Disease & heat resistance

Physiological patterns underlying behavioral traits in Avileña-Negra Ibérica calves under heat stress

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Abstract

Climate change is bringing new challenges to livestock, particularly to those under extensive conditions having to face limited access to feed and water resources, challenges from feral species in addition to heat stress (HS). Coping style, defined as a coherent set of behavioral and physiological responses to stress, can be viewed as an indicator of general or specific resilience. In farm animals, particularly in beef cattle, it is not well known whether animals with different behavioral characteristics also differ in their metabolomic profiles under stress, in this case HS. The aim of this study was to compare the metabolomic profiles of low-reactivity (LR) and high-reactivity (HR) calves under HS and to identify the metabolites and pathways that distinguish these groups as a tool to define coping style as a resilience phenotype. Plasma samples were collected in late July from 53 male Avileña-Negra Ibérica calves. Temperament was characterized by chute-exit behavior. Calves were assigned to the low reactivity group (LR) if they exited the chute walking, and to the high reactivity group (HR) otherwise. Metabolomic data were provided by Metabolon's untargeted mass spectrometry platform. Metabolites annotated as xenobiotics and those with extreme values were removed. Each metabolite was analyzed using a linear model, and those showing significant effects of body weight were corrected for this factor. A partial least squares discriminant analysis (PLS-DA) was used to explore metabolic differences between groups, and metabolites with a variable importance in projection greater than 1 were considered relevant. These selected metabolites were then used for pathway enrichment analysis in MetaboAnalyst 6.0. The PLS-DA showed a separation between LR and HR, with partial overlap, suggesting that reactivity is associated with distinct (but not exclusive) metabolic patterns. LR calves showed higher levels of taurine, a metabolite linked to cellular protection and osmotic balance. In line with this, pathway analysis indicated enrichment of amino-acid and nitrogen pathways, taurine-hypotaurine metabolism, and pathways related to maintenance and anabolic processes. In contrast, HR calves showed higher levels of energy-related metabolites, such as lactate and long-chain acylcarnitines. Consistently, HR calves were enriched in pathways related to energy turnover, glycolysis and pyruvate metabolism, nitrogen exchange, and lipid metabolism. Tryptophan-related pathways were also present in this group. Overall, these results suggest that metabolic differences associated with differences in temperament are worth pursuing to define coping style of individuals facing HS and therefore to define a new phenotype of resilience. Acknowledgments. This work was supported by Re-Livestock (HE-Re-Livestock - grant agreement No. 101059609) and PID2020-113913RR-C31. The first author is funded by the predoctoral grant PRE2021-098165. We thank the Real Asociación de Raza Avileña-Negra Ibérica for their support during the experimental work.

Keywords: 2026

How to Cite:

López-Martínez, J., Reinoso-Peláez, E., Carabaño, M., Ramón, M., Meneses, C., González, C., Hernández-Pumar, A. & Díaz, C., (2026) “Physiological patterns underlying behavioral traits in Avileña-Negra Ibérica calves under heat stress”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286419. doi: https://doi.org/10.31274/wcgalp.23996

Rights: 1