutamic acid, acetylvaline, and N-acetyl-leucine. Conversely, the ten downregulated metabolites primarily pertained to fatty acid metabolism, including 11β-Prostaglandin F2α and Carnitine. Integrative analysis of transcriptomic and metabolomic revealed links between gene and metabolite expression, particularly in pathways related to amino acid biosynthesis, cysteine and methionine metabolism, and galactose metabolism. This study identifies candidate genes and metabolites for future research on marine heatwave adaptation, elucidates adaptive strategies of oysters to temperature fluctuations, and provides valuable data for the future of oyster aquaculture amid global warming challenges.

海洋热浪威胁着潮间带双壳类动物，包括牡蛎，它们可以忍受适度的温度上升，但容易受到极端高温事件的影响。快速分子和生理反应的能力对于在突然的环境变化中生存是至关重要的。然而，在温度变化开始后的即时反应的分子机制，包括转录和代谢过程，仍然知之甚少。本研究采用综合方法研究熊本牡蛎对亚致死高温的反应。我们对鳃组织进行了生存分析、生化分析、转录组学和代谢组学分析，收集时间间隔为0.5 h，直到出现开壳行为（3-4小时）。尽管在45°C以下表现出最低的死亡率，但牡蛎在45°C下暴露1小时后的存活率仅为14%，高于此温度的任何温度都证明是致命的（0%存活率）。生化分析表明，在所有温度胁迫处理下，氧化应激均升高，但抗氧化活性仅在39℃处理后显著升高。转录组学分析鉴定了4442个热休克应答基因，这些基因在能量、免疫和抗氧化过程中起作用。代谢组学评估鉴定出420种差异丰富的代谢物，其中与糖酵解和脂肪酸氧化途径相关的代谢物尤为显著。上调最多的10种代谢物是氨基酸及其衍生物，如n -乙酰-l -谷氨酸、乙酰缬氨酸和n -乙酰-亮氨酸。相反，10种下调代谢物主要与脂肪酸代谢有关，包括11β-前列腺素F2α和肉毒碱。转录组学和代谢组学的综合分析揭示了基因和代谢物表达之间的联系，特别是在氨基酸生物合成、半胱氨酸和蛋氨酸代谢以及半乳糖代谢相关的途径中。本研究确定了未来海洋热浪适应研究的候选基因和代谢物，阐明了牡蛎对温度波动的适应策略，为未来全球变暖挑战下的牡蛎养殖提供了有价值的数据。

{"title":"Short-term heat stress adaptation in intertidal oysters (Crassostrea sikamea): Integrative biochemical, transcriptomic and metabolomic insights","authors":"Youli Liu , Yuanyuan Wang , Sheng Liu , Zhihua Lin , Qinggang Xue","doi":"10.1016/j.jtherbio.2025.104355","DOIUrl":"10.1016/j.jtherbio.2025.104355","url":null,"abstract":"<div><div>Marine heatwaves threaten intertidal bivalves, including oysters, which can tolerate moderate temperature increases but are vulnerable to extreme thermal events. The ability to mount a rapid molecular and physiological response is crucial for surviving sudden environmental changes. However, the molecular mechanisms underlying the immediate response upon the initiation of temperature change, including transcriptional and metabolic processes remain poorly understood. This study employed an integrated approach to investigate the response of Kumamoto oysters to sublethal high temperatures. We conducted a survival assay, biochemical analyses, and transcriptomic and metabolomic profiling on gill tissues collected at intervals from 0.5 h up to the onset of shell gaping behavior (3–4 h). Despite exhibiting minimal mortality below 45 °C, the oysters showed a survival rate of only 14 % after 1-h exposure at 45 °C, with any temperature beyond this proving lethal (0 % survival). Biochemical analyses revealed that oxidative stress was elevated in all temperature stress treatments, but antioxidant activity was only significantly induced after exposure to 39 °C. Transcriptomic analysis identified 4442 heat shock responsive genes with functions in energy, immune, and antioxidant processes. Metabolomic assessments identified 420 differentially abundant metabolites, among which associated with glycolysis and fatty acid oxidation pathways were particularly notable. The ten most upregulated metabolites were amino acids and their derivatives, such as N-acetyl-L-glutamic acid, acetylvaline, and N-acetyl-leucine. Conversely, the ten downregulated metabolites primarily pertained to fatty acid metabolism, including 11β-Prostaglandin F2α and Carnitine. Integrative analysis of transcriptomic and metabolomic revealed links between gene and metabolite expression, particularly in pathways related to amino acid biosynthesis, cysteine and methionine metabolism, and galactose metabolism. This study identifies candidate genes and metabolites for future research on marine heatwave adaptation, elucidates adaptive strategies of oysters to temperature fluctuations, and provides valuable data for the future of oyster aquaculture amid global warming challenges.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"135 ","pages":"Article 104355"},"PeriodicalIF":2.9,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145749977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0