Correlation between Ocular and Rectal Temperature with Intra Ocular Pressure in Horse during Exercise

Dynamic Adaptation of Hematological Parameters, Albumin, and Non-Esterified Fatty Acids in Saddlebred and Standardbred Horses During Exercise

The response to exercise following a rest period may vary among horse breeds based on the importance of the hematological and hematochemical profiles of athletic horses. Ten Standardbred and ten Italian Saddlebred mares were subjected to a 4-week training program after a seasonal rest, and hematological parameters (red blood cells-RBCs; hemoglobin-Hb; hematocrit-Hct; platelets-PLTs; platelet aggregation-AG; aggregation slope-Slope; fibrinogen-Fb), as well as Albumin (Alb) and non-esterified fatty acids (NEFAs), were analyzed. Blood samples were obtained each week during the training program following a simulated exercise performed at T0 and T4 (T0pre-T0post; T1, T2, T3, and T4pre-T4post). A two-way ANOVA revealed an increase in all assessed parameters post vs. pre at T0 and T4 (p < 0.01) and a decrease in PLTs (p < 0.01) at T0 and T4 in both breeds. A significant effect of breed was observed, with higher values for RBCs and Hb at each time point (p < 0.001); Hct at T0 post, T2, T3, and T4 post; and NEFAs (p < 0.001) at T0 post and T4 post in Standardbred compared to Saddlebred horses. Positive correlations were identified among RBCs, Hb, Hct, PLTs, Alb, and NEFAs in both breeds and between AG and Slope in Saddlebred horses. Negative correlations were identified among AG and RBCs, Hb, Hct, PLTs, Alb, and NEFAs in Standardbred horses and for AG and Slope with RBCs, Hb, Hct, and PLTs in Saddlebred horses. A comparable reaction to training was observed in both breeds following the seasonal rest.

Climate change impact on blood haemogram in the horse: a three-year preliminary study

Introduction

The global climatic changes pose a substantial threat to the well-being and productivity of both humans and animals.

Methods

This study examined the impact of climate changes during different seasons over a 3-year monitoring period (2021-2023) on various blood parameters including, white blood cells (WBC), neutrophils, basophils, eosinophils, lymphocytes, and monocytes, hematocrit (HCT), hemoglobin (HGB), red blood cells (RBC), platelets (PLT), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH). The study focused on 25 Thoroughbred mares located in Kastamonu-Türkiye. Thermal and hygrometric parameters, including ambient temperature, relative humidity, and ventilation, were collected. Subsequently, Temperature-Humidity index (THI) was computed. Blood samples were collected on the first day of every month from January 2021 to December 2023 and used for a complete blood count analysis. Between 2021 and 2023, changes in environmental indicators were correlated to changes in hematological parameters.

Results

Two-way for repeated measures ANOVA revealed a significant seasonal fluctuation (<0.0001) in ambient temperature, relative humidity, and THI. There was a reduction in RBC (<0.01), and MCH (<0.01) every year, HGB (<0.0001) in summer 2021, 2022 and in summer and autumn 2023. HCT (<0.0001), MCV (<0.01), showed decreasing values in autumn 2022 and 2023. MCHC values showed increasing values in July and August 2021, 2022 and in June 2023. WBC levels increased throughout the spring periods of 2021 and 2022. In April 2021, there were elevated levels of lymphocytes and monocytes (<0.0001) respectively.

Discussion

These findings could be helpful to promote the monitoring of physiological status both for the assessment of welfare status and for diagnostic purposes for the evaluation of possible disease outbreaks due to climate change in veterinary medicine.

