Thermotolerant Capacity of Diverse Indonesian Lowland Holstein's Black and White Skin-Pigmentation Intensity

During a simulated haemorrhagic challenge, syncopal symptoms develop sooner when individuals are hyperthermic relative to normothermic. This is due, in part, to a large displacement of blood to the cutaneous circulation during hyperthermia, coupled with inadequate cutaneous vasoconstriction during the hypotensive challenge. The influence of local skin temperature on these cutaneous vasoconstrictor responses is unclear. This project tested the hypothesis that local skin temperature modulates cutaneous vasoconstriction during simulated haemorrhage in hyperthermic humans. Eight healthy participants (four men and four women; 32 ± 7 years old; 75.2 ± 10.8 kg) underwent lower-body negative pressure to presyncope while heat stressed via a water-perfused suit sufficiently to increase core temperature by 1.2 ± 0.2 °C. At forearm skin sites distal to the water-perfused suit, local skin temperature was either 35.2 ± 0.6 (mild heating) or 38.2 ± 0.2 °C (moderate heating) throughout heat stress and lower-body negative pressure, and remained at these temperatures until presyncope. The reduction in cutaneous vascular conductance during the final 90 s of lower-body negative pressure, relative to heat-stress baseline, was greatest at the mildly heated site (-10 ± 15% reduction) relative to the moderately heated site (-2 ± 12%; P = 0.05 for the magnitude of the reduction in cutaneous vascular conductance between sites), because vasoconstriction at the moderately heated site was either absent or negligible. In hyperthermic individuals, the extent of cutaneous vasoconstriction during a simulated haemorrhage can be modulated by local skin temperature. In situations where skin temperature is at least 38 °C, as is the case in soldiers operating in warm climatic conditions, a haemorrhagic insult is unlikely to be accompanied by cutaneous vasoconstriction.

The purpose of this research was to determine the effect of heat stress on thermoregulation, haematology, and productivity of Holstein Friesian (HF) dairy cows raised in different elevations. A total of 63 HF in a normal lactation period were used in this study. The research was conducted for 3 months during dry season in three different areas, which were at Pondok Ranggon (97 m.a.s.l) which categorized as a lowland, Ciawi (576 m.a.s.l) which categorized as a lower-upland, and Lembang (1241 m.a.s.l) which categorized as an upland. Observation on microclimate aspects which includes environmental temperature (Ta), relative humidity (RH) and Temperature-Humidity Index (THI) was done by recording each variable for every 2 hours starting from 08.00 to 16.00 WIB. The thermoregulation analysis was done based on the given physiological responses which consisted of the skin temperature (Ts), rectal temperature (Tr), body temperature (Tb), heart rate (Hr), respiratory rate (Rr), Heat Tolerance Coefficient (HTC), plasma cortisol level and haematological profile observation. The Ta, Rr, and THI measurements showed that in the lowland and lower-upland, the HF experienced moderate heat stress, while the HF raised in the upland area experienced less heat stress. The results showed that the dairy cows which raised in lowland had the highest HTC, Tr, Ts and Tb (P<0.05) and lowest Hr (P<0.05). All of the physiological and haematological parameters in the three study area showed a normal value.Furthermore, the erythrocyte, Hb and PVC concentration in a lowland raised HF were higher (P<0.05), while the plasma cortisol levels were not significantly different. The milk production of the observed dairy cows in different elevations was significantly different (P<0.05), with the highest milk yields, were found in the upland raised HF (13.1±3.52 kg), followed by the lower-upland (11.3±4.73 kg) and lowland (7.0±3.36 kg). In general, all of the HF raised in different land elevations was exposed to heat stress during dry seasons, even though the cows showed the ability to physiologically adapt and cope with the conditions.

