Clinic for Ruminants with Ambulatory and Herd Health Services, Centre for Clinical Veterinary Medicine, LMU Munich, Sonnenstrasse 16, 85764, Oberschleissheim, Germany.
BMC Vet Res. 2024 May 24;20(1):226. doi: 10.1186/s12917-024-04010-1.
The recognition of pain is a major problem in cattle, as they are stoic animals which strongly mask their pain. Among objective parameters to assess pain in cattle is substance P (SP), a neurotransmitter which is involved in the pain pathways. Research about SP concentration in calves focus on painful procedures, such as castration and dehorning. Basic research work is lacking; evaluation of SP concentrations in healthy calves and possible differences between sexes have not been published yet. The objectives of this study were to (1) describe SP concentrations in healthy male and female calves of the German Simmental breed to establish benchmarks of orientation, (2) compare SP concentrations between male and female calves, and (3) assess differences in SP concentrations between calves and adult cows. A total of 44 male and 49 female calves aged 14 to 21 days (17.1 ± 2.2 days) were included in this study. Blood samples were taken at 06:00 a.m. from the jugular vein, followed by a clinical examination. SP concentrations were analyzed using a commercial ELISA kit. Differences in SP concentrations according to laboratory parameters, and correlation of SP concentrations with different parameters were assessed.
Median SP concentrations in the blood plasma were 516 pg/ml (Interquartile Range 320 pg/ml, range 229-1615 pg/ml) in calves. Median SP concentrations differed significantly between male and female calves (554 pg/ml for male, and 489 pg/ml for female calves, respectively). There was no significant difference in animals with laboratory findings within reference ranges and those with mild deviations from reference ranges. There was a positive correlation between SP concentrations and leucocyte count, which was significant. SP concentrations were significantly lower in calves compared with a dataset of adult cows, which has been published previously.
Due to the high interindividual differences in SP concentrations, it is hard to establish benchmarks for orientation. Sex has a significant influence on SP concentrations. Research work should preferably be done in animals of the same sex. Also, animals should be within the same age range (adults or calves), as age seems to have an influence on SP concentrations.
在牛中，识别疼痛是一个主要问题，因为它们是坚韧的动物，会强烈掩盖自己的疼痛。评估牛疼痛的客观参数之一是 P 物质（SP），一种参与疼痛途径的神经递质。关于小牛 SP 浓度的研究集中在疼痛程序上，例如去势和去角。基本研究工作缺乏；尚未发表关于健康小牛 SP 浓度的评估以及性别之间可能存在的差异的研究。本研究的目的是：（1）描述德国西门塔尔种公牛和母牛的健康小牛的 SP 浓度，以建立基准，（2）比较公牛和母牛的 SP 浓度，（3）评估小牛和成年牛之间的 SP 浓度差异。本研究共纳入 44 头 14 至 21 日龄（17.1±2.2 日龄）的雄性和 49 头雌性小牛。早上 6 点从颈静脉采集血样，然后进行临床检查。使用商业 ELISA 试剂盒分析 SP 浓度。根据实验室参数评估 SP 浓度的差异，以及 SP 浓度与不同参数的相关性。
小牛血液中的 SP 浓度中位数为 516 pg/ml（四分位距 320 pg/ml，范围 229-1615 pg/ml）。雄性和雌性小牛的 SP 浓度中位数差异显著（雄性小牛为 554 pg/ml，雌性小牛为 489 pg/ml）。实验室指标在参考范围内和轻度偏离参考范围的动物之间没有显著差异。SP 浓度与白细胞计数呈正相关，具有统计学意义。与之前发表的成年牛数据集相比，小牛的 SP 浓度显著降低。
由于 SP 浓度的个体间差异很大，因此很难建立基准。性别对 SP 浓度有显著影响。研究工作最好在同一性别动物中进行。此外，动物应在相同的年龄范围内（成年或小牛），因为年龄似乎对 SP 浓度有影响。
