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RESEARCH ARTICLE

Evaluating the impact of heat stress on milk quality in South Korea

Jing Zhang https://orcid.org/0000-0002-0889-039X A and Kyeong-Soo Jeong B *
+ Author Affiliations
- Author Affiliations

A Faculty of Business, Huaiyin Institute of Technology, Huai’an 223001, People’s Republic of China.

B Department of Economics, Konkuk University, Seoul 05029, Republic of Korea.

* Correspondence to: ksjeong@konkuk.ac.kr

Handling Editor: John Gaughan

Animal Production Science 62(15) 1501-1506 https://doi.org/10.1071/AN21592
Submitted: 7 December 2021  Accepted: 26 April 2022   Published: 6 June 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context: The probability of heat stress in South Korea is gradually increasing as a consequence of climate change. Although it is known that heat stress drives persistent negative effects on the lactation of dairy cattle, there is a lack of research on the effects of heat stress on milk quality in South Korea.

Aim: The aim of this study was to measure the influence of the temperature–humidity index (THI) on milk quality.

Methods: A non-parametric regression model was used to measure the influence of the THI on milk fat and milk protein. The data used in the model were obtained from observations of farmers’ management practises.

Key results: The concentrations of fat and protein in milk decreased when the THI was >65. In comparison with milk fat, milk protein was more significantly affected by heat stress.

Conclusions: A comparison of the THI values from 2001–2009 and 2010–2020 indicated that heat stress has occurred more frequently over time in South Korea. The concentrations of fat and protein in milk decrease when the THI exceeds 65.

Implications: Korean dairy farmers should build facilities that provide the optimal low and relatively dry conditions needed for dairy cattle to cope with heat stress and mitigate its impact on milk quality.

Keywords: climate change, dairy farm, heat stress, milk fat, milk protein, non-parametric regression, South Korea, temperature–humidity index.


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