Body Surface Temperature Research Articles

Effects of naked neck and frizzle genes on growth and egg-laying performance of chickens in the tropics in an era of climate change.

In regions characterized by tropical and subtropical climates, the elevated ambient temperatures exert adverse effects on both broiler and laying chickens, impacting their growth and egg production performance. To mitigate the challenges posed by heat stress, genetic strategies aimed at reducing feather coverage have gained prominence in hot climate areas. Among these approaches, the naked neck (Na) and frizzle (F) genes have emerged as particularly noteworthy. The Na and F genes play a pivotal role in facilitating heat dissipation and temperature regulation. By decreasing feather insulation, these genes enable efficient heat dissipation through exposed areas of the chickens' bodies. This reduction in feather coverage leads to elevated body surface temperature, which, in turn, enhances the capacity for heat loss and contributes to overall body temperature reduction. A substantial body of literature underscores the well-established positive impacts of the naked neck and frizzle genes on growth and egg-laying performance. As a result, these genes hold significant potential for integration into broiler and layer production systems, especially in regions characterized by high tropical temperatures. In the context of broiler farming under challenging heat conditions, the Na and F genes have demonstrated favorable effects on crucial parameters such as feed conversion ratio, body weight gain, disease resistance, and carcass attributes. Likewise, layers exposed to elevated temperatures exhibit enhanced egg production, eggshell quality, fertility, hatchability, and resistance to diseases when these genesare incorporated. Given that the prevalence of the naked neck and frizzle genes is primarily observed in indigenous chicken populations, it becomes imperative to prioritize measures for their conservation due to their exceptional performance in heat-stressed environments. To unlock the full genetic potential of exotic poultry reared in hot and humid conditions, the integration of the Na and F genes is a strongly recommended strategy.

Continuous Core Body Temperature Monitoring for Heatstroke Alert via a Wearable In-Ear Thermometer.

Heatstroke, a global concern exacerbated by climate change, poses significant health risks, potentially leading to multiorgan damage and fatalities. Core body temperature (CBT) is a critical and precise indicator of heatstroke, and its continuous monitoring could serve as a pivotal tool for early detection. Traditional CBT measurements, often invasive (e.g., surgical intubation, rectal or oral placement), and disrupt daily activities, whereas existing wearable devices predominantly measure skin temperatures which is susceptible to ambient environment, thus unreliable for heatstroke alert. To overcome these limitations, this study introduces an innovative in-ear wearable device to measure CBT via the cochlea, which allows for accurate CBT monitoring and timely heatstroke alerts during activities in high-temperature and high-humidity environments. The device comprises a negative temperature coefficient (NTC) thermometer integrated into a flexible precision circuit (FPC), a compact Bluetooth module, an 8 mA h micro battery, and a biocompatible, low-stimulus silica gel casing. With dimensions of 27 mm × 18 mm and a maximum in-ear diameter of 5 mm, weighing just 1.3 g, the device offers high portability and comfort, with a continuous operational lifespan of at least 24 h postcharging. A complementary software system facilitates continuous CBT monitoring, heatstroke alerts, and device management. Preliminary human trials demonstrate the device's accuracy in CBT measurement, rivaling that of rectal thermometry, and superior to the performance of surface body temperature measurement at different body parts. Long-term experiments affirm the device's efficacy in detecting rapid CBT escalations, enabling timely preventive measures against heatstroke.

Коррекция и усвоение данных гидрологических наблюдений температуры водных объектов

The paper proposes an algorithm for correcting the data of hydrological observations of water temperature and an algorithm for assimilating corrected data for calculations of water body surface temperatures in Russia. The temperatures are used in initial data for computing global medium-range weather forecasts with the new version of the SLAV10 model with a grid spacing of about 10 km. The correction algorithm for hydrological observations of water temperature makes it possible to eliminate ambiguity in temperature coding at most gauging stations. The assimilation of corrected hydrological observations allows reducing water body surface temperature errors in the SLAV10 model initial data as compared to specifying water temperature from the data of the nearest land points.

