Zhao R, Xu G Y, Liu Z Z, Li J Y, Yang N
College of Animal Science and Technology, China Agricultural University, Beijing 100094, P R China.
Poult Sci. 2006 Mar;85(3):546-9. doi: 10.1093/ps/85.3.546.
Biliverdin is an important pigment in the eggshell of chickens and other avian species. Determination of the biosynthesis site for biliverdin is essential for understanding the biochemical process and genetic basis of eggshell pigmentation. Either blood or the shell gland could be the biosynthesis site of eggshell biliverdin. A segregation population with full-sib sisters genotyped Oo and oo, which laid blue-shelled eggs and light brown eggs, respectively, was constructed in a native Chinese chicken breed. Ultraviolet spectrophotometry and HPLC were used to determine the biliverdin concentration in eggshells, blood, bile, excreta, and shell gland of both groups of chickens. Biliverdin content was significantly different between egg shells of blue-shelled and brown-shelled chickens (P < 0.01). Blood and bile were tested 3 to 4 h before oviposition, and excreta was tested randomly. Results showed no significant difference in biliverdin concentration in blood, bile, and excreta between the 2 groups. In the shell gland, the biliverdin contents for the blue-shelled and brown-shelled chickens were 8.25 +/- 2.55 and 1.29 +/- 0.12 nmol/g, respectively, which showed a significant difference (P < 0.01). Our results demonstrated that blood is not the biosynthesis site of the shell biliverdin. Biliverdin is most likely synthesized in the shell gland and then deposited onto the eggshell of chickens.
胆绿素是鸡和其他鸟类蛋壳中的一种重要色素。确定胆绿素的生物合成位点对于理解蛋壳色素沉着的生化过程和遗传基础至关重要。血液或壳腺都可能是蛋壳胆绿素的生物合成位点。在中国本土鸡品种中构建了一个全同胞姐妹的分离群体，其基因型分别为Oo和oo，分别产下蓝壳蛋和浅褐壳蛋。采用紫外分光光度法和高效液相色谱法测定两组鸡的蛋壳、血液、胆汁、排泄物和壳腺中的胆绿素浓度。蓝壳蛋鸡和褐壳蛋鸡的蛋壳中胆绿素含量存在显著差异（P < 0.01）。在产卵前3至4小时采集血液和胆汁样本，排泄物样本随机采集。结果显示，两组鸡的血液、胆汁和排泄物中的胆绿素浓度无显著差异。在壳腺中，蓝壳蛋鸡和褐壳蛋鸡的胆绿素含量分别为8.25±2.55和1.29±0.12 nmol/g，差异显著（P < 0.01）。我们的结果表明，血液不是蛋壳胆绿素的生物合成位点。胆绿素很可能在壳腺中合成，然后沉积在鸡的蛋壳上。
