Assessing Pregnancy's Influence on Rectal and Corneal Temperature in Female Cats

Abstract

ABSTRACT

Objective

This study aimed to investigate the effect of pregnancy status on corneal temperature (CT) and rectal temperature (RT) in female cats.

Animals studied

Fifteen pregnant and fifteen anoestrus cats were included in this study.

Procedures

Pregnant cats had gestation periods ranging from 20 to 45 days, and vaginal smears were taken to assess the oestrous cycles of anoestrus cats. CT was measured using a FLIR E90 thermal camera, while RT was measured with a digital thermometer. Statistical analysis was conducted to evaluate temperature differences between the two groups.

Results

Anoestrus cats (38.4 ± 0.55°C) had a significantly higher RT compared to pregnant cats (37.89 ± 0.58°C) (p = 0.02). The right (R) CT of anoestrus cats (36.58 ± 1.19°C) and pregnant cats (36.55 ± 1.41°C) did not differ statistically (p > 0.05). Similarly, no significant difference was observed in the left (L) CT between anoestrus cats (36.94 ± 0.96°C) and pregnant cats (36.18 ± 1.61°C) (p > 0.05). Furthermore, there was no statistical difference between the R‐CT and L‐CT of the groups (p > 0.05). A positive and linear correlation was found between RT and R‐CT in pregnant cats (r = 0.38, R² = 0.14), with the regression equation y = ‐0.14x + 43.63.

Conclusion

This study demonstrates that pregnancy status significantly affects RT but not CT in female cats. Specifically, pregnant cats exhibited statistically lower RT compared to those in anoestrus. However, despite this statistical significance, RT may not be a reliable clinical indicator of pregnancy in cats. RCT is preferable as it provides a stress‐free, consistent, and reliable alternative to RT measurement in pregnant cats. Further research is needed to explore more consistent markers for pregnancy status in felines.

Introduction

Rectal temperature (RT) is a key indicator of core body temperature in clinical settings and plays an important role in diagnosing and managing pet diseases (Greer et al. 2007; Southward et al. 2006). However, not all cats and dogs tolerate this stressful technique well (Lamb and McBrearty 2013). Additionally, factors such as intestinal air, faeces and clumps can affect RT measurements, often resulting in slightly lower values that lag behind actual temperature changes. Alternative methods for measuring RT, such as infrared ear and eye thermometers, axillary temperature recordings and infrared thermography, have been explored (Idris et al. 2024; Lamb and McBrearty 2013; Yanmaz et al. 2015).

Animals may experience stress during RT measurement, increasing the risk of gastrointestinal bacterial cross-contamination (KuKanich et al. 2012). Stress is recognised as a critical factor affecting the healing process in veterinary patients. Therefore, clinical methods that minimise stress and defensive responses, especially in felines, are highly recommended (Rodan et al. 2022). Stress-induced defensive behaviour can lead to elevated body temperature, heart rate, respiration rate and stress hyperglycemia, potentially resulting in inaccurate diagnostic outcomes. When performing RT measurement, it is advisable to conduct this procedure towards the end of the physical examination, positioning the cat comfortably for easy access to the anus without excessive tail stretching. However, whenever possible, less stressful temperature measurement techniques should be prioritised (Bradley et al. 1999).

Infrared thermal cameras provide a non-invasive alternative for medical applications, aiding in diagnosis, prognosis and treatment planning. In veterinary medicine, these cameras have been shown to effectively monitor ocular temperature, revealing no significant differences between eye temperatures and demonstrating a direct correlation with RT (Giannetto et al. 2021; Riaz et al. 2023). Studies on multiple species have explored alternative methods for measuring body temperature, with variations in results depending on the body region examined and the type of thermometer used (Piccione et al. 2011).

Thermal imaging allows for temperature monitoring without physical contact, offering precise, real-time recordings of surface temperature distribution (Tan et al. 2009). This method reduces stress factors that could negatively affect animal well-being and cause behavioural changes, especially in cats. As creatures of habit and territorial nature, many cats find visits to the veterinarian stressful due to new environments, unfamiliar individuals, strong odours and confinement, which often provoke fear or anxiety. Implementing thermography in cats could help minimise their stress response, a significant benefit given their known susceptibility to stress (Amat et al. 2016).

Body temperature variations during the oestrous cycle can significantly affect clinical examination outcomes in felines (Ozcan et al., 2024) and ruminants (Riaz et al. 2023). Infrared thermography presents a non-invasive, real-time method for assessing ovarian activity in cats (Andrews et al. 2022) and early pregnancy diagnosis in cattle (Riaz et al. 2024).