This study investigated the heat stress response in Holstein Friesian and Sahiwal cattle by examining DNA methylation markers in the HSP70 gene promoter. Heat stress parameters such as temperature-humidity index (THI), average rectal temperature (ART), and heat tolerance coefficient (HTC) were analyzed alongside mRNA production during summer and winter. Blood samples were collected from both Holstein Friesian and Sahiwal cattle breeds to assess heat stress parameters, including THI, ART, and HTC. Seasonal variations in these heat stress parameters were evaluated along with mRNA expression levels. The DNA methylation pattern in the HSP70 gene promoter was assessed using the AvaI enzyme while gene expression was analyzed via quantitative PCR with PPIA as a control. Significant correlations were found between seasons, breed-specific heat stress parameters, HSP70 expression, and DNA methylation. Both Sahiwal and Holstein Friesian cattle exhibited higher HTC when DNA methylation was absent, with Sahiwal cattle consistently demonstrating greater heat tolerance than Holstein Friesians. This study highlights the complex interplay between seasonal changes, breed-specific adaptations, and epigenetic modifications in cattle's heat stress responses. The upregulated HSP70 expression suggests a role in thermotolerance. However, the study focused on a single DNA methylation change; broader investigations into additional epigenetic modifications are needed to fully understand heat stress resilience mechanisms across cattle populations.

Water buffaloes are recognized for tolerating heat but are still susceptible to heat stress. This study aims to determine whether water buffalo farms are subjected to stressful environmental conditions and to assess the animals’ biological responses to heat stress. Additionally, it explains how these animals adapt to specific ecological conditions. Temperature and relative humidity were measured during summer, and the temperature-humidity index (THI) was calculated. Biological parameters such as rectal temperature, pulse, and respiratory rate were recorded. Adaptability was assessed using the heat tolerance coefficient (HTC), along with the expression of the HSP70 gene as a biomarker for heat stress and thermotolerance. The study revealed moderate to severe heat stress in the farms, indicated by THI>85, and all recorded animal responses were above normal levels. Some animals were drooling, breathing heavily, and panting. Although experiencing heat stress, frequent and prolonged exposure allowed adaptability, as indicated by an HTC>90, and elevated levels of HSP70 gene expression for its protective mechanisms. Interventions like using fans and misters and providing more drinking water helped improve conditions. In conclusion, while water buffaloes experience heat stress, they can develop thermotolerance and adaptability over time. Information © The Authors 2025

Heat shock proteins act as molecular chaperones that have preferentially been transcribed in response to severe perturbations of the cellular homeostasis such as heat stress. Here the traits respiration rate (RR), rectal temperature (RT), pack cell volume (PCV) and the individual heat tolerance coefficient (HTC) were recorded as physiological responses on heat stress (environmental temperatures) in Bos taurus (crossbred Holstein Friesian; HF) and B. indicus (Thai native cattle: White Lamphun; WL and Mountain cattle; MT) animals (n = 47) in Thailand. Polymorphisms of the heat shock protein 90-kDa beta gene (HSP90AB1) were evaluated by comparative sequencing. Nine single nucleotide polymorphisms (SNP) were identified, i.e. three in exons 10 and 11, five in introns 8, 9, 10 and 11, and one in the 3′UTR. The exon 11 SNP g.5082C>T led to a missense mutation (alanine to valine). During the period of extreme heat (in the afternoon) RR and RT were elevated in each of the three breeds, whereas the PCV decreased. Mountain cattle and White Lamphun heifers recorded significantly better physiologic parameters (p < 0.05) in all traits considered, including or particularly HTC than Holstein Friesian heifers. The association analysis revealed that the T allele at SNP g.4338T>C within intron 3 improved the heat tolerance (p < 0.05). Allele T was exclusively found in White Lamphun animals and to 84% in Mountain cattle. Holstein Friesian heifers revealed an allele frequency of only 18%. Polymorphisms within HSP90AB1 were not causative for the physiological responses; however, we propose that they should at least be used as genetic markers to select appropriate breeds for hot climates.

