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. 2025 Mar 10:12:1548906.
doi: 10.3389/fvets.2025.1548906. eCollection 2025.

Unique temperature change patterns in calves eyes and muzzles: a non-invasive approach using infrared thermography and object detection

Sueun Kim  1 , Norio Yamagishi  1 , Shingo Ishikawa  1 , Shinobu Tsuchiaka  1
Affiliations

Unique temperature change patterns in calves eyes and muzzles: a non-invasive approach using infrared thermography and object detection

Sueun Kim et al. Front Vet Sci. .

Abstract

This study investigates the potential of non-invasive, continuous temperature measurement techniques for assessing cattle welfare. We employed advanced object detection algorithms and infrared thermography to accurately extract and continuously measure temperatures of the eyes and muzzles of 11 calves over several months (total, 33 samples). A mobile thermal imaging camera was paired with the Mask R-CNN algorithm (object detection) trained on annotated datasets to detect eye and muzzle regions accurately. Temperature data were processed by outlier rejection, standardization, and low-pass filtering to derive temperature change patterns. Cosine similarity metrics and permutation tests were employed to evaluate the uniqueness of these patterns among the individuals. The average cosine similarity between eye and muzzle temperature changes in the same individual across 33 samples was 0.72, with permutation tests yielding p-values <0.01 for most samples, indicating pattern uniqueness. This study highlights the potential of high-frequency, non-invasive temperature measurements for detecting subtle physiological changes in animals without causing distress.

Keywords: AI object detection; cattle welfare monitoring; infrared thermography; non-invasive temperature measurement; temperature change patterns.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Results of using object detection to identify calves eye and muzzle. (A) Image of a calf captured using a standard camera. (B) Image of the eye region extracted by object detection. (C) Image of the muzzle region. The green-bound boxes represent object detection, while the green hatched areas denote pixel-wise object detection, also known as segmentation.
Figure 2
Figure 2
Analyzing and processing temperature data over time. (A) Temperature graph over time obtained by combining infrared temperature data and object extraction (B) after outlier rejection, (C) after standardization, (D) after low-pass filtering. The green line represents the filtered graph. (E) A pattern of temperature change over time.
Figure 3
Figure 3
Comparison of temperature change patterns in the eye and muzzle in the same individual (A–I). Green indicates eye and red, muzzles.
See this image and copyright information in PMC

References

    1. Giannetto C, Di Pietro S, Falcone A, Pennisi M, Giudice E, Piccione G, et al. . Thermographic ocular temperature correlated with rectal temperature in cats. J Therm Biol. (2021) 102:103104. doi: 10.1016/j.jtherbio.2021.103104, PMID: - DOI - PubMed
    1. de Freitas ACB, Vega WHO, Quirino CR, Junior AB, David CMG, Geraldo AT, et al. . Surface temperature of ewes during estrous cycle measured by infrared thermography. Theriogenology. (2018) 119:245–51. doi: 10.1016/j.theriogenology.2018.07.015, PMID: - DOI - PubMed
    1. de Ruediger FR, Yamada PH, Barbosa LGB, Chacur MGM, Ferreira JCP, de Carvalho NAT, et al. . Effect of estrous cycle phase on vulvar, orbital area and muzzle surface temperatures as determined using digital infrared thermography in buffalo. Anim Reprod Sci. (2018) 197:154–61. doi: 10.1016/j.anireprosci.2018.08.023, PMID: - DOI - PubMed
    1. George WD, Godfrey RW, Ketring RC, Vinson MC, Willard ST. Relationship among eye and muzzle temperatures measured using digital infrared thermal imaging and vaginal and rectal temperatures in hair sheep and cattle. J Anim Sci. (2014) 92:4949–55. doi: 10.2527/jas.2014-8087, PMID: - DOI - PubMed
    1. Soroko M, Howell K, Zwyrzykowska A, Dudek K, Zielińska P, Kupczyński R. Maximum eye temperature in the assessment of training in racehorses: correlations with salivary cortisol concentration, rectal temperature, and heart rate. J Equine Vet Sci. (2016) 45:39–45. doi: 10.1016/j.jevs.2016.06.005 - DOI

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