Using infrared thermography for the evaluation of road transport thermal homeostasis in athletic horse

This study aimed to evaluate changes in body temperature in athletic horses during two different road transport distances. Six Italian Saddle horses were subjected to a 100 and 300 km transport during different times of day (am and pm). Rectal and cutaneous temperatures were recorded before (T0), immediately (following 5 min- T1) and 1 hour (T2) after transport by means of a rectal digital thermometer and a thermal infrared camera (FLIR T440) respectively, for the evaluation of left and right side of four body regions: jugular, shoulder, croup and inner thigh. There were no differences between left and right sides, inner thigh or rectal temperatures when comparing the transport distance, time points or time of day. At T0, jugular (P < 0.0001), shoulder (P < 0.01) and croup (P < 0.01) average temperatures were higher in the pm compared to those in the am in both journeys. At T1, jugular (P < 0.01) and croup (P < 0.01) temperatures were lower in the pm compared to am following the 300 km journey. Jugular temperature (P < 0.0001) was higher following the 300 km compared to the 100 km journey at each time point (T1 and T2) at both times of day (am and pm). Shoulder (P < 0.0001) and croup temperatures (P < 0.0001) were higher at T2 after the 300 km journey than at T2 after the 100 km journey). The current results suggested a difference between the two distances and the time of day appeared to have as great effect on ocular temperature as road transport distance.

Eye Temperature Measured with Infrared Thermography to Assess Stress Responses to Road Transport in Horses

The aim of the present study was to investigate eye temperature modifications after road transport in athletic horses habituated to travel. Eight adult Italian saddle horses traveled 100 km and, two weeks later, 300 km. Eye temperature (ET), rectal temperature (RT) and serum cortisol concentration were assessed before (T1), after (T2) and 60 min (T3) after the road transport. ET was evaluated with infrared thermography (IRT) in three regions of interest: EL1 (medial canthus), EL2 (central cornea) and EL3 (lateral canthus). Two-way analysis of variance (ANOVA) for repeated measures showed statistically higher values at T2 and T3 for EL1 (p < 0.01), EL2 (p < 0.01) and EL3 (p < 0.01) following the 100 km journey. RT (p < 0.01) showed higher values at T2 and T3 after the 100 km journey and higher values at T2 (p < 0.01) following the 300 km journey. ET values were positively correlated with RT at T1, T2 and T3 following the 100 km journey and at T2 following the 300 km journey and positively correlated with serum cortisol concentration at T1, T2 and T3 following the 100 km journey and at T2 and T3 following the 300 km journey. Eye temperature monitoring with IRT allows quick and practical strategies to monitor an animal's physiological state and welfare during daily activities.

Chronophysiology of domestic animals

This review highlights recent findings on biological rhythms and discusses their implications for the management and production of domestic animals. Biological rhythms provide temporal coordination between organs and tissues in order to anticipate environmental changes, orchestrating biochemical, physiological and behavioural processes as the right process may occur at the right time. This allows animals to adapt their internal physiological functions, such as sleep-wake cycles, body temperature, hormone secretion, food intake and regulation of physical performance to environmental stimuli that constantly change. The study and evaluation of biological rhythms of various physiological parameters allows the assessment of the welfare status of animals. Alteration of biological rhythms represents an imbalance of the state of homeostasis that can be found in different management conditions.

Utilization of Infrared Thermography in Assessing Thermal Responses of Farm Animals under Heat Stress

Heat stress is a condition that can affect the health, performance, and welfare of farm animals. The perception of thermal stress leads to the activation of the autonomic nervous system to start a series of physiological and behavioral mechanisms to restore thermostability. One of these mechanisms is vasodilation of peripheral blood vessels to increase heat loss through the skin. Due to this aspect, infrared thermography has been suggested as a method to assess the thermal state of animals and predict rectal temperature values noninvasively. However, it is important to consider that predicting rectal temperature is challenging, and its association with IRT is not always a direct linear relationship. The present review aims to analyze the neurobiological response associated with heat stress and how thermal imaging in different thermal windows can be used to recognize heat stress in farmed ungulates.

Correlation and agreement between infrared thermography and a thermometer for equine body temperature measurements

Background and Aim

Body temperature is a vital sign that determines physical status. Infrared thermography (IRT) is more frequently used for assessing horses' temperature because of its ease of use and less contact with the horses, making it a safer measurement method. However, the accuracy of IRT remains unclear; therefore, this study aimed to assess the potential use of IRT as an alternative method for measuring horse body temperature.