Heat shock proteins (HSPs) are expressed in response to heat stress, and the polymorphism in HSP genes at single-nucleotide level has been reported to be associated with heat tolerance and production performance traits in cattle. HSPB8 gene has been mapped on Bos taurus autosome 17 (BTA-17) spanning nearly 13,252 bp and comprising three exons and two introns. The present study was conducted in Sahiwal cows (n = 108) reared in subtropical climate with the objectives to identify SNPs in all three exons and part of intron 1 of HSPB8 gene and to analyze their association with heat tolerance traits in Sahiwal cows. Respiration rate (RR) and rectal temperature (RT) were recorded once during probable extreme hours in different seasons or Temperature-Humidity Index (THI), i.e., winter, spring, and summer. Heat tolerance coefficient (HTC) was also calculated to check the adaptability of the animals during the period of heat stress. The comparative sequence analysis revealed a total two single-nucleotide polymorphisms (SNPs), i.e., g.507G>A in exon 1 and g.881T>C in intron 1 of HSPB8 gene. Out of these two identified SNPs, only one SNP, i.e., g.507G>A, was found to be significantly associated with heat tolerance indicator traits (RR, RT, and HTC) in Sahiwal cows. The perusal of results across different seasons showed the significant (P < 0.01) difference in RR, RT, and HTC between winter, spring, and summer seasons. RR, RT, and HTC were found to be significantly lower (P < 0.01) in GA as compared to GG genotype of g.507G>A SNP of HSPB8 gene. However, in case of another SNP, i.e., g.881T>C, located on intron 1, the RR, RT, and HTC were having non-significant association with the different genotypes, i.e., TT and TC. These findings may partly suggest that GA genotype of SNP g.507G>A of HSPB8 gene has a probable role in heat tolerance in Sahiwal cattle and can therefore be utilized as a marker in propagation of thermo-tolerance cattle in hot tropical and subtropical climate. Nevertheless, the involvement of other regulatory mechanisms cannot be overruled.

Heat shock protein (HSP) 90 gene provides protection and adaptation to thermal assault and certain polymorphisms have been associated to heat tolerance in humans and animals. Single nucleotide polymorphisms (SNPs) of HSP 90 gene were used to evaluate the scientific basis of heat tolerance in four zebu breeds of Nigeria. The DNA was extracted from skin tissue of 90 adult bulls representing White Fulani (WF), Sokoto Gudali (SG), Red Bororo (RB), and Ambala (AM). The SNPs were determined in DNAs using PCR, sequencing, and visualization and bio-editing by chromatogram in SeqMan Ngen tool. Subsequently, respective genotypes were constructed and genotypic and allelic frequencies were computed. Also, body parameters related to heat stress (HS) including body temperature (BT), rectal temperature (RT), and respiratory rates (RR) were taken for each animal before biological sampling and heat tolerance coefficient (HTC) was calculated. We detected four SNPs distinct/specific for each breed as follows: change from thymine (T) to guanine (G) at position 116 (T116G) in RB, G to cytosine (C) at 220 (G220C) in SG, G to adenine (A) at two positions, 346 (G346A) and 390 (G390A) in AM and WF, respectively. Heterozygous SNPs showed significantly lower values (P < 0.0001) for BT, RT, RR, and HTC than homozygous genotypes at all positions. We hypothesize that animals with heterozygous SNPs in exon 3 of HSP 90 may be tolerant to HS. These SNPs can be used as bio-markers for screening large populations of cattle for tolerance to hot tropical conditions in Nigeria and other sub-humid places.

Efficacy and safety of ritlecitinib (an oral JAK3/TEC family kinase inhibitor) were evaluated in patients with nonsegmental vitiligo (NSV) across Fitzpatrick skin types (FSTs). Patients with FST I-III ('light skin'; n = 247) and FST IV-VI ('dark skin'; n = 117) received once-daily ritlecitinib 50 mg (with/without 4-week loading dose), low-dose ritlecitinib or placebo for 24 weeks. At baseline, patients with light skin displayed higher CLM-1 and NCR1 serum levels than patients with dark skin (p < 0.05). At 24 weeks, ritlecitinib 50 mg improved the extent of depigmentation measured by percent change from baseline in facial-vitiligo area scoring index (placebo-adjusted mean difference [90% CI]) in patients with light (-15.2 [-24.7, -5.8]; p = 0.004) and dark (-37.4 [-50.3, -24.4]; p < 0.0001) skin, with continuous re-pigmentation through week 48. Treatment-emergent adverse events were similar across FSTs. At weeks 4 and 24, ritlecitinib 50 mg reduced CXCL11 serum levels (p < 0.001) in patients with light skin, whereas patients with dark skin had increased levels at week 4 (p = 0.05) and no significant change at week 24. Ritlecitinib 50 mg decreased IL-9 and IL-22 expression levels in dark skin compared with light skin (qPCR; p < 0.05). These differences in immune dysregulations may explain why NSV patients with dark skin respond to therapy earlier than patients with light skin.