The authors hypothesised that pregnancy status influences rectal body temperature. This study aimed to investigate the effect of pregnancy status on corneal temperature (CT) and RT in female cats.

Materials and Methods

Ethical Approvals

The measurements and assessments conducted on the female cats adhered to the guidelines set by the Association for Research in Vision and Ophthalmology regarding the ethical use of animals in ophthalmic and vision research. The cat owners provided informed consent for their animals to participate in the study. Ethical approval for this study was obtained from the XX University Animal Experiments Local Ethics Committee (approval date: 26.04.2024, approval number: 2024/10).

Animals

The study involved cats presented to the Faculty of Veterinary Medicine at XX University, specifically from the Department of Obstetrics and Gynaecology, for evaluation. A total of 30 crossbred cats were included in the study, comprising 15 pregnant cats and 15 anoestrus cats. The assessments were conducted in the examining room, with the cats accompanied by their owners.

Exclusion Criteria

The cats included in the study had complete medical histories, underwent thorough physical examinations and exhibited suitable temperaments. These cats were then moved to a designated area for measuring their body temperature, with all readings presented in degrees Celsius (°C). The objective in this area was to obtain accurate digital and thermal measurements while minimising stress factors that could potentially impact the results. Female cats with chronic diseases, intestinal disorders, acute infections, or significant stress due to their environment were excluded from the study.

The physicians conducting the pregnancy assessment, corneal evaluation and temperature measurements are three separate professionals. The professionals were unaware of the measurement results to avoid bias.

Environmental Conditions in the Examination Room

The cats were confined to a specific area of the room for 20 min to facilitate their acclimatisation before measurements commenced, as stated in previous literature (Ozcan et al. 2024). This area was attended by two qualified veterinarians specialising in feline medical care. All potential sources of airflow were effectively eliminated. Temperature measurements in the room indicated a consistent temperature of 25.5°C (ranging from a minimum of 25 to a maximum of 26°C) and a relative humidity of 58.0% (minimum 51% and maximum 65%). The room was shielded from direct sunlight. The equipment used to monitor the room temperature and relative humidity was positioned at a height of 3 metres above the ground, ensuring an isolated environment. CT was assessed using a thermal camera, while RT was measured with a digital thermometer. Simultaneous measurements were recorded during this assessment, which took place between 09:00 a.m. and 11:00 a.m.

Corneal Temperature Measurement

After acclimating the animals to the environment, temperature measurement using an infrared thermal camera was prioritised as the first measurement. This decision was made to minimise stress that RT measurement could induce in the animals, which might affect the infrared thermal camera results. CT measurements were conducted as previously described in the literature (Polat and Yanmaz 2024). Measurements were symmetrically taken from both the right and left cornea by the same physician using an infrared thermal camera (FLIR E90, 160 × 120 pixels, Systems, Inc., Sweden), positioned approximately 90 cm away from the cats. Only two physicians were present in the examination room during the measurements. The thermograms obtained from the thermal camera were analysed using FLIR Tools software, the original application for the device. The region of interest (ROI) is illustrated in Figure 1, featuring various colour palettes.

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Rectal Temperature Measurement

The research by Giannetto et al. (2021) served as a reference point for the assessment of RT. A previously calibrated digital thermometer (Albert KERBL, GmbH, Germany) was utilised for each measurement. Glycerin was administered to the probe of the digital thermometer prior to rectal insertion. The probe was inserted approximately 3 cm into the rectum. The device measures temperatures between 32.0 and 42.0°C, with an accuracy of ±0.1°C. This rectal thermometer exhibits a speedy response time of around 9 to 11 seconds and emits an audio alert upon reaching the maximum temperature. After detecting the signal from the thermometer, it was extracted from the rectum and the data were then recorded on the display.

Ophthalmic Examination

Fluorescein sodium staining (Fluorescite Ophthalmic Disclosing Agent, 10% Fluorescein Sodium) was utilised to evaluate the presence of erosions on the ocular surface of the cats. Additionally, a comprehensive clinical examination was conducted by a veterinary surgeon to assess various disorders that could affect corneal CT, including epiphora, lacrimation, eye discharge, blepharospasm, entropion and corneal erosion.

