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Review article
Austral J. Vet. Sci.
Vol 58, e5808 (2026)
DOI: 10.4206/ajvs.58.08

Understanding heat stress in pasture‑based dairy cows: Challenges and innovations from thermal indices to multivariate sensor technologies

1 DeLaval S.A. Osorno, Chile
2 Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, La Pintana, Santiago, Chile.
3 Facultad de Ciencias Agrarias, Universidad Nacional del Litoral, Esperanza, Santa Fe, Argentina.
4 Wageningen Livestock Research, Wageningen University and Research, Wageningen, the Netherlands.
Keywords: heat stress thermal indices dairy cattle pasture-based system physiological parameters

Submitted: 2026-02-25

Accepted: 2026-04-28

Published: 2026-06-25

*Corresponding author:
enrique.bombal@delaval.com

How to Cite

Bombal, E., Cartes, D., Toffoli, G., & Strappini, A. (2026). Understanding heat stress in pasture‑based dairy cows: Challenges and innovations from thermal indices to multivariate sensor technologies. Austral Journal of Veterinary Sciences, 58, e5808. https://doi.org/10.4206/ajvs.58.08

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Copyright (c) 2026 Enrique Bombal, Daniel Cartes, Guillermo Toffoli, Ana Strappini

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

Heat stress is an increasingly critical challenge for modern dairy production, particularly in pasture‑based systems where cows are directly exposed to solar radiation, humidity, wind, and high temperatures. This review synthesises the current evidence on environmental thermal indices, physiological responses, behavioural adaptations, and sensor-based technologies relevant to heat stress assessment in grazing dairy cattle. A narrative review of peer-reviewed and grey literature (2015–2026) was conducted across major scientific databases, focusing on studies that developed or validated thermal indices, compared them with animal-based indicators, or quantified their impacts on performance and health. The findings show that the Temperature Humidity Index (THI), although widely used, has limited accuracy in outdoor conditions owing to its exclusion of solar radiation and wind. Updated indices, including the adjusted THI, Heat Load Index (HLI), Comprehensive Climate Index (CCI), Dairy Heat Load Index (DHLI), and Grazing Heat Load Index (GHLI), demonstrate better alignment with physiological responses under grazing conditions. Early and sensitive indicators, such as respiratory rate (RR), panting, and rising body temperature (BT), provide direct insight into the loss of thermal balance, whereas reductions in rumination, shifts in feeding behaviour, and increased shade-seeking reflect behavioural adaptation. Emerging evidence also highlights heat-induced dysbiosis in the rumen and intestinal microbiome, with implications for metabolism, immunity, and reproductive function. Sensor-based technologies, including rumen boluses, infrared thermography, accelerometers, and subcutaneous or vaginal temperature devices, enhance real-time monitoring and support early detection, particularly in extensive outdoor environments. Overall, integrating multivariable climate indices with animal-centred physiological and behavioural monitoring provides a more accurate and responsive framework for heat stress detection, risk assessment, and management in pasture-based dairy systems, supporting productivity, welfare, and long-term system resilience.

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References

  1. Arias, R.A., Delgado, C., Keim, J.P., & Gandarillas, M. (2021). Use of the comprehensive climate index to estimate heat stress response of grazing dairy cows in a temperate climate region. Journal of Dairy Research, 88(2), 154-161. https://doi.org/10.1017/S0022029921000406
  2. Arias, R.A., Heinsohn, J., Keim, J.P., Pinto, R., & Bombal, E. (2025). Percep¬tion of Chilean dairy farmers facing the growing heat stress events in the country. Austral Journal of Veterinary Sciences, 57, e5704. https:// doi.org/10.4206/ajvs.57.04
  3. Arias, R.A., Herrera, C., Larraín, R., González, F., Mader, T.L., & Velásquez, A. (2018). Physiological and behavioural response of two dairy cows’ genotypes during summertime in the central region of Chile. Aus¬tral Journal of Veterinary Sciences, 50(1), 9-14. https://doi.org/10.4067/ S0719-81322018000100103
  4. Arias, R.A., Keim, J.P., Pinto, R., & Bombal, E. (2024). Estimation of the economic impact of heat stress on the Chilean dairy regions by using two comfort thermal indices. International Journal of Biometeorology, 68, 1823-1836. https://doi.org/10.1007/s00484-024-02709-2