Clinical Applications, Legal Considerations and Implementation Challenges of Smartphone-Based Thermography: A Scoping Review.

Medical thermography is a non-invasive technique that allows the measurement of the temperature of the human body surface, exploiting the heat emitted by the body through the skin in the form of infrared electromagnetic radiation. Recently, smartphone-based thermography (ST) has drawn considerable attention. This scoping review (SR) aims to describe its current applications and reliability based on currently available research findings, also taking into account the medico-legal implications linked to its use. A search of the sources was conducted on multiple databases (PubMed, Scopus, Cochrane, Lilacs, Google Scholar). Based on a set of eligibility criteria, all articles deemed useful were included in the SR. Collected data, processed with descriptive statistics, are then discussed. From the initial 241 results, after duplicate removal and full-text reading based on inclusion/exclusion criteria, 20 articles were classified according to the main characteristics and indications and outcomes are highlighted based on clinical evidence. The most frequently documented fields of ST are wound care management and vascular surgery. Other disciplines are less explored (dentistry, ophthalmology, otorhinolaryngology, orthopedics, etc.). Practicality, operational simplicity and affordability of mobile thermographic devices are the chief strengths of this technology. Comparative studies with traditional thermal imaging methods are poor in terms of the number of patients analyzed but this technology showed high sensitivity and accuracy in the large number of patients enrolled in observational studies, encouraging the development of further operational protocols in all medical specialties. Gaining a deeper understanding of such techniques will also help settle the medico-legal issues which may arise from the clinical implementation of ST, thus appraising its reliability and safety from that perspective as well.

Investigation of phase change material based cool pack performance in vests for personalized thermal comfort in extremely hot climatic conditions: Model development and case studies

Vests with provisions for carrying multiple phase change material (PCM) based cool packs are one of the possible ways to provide personalized thermal comfort in extremely hot climatic conditions. Although this passive cooling mechanism is simple to implement, there are several challenges associated with the design of these heat packs. For instance, the heat packs must maintain the skin temperature within the comfortable range of 33±2Co (87.8-95 Fo) for the desired duration while also being as lightweight as possible. For the heat pack design, it is important to consider not only the hot climatic condition that causes heat to flow from ambient to body surface but also the heat generation from the body itself for different activity levels, such as reclining, standing, walking, jogging, running, and so on. In the present work, a numerical framework has been developed and experimental validation performed to investigate the performance of cool packs when it is loaded with any one of the following five PCMs, namely Ice, savE OM 21, Coconut oil, C18 paraffin, and Octadecane. The comparative performance of these cool packs is assessed based on the comfort duration for which they can maintain the body surface temperature within the specified range of 33±2Co. SavE OM21 PCM exhibited excellent performance in terms of providing thermal comfort more precisely. However, thermal conductivity must be enhanced from 0.14-0.21 W/mK to 1.0 W/mK. The lower masses of C18 paraffin and Octadecane PCM were deemed suitable for practical use in real-world scenarios.

Efficiency of infrared pyrometer and infrared thermography for assessing body surface temperature in hair sheep

