Control of blood retinol levels in cattle during fattening is important in the production of marbled beef. However, it is difficult to easily measure the blood retinol concentration in the field. In this study, we attempted to develop an analysis method that does not require blood cell separation and uses a compact fluorescence analyzer that can be carried around as a preliminary system for measuring blood retinol concentration in the field. This system was used to monitor blood retinol levels in 12 fattening cattle (14 to 27 months old) and demonstrated a strong correlation (r = 0.78) with the results obtained by the standard high-performance liquid chromatography (HPLC) method. Stronger correlations (r = 0.87) were obtained until the cattle were 24 months of age. These results suggest that higher correlations can be expected to be obtained by improving the robustness of the extraction system. Refinements for practical use need to be considered, but whole blood extraction and the vitamin A analyzer that was developed show potential to be used for on-farm monitoring of retinol levels.

中文翻译：

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牛血视黄醇水平快速分析初步系统

在肥育过程中控制牛的血液视黄醇水平对于大理石纹牛肉的生产很重要。然而，很难在现场轻松测量血液中的视黄醇浓度。在本研究中，我们尝试开发一种不需要血细胞分离的分析方法，并使用可随身携带的紧凑型荧光分析仪作为现场测量血液视黄醇浓度的初步系统。该系统用于监测 12 头育肥牛（14 至 27 个月大）的血液视黄醇水平，并证明 与标准高效液相色谱 (HPLC) 方法获得的结果具有很强的相关性 ( r = 0.78)。更强的相关性 ( r = 0.87) 直到牛 24 个月大。这些结果表明，通过提高提取系统的鲁棒性，可以获得更高的相关性。需要考虑实际使用的改进，但全血提取和开发的维生素 A 分析仪显示出可用于农场视黄醇水平监测的潜力。