To investigate the effect of therapeutic infrared class 3B laser irradiation on skin temperature in healthy participants of differing skin color, age, and gender. Little is known about the potential thermal effects of Low Level Laser Therapy (LLLT) irradiation on human skin. Skin temperature was measured in 40 healthy volunteers with a thermographic camera at laser irradiated and control (non-irradiated) areas on the skin. Six irradiation doses (2-12 J) were delivered from a 200 mW, 810 nm laser and a 60 mW, 904 nm laser, respectively. Thermal effects of therapeutic LLLT using doses recommended in the World Association for Laser Therapy (WALT) guidelines were insignificant; below 1.5°C in light, medium, and dark skin. When higher irradiation doses were used, the 60 mW, 904 nm laser produced significantly (p < 0.01) higher temperatures in dark skin (5.7, SD ± 1.8°C at 12 J) than in light skin, although no participants requested termination of LLLT. However, irradiation with a 200 mW, 810 nm laser induced three to six times more heat in dark skin than in the other skin color groups. Eight of 13 participants with dark skin asked for LLLT to be stopped because of uncomfortable heating. The maximal increase in skin temperature was 22.3°C. The thermal effects of LLLT at doses recommended by WALT-guidelines for musculoskeletal and inflammatory conditions are negligible (<1.5°C) in light, medium, and dark skin. However, higher LLLT doses delivered with a strong 3B laser (200 mW) are capable of increasing skin temperature significantly and these photothermal effects may exceed the thermal pain threshold for humans with dark skin color.

Developing heat tolerant rice varieties is imperative for safeguarding global food security against climate change. This study establishes the heat shock protein HSP70 as a key molecular biomarker for heat tolerance by linking its expression dynamics to physiological and agronomic resilience. We evaluated four rice cultivars under heat stress (40 ± 2 °C) by analyzing relative membrane permeability (RMP), hydrogen peroxide (H2O2), and malondialdehyde (MDA) to assess membrane thermostability and oxidative damage, alongside spikelet fertility as a yield component. A novel, integrative metric the Heat Tolerance Coefficient (HTC) was developed to quantify resilience based on fertility retention under stress. Our results revealed profound genotypic variation. The heat tolerant cultivars (K-95, IR-6) exhibited robust, early induction of HSP70, which correlated strongly with superior membrane stability (RMP < 35%), minimal oxidative damage (H2O2 ~ 30–34 µM/g FW; MDA ≤ 0.6 µM/g FW), and high spikelet fertility retention (82%), resulting in a high HTC (up to 91). In contrast, sensitive cultivars (DR-92, DR-83) showed delayed HSP70 expression, culminating in severe membrane damage (RMP >64%), significant oxidative stress, and a drastic decline in fertility (to 60%), reflected by a low HTC (as low as 65). The HTC effectively integrates molecular, physiological, and agronomic data into a single powerful index for selection. We conclude that early and sustained HSP70 expression is a hallmark of heat tolerance and propose that the HTC provides a robust, practical framework for accelerating the breeding of climate-resilient rice.

This research was conducted to study heat tolerance (HT) of three breed cattle of Simmental Crossbred, Ongole Crossbred and Pesisir Cattle. The animals were reared semi extensively by farmers in low land area of Pariaman, Pesisir districts and Padang city of West Sumatra. Sixty-four cows consisting of 14 Simental crossbred, 25 Ongole crossbred and 25 Pesisir bred was used in this study. Each animal was measured for skin and rectum temperature, rate of respiration and heart. Body temperature and heat tolerance coefficient (HTC) were then calculated by using the measured data. Results showed that Pesisir bred was found the highest HTC (95.86), followed by Simental crossbred (92.94) and Ongole crossed bred (87.54).