The objectives of this study were: (i) to verify and compare the coat surface temperature (CST) of regions of interest (ROI) measured through infrared pyrometer (IRP) and thermography (IRT) under two environmental conditions, to evaluate (ii) reliability and (iii) sensitivity of the two infrared equipments to the environmental effect. Twenty hair ewes (Ovis aries), multiparous, non-lactating, non-pregnant, with body weight 59.38 ± 6.23 kg and body score condition ranging from 2.5 to 4.5 were evaluated. All CST, in both infrared methods, were higher (P < 0.001) in the afternoon (2 to 3 p.m.), with the exception of eyes surface temperature (TSEY) from IRT, which was higher (P < 0.001) in the morning (8 to 9 a.m.). Regarding the infrared methods at different times (twice a day, morning and afternoon), of the day, CST values for all ROIs were significantly higher (P < 0.001) in thermography, regardless of the time shift, except for ear pinna surface temperature (TSE) and rectum surface temperature (TSR), which showed no significant difference (P > 0.05) between the infrared methods during the morning shift. The thermal environment significantly influences (P < 0.001) the surface temperature of various anatomical regions in both infrared methods. The correlation coefficients between IRT and IRP were moderate. The IRT is more sensitive to the thermal environment, as it presented higher canonical coefficients in the environmental variables. Among surface temperatures, eye surface temperature is the most influenced by variables in the thermal environment, especially THI. All three methods (digital thermometer-DT, IRT and IRP) showed >80 % of the data variation in the first two components. Using the DT, we observed an association between vaginal temperature (VT) and RT with air temperature (AT) and temperature humidity index (THI), which was similar to the infrared thermography pattern, in which all ROIs were highly correlated with AT and THI. The opposite was observed in the pyrometer, in which an association between eye temperature and RH and lower factor loadings of the other ROIs with AT and THI in the first component was observed. In conclusion, while IRP and IRT showed similar performance in the morning, IRT proved to be more accurate in the afternoon, demonstrating a higher success rate in classifying the group of origin. Therefore, it is concluded that IRT is more reliable than IRP in detecting surface temperature changes under high temperatures.

Systematic Review and Meta-Analysis of Thermal Stress Assessment in Poultry Using Infrared Thermography in Specific Body Areas.

Thermal stress is a health and welfare concern in the poultry industry. Poultry have specific thermoregulation strategies for heat stress (i.e., vasodilatation) or cold stress (i.e., vasoconstriction). Infrared thermal (IRT) analysis is a non-invasive temperature assessment technology with significant benefits compared to conventional temperature measurements, which are invasive and time-consuming. However, a wide range of IRT methodologies and equipment are used for temperature assessment in poultry. The aim of this study was to perform a systematic review and meta-analysis of IRT applications in poultry undergoing thermal stress. The bibliographic search yielded 17 records for qualitative synthesis and 10 for quantitative analysis. The results showed IRT is more commonly studied during heat stress than cold stress, and more research is being conducted on laying hens than other poultry species. Also, four body areas (parts of the head, body, face, and leg) were identified as common areas of interest for body surface temperature measurement. There is a clear thermoregulation response to thermal stress in poultry, with marked differences between featherless and feather-covered areas. IRT in poultry undergoing thermal stress has a good diagnostic value and represents an important welfare assessment tool for future research, particularly when combined with other welfare assessment methods.

Evaluating the efficacy of probiotics and ascorbic acid as anti-stress agents against heat stress in broiler chickens.

Heat stress poses a substantial challenge to poultry production worldwide, highlighting the urgent need for effective management strategies. This study investigated the efficacy of probiotics (Saccharomyces cerevisiae) and ascorbic acid as antistress agents using cloacal and body surface temperatures (CT and BST) as heat stress biomarkers in broiler chickens. A total of 56 broiler chicks were used for the experiment and were divided into four distinct groups: control, probiotics (1 g/kg of feed), ascorbic acid (200 mg/kg of feed) and the combination of probiotics and ascorbic acid (1 g/kg and 200 mg/kg of feed, respectively). The study lasted 35 days; measurements were taken for ambient temperature (AT), CT, and BST. The ambient temperature in the pens consistently exceeded the thermoneutral zone (TNZ) established for broiler chickens. The CT values for broiler chickens in the probiotic group were significantly lower (p < 0.05) compared to the control group. Additionally, the BST values in the probiotic and probiotic + ascorbic acid groups were significantly lower (p < 0.05) than those in the control group. The findings suggest that incorporating probiotics, with or without ascorbic acid, can effectively reduce CT and BST values in broiler chickens thereby, enhancing thermoregulation when compared to the control group. This implies that using probiotics in poultry diets may enhance health and growth performance, potentially leading to better feed efficiency and reduced reliance on antibiotics. Implementing these dietary strategies could improve the productivity and welfare of broiler chickens in commercial settings.