  5. Arias, R.A., Mader, T.L., & Escobar, P.C. (2008). Climatic factors af¬fecting cattle performance in dairy and beef farms. Archivos de Medicina Veterinaria, 40(1), 7-22. http://dx.doi.org/10.4067/S0301-732X2008000100002
  6. Aubé, L., Meunier, B., & Lardy, R. (2026). Measuring shade use of dairy cattle at pasture with an on-cow light sensor: A case study. Comput¬ers and Electronics in Agriculture, 240, 111152. https://doi.org/10.1016/j. compag.2025.111152
  7. Bang, N.N., Gaughan, J.B., Hayes, B.J., Lyons, R.E., & McNeill, D.M. (2022). Application of infrared thermal technology to assess the level of heat stress and milk yield reduction of cows in tropical smallholder dairy farms. Journal of Dairy Science, 105(10), 8454-8469. https://doi. org/10.3168/jds.2021-21343
  8. Bar, D., Kaim, M., Flamenbaum, I., Hanochi, B., & Toaff-Rosenstein, R.L. (2019). Technical note: Accelerometer-based recording of heavy breathing in lactating and dry cows as an automated measure of heat load. Journal of Dairy Science, 102(4), 3480-3486. https://doi. org/10.3168/jds.2018-15186
  9. Becker, C.A., Collier, R.J., & Stone, A.E. (2020). Invited review: Physiolog¬ical and behavioral effects of heat stress in dairy cows. Journal of Dairy Science, 103(8), 6751-6770. https://doi.org/10.3168/jds.2019-17929
  10. Becker, C., Aghalari, A., Marufuzzaman, M., & Stone, A. (2021). Predicting dairy cattle heat stress using machine learning techniques. Journal of Dairy Science, 104(1), 501-524. https://doi.org/10.3168/jds.2020-18653
  11. Berman, A. (2005). Estimates of heat stress relief needs for Holstein dairy cows. Journal of Animal Science, 83(6), 1377-1384. https://doi. org/10.2527/2005.8361377x
  12. Bewley, J.M., Einstein, M.E., Grott, M.W., & Schutz, M.M. (2008). Com¬parison of reticular and rectal core body temperatures in lactating dairy cows. Journal of Dairy Science, 91(12), 4661-4672. https://doi. org/10.3168/jds.2007-0835
  13. Blackshaw, J.K., & Blackshaw, A.W. (1994). Heat stress in cattle and the effect of shade on production and behaviour: A review. Australian Journal of Ex¬perimental Agriculture, 34(2), 285-295. https://doi.org/10.1071/EA9940285
  14. Boehmer, B.M. (2015). Ruminal temperature as a measure of body tem¬perature of beef cows and relationship with ambient temperature. Professional Animal Scientist, 31(4), 387-393. https://doi.org/10.15232/ pas.2014-01336
  15. Bohmanova, J., Misztal, I., & Cole, J.B. (2007). Temperature-humidity indi¬ces as indicators of milk production losses due to heat stress. Journal of Dairy Science, 90(4), 1947-1956. https://doi.org/10.3168/jds.2006-513
  16. Brito, L.F., Heringstad, B., Klaas, I.C., Schodl, K., Cabrera, V.E., Stygar, A., Iwersen, M., Haskell, M.J., Stock, K.F., Gengler, N., Bewley, J., Hostens, M., Vasseur, E., & Egger-Danner, C. (2025). Invited review: Using data from sensors and other precision farming technologies to enhance the sustainability of dairy cattle breeding programs. Journal of Dairy Science, 108(10), 10447-10474. https://doi.org/10.3168/jds.2025-26554
  17. Bryant, J.R., Huddart, F.J., & Schütz, K.E. (2023). Development of a heat load index for grazing dairy cattle. New Zealand Journal of Agricultural Research, 66(6), 665-679. https://doi.org/10.1080/00288233.2022.2114504
  18. Bryant, J.R., López-Villalobos, N., Pryce, J.E., Holmes, C.W. & Johnson, D.L. (2007). Quantifying the effect of thermal environment on pro¬duction traits in three breeds of dairy cattle in New Zealand. New Zealand Journal of Agricultural Research, 50(3), 327-338. https://doi. org/10.1080/00288230709510301
  19. Buffington, D.E., Collazo-Arocho, A., Canton, G.H., Pitt, D., Thatcher, W.W., & Collier, R.J. (1981). Black globe-humidity index (BGHI) as com¬fort equation for dairy cows. Transactions of the American Society of Ag¬ricultural Engineers, 24(3), 711-714. https://doi.org/10.13031/2013.34325
  20. Cardoso, C.S., von Keyserlingk, M.A.G., Hötzel, M.J., Robbins, J., & Weary, D.M. (2018). Hot and bothered: Public attitudes towards heat stress and outdoor access for dairy cows. PLoS One, 13(10), e0205352. https://doi.org/10.1371/journal.pone.0205352
  21. Cardoso, C.S., von Keyserlingk, M.A.G., Machado Filho, L.C.P., & Hotzel, M.J. (2021). Dairy heifer motivation for access to a shaded area. Ani¬mals, 11(9), 2507. https://doi.org/10.3390/ani11092507
  22. Cartes, D., Held-Montaldo, R., & Sepúlveda-Varas, P. (2025). Behavior of transition dairy cows managed outdoors during the autumn and spring calving seasons. Animals, 15(5), 621. https://doi.org/10.3390/ ani15050621
