Article

Metabolic and Metataxonomic Changes in Lactating Holstein Dairy Cows During the Transition from Heat Stress to the Recovery Period

Raniel Valencia1,2, Seon Ho Kim1, Janine Berdos1, Myung Hoo Kim3, Sung Sill Lee4, Sang Suk Lee1,*
Author Information & Copyright
1Ruminant Nutrition and Anaerobe Laboratory, Department of Animal Science and Technology,Sunchon National University, Suncheon 57922, Korea.
2College of Agriculture, Department of Animal Science, Central Luzon State University, Science City of Muñoz 3120, Philippines.
3Department of Animal Science, Pusan National University, Miryang 43241, Korea.
4Institute of Agriculture and Life Science (IALS), Gyeongsang National University, Jinju 52828, Korea.
*Corresponding Author: Sang Suk Lee, Ruminant Nutrition and Anaerobe Laboratory, Department of Animal Science and Technology,Sunchon National University, Suncheon 57922, Korea, Republic of. Phone: +82-61-750-3237. E-mail: rumen@scnu.ac.kr.

© Copyright 2024 Korean Society of Animal Science and Technology. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This study investigated the changes in rumen fermentation characteristics, blood parameters, and rumen microbial communities of Holstein dairy cows in the early lactation stage during heat stress conditions and subsequent recovery. This study aimed to fill the significant knowledge gaps regarding the recovery of dairy cattle from heat stress during the early stages of lactation. Metataxonomic analysis was used to identify potential biomarkers and metabolites associated with metabolic disease prediction. The temperature-humidity index was recorded on a dairy farm to define the heat stress and recovery periods.  Using the Bray-Curtis dissimilarity index, principal coordinate analysis revealed that both the heat stress and recovery periods affected the overall composition of the rumen bacterial community. The first three principal coordinates explained 33.00%, 16.60%, and 11.60% of the total variation, indicating the significant (p &lt; 0.01) influence of temperature changes on the dominance of rumen microbes and the rumen environment. However, alpha diversity measurements were unaffected in either period. Metataxonomic analysis (average relative abundance 2%) of cows in both periods revealed ten predominant genera: <italic>Prevotella</italic>, <italic>Ruminococcus</italic>, <italic>Selenomonas</italic>, <italic>Gilliamella</italic>, <italic>Duncaniella</italic>, <italic>Succiniclasticum</italic>, <italic>Paraprevotella</italic>, <italic>Bacteriodes</italic>, <italic>Lentimicrobium</italic>, and <italic>Treponema</italic>. During heat stress, significant alterations were observed in the levels of three organic acids, six fatty acids, and thirteen amino acids. Furthermore, heat stress caused a significant increase in blood serum HSP27 and HSP70 levels (both p &lt; 0.01), whereas blood serum glucose (p = 0.001) and blood urea nitrogen (p &lt; 0.001) decreased. Heat stress increased blood serum ketone concentrations, decreased cholesterol and blood urea nitrogen concentrations, and altered total protein, aspartate aminotransferase, and total bilirubin concentrations. The levels of blood serum minerals, such as calcium, phosphorus, and magnesium, as well as ruminal pH, ammonia-N, acetate, and butyrate, were not affected during either period. Heat stress influenced propionate (p=0.006) and total volatile fatty acids (p=0.030). Overall, heat stress during early lactation resulted in significant shifts within the rumen bacterial community structure, accompanied by corresponding changes in blood metabolite profiles.

Keywords: Early stage; Heat stress; Holstein dairy cows; Recovery period; Ruminal bacterial diversity