A two-parameter Tikhonov regularization for a fractional sideways problem with two interior temperature measurements

This paper deals with a fractional sideways problem of determining the surface temperature of a heat body from two interior temperature measurements. Mathematically, it is formulated as a problem for the one-dimensional heat equation with Caputo fractional time derivative of order α∈(0,1], where the data are given at two interior points, namely x=x1 and x=x2, and the solution is determined for x∈(0,L),0<x1<x2≤L. The problem is challenging since it is severely ill-posed for x∉[x1,x2]. For the ill-posed problem, we apply the Tikhonov regularization method in Hilbert scales to construct stable approximation problems. Using the two-parameter Tikhonov regularization, we obtain the order optimal convergence estimates in Hilbert scales by using both a priori and a posteriori parameter choice strategies. Numerical experiments are presented to show the validity of the proposed method.

PRELIMINARY DATA ON COAT COVERAGE AND GROOMING INTERFERING WITH THE THERMAL COMFORT OF LHASA APSO AND SHIH TZU DOGS

The objective of this report was to investigate the effects of grooming on thermal comfort in Lhasa Apso and Shih Tzu dogs exposed to different ambient temperatures. A randomized block design in a 3 x 2 factorial scheme was used, with 3 different temperatures associated with whether the animal was groomed or not. Six adult dogs, consisting of two Lhasa Apsos and four Shih Tzus, were used. The dogs were exposed to temperatures of 17°C, 25°C, and 33°C both before and after grooming. Physiological parameters (blood pressure, heart rate, respiratory rate, rectal temperature, ambient temperature, ITU, and body surface temperature) were measured using infrared thermography with a portable IRT camera. The images were analyzed using FLIR Tools™ software with an emissivity of 0.97. Variance analysis was performed to evaluate the isolated effects and interactions between the factors of coat coverage and ambient temperature at the 5% significance level. No interaction was found between the treatments, nor were there isolated effects of the factors on the physiological parameters evaluated. A temperature of 33°C was associated with a higher rectal temperature (p&lt;0.05) in the animals. Ungroomed dogs exposed to temperatures of 25°C and 33°C had ITU values above the thermal comfort limit. In terms of body temperature, there was a significant interaction effect between coat coverage and the environment under different climatic conditions (p&lt;0.05). The surveyed grooming dogs exhibited greater body temperatures at all temperatures tested, namely, 17°C, 25°C, and 33°C. Grooming did not reduce the effects of thermal stress caused by different climatic conditions, indicating that grooming is not advisable for these animals

Thermal radiation imaging technology and sensor assisted calculation of sports training technology simulation

With the development of sports training science and technology, the real-time monitoring of athletes’ physical condition and training effect is becoming more and more important. As a non-contact measurement method, thermal radiation imaging technology can capture the changes of athletes’ body surface temperature efficiently and in real time, and provide relevant information about physiological state and performance indicators. This paper discusses the application of thermal radiation imaging technology in sports training to help measure athletes’ physical state and training effect, so as to provide scientific basis for improving training efficiency and reducing sports injuries. In this paper, the high resolution thermal imaging equipment is used to systematically analyze the thermal radiation imaging of athletes, and the physiological index monitoring and data processing technology are combined to dynamically observe the temperature distribution and change characteristics of athletes under different training states. Through comparative analysis, the correlation between the data provided by thermal radiation imaging technology in the training process and the traditional physiological indicators was evaluated. The results show that thermal radiation imaging technology can effectively reflect the heat distribution and local body temperature changes of athletes during training. Compared to traditional physiological feedback data, the technology has significant advantages in quickly identifying excessive fatigue and potential injuries in athletes, especially during high-intensity training, and can provide early warning of associated risks. The application of sensor-assisted measurement system will further enhance the accuracy and effectiveness of sports scientific research and provide important support for athletes’ scientific training and health management.