  23. Cartes, D., Strappini, A., Matamala, F., Held-Montaldo, R., & Sepúlve¬da-Varas, P. (2021). Responses of outdoor housed dairy cows to shade access during the prepartum period under temperate summer condi¬tions. Animals, 11(10), 2911. https://doi.org/10.3390/ani11102911
  24. Chen, L., Shen, Y., Wang, C., Ding, L., Zhao, F., Wang, M., Fu, J., & Wang, H. (2019). Megasphaera elsdenii lactate degradation pattern shifts in rumen acidosis models. Frontiers in Microbiology, 10, 162. https://doi. org/10.3389/fmicb.2019.00162
  25. Chen, L., Thorup, V.M., Kudahl, A.B., & Østergaard, S. (2024). Effects of heat stress on feed intake, milk yield, milk composition, and feed ef¬ficiency in dairy cows: A meta-analysis. Journal of Dairy Science, 107(5), 3207-3218. https://doi.org/10.3168/jds.2023-24059
  26. Chen, S., Luo, S., & Yan, C. (2022). Gut microbiota implications for health and welfare in farm animals: A review. Animals, 12(1), 93. https://doi. org/10.3390/ani12010093
  27. Chen, S., Wang, J., Peng, D., Li, G., Chen, J., & Gu, X. (2018). Exposure to heat-stress environment affects the physiology, circulation levels of cytokines, and microbiome in dairy cows. Scientific Reports, 8, 14606. https://doi.org/10.1038/s41598-018-32886-1
  28. Chick, S., Ataei, Kachouei, M., Knowlton, K., & Ali, M.A. (2024). Func¬tionalized Graphene-Based Biosensors for Early Detection of Subclin¬ical Ketosis in Dairy Cows. ACS Applied Materials & Interfaces, 16(39), 51932-51943. https://doi.org/10.1021/acsami.4c07715
  29. Chung, H., Li, J., Kim, Y., Van Os, J.M.C, Brounts, S.H., & Choi, C.Y. (2020). Using implantable biosensors and wearable scanners to mon¬itor dairy cattle’s core body temperature in real time. Computers and Electronics in Agriculture, 174, 105453. https://doi.org/10.1016/j.com¬pag.2020.105453
  30. de Sousa, K.T., Deniz, M., Moro, F.M., Cordova, I., Martinez, M. & Dittrich, J.R. (2021). Developing of a model to predict lying behavior of dairy cows on silvopastoral system during the winter season. Internation¬al Journal of Biometeorology, 65, 1781-1786. https://doi.org/10.1007/ s00484-021-02121-0
  31. Deniz, M., de Sousa, K.T., Moro, M.F., do Vale, M.M., Dittrich, J.R., Macha¬do Filho, L.C.P., & Hötzel, M.J. (2021). Social hierarchy influences dairy cows’ use of shade in a silvopastoral system under intensive rotation¬al grazing. Applied Animal Behaviour Science, 244, 105467. https://doi. org/10.1016/j.applanim.2021.105467
  32. Deniz, M., Schmitt Filho, A.L., Hötzel, M.J., de Sousa, K.T., & Machado Filho, L.C.P. (2020). Microclimate and pasture area preferences by dairy cows under high biodiversity silvopastoral system. Internation¬al Journal of Biometeorology, 64, 1877-1887. https://doi.org/10.1007/ s00484-020-01975-0
  33. Deniz, M., Sena, A.R., De Sousa, K.T., Vieira, F.M.C., de Souza, E.R., Hötzel, M.J., & Dittrich, J.R. (2025). Herd dominance influences dairy cows' use of heat abatement resources in a silvopastoral system. Animals, 15(12), 1791. https://doi.org/10.3390/ani15121791
  34. Diniso, Y.S., Zhou, L., & Jaja, I.F. (2022). Dairy farmers’ knowledge and perception of climate change in the Eastern Cape province, South Af¬rica. International Journal of Climate Change Strategies and Management, 14(2), 168-179. https://doi.org/10.1108/IJCCSM-11-2020-0120
  35. Džermeikaitė, K., Krištolaitytė, J., Malašauskienė, D., Arlauskaitė, S., Gir¬dauskaitė, A., & Antanaitis, R. (2025). The impact of heat stress on dairy cattle: Effects on milk quality, rumination behaviour, and retic¬ulorumen pH response using machine learning models. Biosensors, 15(9), 608. https://doi.org/10.3390/bios15090608
  36. Feng, L., Zhang, Y., Liu, W., Du, D., Jiang, W., Wang, Z., Li, N., & Hu, Z. (2023). Altered rumen microbiome and correlations of the metabolome in heat-stressed dairy cows at different growth stages. Microbiology Spectrum, 11(6), e0331223. https://doi.org/10.1128/spectrum.03312-23
  37. Foroushani, S., & Amon, T. (2022). Thermodynamic assessment of heat stress in dairy cattle: Lessons from human biometeorology. Interna¬tional Journal of Biometeorology, 66, 1811-1827. https://doi.org/10.1007/ s00484-022-02321-2
  38. Furukawa, E., Ozawa, T., Higaki, S., Suda, T., Sasaki, Y., Murayama, K., No¬guchi, M., & Yoshioka, K. (2024). Changes in skin temperature and behaviors of preweaning Holstein calves in a hot environment moni¬tored by a multimodal tail-attached device. JDS Communications, 5(4), 332-337. https://doi.org/10.3168/jdsc.2023-0515.
