Wang Shujie, Liu Mohan, Tian Da, Su Mu, Li Qiao, Li Zhen, Zhou Zhenlei
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
J Poult Sci. 2019 Jul 25;56(3):159-165. doi: 10.2141/jpsa.0180094.
Raman spectroscopy has been widely applied in the analysis of biological tissues. In this study, beak cuticle was studied to investigate its compositional and secondary structural changes during the laying period and aging of laying hens. The analysis revealed markedly increased contents of amide I and amino acids (phenylalanine and tyrosine) within the beak during the intense laying period from 17 to 20 weeks. In addition, -helical protein was also gradually synthesized in this period. The relative area ratio of 1003/1448 cm (assigned to the vibrations of phenylalanine and organic C-H respectively) was confirmed as an excellent indicator for estimating the start of the laying period. This ratio increased from 0.36 to 0.42 from 17 to 20 weeks. The Raman peak at 1156 cm was assigned to carotenoids in the beak. The intensities of the 1156 cm peak significantly decreased during aging. The area ratio of 1156/1448 cm was successfully applied to estimate ages (still within the laying period) of laying hens. This study shows the potential of using Raman spectroscopy to quantify ages and laying period of birds.
拉曼光谱已广泛应用于生物组织分析。在本研究中，对蛋鸡喙角质层进行研究，以探讨其在产蛋期和衰老过程中的成分及二级结构变化。分析显示，在17至20周的产蛋高峰期，喙内酰胺I和氨基酸（苯丙氨酸和酪氨酸）含量显著增加。此外，在此期间α-螺旋蛋白也逐渐合成。1003/1448 cm（分别对应苯丙氨酸和有机C-H的振动）的相对面积比被确认为估算产蛋期开始的优良指标。该比值在17至20周从0.36增至0.42。1156 cm处的拉曼峰归属于喙中的类胡萝卜素。在衰老过程中，1156 cm峰的强度显著降低。1156/1448 cm的面积比成功用于估算蛋鸡（仍处于产蛋期）的年龄。本研究展示了利用拉曼光谱量化鸟类年龄和产蛋期的潜力。