Adaptive capability of slow-growing backyard poultry as indicated by physiological and molecular responses in a hot and humid coastal climate

Assessing the adaptability of slow-growing rural chickens for improving thermotolerance to suit the global climate change is a major research need. This work was aimed to evaluate the adaptability of CARI-Debendra chickens and to identify the polymorphism as well as expression profiling of thermotolerant genes (HSP70 and GRP78) under prevailing temperature-humidity indices and thermal stress in a coastal environment. One hundred sixty straight run chicks were reared at THI≥75 (control) and THI>80 under coastal climate till 12 weeks. Polymorphism of HSP70 and GRP78 candidate genes were explored using restriction enzymes TaqI and HaeIII to identify possible thermotolerance markers. Expression profiling of both the genes in liver, intestine and pectoralis muscle was determined through quantitative real-time PCR. Rectal and body surface temperature recorded in the neck and back showed significant differences (P < 0.01) with higher temperature in THI>80 group. Comparatively lower live weights (P < 0.05) and poor FCR were recorded in THI>80 group. The villi height in all intestinal segments was significantly lower (P < 0.01), but deeper crypt depth was observed in THI>80 than control group. A lowest thymus weight (P < 0.05) was noted with no significant differences in immune response in treatment group. Serum levels of cholesterol, activities of lactate dehydrogenase, creatinine kinase and concentration of potassium, sodium and thyroxine hormone were not different between the 2 groups. The concentration of triiodothyronine and chloride ion was lower in THI>80 group indicating adaptive changes for thermoregulation. HSP70 gene expressions in the three tissues were differentially increased (P < 0.01) by temperature-humidity indices, but the expression of GRP78 was not different between the 2 groups. The results concluded that the environmental factors interact with genetics on adaptability towards thermotolerance in slow-growing chickens.

Thermal response in Boer goats differing in coat colour

Context The coat is the first defense layer protecting animals from direct sunlight, influencing radiant-heat absorption and loss. Dark coat colour may increase animal heat impact because of higher absorption of solar radiation. Aims We investigated the impact of pigmentation intensity on the heads of animals and their thermal responses to solar radiation. Furthermore, we compared the thermal responses between dark and light brown-coloured animals, to determine whether the duration of sun and shade exposure (3 h each) is sufficient to differentiate the heat gain and losses between the two groups. Methods The effect of coat colour on rectal and surface temperatures in Boer goats, classified according to their head pigmentation pattern as dark (DB, N = 11) or light brown (LB, N = 11), exposed to sun and shade, was evaluated. The animals’ body and head surface temperatures were measured the same day before, during, and after sun exposure by using infrared thermography. Individual thermographic images were analysed by body regions (rump, leg, neck) and head areas (eye, ear, upper and lower part of the head, and the muzzle). Key results During solar radiation, all measured variables increased. In the shade, the rump, leg, and neck surfaces remained elevated, whereas the head area cooled down faster, with the highest temperature changes measured for the ear of about 10%. Most surface cooling occurred within 30 min after returning to the shade. Coat colour groups differed only in higher overall muzzle temperature of DB than that of LB goats (P = 0.048). Correlations between rectal and surface temperatures were low to medium, ranging from −0.02 (eye) to 0.31 (muzzle). Conclusions The head area is suggested as the important thermal window for heat dissipation and selective brain cooling. Light brown-headed animals were more efficient in eliminating the heat gained from solar radiation when returned to shade. Implications The colouration of the animal’s head may play an important role for its heat tolerance. As an easy-to-recognise characteristic, coat colour can serve as a selection trait for local goat populations. In view of global warming, selection for lighter coat colour in domestic ruminants may also become important even under temperate climates.

Predictive models for heat stress assessment in Holstein dairy heifers using infrared thermography and machine learning.