  39. Gaughan, J.B., & Lees, J.C. (2010). Categorising heat load on dairy cows. 28th Bi¬ennial Conference of the Australian Society of Animal Production, Armi¬dale, NSW, Australia. Australian Society of Animal Production, Brisbane, Queensland, Australia. https://espace.library.uq.edu.au/view/UQ:238138
  40. Gaughan, J.B., Mader, T.L., Holt, S.M., & Lisle, A. (2008). A new heat load index for feedlot cattle. Journal of Animal Science, 86(1), 226-234. https://doi.org/10.2527/jas.2007-0305
  41. Giro, A., Pezzopane, J.R.M., Barioni Junior, W., Pedroso, A.F., Lemes, A.P., Botta, D., Romanello, N., Barreto, A.N., & Garcia, A.R. (2019). Behaviour and body surface temperature of beef cattle in integrat¬ed crop–livestock systems with or without tree shading. Science of the Total Environment, 684, 587-596. https://doi.org/10.1016/j.scito¬tenv.2019.05.377
  42. Gunn, K.M., Holly, M.A., Veith, T.L., Buda, A.R., Prasad, R., & Rotz, C.A. (2019). Projected heat stress challenges and abatement opportuni¬ties for U.S. milk production. PLoS One 14(3), e0214665. https://doi. org/10.1371/journal.pone.0214665
  43. He, G., Zhang, B., Yi, K., Chen, T., Shen, C., Cao, M., Wang, N., Zong, J., Wang, Y., Liu, K., Chang, F., Chen, X., Chen, L., Luo, Y., Meng, Y., Li, C., & Zhou, X. (2024). Heat stress-induced dysbiosis of the gut mi¬crobiota impairs spermatogenesis by regulating secondary bile acid metabolism in the gut. Science of the Total Environment, 937, 173305. https://doi.org/10.1016/j.scitotenv.2024.173305
  44. Hendriks, J., Mills, K.E., Sirovica, L.V., Sundermann, L., Bolton, S.E., & von Key¬serlingk, M.A.G. (2022). Public perceptions of potential adaptations for mitigating heat stress on Australian dairy farms. Journal of Dairy Science, 105(7), 5893-5908. https://doi.org/10.3168/jds.2022-21813
  45. Hendriks, S.J., Edwards, J.P., Shirley, A.K., Clark, C.E.F., Schütz, K.E., Verhoek, K.J., & Jago, J.G. (2025). Heat stress amelioration for pas¬ture-based dairy cattle: Challenges and opportunities. Animal Fron¬tiers, 15(2), 32-43. https://doi.org/10.1093/af/vfae043
  46. Hendriks, S.J., Phyn, C.V.C., Turner, S.A., Mueller, K.R., Kuhn-Sherlock, B., Donaghy, D.J., Huzzey, J.M., & Roche, J.R. (2019). Effect of weath¬er on activity and lying behaviour in clinically healthy grazing dairy cows during the transition period. Animal Production Science 60(1), 148. https://doi.org/10.1071/AN18569
  47. Herbut, P., Angrecka, S., & Walczak, J. (2018). Environmental parameters to assessing heat stress in dairy cattle: A review. International Journal of Biometeorology, 62, 2089-2097. https://doi.org/10.1007/s00484-018-1629-9
  48. Hill, T.M., Bateman, H.G. 2nd., Suarez-Mena, F.X., Dennis, T.S., & Schlot¬terbeck, R.L. (2016). Short communication: Changes in body tempera¬ture of calves up to 2 months of age as affected by time of day, age, and ambient temperature. Journal of Dairy Science, 99(11), 8867-8870. https://doi.org/10.3168/jds.2016-10994.
  49. Hitchman, S., Zobel, G., Schütz, K.E., Jago, J.G., Reed, C., Hay, E., Thomas, C., Edwards, J.P., & Verhoek, K.J. (2024). Updated method of estimat¬ing heat load for grazing dairy cattle. New Zealand Journal of Agricul¬tural Research, 68(6), 1611-1631. https://doi.org/10.1080/00288233.202 4.2396970
  50. Hristov, H. (2025). Using infrared thermography to study the impact of dangerous heat stress on thigh and udder temperature in dairy cows. Engineering Proceedings 104(1), 94. https://doi.org/10.3390/eng¬proc2025104094
  51. Idris, M., Uddin, J., Sullivan, M., McNeill, D, & Phillips, C. (2021). Non-Inva¬sive Physiological Indicators of Heat Stress in Cattle. Animals, 11(1), 71. https://doi.org/10.3390/ani11010071
  52. International Dairy Federation. (2025). Managing heat stress in dairy cattle. Bulletin of the IDF No. 534/2025. https://doi.org/10.56169/NFGC1866
  53. Islam, M.A., Lomax, S., Doughty, A.K., Islam, M.R., & Clark, C.E.F. (2020). Automated monitoring of panting for feedlot cattle: Sensor system accuracy and individual variability. Animals 10(9), 1518. https://doi. org/10.3390/ani10091518
  54. Islam, M.A., Lomax, S., Doughty, A.K., Islam, M.R., Jay, O., Thomson, P., & Clark, C.E.F. (2021). Automated monitoring of cattle heat stress and its mitigation. Frontiers in Animal Science 2, 737213. https://doi. org/10.3389/fanim.2021.737213