Ultrasonographic Evaluation of the Genital Organs and Vaginal Smears

The ultrasonography assessment was conducted following the procedures outlined by Zambelli and Prati (2006). A transabdominal ultrasonography examination was performed using a 5 MHz convex probe in B-mode (Versana Active, USA) to determine the pregnancy status of the cats. The gestation period for the pregnant cats ranged from 20 to 45 days. During the ventro-dorsal examination, both the ovaries and uterus were evaluated (Safak and Yilmaz 2023). Cats displaying maternal-foetal structures were classified as part of the pregnant group. Additionally, a vaginal swab was performed to assess the reproductive cycles of the non-pregnant cats.

The methodology for vaginal smears and the assessment of sexual cycles followed the procedures outlined by Termelioğlu et al. (2022). The vaginal smear procedure involved collecting cells from the vaginal tissue using a cotton swab, which were then evenly spread on a pre-labelled clean slide. The collected cells were air-dried and subsequently fixed with ethyl alcohol on the slide, as previously described in the study (Denda et al. 2012). The slides were then fully coated with Giemsa stain using a dropper to ensure uniform distribution. After the Giemsa-stained vaginal smear preparations dried in the air, they were analysed under a light microscope (Leica DM500, Germany). The cells were classified based on their morphology into parabasal, intermediate, superficial, or keratinised superficial types. Cats identified as being in the anoestrus period, as determined by cell profiles, were selected as the non-pregnant group.

Statistical Analysis

The statistical analyses were conducted using IBM SPSS version 22.0. Data normality was assessed using the Shapiro-Wilk test. Due to the normal distribution of weight, RT, right corneal temperature (RCT) and left corneal temperature (LCT), the independent samples t-test was employed. Body temperatures were acquired through various techniques, including the rectal measurement as the reference method to determine RCT, which facilitated the Bland-Altman analysis (Bland and Altman 1986). Passing-Bablok regression analysis (Passing and Bablok 1983) was used to evaluate the linearity and adequacy of two distinct measurement methods. This choice was made because Passing-Bablok analysis accounts for measurement errors in both independent and dependent variables, thereby providing more robust and reliable results. This method is widely used in clinical and biological research, offering accurate data to assess the concordance between measuring techniques. The derived regression equations were employed to investigate the correlation between RT and CT. Statistical significance was set at p < 0.05 and results are presented as mean ± standard deviation.

Results

The study included a total of 30 crossbred cats, with 15 categorised as pregnant and 15 as non-pregnant (anoestrus). The mean age of the pregnant cats was 2.3 ± 1.68 years, while the mean age of the anoestrus cats was 1.53 ± 0.7 years. The average body weight of the pregnant cats was 3.33 ± 0.61 kg, compared to 2.96 ± 0.5 kg for the anoestrus cats. No significant differences were observed between the groups concerning RCT, LCT, age and body weight (p > 0.05) (Table 1).

TABLE 1 Grouped data on RT, RCT, LCT, weight and age.

Pregnancy status	n	RT	RCT	LCT	Weight	Age
Pregnant	15	37.89 ± 0.58	37.46 ± 1.12	37.34 ± 1.07	3.33 ± 0.61	2.3 ± 1.68
Anoestrus	15	38.4 ± 0.55	37.88 ± 0.59	37.68 ± 0.66	2.96 ± 0.5	1.53 ± 0.78
p		0.021	—	—	—	—

RT was significantly lower in pregnant cats (37.89 ± 0.58°C) than in anoestrous cats (38.4 ± 0.55°C, p = 0.021). The RCT was 37.46 ± 1.12°C in pregnant cats and 37.88 ± 0.59°C in anoestrus cats, with no significant difference (p > 0.05). Similarly, the LCT was 37.34 ± 1.07°C in pregnant cats and 37.68 ± 0.66°C in anoestrus cats, also showing no significant difference (p > 0.05) (Figure 2).

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The Bland Altman plot analysis results for RT and CT are as shown in Figure 3. In these graphs, RT and right-left CT values of pregnant and anoestrus cats were analysed. Bias was positive for all regions. Upper limit of agreement (ULA) and lower limit of agreement (LLA) values varied. In pregnant cats, the bias between RT-RCT was +0.46, ULA was +2.74 and LLA was -1.87 (correlation coefficient (r): 0.38 and determination coefficient (R²): 0.14). The bias between RT-LCT was +0.55, ULA was +2.69 and LLA was -1.59 (r: 0.35 and R²: 0.12). In anoestrus cats, the bias between RT-RCT was +0.51, ULA was +2.13 and LLA was -1.11 (r: -0.1 and R²: 0.01). The bias between RT-LCT was +0.71, ULA was +2.34 and LLA was -0.91 (r: 0.01 and R²: 0.003). Among the several sites where measurements are taken in pregnant cats, the RCT method showed the least amount of variation and the greatest proportion of values that were within the acceptable range for clinical agreement. This makes it a viable alternative to the RT method. Although RT is the gold standard, it was compared with temperature readings from other parts of the body to find the average difference and 95% confidence intervals for each comparison (Table 2). There was a moderate correlation (r = 0.38) between RT-RCT and a moderate correlation (r = 0.35) between RT-LCT in pregnant cats. Nevertheless, there was a weak correlation observed between RT and other temperature zones in anoestrus cats.