Heat stress is a condition that impairs the animal's productive and reproductive performance, and can be monitored by physiological and environmental variables, including body surface temperature, through infrared thermography. The objective of this work is to develop computational models for classification of heat stress from respiratory rate variable in dairy cattle using infrared thermography. The database used for the construction of the models was obtained from 10 weaned heifers, housed in a climate chamber with temperature control, and submitted to thermal comfort and heat wave treatments. Physiological and environmental data were collected, as well as thermographic images. The machine learning modeling environment used was IBM Watson, IBM's cognitive computing services platform, which has several data processing and mining tools. Classifier models for heat stress were evaluated using the confusion matrix metrics and compared to the traditional method based on Temperature and Humidity Index. The best accuracy obtained for classification of the heat stress level was 86.8%, which is comparable to previous works. The authors conclude that it was possible to develop accurate and practical models for real-time monitoring of dairy cattle heat stress.

Mask R-CNN and Centroid Tracking Algorithm to Process UAV Based Thermal-RGB Video for Drylot Cattle Heat Stress Monitoring

This study developed and evaluated an algorithm for processing thermal-RGB video feeds captured by an unmanned aerial vehicle (UAV) to automate heat stress monitoring in cattle housed in the drylots. The body surface temperature (BST) of individual cows was used as an indicator of heat stress. UAV data were collected using RGB and thermal infrared imagers, respectively, at 2 and 6.67 cm per pixel spatial resolution in Spring 2023 (dataset-1) and Summer 2024 (dataset-2). Study sites were two commercial drylots in Washington State. The custom algorithms were developed to: (1) detect and localize individual cows using a Mask R-CNN-based instance segmentation model combined with centroid tracking; and (2) extract BST by averaging the thermal-imagery pixels for each of the segmented cows. The algorithm showed higher detection accuracy with RGB images as input (F1 score: 0.89) compared to thermal (F1 score: 0.64). BST extraction with combined RGB and thermal imaging approach required corrections for alignment problems associated with differences in optics, imaging field of view, resolution, and lens properties. Consequently, thermal imaging-only approach was adopted for assessing real-time cow localization and BST estimation. Operating at one frame per second, algorithm successfully detected 72.4% and 81.65% of total cows in video frames from dataset-1 (38 s) and -2 (48 s), respectively. The mean absolute difference between algorithm output and ground truth (BSTGT) was 2.1 °C (dataset-1) and 3.3 °C (dataset-2), demonstrating satisfactory performance. With further refinements, this approach could be a viable tool for real-time heat stress monitoring in large-scale drylot production systems.

143 Short- and long-term effects of heat stress in cow-calf pairs adapted to tropical and subtropical regions

Abstract Chronic exposure to high temperatures and humidity can limit beef cattle performance in tropical/subtropical environments, regardless of breed. Despite better heat adaptability compared with Bos taurus cattle, heat-stressed Bos indicus cattle also experience an increase in body temperature above the physiological limit. As body temperature increases, cascades of behavioral and physiological events are triggered to lessen heat load but often at the expense of productive outcomes. Contrary to other species and feedlot beef cattle, the effects of heat stress on physiology and performance of grazing cow-calf pairs have not been evaluated in detail, particularly for Bos indicus cattle. Preliminary data showed opposite outcomes to heat stress in Bos indicus vs. Bos taurus cattle, limiting the implications of the existing data generated from studies using beef and dairy Bos taurus cattle. This presentation will share some nutritional and management practices to mitigate heat stress in grazing beef cattle. Practices mentioned herein include altering the timing of body weight (BW) growth pattern (stair-step, SST) and immunomodulatory feed ingredient (IFI) supplementation for replacement beef heifers, and maternal access to shade to reduce heat load. For 100 d before the breeding season, Bos indicus-influenced beef heifers grazing warm-season grasses received a constant supplementation amount or SST strategy (50 d of low then 50 d of high supplementation), with or without IFI. Under severe heat stress conditions, IFI supplementation reduced heifer vaginal temperature but did not increase their growth and reproduction, whereas the SST strategy lowered internal body temperature, enhanced growth performance and pregnancy success compared with a conventional constant supplementation practice. Our group is also focused on the critical need to determine the specific effects of heat stress mitigation during pre- and postnatal phases on physiology and performance of Bos indicus-influenced cow-calf pairs. Study 1 evaluated the impacts of maternal access to artificial shade from 83 d prepartum until 50 d postpartum on body thermoregulation, performance, and physiology of beef heifers and their first offspring. Removing maternal access to shade led to greater maternal respiration rate, vaginal and body surface temperatures and reduced maternal body condition score and calf BW at birth. Nonetheless, offspring born from cows with no access to shade were remarkably heavier during a 60-d post-weaning period and had decreased plasma indicators of inflammation and positive effects to humoral immune response. Study 2 is a multi-year, USDA/NIFA-funded study designed to capitalize on the ability of cattle to reprogram physiological/immunological systems following exposure to stress during gestation. Study 2 combined gestational and postnatal heat abatement to enhance the overall growth/immune/reproductive performance of grazing Bos indicus-influenced cow-calf pairs. Partial data on long-term growth and reproductive performance, physiology, metabolome, and microbiome of both cows and their female offspring will be shared in this presentation.