  55. Jara, I.E., Keim, J.P., & Arias, R.A. (2016). Behaviour, tympanic tempera¬ture and performance of dairy cows during summer season in south¬ern Chile. Archivos de Medicina Veterinaria 48(1), 113-118. http://dx.doi. org/10.4067/S0301-732X2016000100014
  56. Ji, B., Banhazi, T.M., Perano, K.M., Ghahramani, A., Bowtell, L., Wang, C., & Li, B. (2020). A review of measuring, assessing and mitigating heat stress in dairy cattle. Biosystems Engineering 199, 4-26. https://doi. org/10.1016/j.biosystemseng.2020.07.009
  57. Kappes, R., Knob, D.A., Scheid, A.L., Barreta, B.E., Perazzoli, L., Mendes, B.B., Alessio, D.R.M., & Neto, A.T. (2022). Rumination time, activity index, and productive performance of Holstein and crossbred Hol¬stein × Jersey cows exposed to different temperature-humidity in¬dexes. International Journal of Biometeorology 66, 791-801. https://doi. org/10.1007/s00484-021-02237-3
  58. Kendall, P.E., Nielsen, P.P., Webster, J.R., Verkerk, G.A., Littlejohn, R.P., & Matthews, L.R. (2006). The effects of providing shade to lactating dairy cows in a temperate climate. Livestock Science 103(1-2), 148–157. https://doi.org/10.1016/j.livsci.2006.02.004
  59. Kim, D.H., Kim, M.H., Kim, S.B., Son, J.K., Lee, J.H., Joo, S.S., Gu, B.H., Park, T., Park, B.Y., & Kim, E.T. (2020). Differential dynamics of the rumi¬nal microbiome of Jersey cows in a heat stress environment. Animals 10(7), 1127. https://doi.org/10.3390/ani10071127
  60. Koch, F., Albrecht, D., Gors, S., & Kuhla, B. (2021). Jejunal mucosa pro¬teomics unravel metabolic adaptive processes to mild chronic heat stress in dairy cows. Scientific Reports 11, 12484. https://doi.org/10.1038/ s41598-021-92053-x
  61. Koch, F., Reyer, H., Görs, S., Hansen, C., Wimmers, K., & Kuhla, B. (2024). Heat stress and feeding effects on the mucosa-associated and digesta microbiome and their relationship to plasma and digesta fluid me¬tabolites in the jejunum of dairy cows. Journal of Dairy Science 107(7), 5162-5177. https://doi.org/10.3168/jds.2023-24242
  62. Koch, F., Thom, U., Albrecht, E., Weikard, R., Nolte, W., Kuhla, B., & Kuehn, C. (2019). Heat stress directly impairs gut integrity and re¬cruits distinct immune cell populations into the bovine intestine. Pro¬ceedings of the National Academy of Sciences of the United States of America, 116(21), 10333-10338. https://doi.org/10.1073/pnas.1820130116
  63. Koltes, J.E., Koltes, D.A., Mote, B.E., Tucker, J., & Hubbell, D.S. (2018). Au¬tomated collection of heat stress data in livestock: New technologies and opportunities. Translational Animal Science, 2(3), 319-323. https:// doi.org/10.1093/tas/txy061
  64. Kökten, T.F., Hansmannel, N.C., Ndiaye, A.C., Heba, D., Quilliot, N., Dre¬umont, D., & Peyrin-Biroulet, L. (2021). Calorie restriction as a new treatment of inflammatory diseases. Advances in Nutrition 12, 1558-1570. https://doi.org/10.1093/advances/nmaa179
  65. Kraimi, N., Dawkins, M., Gebhardt-Henrich, S.G., Velge, P., Rychlik, I., Volf, J., Creach, P., Smith, A., Colles, F., & Leterrier, C. (2019). Influ¬ence of the microbiota-gut-brain axis on behaviour and welfare in farm animals: A review. Physiology & Behavior, 210, 112658. https://doi. org/10.1016/j.physbeh.2019.112658
  66. Lamp, O., Derno, M., Otten, W., Mielenz, M., Nürnberg, G., & Kuhla, B. (2015). Metabolic heat stress adaption in transition cows: Differences in macronutrient oxidation between late-gestating and early-lactating German Holstein dairy cows. PLoS One 10(5), e0125264. https://doi. org/10.1371/journal.pone.0125264
  67. Lane, D., Murdock, E., Genskow, K., Rumery Betz, C., & Chatrchyan, A. (2019). Climate change and dairy in New York and Wisconsin: Risk perceptions, vulnerability, and adaptation among farmers and advisors. Sustainability, 11(13), 33599. https://doi.org/10.3390/ su11133599
  68. Lees, J.C., Lees, A.M., & Gaughan, J.B. (2018a). Developing a heat load index for lactating dairy cows. Animal Production Science, 58(8), 1387-1391. https://doi.org/10.1071/AN17776
  69. Lees, J.C., Lees, A.M., & Gaughan, J.B. (2022). The influence of shade availability on the effectiveness of the Dairy Heat Load Index (DHLI) to predict lactating cow behavior, physiology, and production traits. International Journal of Biometeorology, 66, 289-299. https://doi. org/10.1007/s00484-021-02186-x
  70. Lees, A.M., Lees, J., Lisle, A., Sullivan, M., & Gaughan, J. (2018b). Effect of heat stress on rumen temperature of three breeds of cattle. Interna¬tional Journal of Biometeorology, 62, 207-215. https://doi.org/10.1007/ s00484-017-1442-x
