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¿Podría el cortisol del pelo en ganado en libertad ser un indicador de los patrones de depredación de los lobos?
Marta Rafael1, Eliana Fonseca2, Nuno Santos3,4
1Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, 4050-313 Porto, Portugal.
Conservation physiology
|January 30, 2026
Resumen
Los lobos grises atacan al ganado, lo que provoca conflictos entre humanos y fauna silvestre. La concentración de cortisol en el pelo (HCC) en el ganado fue menor en los atacados por lobos, lo que sugiere que el riesgo de depredación no siempre significa un mayor estrés.
Área de la Ciencia:
- Ecología de la vida silvestre
- Fisiología animal
- Biología de la conservación
Sus antecedentes:
- Los lobos grises (Canis lupus) atacan al ganado, lo que genera conflictos entre humanos y lobos y afecta los esfuerzos de conservación de lobos.
- El cortisol, una hormona del estrés, es un biomarcador potencial para comprender la dinámica depredador-presa.
Objetivo del estudio:
- Investigar si la concentración de cortisol en el pelo (HCC) puede servir como biomarcador para la selección individual de presas por parte de lobos grises que atacan al ganado (Bos taurus).
Principales métodos:
- Se midió la concentración de cortisol en muestras de pelo de ganado vivo y depredado por lobos mediante ensayos de inmunoabsorción ligados a enzimas.
- Se utilizaron modelos lineales mixtos para analizar los efectos de la edad, el sexo y la disponibilidad de alimentos en la HCC, considerando la granja como un efecto aleatorio.
Principales resultados:
- El ganado depredado por lobos exhibió una HCC significativamente menor en comparación con el ganado vivo.
- La HCC fue menor en el ganado subadulto que en los adultos.
- La HCC se correlacionó negativamente con la disponibilidad de alimentos en el ganado adulto, pero no en el subadulto.
Conclusiones:
- El riesgo de depredación puede no correlacionarse directamente con el estrés fisiológico a largo plazo en el ganado.
- El ganado con mayor estrés crónico (mayor HCC) podría mostrar comportamientos antipredatorios más efectivos.
- La disponibilidad de alimentos influye en el comportamiento de pastoreo del ganado, lo que podría aumentar los encuentros con lobos y afectar los patrones de depredación.
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