Zero-shot image segmentation for monitoring thermal conditions of individual cage-free laying hens

Body temperature is a critical indicator of the health and productivity of egg-laying chickens and other domesticated animals. Recent advancements in thermography allow for precise surface temperature measurement without physical contact with animals, reducing animal stress from human handling. Gold standard temperature analysis via thermography requires manual selection of limited points for an object of interest, which could be time-consuming and inadequate for representing the comprehensive thermal profile of a chicken’s body. The objective of this study was to leverage and optimize a zero-shot artificial intelligence technology for the automatic segmentation of individual cage-free laying hens within thermal images, providing insights into their overall thermal conditions. A zero-shot image segmentation model (Segment Anything, “SAM”) was modified by replacing manual selections of target points with automatic selection of the initial point using pre-processing techniques (e.g., thresholding) in each thermal image. The model was also incorporated with post-processing techniques integrated with a machine learning classifier to improve segmentation accuracy. Three versions of modified SAM models (i.e., SAM, FastSAM, and MobileSAM), two common instance segmentation algorithms (i.e., YOLOv8 and Mask R-CNN), and two foundation segmentation models (i.e., U2-Net and ISNet) were comparatively evaluated to determine the optimal one for bird segmentation from thermal images. A total of 1,917 thermal images were collected from cage-free laying hens (Hy-Line W-36) at 77–80 weeks of age. The image dataset exhibited considerable variations such as feathers, bird movement, body gestures, and the specific conditions of cage-free facilities. The experimental results demonstrate that the modified SAM did not only surpass the six zero-shot models—YOLOv8, Mask R-CNN, FastSAM, MobileSAM, U2Net, and ISNet—but also outperformed other modified SAM-based models (Modified FastSAM and Modified MobileSAM) in terms of hen detection performance, achieving a success rate of 84.4 %, and in segmentation performance, with an intersection over union of 85.5 %, recall of 91.0 %, and an F1 score of 92.3 %. The optimal model, modified SAM, was pipelined to extract statistics including the averages (°C) of mean (27.03, 27.04, 28.53, 26.68), median (26.27, 26.84, 28.28, 26.78), 25th percentile (25.33, 25.61, 27.26, 25.53), and 75th percentile (28.04, 27.95, 29.22, 27.55) of surface body temperature of individual laying hens in thermal images for each week. More statistics of hen body surface temperature can be extracted based on the segmentation results. The developed pipeline is a useful tool for automatically evaluating the thermal conditions of individual birds.

The back body temperatures of patients with idiopathic scoliosis measured through exercise.