  71. Lees, A.M., Sejian, V., Wallage, A.L., Steel, C.C., Mader, T.L., Lees, J.C., & Gaughan, J.B. (2019). The impact of heat load on cattle. Animals 9(6), 322. https://doi.org/10.3390/ani9060322
  72. Leliveld, L.M.C., Lovarelli, D., & Provolo, G. (2025). Dairy cow be¬haviour and physical activity as indicators of heat stress. Italian Jour¬nal of Animal Science, 24(1), 772–783. https://doi.org/10.1080/182805 1X.2025.2471545
  73. Li, Z., Fan, Y., Bai, H., Zhang, J., Mao, S., & Jin, W. (2023). Live yeast supplementation altered the bacterial community's composition and function in rumen and hindgut and alleviated the detrimental effects of heat stress on dairy cows. Journal of Animal Science, 101, skac410. https://doi.org/10.1093/jas/skac410
  74. Li, M., Wang, Z., Ma, Z., Wang, Y., Jia, H., Zhang, L., Chen, P., Mao, Y., & Yang, Z. (2025). Metagenomic analysis reveals microbial drivers of heat resistance in dairy cattle. Animal Microbiome, 7, 35. https://doi. org/10.1186/s42523-025-00399-8
  75. Mader, T.L., Davis, M.S., & Brown-Brandl, T. (2006). Environmental fac¬tors influencing heat stress in feedlot cattle. Journal of Animal Science, 84(3), 712-719. https://doi.org/10.2527/2006.843712x
  76. Mader, T.L., Johnson, L.J, & Gaughan, J.B. (2010). A comprehensive index for assessing environmental stress in animals. Journal of Animal Sci¬ence, 88(6), 2153-2165. https://doi.org/10.2527/jas.2009-2586
  77. Maia, G.G., Siqueira, L.C., Tomich, C.O.P., Camargo, T.R., Rodrigues, L.S.A., Menezes, J.P.P., Gonçalves, R.A., Oliveira Nogueira, R., Gar¬cia, L.A., & Pereira, L.G.R. (2020). Effects of heat stress on rumina¬tion activity in dairy cows. Livestock Science, 239, 104092. https://doi. org/10.1016/j.livsci.2020.104092
  78. McDonald, K., Goldhawk, C., & Proudfoot, K.L. (2020). Social rank in¬fluences drinking behaviour of dairy cows under heat stress. Applied Animal Behaviour Science, 224, 104947. https://doi.org/10.1016/j.ap¬planim.2020.104947
  79. Müschner-Siemens, T., Hoffmann, G., Ammon, C., & Amon, T. (2020). Daily rumination time of lactating dairy cows under heat stress condi¬tions. Journal of Thermal Biology, 88, 102484. https://doi.org/10.1016/j. jtherbio.2019.102484
  80. Nascimento, D.R., Azevedo, V.A.N., Ribeiro, R.P., Ximenes, G.O., Sil¬va, A.A., Barbalho, E.C., Barrozo, L.G., Chaves, S.C., Castro, M.S.M., Marcelino, E.C., Vaz da Silva, L.R.C., Batista, A.M., & Silva, J.R.V. (2025). Reproductive challenges in ruminants under heat stress: A review of follicular, oocyte, and embryonic responses. Animals, 15(15), 2296. https://doi.org/10.3390/ani15152296
  81. National Research Council. (1971). A guide to environmental research on an¬imals. National Academy of Sciences. https://www.nationalacademies. org/read/20608
  82. Nielsen, P.P., & Wredle, E. (2023). How Does the Provision of Shade during Grazing Affect Heat Stress Experienced by Dairy Cows in Swe¬den? Animals, 13(24), 3823. https://doi.org/10.3390/ani13243823
  83. Osei-Amponsah, R., Dunshea, F.R., Leury, B.J., Cheng, L., Cullen, B., Joy, A., & Chauhan, S.S. (2020). Heat stress impacts on lactating cows grazing Australian summer pastures on an automatic robotic dairy. Animals, 10(5), 869. https://doi.org/10.3390/ani10050869
  84. Pathirana, I.N., & Garcia, S.C. (2022). Detection of heat-shock protein 70 in cow’s milk using ELISA. Animal Production Science, 62(12), 1014–1019. https://doi.org/10.1071/AN21506
  85. Petersen, C., & Round, J.L. (2014). How changes in microbiota structure influence health. Cellular Microbiology, 16(7), 1024-1033. https://doi. org/10.1111/cmi.12308
  86. Pinto, S., Hoffmann, G., Ammon, C., & Amon, T. (2020). Critical THI thresh¬olds based on physiological parameters of lactating dairy cows. Journal of Thermal Biology, 88, 102523. https://doi.org/10.1016/j.jtherbio.2020.102523
  87. Polsky, L., & von Keyserlingk, M.A.G. (2017). Effects of heat stress on dairy cattle welfare. Journal of Dairy Science, 100(11), 8645–8657. https://doi. org/10.3168/jds.2017-12651
  88. Pontiggia, A., Holinger, M., Münger, A., Ammer, S., Dohme-Meier, F., & Keil, N.M. (2025). Mitigating heat stress in full-time grazing dairy cows in temperate cli¬mates: The impact of indoor housing during the hottest time of day. Journal of Dairy Science, 29, 100488. https://doi.org/10.1016/j.vas.2025.100488
