The objective of this current work was to determinate the effect of high temperatures on milk production of dairy cows in southern Slovakia in the year 2015. The hypotheses that milk production is influenced by the altitude and cooling were tested. Production data included 227,500 test-day records belonging to 34 Holstein breed herds situated in lowlands, 115 to 150 m above sea level (ASL) and kept in free-stall housing. Dairy farms were classified into groups based on cooling system. The first group of cows (19 herds) was cooled evaporative (foggers) and forced ventilation, and the second group (15 herds) was using cooled only forced ventilation (automatically controlled fans in housing and feeding areas). During the period from May to September, 36 summer and 22 tropical days were recorded, 37 days had a mean thermal humidity index value above 72.0, and on 34 days we recorded mean values above 78.0. The highest milk yields were recorded at the altitude 1 (115 m ASL) (9219.0 kg year-1; 10327.0 kg year-1) and the lowest at the altitude 2 (126 m ASL) (7598.7 kg year-1; 8470.21 kg year-1) (P < 0.001). Dairy cows cooled evaporative milked significantly more milk than cows cooled only with forced air flow (9650.4 kg vs. 8528.0 kg; P < 0.001). Fat and protein production differed also significantly (364.0 kg vs. 329.5 kg, P < 0.001; 312.2 kg vs. 279.7 kg, P < 0.001). It can be concluded that not only heat stress but also location farm above sea level can affect milk production. Evaporative cooling associated with increased air velocity is the appropriate protection against high temperatures.

Ministry of Agriculture and Rural Development of the Slovak Republic Bratislava Slovakia

National Agricultural and Food Centre Research Institute of Animal Production Nitra Hlohovecka 2 951 41 Luzianky Slovakia

Research Institute of Animal Production Praha Uhrineves Czech Republic

South Bohemia University Ceske Budejovice Czech Republic

The Breeding Services of the Slovak Republic Bratislava Slovakia

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J Dairy Sci. 2006 Apr;89(4):1244-53 PubMed

Animal. 2010 Jul;4(7):1167-83 PubMed

Int J Biometeorol. 2012 Mar;56(2):287-95 PubMed

J Vet Diagn Invest. 2013 Mar;25(2):210-8 PubMed

J Anim Sci. 1998 Oct;76(10):2671-7 PubMed

J Dairy Sci. 2011 Jul;94(7):3376-86 PubMed

J Dairy Sci. 2014;97(1):471-86 PubMed

Br J Nutr. 2003 Mar;89(3):399-408 PubMed

J Dairy Sci. 2013 Mar;96(3):1844-55 PubMed

Animal. 2012 May;6(5):707-28 PubMed

Trop Anim Health Prod. 2010 Dec;42(8):1763-70 PubMed

J Anim Sci. 1982 Feb;54(2):309-19 PubMed

J Dairy Sci. 2009 May;92(5):1986-97 PubMed

Animals (Basel). 2019 Apr 24;9(4): PubMed

J Anim Sci. 2015 Oct;93(10):4714-20 PubMed

Theriogenology. 2015 Sep 15;84(5):659-66 PubMed

Physiol Rev. 1991 Oct;71(4):1135-72 PubMed

J Vet Diagn Invest. 2012 Sep;24(5):867-77 PubMed

J Exp Biol. 1995 Jul;198(Pt 7):1499-507 PubMed

J Dairy Sci. 2017 Nov;100(11):8645-8657 PubMed

J Anim Sci. 2012 Jul;90(7):2152-8 PubMed

J Dairy Sci. 2012 Jul;95(7):3736-42 PubMed

Int J Biometeorol. 2018 Dec;62(12):2089-2097 PubMed

J Dairy Sci. 2016 Jul;99(7):5837-5843 PubMed

J Dairy Sci. 2017 Dec;100(12):10367-10380 PubMed

Int J Biometeorol. 2014 Aug;58(6):1225-36 PubMed

Animal. 2018 Dec;12(s2):s431-s444 PubMed

Int J Biometeorol. 2012 Nov;56(6):993-9 PubMed

J Dairy Sci. 2015 Jul;98(7):4572-9 PubMed

Trends Ecol Evol. 2007 Nov;22(11):569-74 PubMed

Int J Biometeorol. 2013 Mar;57(2):299-306 PubMed

J Anim Sci. 2008 Jan;86(1):226-34 PubMed

J Anim Sci. 1999;77 Suppl 2:21-35 PubMed

J Anim Sci. 2018 Sep 7;96(9):3599-3605 PubMed

J Dairy Sci. 2011 Aug;94(8):4129-39 PubMed

Animals (Basel). 2017 May 02;7(5): PubMed

J Therm Biol. 2018 Oct;77:24-37 PubMed

Int J Biometeorol. 1999 Apr;42(4):183-8 PubMed

Nature. 2003 Jan 2;421(6918):37-42 PubMed

Int J Biometeorol. 2004 Feb;48(3):142-8 PubMed

J Dairy Sci. 2016 May;99(5):3798-3814 PubMed

J Anim Sci. 2006 Mar;84(3):712-9 PubMed

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