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TABLE 2 Bias, limit of agreements, correlation coefficient and determination coefficient for pregnant and anoestrus cats.

Pregnancy status	n	Method	Bias	ULA	LLA	r	R2
Pregnant	15	RT-RCT	+0.46	+2.74	−1.87	0.38	0.14
15	RT-LCT	+0.55	+2.69	−1.59	0.35	0.12
Anoestrus	15	RT-RCT	+0.51	+2.13	−1.11	−0.1	0.01
	15	RT-LCT	+0.71	+2.34	−0.91	0.01	0.003

The regression equation between RT-RCT in pregnant cats was y = -0.03x + 38.74 and RT-LCT was y = 0.27x + 27.41. In anoestrus cats, the regression equation between RT-RCT was y = -0.14x + 43.63 and RT-LCT was y = -0.33x + 50.27 (Figure 4) (Table 3). According to this equation representing the relationship between RT and RCT in pregnant cats, the slope (-0.03) was negative, indicating that RCT decreased slightly as RT increased. However, this slope is very small, suggesting that in practice there may not be a significant difference between these two measurements. The slope (0.27) in the equation representing the relationship between RT and LCT was positive, indicating that LCT increased as RT increased. This indicated that RT offered a stronger correlation for predicting LCT in pregnant cats.

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TABLE 3 Passing-Bablok regression analysis results for pregnant and anoestrus cats.

Pregnancy status	n	Method	Regression Equation	Slope	Y-intercept
Pregnant	15	RT-RCT	y = −0.03x + 38.74	−0.03	38.74
	15	RT-LCT	y = 0.27x + 27.41	0.27	27.41
Anoestrus	15	RT-RCT	y = −0.14x + 43.63	−0.14	65.89
	15	RT-LCT	y = −0.33x + 50.27	−0.33	50.27

In anoestrus cats, the slope between RT-RCT and RT-LCT was greater (-0.14 and -0.33, respectively). Since this negative slope indicates a significant negative correlation between RT and CT measurements, it was thought that there may be significant differences between the two measurement methods.

Discussion

RT is a vital indicator of core body temperature, essential for diagnosing and treating pet diseases. However, traditional methods of measuring RT often induce stress in animals, which can have adverse effects, particularly in pregnant cats. Stress during pregnancy may lead to complications such as premature birth and restricted foetal growth (Lykkesfeldt 2007; Schneider and Oliveira 2004).

In this study, an alternative, stress-free method was proposed for estimating the core temperature of pregnant cats using CT measurements obtained with a thermal camera. The findings indicate that using a thermal camera to assess CT in pregnant cats provides a non-invasive, stress-free alternative to RT, with a moderate correlation to core body temperature. This innovative technique could enhance the welfare of pregnant cats while ensuring accurate monitoring of their health status.

Our research findings indicate that the RT of pregnant cats is lower compared to that of non-pregnant cats, with this temperature difference achieving statistical significance. This suggests that pregnancy significantly affects the body temperature of cats, as evidenced by the observed decrease in RT among pregnant individuals. This aligns with previous studies in both humans (Hartgill et al. 2011) and animals (Bu and Lephart 2005; Gamo et al. 2013), which also reported a decline in body temperature during pregnancy.

For example, in the initial stages of pregnancy in killer whales, body temperature and progesterone levels rise concurrently. However, a gradual decline in temperature occurs before parturition, with the most significant drop observed the day prior to giving birth, averaging 0.8°C (Katsumata et al. 2006). While predicting the timing of parturition was not the primary aim of this study, we recognise that hormonal fluctuations, including those related to progesterone, may influence RT. This underscores the complexity of temperature regulation during pregnancy and highlights the need for further research to explore these relationships in greater detail.