Materials and Methods

Temperatures were measured in 14 horses. A digital thermometer was used to collect rectal temperature (RT), whereas a thermographic camera was used for IRT at three different positions to obtain the center of body temperature (CBT), head temperature (HT), and eye temperature (ET). The protocol was performed over 30 days, repeated thrice daily: morning (6:00-8:00), afternoon (14:00-15:00), and evening (17:00-19:00). Environmental factors, including humidity, ambient temperature, wind flow, and light intensity, were recorded indirectly according to the time of day and cooling device use.

Results

Mean RT, CBT, HT, and ET were 37.33°C, 34.08°C, 35.02°C, and 35.14°C, respectively. Center of body temperature was lower than RT by an average of 3.24°C (95% confidence interval [CI], 5.4°C-1.09°C). HT was lower than RT by an average of 2.3°C (95% CI, 4.33-0.28). The eye position showed the least difference between RT and infrared temperature, with an average of 2°C (95% CI, 0.7-3.92). However, there was no significant correlation between RT and infrared temperature at any position. Spray and vaporizer use significantly affected IRT and time of day (p = 0.05).

Conclusion

Although IRT has advantages in terms of non-invasiveness and reduced stress on horses, its accuracy and reliability may be compromised by environmental variables, which interfere with infrared measurement. Future research should specifically focus on investigating environmental factors.

Cardiac Biomarker Responses to Acute Exercise in Show Jumping Horses

Cardiac biomarkers are useful to identify cardiac muscle variations in human and equine medicine. The aim of this study was to investigate the acute effect of a bout of show jumping training on serum activity of cardiac and muscular biomarkers in healthy athletic horses to include cardiac troponin (cTnI), myoglobin (MB), aspartate amino transferase (AST), alanine amino transferase (ALT), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH). Serum samples were collected from seven Italian Saddle horses (three geldings and four mares; 10 ± 3 years; mean body weight 480 ±70 kg), regularly trained for show jumping at rest, immediately after exercise (show jumping simulate trial) and during the recovery period (30 and 60 min after exercise). ANOVA was applied to all parameters, and Pearson correlation coefficient t (r) evaluated. Immediately after exercise there was an increase in cTnI (P < .01), MB (P < .01), and CPK (P < .005); a positive correlation between cTnI and AST and between AST and LDH; and a negative correlation between cTnI and ALT and between ALT and CPK. Thirty minutes after exercise, there was a positive correlation between AST and ALT and between AST and LDH, while 60 mintues after exercise, there was a positive correlation between MB and LDH and a negative correlation between AST and CPK. The results obtained demonstrate the cardiac and muscular response to short-term intense exercise show jumping exercise.

Ocular and Superficial Body Thermographic Findings in Sled Dogs before and after Competition

Competitions involving sled dogs are rapidly growing and body temperature assessment could represent a prompt and non-invasive method of screening for potential pathological conditions during or after activity. The aim of this clinical study was to evaluate if thermography is able to monitor the pre- and post-competition ocular and superficial body temperature variations during a sled dog competition. It subsequently compared the data relating to the ocular temperatures in different race types: mid-distance (30 km) and sprint (≤16 km). Results showed a statistically significant increase in post-competition ocular temperature of both eyes, regardless of the length of the race. The relative increase in the temperatures of the other body surfaces was lower than the expected values, probably due to the influence of environmental and subjective factors such as the type of coat of the Siberian Husky or subcutaneous fat. Infrared thermography has therefore proved to be useful method in sled dog competition conditions for screening superficial temperature variations, as the investigation is normally conducted in an external environment and often in demanding work conditions.

Thermoregulation mechanisms and perspectives for validating thermal windows in pigs with hypothermia and hyperthermia: An overview

Specific anatomical characteristics make the porcine species especially sensitive to extreme temperature changes, predisposing them to pathologies and even death due to thermal stress. Interest in improving animal welfare and porcine productivity has led to the development of various lines of research that seek to understand the effect of certain environmental conditions on productivity and the impact of implementing strategies designed to mitigate adverse effects. The non-invasive infrared thermography technique is one of the tools most widely used to carry out these studies, based on detecting changes in microcirculation. However, evaluations using this tool require reliable thermal windows; this can be challenging because several factors can affect the sensitivity and specificity of the regions selected. This review discusses the thermal windows used with domestic pigs and the association of thermal changes in these regions with the thermoregulatory capacity of piglets and hogs.