# Hematological, Enzymatic, and Endocrine Response to Intense Exercise in Lidia Breed Cattle During the Roping Bull Bullfighting Celebration

## TL;DR

This study measures stress and muscle damage in Lidia bulls during bullfighting events, finding significant but tolerable physiological changes.

## Contribution

The first comprehensive physiological assessment of Lidia cattle during bullfighting celebrations, providing baseline data for animal welfare evaluation.

## Key findings

- Bulls showed significant increases in stress hormones, white blood cells, and muscle enzymes after intense exercise.
- All measured physiological changes remained within normal ranges for healthy cattle.
- The study establishes baseline data for evaluating animal welfare in bullfighting events.

## Abstract

Traditional “Roping Bull” celebrations across Spain involve fighting bulls running continuously for 45 min while being chased by participants. Despite their cultural importance, there has been growing public concern about whether these events cause excessive stress or harm to the animals involved. This research aimed to conduct the first comprehensive scientific study to objectively measure the stress experienced by bulls during these popular celebrations, providing factual evidence to inform welfare discussions. We studied 53 bulls from different Spanish regions by collecting blood samples immediately before and after their participation in roping bull events. We analyzed stress indicators in their blood. The bulls showed significant physiological responses, including elevation of stress hormones, white blood cells, and muscle enzymes. Importantly, despite being substantial, all measured changes remained within normal ranges that healthy cattle can safely tolerate. While roping bull events do cause measurable stress to the animals, the bulls’ robust physiology allows them to handle these challenges without exceeding their natural adaptive capacity. This research provides the first scientific foundation for evidence-based animal welfare policies. The findings enable veterinarians, event organizers, regulatory authorities, and the public to make informed decisions about balancing cultural preservation with modern animal welfare standards.

The Lidia cattle breed is featured in several traditional popular bullfighting festivals throughout Spain, including the “Toro de Cuerda” event, in which the animals are subjected to intense physical exercise. However, the physiological impact and welfare implications of these activities remain poorly characterized. This study aimed to evaluate the stress response and muscle damage in Lidia breed bulls during roping bull celebrations through comprehensive blood analysis. Blood samples were collected from 53 adult male Lidia bulls before and after a standardized 45 min continuous running exercise during traditional roping bull events in four Spanish autonomous regions. Hematological parameters, muscle enzymes (creatine kinase, lactate dehydrogenase, lactate), and stress hormones (cortisol and ACTH) were analyzed. Significant increases (p < 0.05) were observed in leukocytes, lymphocytes, monocytes, eosinophils, neutrophils, erythrocytes, hematocrit, hemoglobin, and post-exercise platelets. Muscle enzymes showed marked elevations, with creatine kinase increasing up to 10-fold above baseline values. Stress hormones, cortisol and ACTH, also demonstrated significant increases. Despite the magnitude of these changes, all parameters remained within established reference ranges for the bovine species. This study provides the first physiological assessment of Lidia cattle during popular bullfighting celebrations, establishing baseline data for evidence-based welfare evaluation and management protocols.