Aerobic exercise is closely associated with the vital functions of patients with scoliosis. Infrared thermography (IRT) has been increasingly applied in physiological measurements in recent years. This observational study aimed to use IRT to examine the back body surface temperatures of patients with idiopathic scoliosis during aerobic exercise. Forty-two participants who completed a pre-test were divided into a scoliotic group and a non-scoliotic group. Both groups completed a 30-minute cycling exercise, during which their back body temperature was measured using IRT, and the root-mean-square of the back electromyography value after 30minutes of aerobic exercise was analyzed. The back body temperature decreased significantly after 30minutes of exercise in the non-scoliotic group. In contrast, the back body temperature (at the trapezius and quadratus lumborum muscles) was asymmetric or increased after exercise in the scoliotic group. These findings suggest that when patients with scoliosis exercise, their back body temperature should be assessed thoroughly to prevent adverse physiological reactions potentially caused by back body temperature imbalances as well as the potential health problems caused by poor heat dissipation. In addition, such observations can be useful in the early screening of scoliosis.

Profiling the dynamic variations in body and scrotal surface temperatures of goats reared under stressful conditions using infrared thermography: Analytical perspectives

Infrared thermography (IRT) is an essential non-invasive method for analyzing surface temperature variations in animals, offering valuable insights into livestock stress responses. Despite their resilience, goats can face significant challenges under extreme conditions like heat-stress and water deprivation. This experiment aimed to delineate the dynamic variations in whole-body and scrotal surface temperatures in goats subjected to the combined impact of both conditions using IRT. Eight healthy Aardi bucks were exposed to three 72-h treatments: euhydration, dehydration, and rehydration. Continuous meteorological monitoring provided ambient-temperature, relative-humidity, and temperature-humidity index (THI) values. Surface temperatures were measured twice daily at 08:00 and 15:00, and thermal gradients between ambient and body or scrotal surface temperatures were computed. Based on the obtained mean THI values, the bucks experienced heat-stress throughout the experiment. Additionally, results revealed noticeable variations in both surface temperatures across treatments and time points, indicated by measures of central tendency, variability, shape descriptors, and frequency distribution of temperature. Morning measurements indicated lower temperatures and gradients under euhydration, while water deprivation led to higher temperatures and compromised thermal regulation. Conversely, afternoon data showed higher variability in temperature responses, highlighting the compounded effect of diurnal heat-stress and water deprivation. Although water-restoration mitigated some effects of deprivation, it did not fully restore thermal homeostasis to euhydrated levels. Thermal gradients further emphasized the goats' dynamic thermoregulatory mechanisms, which were compromised under water deprivation, particularly in the scrotal region, but were partially restored upon restoration. These findings demonstrate the effectiveness of IRT in assessing thermal responses in goats and underscore the importance of adequate hydration for maintaining thermal balance under heat-stress. The herein performed profiling provides valuable insights with implications for overall health, reproductive efficiency, productivity, and welfare in heat-stressed and water-deprived goats, which might offer a framework for future research on livestock adaptation to such challenging environmental conditions.

Enhancing stress assessment in sledge reindeer (Rangifer tarandus): a pilot study on infrared thermal imaging and its opportunities for advancement as a welfare assessment tool

Measuring immediate physiological stress responses in animals can be challenging; saliva and blood sampling, while invasive, may also generate confounding stress responses, and equipping animals with heart rate sensors is not always feasible. Nevertheless, emerging technologies offer a non-invasive and contactless method to measure additional body surface temperature changes induced by acute stress, using infrared thermal measurement of the eye caruncle region. Contactless temperature measurement has the potential to assess the emotional state of animals affected by human physical contact. Reindeer, being highly sensitive to touch and naturally avoiding physical contact, exemplify this case. With growing interest in safari tours involving sledging reindeer, there is a need to investigate how these animals are affected by human interactions and how they adapt to daily close contact. In this pilot experiment, we evaluated the efficacy of thermal imaging in measuring medial canthus temperature fluctuations in non-habituated sledging reindeer while being petted by unfamiliar humans. Our findings support the hypothesis that medial canthus temperature significantly decreases during petting and increases once the interaction ceases, aligning with established stress response patterns found in the literature. This pilot experiment underscores the potential of infrared thermal imaging for non-invasively monitoring physiological responses to stress in tamed reindeer. Moreover, it sets the foundation for refining methodologies and experimental designs using infrared thermal imaging in animal welfare research.