  89. Razzaghi, A., Ghaffari, M.H., & Rico, D.E. (2023). The impact of environ¬mental and nutritional stresses on milk fat synthesis in dairy cows. Domestic Animal Endocrinology, 83 106784. https://doi.org/10.1016/j.domaniend.2022.106784
  90. Rizzatti, G., Lopetuso, L.R., Gibiino, G., Binda, C., & Gasbarrini, A. (2017). Proteobacteria: A common factor in human diseases. BioMed Research International, 2017, 9351507. https://doi.org/10.1155/2017/9351507
  91. Schütz, K.E., Cox, N.R., Cave, V.M., Huddart, F.J., & Tucker, C.B. (2023). Effects of changing milking and feeding times on the behaviour, body temperature, respiration rate and milk production of dairy cows on pasture. Applied Animal Behaviour Science, 261, 105895. https://doi. org/10.1016/j.applanim.2023.105895
  92. Setser, M.M.W., Cantor, M.C., & Costa, J.H.C. (2020). A comprehensive evaluation of microchips to measure temperature in dairy calves. Journal of Dairy Science, 103(10), 9290-9300. https://doi.org/10.3168/ jds.2019-17999
  93. Shephard, R.W., & Maloney, S.K. (2023). A review of thermal stress in cat¬tle. Australian Veterinary Journal, 101(11), 417-429. https://doi.org/10.1111/ avj.13275
  94. Stygar, A.H., Gómez, Y., Berteselli, G.V., Dalla Costa, E., Canali, E., Niemi, J.K., Llonch, P., & Pastell, M. (2021). A systematic review on commer¬cially available and validated sensor technologies for welfare assess¬ment of dairy cattle. Frontiers in Veterinary Science, 8, 634338. https:// doi.org/10.3389/fvets.2021.634338
  95. Tamminen, L., Båge, R., Åkerlind, M., & Olmos Antillón, G. (2024). Farm¬ers´ sense of the biological impact of extreme heat and seasonality on Swedish high-yielding dairy cows – A mixed methods approach. Preventive Veterinary Medicine, 224, 106131. https://doi.org/10.1016/j. prevetmed.2024.106131.
  96. Thom, E.C. (1959). The discomfort index. Weatherwise, 12, 57-59. https:// doi.org/10.1080/00431672.1959.9926960
  97. Toledo, I.M., Dahl, G.E., & de Vries, A. (2022). Dairy cattle management and housing for warm environments. Livestock Science, 255, 104802. https://doi.org/10.1016/j.livsci.2021.104802
  98. Tresoldi, G., Schütz, K.E., & Tucker, C.B. (2016). Assessing heat load in drylot dairy cattle: Refining on-farm sampling methodology. Journal of Dairy Science, 99(11), 8970-8980. https://doi.org/10.3168/jds.2016-11353
  99. Tresoldi, G., Schütz, K.E., & Tucker, C.B. (2020). Sampling strategy and measurement device affect vaginal temperature outcomes in lactat¬ing dairy cattle. Journal of Dairy Science, 103(6), 5414-5421. https://doi. org/10.3168/jds.2019-16667
  100. Tucker, C.B., Jensen, M.B., de Passillé, A.M., & Hänninen, L. (2021). Invited review: Lying time and the welfare of dairy cows. Journal of Dairy Sci¬ence, 104(1), 20-46. https://doi.org/10.3168/jds.2019-18074
  101. Tullo, E., Mattachini, G., Riva, E., Finzi, A., Provolo, G., & Guarino, M. (2019). Effects of Climatic Conditions on the Lying Behavior of a Group of Primiparous Dairy Cows. Animals, 9(11), 869. https://doi. org/10.3390/ani9110869.
  102. Um, K.H., Cho, S.R., Kang, S.S., Kim, U.H., Won, J.I., Jin, S., Park, M., Moon, S.J., Jang, G.S., Shokrollahi, B., Baek, Y.C., & Jang, S.S. (2024). Effects of heat stress on the physiological responses and vaginal microbiome of Hanwoo cows. South African Journal of Animal Science, 54(6), 708-722. https://doi.org/10.4314/sajas.v54i6.05
  103. van Erp-van der Kooij, E., Leenders, N.L.G., & Roelofs, J. (2024). Auto¬matic monitoring of body temperature in dairy cows using implanted sensors. In: Berckmans D, Tassinari P, Torreggiani D, eds. Proceed¬ings 11th European Conference on Precision Livestock Farming (ECPLF 2024), European Association for Precision Livestock Farming, p. 836-843. https://research.wur.nl/en/publications/automatic-monitor¬ing-of-body-temperature-in-dairy-cows-using-impl/
  104. Verhoek, K.J., Reed, C., McGowan, J., Cuthbert, S., & Jago, J.G. (2026). Un¬derstanding Farmer Perspectives of Cow Heat Stress in the Waikato and Canterbury Regions of New Zealand. New Zealand Journal of Ag¬ricultural Research, 69(1), e70024. https://doi.org/10.1002/jag2.70024
  105. Vieira, F. M., Soares, A. A., Herbut, P., Vismara, E. D., Godyń, D., Dos San¬tos, A. C., Lambertes, T. D., & Caetano, W. F. (2021). Spatio-Thermal Variability and Behaviour as Bio-Thermal Indicators of Heat Stress in Dairy Cows in a Compost Barn: A Case Study. Animals, 11(5), 1197. https://doi.org/10.3390/ani11051197.
