Analysis of CircRNA Expression in Peripheral Blood of Holstein Cows in Response to Heat Stress

Abstract

The present study aimed to identify key circRNAs and pathways associated with heat stress in blood samples of Holstein cows, which will provide new insights into the molecular mechanisms driving heat stress in cows. Hence, we evaluated changes in milk yield, rectal temperature, and respiratory rate of experimental cows between heat stress (summer) and non-heat stress (spring) conditions with two comparisons, including Sum1 vs. Spr1 (same lactation stage, different individuals, 15 cows per group) and Sum1 vs. Spr2 (same individual, different lactation stages, 15 cows per group). Compared to both Spr1 and Spr2, cows in the Sum1 group had a significantly lower milk yield, while rectal temperature and respiratory rate were significantly higher (p < 0.05), indicating that cows in the Sum1 group were experiencing heat stress. In each group, five animals were chosen randomly to undergo RNA-seq. The results reveal that 140 and 205 differentially expressed (DE) circRNAs were screened in the first and second comparisons, respectively. According to the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, these DE circRNAs were mainly enriched in five signaling pathways, including choline metabolism, the PI3K/AKT signaling pathway, the HIF-1 signaling pathway, the longevity-regulating pathway, and autophagy. Then, we obtained the top 10 hub source genes of circRNAs according to the protein–protein interaction networks. Among them, ciRNA1282 (HIF1A), circRNA4205 (NR3C1), and circRNA12923 (ROCK1) were enriched in multiple pathways and identified as binding multiple miRNAs. These key circRNAs may play an important role in the heat stress responses of dairy cows. These results provide valuable information on the involvement of key circRNAs and their expression pattern in the heat stress response of cows.

Characterization of the Temperament and Reactivity of Nelore Cattle (Bos indicus) Associated with Behavior Scores during Corral Management in the Humid Tropics

“…Factors such as wind and time of exposure to sunlight can influence the temperature variation [ 4 , 63 ]. High RT and BST values in the head and flank infrared temperature and rump infrared temperature regions in the traditional system explain the relationship between exposure to direct solar radiation and the physiological mechanism of heat dissipation [ 64 , 65 ].…”

“…On the other hand, the positive correlation between RT and RR suggests that there is a relationship between physiological variables; as RT increases, RR will also increase, suggesting a coordinated response by the body as a way of trying to regulate body temperature [ 65 , 73 , 74 ].…”

Understanding Circular RNAs in Health, Welfare, and Productive Traits of Cattle, Goats, and Sheep

“…Zhang et al (2023) [ 43 ] conducted a comprehensive investigation into the impact of heat stress on key biological processes and the potential involvement of circRNAs in the heat stress response. Their study focused on discerning circRNA expression profiles in peripheral blood samples of cows during heat stress, revealing significant alterations.…”

“…Therefore, recognizing the imperative to address the adverse impacts of heat stress, numerous studies are exploring the involvement of circRNAs in cattle subjected to heat stress. [43] conducted a comprehensive investigation into the impact of heat stress on key biological processes and the potential involvement of circRNAs in the heat stress response. Their study focused on discerning circRNA expression profiles in peripheral blood samples of cows during heat stress, revealing significant alterations.…”