The observed decline in body temperature during pregnancy may also be attributed to hormonal fluctuations that occur throughout this period. Key hormones such as estradiol-17β, luteinising hormone, and progesterone are secreted at varying rates in female cats during pregnancy (Kustritz 2006). Numerous studies have investigated the relationship between body temperature and various reproductive indicators, including oestrus, pregnancy and parturition, in several domesticated animals, such as cattle, sheep, horses and dogs (Ewbank 1969; Verstegen-Onclin and Verstegen 2008; Auclair-Ronzaud et al. 2020).

In cattle, fluctuations in hormone levels—specifically progesterone—during pregnancy are associated with changes in body temperature due to the thermogenic effect of progesterone (Kornmatitsuk et al. 2002; Nabenishi and Yamazaki 2017; Suthar et al. 2012). The primary sources of progesterone, which significantly influences the oestrous cycle and the maintenance of pregnancy, are the corpus luteum and/or the placenta (Wiltbank et al. 2014). As pregnancy progresses, the corpus luteum remains intact and produces elevated levels of progesterone, leading to an increase in vaginal temperature (Suthar et al. 2012; Wiltbank et al. 2014). These findings illustrate that distinct clinical observations can manifest across different animal species and highlight that various anatomical sites exhibit unique patterns of body temperature regulation. This suggests that temperature assessments could potentially provide valuable insights into reproductive status and overall health in pregnant animals.

Since the cornea is located on the outer surface of the eye, its function can be influenced by variations in external temperatures and exposure to environmental factors (Yamada et al. 2024). This underscores the importance of conducting CT measurements prior to any other eye examinations in this study. The absence of significant disparities in CT across different conditions may be linked to the influence of external factors, such as fluctuations in ambient temperature, humidity and radiation. Environmental factors, such as ambient temperature and humidity, can play a crucial role in influencing the accuracy of temperature measurements, including those taken with thermal cameras. Variations in ambient temperature can lead to fluctuations in the surface temperature of the cornea, which may, in turn, affect the measurement of CT. Additionally, changes in humidity could impact the thermal conductivity and heat dissipation from the skin, potentially altering temperature readings.

Additionally, internal factors can also affect individual thermal characteristics. These include variations in body temperature, gender, the menstrual cycle, blood flow in the eyes, changes in pupil size and differences in the depth of the anterior chamber (Kawali et al. 2024). The lack of significant differences in CT among the groups in our study may be explained by these external and internal influences, as highlighted in previous research (Kawali et al. 2024). The authors note the importance of considering temperature discrepancies in specific thermographs when assessing CT.

In our investigation, no significant difference was observed in CT between the right and left sides. However, our statistical analysis indicated a potential link between RT and CT in pregnant cats. The Bland-Altman plot analysis (Bland and Altman 1986) revealed moderate agreement between RT and RCT in pregnant cats, with a smaller difference between the two measurement methods compared to other groups. Furthermore, the results suggest a linear relationship between RT and RCT, indicating that RT could be a reliable predictor for RCT in this population.

The reason for prioritising the RCT in our study stems from literature findings suggesting that the right eye may be more sensitive to temperature changes. Elias et al. (2021), in a study evaluating eye temperatures before and after exercise in 465 greyhound dogs, reported that the temperature of the right eye was more responsive to environmental and physiological changes. Therefore, they emphasised its potential value in assessing average eye temperature. This finding suggests that RCT may yield more prominent results when evaluating the relationship between corneal and systemic temperatures, such as rectal temperature. Additionally, the correlation coefficient between RCT and RT in our study was higher than that of LCT and RT, further supporting the choice of prioritising RCT in the analysis. Consequently, both the literature and our statistical results justified the decision to emphasise RCT in the discussion.

The study employed Passing-Bablok regression analysis to evaluate the linear correlation between the two measurement techniques. The results indicated that in pregnant cats, considering the RCT measurement method is advisable. This method showed a weak negative correlation with RT, suggesting that RCT has significantly greater consistency with RT compared to other methods.

In contrast, both measurement techniques exhibited a low level of concordance with RT in anoestrus cats. This finding highlights the potential limitations of using RCT and other temperature measurement methods as reliable alternatives to RT in this group. Overall, the analysis supports the recommendation of RCT as a viable option for monitoring body temperature in pregnant cats, while emphasising the need for caution when interpreting results from anoestrus cats.