  106. Vitali, A., Felici, A., Lees, A.M., Giacinti, G., Maresca, C., Bernabucci, U., Gaughan, J.B., Nardone, A., & Lacetera, N. (2020). Heat load increases the risk of clinical mastitis in dairy cattle. Journal of Dairy Science, 103(9), 8378-8387. https://doi.org/10.3168/jds.2019-17748
  107. Wang, Z., Liu, L., Pang, F., Zheng, Z., Teng, Z., Miao, T., Fu, T., Rushdi, H.E., Yang, L., Gao, T., Lin, F., & Liu, S. (2022b). Novel insights into heat tolerance using metabolomic and high-throughput sequencing analysis in dairy cows rumen fluid. Animal, 16(3), 100478. https://doi. org/10.1016/j.animal.2022.100478
  108. Wang, Z., Niu, K., Rushdi, H.E., Zhang, M., Fu, T., Gao, T., Yang, L., Liu, S., & Lin, F. (2022a). Heat stress induces shifts in the rumen bacteria and metabolome of buffalo. Animals, 12(10), 1300. https://doi.org/10.3390/ ani12101300
  109. Wang, X., Wang, Y., Feng, M., Li, J., Liu, Z., Fu, L., Zhang, N., Zhang, H., & Qin, J. (2025). Herbal formula alleviates heat stress by improving physiological and biochemical attributes and modulating the rumen microbiome in dairy cows. Frontiers in Veterinary Science, 12, 1558856. https://doi.org/10.3389/fvets.2025.1558856
  110. Wankar, A.K., Rindhe, S.N., & Doijad, N.S. (2021). Heat stress in dairy animals and current milk production trends, economics, and future perspectives: The global scenario. Tropical Animal Health and Produc¬tion, 53, 70. https://doi.org/10.1007/s11250-020-02541-x
  111. Welch, C.B., Ryman, V.E., Pringle, T.D., & Lourenco, J.M. (2022). Utilizing the gastrointestinal microbiota to modulate cattle health through the microbiome-gut-organ axes. Microorganisms, 10(7), 1391. https://doi. org/10.3390/microorganisms10071391
  112. Westin, R., Vaughan, A., de Passillé, A.M., DeVries, T.J., Pajor, E.A., Peller¬in, D., Siegford, J.M., Vasseur, E., & Rushen, J. (2016). Lying times of lactating cows on dairy farms with automatic milking systems and the relation to lameness, leg lesions, and body condition score. Journal of Dairy Science, 99(1), 551–562. https://doi.org/10.3168/jds.2015-9737
  113. Wickware, C.L., Johnson, T.A., & Koziol, J.H. (2020). Composition and diversity of the preputial microbiota in healthy bulls. Theriogenology, 145, 231-237. https://doi.org/10.1016/j.theriogenology.2019.11.002
  114. Woodward, S.J.R., Beukes, P.C., Edwards, J.P., Verhoek, K.J., Jago, J.G. & Zammit, C. (2024a). Prediction of regional heat stress risk for grazing dairy cows in a changing climate. agriRxiv [Preprint] 20240429911:1. https://doi.org/10.31220/agriRxiv.2024.00280.
  115. Woodward, S.J.R., Edwards, J.P., Verhoek, K.J., & Jago, J.G. (2024b). Iden¬tifying and predicting heat stress events for grazing dairy cows us¬ing rumen temperature boluses. JDS Communications, 5(5), 431-435. https://doi.org/10.3168/jdsc.2023-0482
  116. Woodward, S.J.R., Farrell, L.J., Burke, C.R., & Edwards, J.P. (2025). Mod¬eling shade use of grazing dairy cows using sensor-derived data and machine learning. Journal of Dairy Science, 108(10), 11151-11163. https:// doi.org/10.3168/jds.2025-26904
  117. Yan, G., Li, H., & Shi, Z. (2021). Evaluation of thermal indices as the indica¬tors of heat stress in dairy cows in a temperate climate. Animals, 11(8), 2459. https://doi.org/10.3390/ani11082459
  118. Zeineldin, M., Barakat, R., Elolimy, A., Salem, A.Z.M., Elghandour, M.M.Y., & Monroy, J.C. (2018). Synergetic action between the rumen microbi¬ota and bovine health. Microbial Pathogenesis, 124, 106-115. https://doi. org/10.1016/j.micpath.2018.08.038
  119. Zhao, S., Min, L., Zheng, N., & Wang, J. (2019). Effect of heat stress on bacterial composition and metabolism in the rumen of lactating dairy cows. Animals, 9(11), 925. https://doi.org/10.3390/ani9110925
  120. Zhuang, X., Chen, Z., Sun, X., Li, F., Luo, J., Chen, T., Xi, Q., Zhang, Y., & Sun, J. (2021). Fermentation quality of herbal tea residue and its application in fattening cattle under heat stress. BMC Veterinary Research, 17, 348. https://doi.org/10.1186/s12917-021-03061-y

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