Abstract
Heat stress is an important issue in dairy cattle feeding management affecting summer health and economic efficiency. This experiment combined 16S rDNA sequencing(3,864,982 tags, 30 sequencing data), metagenomic sequencing(1,269,441,128 reads, 18 sequencing data), metabolomics analysis(72 sequencing data) and blood index analysis. Ten cows in each animal type (growing heifers, heifers, and lactating cows) were selected for sample collection in April and August. Here, we characterized both the changes in metabolites, rumen microbial communities and their functional potential and the effects of heat stress on serum biochemical, immune, oxidative stress, and hormonal indices derived from rumen fluid and serum samples from cows during different growth stages and in different climates. The generated data expand the resources for the rumen microbiome related to heat stress and age and provide useful datasets for research on developing therapeutic strategies to achieve high summer milk production in cows. These datasets will help researchers study the effects of heat stress on the physiological metabolism of Holstein cows and the time-dependent changes associated with growth stages.