Background: It has been demonstrated that the composition of HSP70 heat shock protein 70 is temperature correlated HSP70 effects is one as cellular thermometer in response to heat stress and other stimuli. Goat also possess anatomical and physiological characteristics that qualify for their wide ability to ecological adaptability, nevertheless, the productivity of the individual declines during thermal stress .the study in the issuance of this article accomplished to analyze the level of concentration of heat shock protein variance heat stress phenotypes in response to chronic heat stress. Ruslt: The investigation has been carried out in Alpin (brown colour), Saanen (Wightcolour), these breeds same age (1-2 year) and differ in size and production performance. The thermostress appreciation was at a temperature humidity index (THI) 80.8 during summer, 55.1 during winter and 70.1 during spring. Physiological parameters for thermal stress susceptibility was carried at by combining pulse rate (PR) (bpm), respiration rate (RR) (breath/min), body temperature (BT) °C, skin temperature (ST) °C and head temperature (HT). HSP70 level of concentrations were analyzed with ELISA, the gene expression pattern of HSP70 in different seasons indicated that the HSP70 for Saanen breed was 26.9, 18.3 and 14.1 during spring, summer and winter respectively. HSP70 for Alpine was 12.7, 13.7 and 14.7 in the spring, summer and winter respectively. Conclusion: The seasonal variation associated with changes of environmental variable, especially ambient temperature had great effects on physiological and cellular function of goats. Under adverse climatic conditions the body and skin temperature of goats increased due to the heat loading into the animal body. To maintain the homeothermy, goats increased their respiratory frequency to promote heat dissipation. Moreover, goats’ body develop a cellular pathway to cope thermal challenge. This later is expressed through the high synthesis of heat shock protein that was observed in this study. HSPs represents an important molecular indicator when assessing heat stress in goats.

Mechanisms of thermal dysregulation in primary hyperhidrosis and hypohidrosis.

The present investigation entitled “Evaluation of Phule Amrutkal mobile application for estimation of Temperature Humidity Index (THI) in cattle” was conducted at Indigenous Cattle Research cum Training Centre, Division of Animal Husbandry and Dairy Science, College of Agriculture, Pune to assess the correlation between THI values and physiological responses of animals. Thirty clinically healthy cattle, comprising animals of Indigenous and Crossbreed, maintained under uniform feeding and management conditions, were monitored across summer, monsoon, and winter seasons. Open-source data was obtained by Mobile application “Phule Amrutkal”. Physiological responses demonstrated breed-specific variation. Indigenous cattle exhibited stable morning respiration rates (RR 17-21 breaths/min) with weak or negative THI correlations (r=-0.17 to 0.15), reflecting greater thermotolerance. Crossbreeds, however, showed stronger positive correlations (morning r=0.33-0.57, afternoon r=0.82) with elevated RR (up to 43.33 breaths/min in summer), indicating higher sensitivity to thermal load. Rectal temperature (RT) and pulse rate (PR) correlated moderately with THI in crossbreds during mornings, but weaker in afternoons due to adaptive thermoregulation. Non-invasive indicators such as muzzle temperature (MT) and skin temperature (ST) displayed strong afternoon correlations with THI (r=0.67-0.71), confirming their reliability in field assessment. In afternoon Body temperature (BT) showed consistently strong associations (Indigenous r=0.40, Crossbreed r=0.50), establishing it as a robust heat stress biomarker. Pulse rate (PR) and rectal temp (RT) showed less sensitivity while Respiration rate (RR), Ear temp (ET), Muzzle temp (MT), Body temp (BT), Skin temp (ST) showed greater sensitivity and more fluctuations. Indigenous cattle showed better adaptability than crossbred cattle.Seasonal analysis revealed that summer (March-May) imposed the highest thermal stress, with crossbreds recording peak physiological strain. Monsoon reduced heat load due to rainfall, but humidity stress persisted. Post-monsoon and late winter showed residual or diurnal heat stress effects, particularly in crossbreds. Overall, indigenous cattle demonstrated superior heat resilience, while crossbreds were more vulnerable, with THI derived from IMD and sensors proving more reliable for assessing diurnal stress dynamics.The THI values derived from the Phule Amrutkal mobile application provide reliable estimates of actual temperature and humidity, thereby enabling accurate calculation of THI. These accurate estimations are instrumental in adopting timely adaptive measures to mitigate the impact of heat stress in livestock management.

Human sweating regulation at rest, evaluating thermal inputs effects on thermoregulatory center and internal hypothalamic and skin temperatures