Seventy-eight calves from Asturiana de los Valles, Retinta, and Rubia Gallega breeds, under extensive and intensive farm systems and animal mixing and non-mixing conditions, and during the transport and lairage in slaughterhouses, were studied. This research aimed to study the effect of breed, farm system and mixing conditions on serum biomarkers (cortisol, lactate, glucose, serum amyloid A, haptoglobin, and C-reactive protein) and their relationship pH_u at slaughter time, and to evaluate the response of the serum biomarkers of calves throughout fattening period. Moreover, this study aims to evaluate the response of the biomarkers in each breed during the fattening period. At slaughter time, cortisol and lactate were affected by BreedxFarm; Retinta showed the opposite pattern to the others and revealed the highest glucose in extensive farm systems. Rubia Gallega in mixing revealed the highest Amyloid A and haptoglobin. Extensive calves in mixing conditions showed the highest glucose. There was a relationship among the variables cortisol, lactate, Amyloid, and pH_u. Slaughter time was a major stressor, and the stress response was mainly affected by breed. At slaughter, several biomarkers should be considered.

中文翻译：

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犊牛血清生物标志物的应激评估及其与作为肉质指标的最终 pH 值的关系

研究了来自 Asturiana de los Valles、Retinta 和 Rubia Gallega 品种的 78 头小牛，在粗放和集约化农场系统以及动物混合和非混合条件下，以及在屠宰场的运输和围栏期间。本研究旨在研究品种、养殖系统和混合条件对血清生物标志物（皮质醇、乳酸、葡萄糖、血清淀粉样蛋白 A、结合珠蛋白和 C 反应蛋白）的影响及其关系 pH _u在屠宰时，并评估整个育肥期犊牛血清生物标志物的反应。此外，本研究旨在评估每个品种在育肥期间生物标志物的反应。在屠宰时，皮质醇和乳酸受到 BreedxFarm 的影响；Retinta 显示出与其他人相反的模式，并在粗放农场系统中显示出最高的葡萄糖。Rubia Gallega 在混合中显示出最高的淀粉样蛋白 A 和触珠蛋白。混合条件下的大牛犊表现出最高的葡萄糖。变量皮质醇、乳酸盐、淀粉样蛋白和 pH _u之间存在关系。屠宰时间是主要的应激源，应激反应主要受品种影响。在屠宰时，应考虑多种生物标志物。