Research has shown that ocular temperature increases following physical activity, with the right eye being particularly susceptible to temperature variations. This observation highlights the importance of considering both environmental and biological factors when assessing ocular temperature (Casas-Alvarado et al. 2022). It is also reported that RCT in humans increases depending on the clinical severity of psychological disorders (Maller et al. 2016). Although our findings support existing research, studies are insufficient to explain why there is such a temperature change only in the right cornea. In our comparisons of RT and RCT, we found that RCT exhibited a lower bias and values that were more closely aligned with RT. Additionally, the correlation coefficient for the right cornea was higher, indicating more reliable and consistent outcomes. The RT-RCT measurements provided dependable results, revealing a significant amount of data. The minimal slope between RT and RCT indicates that the difference between these two measurements is negligible, further confirming the consistency of the data. Given these considerations, RCT is favoured for measuring body temperature in pregnant cats, as it closely correlates with RT and offers more reliable results.

The method proposed in this study offers several advantages for determining body temperatures in pregnant cats. First, measuring CT provides a non-invasive, non-contact approach, significantly reducing stress compared to traditional RT measurements. This technique ensures a more comfortable experience for both the cats and their owners, as well as for the veterinarian. It proves especially promising for monitoring the health status of pregnant cats, where close observation is crucial. Additionally, this study contributes new evidence to the growing body of research utilising thermal cameras for estimating body temperature in cats. Furthermore, our findings indicate that body temperatures may be lower in pregnant cats compared to those in anoestrus. Consequently, pregnant cats require more sensitive evaluation than their anoestrus counterparts.

This study has several limitations that warrant consideration. First, while the investigation aimed to assess CT measurements as a non-invasive alternative to RT measurements in pregnant cats, it is essential to clarify that RT, although not invasive in the traditional sense, may still induce stress or discomfort in animals. Secondly, the study was conducted on a relatively small sample size of 15 pregnant cats and 15 anoestrus cats and the gestational ages of the pregnant cats varied from 20 to 40 days. The influence of progesterone on body temperature is significant; however, the varying stages of gestation may affect CT levels. Although the study was conducted in a clinical setting, environmental factors were controlled to minimise external influences. Future research evaluating CT measurements under varying environmental conditions could further enhance the generalisability and clinical applicability of the findings. The practicality of RT measurements, where immediate results can be obtained without the need for environmental adjustments, is an advantage that should not be overlooked. Moreover, the cost implications of utilising thermal camera technology compared to RT measurements must be discussed, as the former requires specialised equipment that may not be accessible in all veterinary practices. Finally, further research is needed to explore the underlying reasons for the observed differences between LCT and RCT, as these factors were not fully addressed in this study.

Conclusions

This study demonstrates that using a thermal camera to measure CT in pregnant cats is a reliable and non-intrusive alternative to traditional RT measurements. The results revealed a strong correlation between right RCT and RT, particularly in pregnant cats. RCT exhibited a smaller bias and a higher correlation coefficient, indicating that it is a more consistent and dependable method. Previous studies have shown that RCT reflects changes related to physical activity or stress, with reliable results observed in cats, further emphasising its consistency as a clinical indicator.

This non-invasive approach can help reduce the stress associated with conventional RT measurements, which is crucial for preventing complications such as preterm labour and restricted foetal growth in pregnant cats. Thermal imaging is particularly beneficial in veterinary care as it reduces the need for handling, provides quicker results and minimises stress, which is critical for the health of the animal. Additionally, our findings showed that pregnant cats have lower RT compared to non-pregnant cats, which is consistent with previous studies on temperature variations during pregnancy across various animal species. This observation emphasises the value of thermal imaging for assessing pregnancy-specific changes in body temperature.

In conclusion, the adoption of thermal camera technology can significantly improve healthcare and animal welfare by providing a stress-free, accurate and convenient method for monitoring the health of pregnant cats. Future research should focus on applying thermal imaging to monitor pregnancy in other species, as this technology could be an invaluable tool in various veterinary fields. Additionally, further validation studies are needed to confirm the efficacy of thermal imaging in different clinical settings and a cost-benefit analysis should be conducted to evaluate its practicality and value in routine veterinary care.

Author Contributions

Candemir Ozcan: supervision, conceptualisation, data curation, formal analysis, investigation, methodology, writing–original draft. Tarik Safak: supervision, conceptualisation, data curation, formal analysis, investigation, methodology, writing–review and editing. Ayse Basak Dellalbasi: investigation, data curation. Elif Dogan: investigation. All authors checked the final version of the publication and reached a consensus.

Ethics Statement

This study conducted following approval by the Kastamonu University Local Ethics Committee of Animal Experimentation (date: 26.04.2024, approval number: 2024/10).

Data Availability Statement

The dataset is openly available in the Mendeley Data repository: https://doi.org/10.17632/b9xrxh29rc.1

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