Effects of THI changes on milk production and composition of three dairy cattle farms in Mugello from 2010 to 2018: a preliminary study

Submitted 2020-07-03 | Accepted 2020-09-09 | Available 2020-12-01 https://doi.org/10.15414/afz.2020.23.mi-fpap.167-173 Global warming is already affecting several areas and a further increase of 1.5°C is expected by 2050. Dairy cattle are particularly sensitive to high temperature. So, the aim of this study was to examine the effect of temperature-humidity index (THI) on milk traits, considering changes of climatic parameters in the different seasons from 2010 to 2018. The study was conducted in 3 farms located in a hilly-mountainous area of Tuscany, the Mugello, situated from 220 to 450 m above sea level. Data on average daily milk yield and composition were monthly collected in the 3 farms from 2010 to 2018, while climatic parameters were recorded by a climatic station located in the area of the farms. As regards the climatic parameters, no significant variations have been observed in the last decade. The THI calculated thanks to the recording of temperature and humidity of the weather station, during the warmest months, was high enough to cause heat stress. The milk quality traits declined when THI increased. In conclusion, there was not any evidence that global warming has been affecting Mugello, but, despite its altitude, high THI usually reached during spring and summer seasons are already high enough to cause heat stress and a further increase could worsen farm productivity. Keywords: climate change, milk quality, heat stress, dairy cow References Amamou, H. et al. (2019). Thermotolerance indicators related to production and physiological responses to heat stress of Holstein cows. Journal of Thermal Biology, 82, 90–98. https://doi.org/10.1016/j.jtherbio.2019.03.016 Andre, G. et al. (2011). Quantifying the effect of heat stress on daily milk yield and monitoring dynamic changes using an adaptive dynamic model. Journal of Dairy Science, 94(9), 4502–4513. https://doi.org/10.3168/jds.2010-4139 Bartolini, G. et al. (2012). Mediterranean warming is especially due to summer season. Theoretical and Applied Climatology, 107, 279–295. https://doi.org/10.1007/s00704-011-0481-1 Baumgard, L. H. and Rhoads, R. P. (2007). The effects of hyperthermia on nutrient partitioning. In: Proceedings of Cornell Nutrition Conference, Ithaca, New York, 93–104. Bertocchi, L. et al. (2014). Seasonal variations in the composition of Holstein cow’s milk and temperature-humidity index relationship. Animal, 8(4), 667–674. https://doi.org/10.1017/S1751731114000032 Bohmanova, J., Misztal, I. and Cole, J. B. (2007). Temperature-humidity indices 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 Bouraoui, R. et al. (2002). The relationship of temperature-humidity index with milk production of dairy cows in a Mediterranean climate. Animal Research, 51(6), 479–491. https://doi.org/10.1051/animres:2002036 Das, R. et al. (2016). Impact of heat stress on health and performance of dairy animals: A review. Veterinary World, 9(3), 260–268. https://doi.org/10.14202/vetworld.2016.260-268 Fabris, T. F. et al. (2019). Effect of heat stress during early, late, and entire dry period on dairy cattle. Journal of Dairy Science, 102(6), 5647–5656. https://doi.org/10.3168/jds.2018-15721 Gauly, M. and Ammer, S. (2020). Review: Challenges for dairy cow production systems arising from climate changes. Animal, 14(S1), S196–S203. https://doi.org/10.1017/S1751731119003239 Hossein-Zadeh, N. G., Mohit, A. and Azad, N. (2013). Effect of temperature-humidity index on productive and reproductive performances of Iranian Holstein cows. Iranian Journal of Veterinary Research 14(2), 106-112. https://dx.doi.org/10.22099/ijvr.2013.1583 Herbut, P., Angrecka, S. and Godyn, D. (2018). Effect of the duration of high air temperature on cow’s milking performance in moderate climate conditions. Annals of Animal Science, 18(1), 195–207. https://doi.org/10.1515/aoas-2017-0017 Javed, K. et al. (2004). Environmental factors affecting milk yield in Friesian cows in Punjab, Pakistan. Pakistan Veterinary Journal, 24, 4-7. Polsky, L. and von Keyserlingk, M. A. G. (2017). Invited review: Effects of heat stress on dairy cattle welfare. Journal of Dairy Science, 100(11), 8645–8657. https://doi.org/10.3168/jds.2017-12651 Renaudeau, D. et al. (2012). Adaptation to hot climate and strategies to alleviate heat stress in livestock production. Animal, 6(5), 707–728. https://doi.org/10.1017/S1751731111002448 Rhoads, M. L. et al. (2009). Effects of heat stress and plane of nutrition on lactating Holstein cows: I. Production, metabolism, and aspects of circulating somatotropin. Journal of Dairy Science, 92(5), 1986–1997. https://doi.org/10.3168/jds.2008-1641 Rojas-Downing, M. M. et al. (2017). Climate change and livestock: Impacts, adaptation, and mitigation. Climate Risk Management, 16, 145–163. https://doi.org/10.1016/j.crm.2017.02.001 Silanikove, N. and Koluman, D. N. (2015). Impact of climate change on the dairy industry in temperate zones: Predications on the overall negative impact and on the positive role of dairy goats in adaptation to earth warming. Small Ruminant Research, 123(1), 27–34. https://doi.org/10.1016/j.smallrumres.2014.11.005 Spiers, D. E., et al. (2004). Use of physiological parameters to predict milk yield and feed intake in heat-stressed dairy cows. Journal of Thermal Biology, 29(7-8 SPEC. ISS.), 759–764. https://doi.org/10.1016/j.jtherbio.2004.08.051 Thornton, P. K. et al. (2009). The impacts of climate change on livestock and livestock systems in developing countries: A review of what we know and what we need to know. Agricultural Systems, 101(3), 113–127. https://doi.org/10.1016/j.agsy.2009.05.002 Zampieri, M. et al. (2016). Global assessment of heat wave magnitudes from 1901 to 2010 and implications for the river discharge of the Alps. Science of the Total Environment, 571, 1330–1339. https://doi.org/10.1016/j.scitotenv.2016.07.008