Ruminant Research Unit, Agroscope, Posieux, Switzerland; ETH Zurich, Animal Physiology, Institute of Agricultural Sciences, Zurich, Switzerland.
Ruminant Research Unit, Agroscope, Posieux, Switzerland.
Meat Sci. 2019 Dec;158:107892. doi: 10.1016/j.meatsci.2019.107892. Epub 2019 Jul 23.
The study used 81 young bulls, half of which were disbudded at 7 weeks of age. The effects of horn status during rearing and of acute physical and emotional stress just before slaughter on the physiological status at slaughter and subsequent meat quality were investigated. Bulls were reared in groups containing i) only bulls with horns, ii) only bulls without horns, or iii) mixed (half with, and half without horns). Bulls of each rearing condition were assigned to one of two slaughter conditions: with limited (LS) or with supplementary stress (SS). LS resulted in lower heart rates, stress hormone concentrations and carcass temperature, whereas SS resulted in faster post mortem pH decline and lower juiciness. Horned bulls from unmixed rearing groups had lower early pm temperature, shorter sarcomeres, and lower tenderness compared to disbudded bulls. Correlations and regression analysis revealed relationships between physiological indicators, mainly heart rate before slaughter, and meat quality, including water-holding capacity and indicators of proteolysis.
本研究使用了 81 头年轻公牛，其中一半在 7 周龄时进行去角。研究了饲养过程中角的状态以及屠宰前的急性生理和心理应激对屠宰时的生理状态和随后的肉质的影响。公牛被分组饲养，包含 i）只有有角的公牛，ii）只有无角的公牛，或 iii）混合（一半有角，一半无角）。每组公牛被分配到两种屠宰条件之一：有限应激（LS）或补充应激（SS）。LS 导致较低的心率、应激激素浓度和胴体温度，而 SS 导致更快的死后 pH 值下降和更低的多汁性。来自非混合饲养组的有角公牛的早期 pm 温度较低，肌节较短，嫩度较低，与去角的公牛相比。相关性和回归分析显示了生理指标与肉质之间的关系，主要是屠宰前的心率与保水性和蛋白水解指标有关。
