Schweigert F J, Stobo W T, Zucker H
Institute of Physiology, Physiological Chemistry and Nutrition Physiology, Veterinary Faculty, Ludwig-Maximilians-Universität München, West-Germany.
Int J Vitam Nutr Res. 1987;57(3):239-45.
Vitamin A and beta-carotene concentrations in serum, liver and blubber fat were investigated in 65 grey seals of different age and sex in the pupping colony on Sable Island, Canada to determine the vitamin A status. In none of the investigated samples could beta-carotene be detected. There were no differences in the concentration of vitamin A in serum, liver and blubber between male (213 micrograms/l, 376 micrograms/g, 22 micrograms/g respectively) and female (205 micrograms/l, 319 micrograms/g, 19 micrograms/g respectively) juveniles. In adult males concentrations of vitamin A in serum, liver and blubber were higher (260 micrograms/l, 503 micrograms/g, 34 micrograms/g respectively) than in juveniles indicating an age dependent increase of vitamin A in liver and blubber. Contrary to this in lactating females concentrations of vitamin A in serum, liver and blubber were significantly different than in the other animals. While the level of vitamin A in serum and blubber was two times higher with 413 micrograms/1 and 62 micrograms/g respectively, the concentration of vitamin A in liver was much lower (265 micrograms/g) compared to juveniles and adult males. It is possible that the intensified lipid metabolism during lactation, necessary to match the energy requirements of the rapidly growing pup, causes these extreme differences in vitamin A concentrations in serum, liver and blubber of lactating females compared to juveniles and adult males. Due to high concentration of vitamin A in blubber and the high proportion in blubber to total body weight, the blubber represents approximately 40% of total body reserves of vitamin A.
为确定维生素A状况，对加拿大黑貂岛育幼地65只不同年龄和性别的灰海豹的血清、肝脏和鲸脂中的维生素A及β-胡萝卜素浓度进行了研究。在所检测的样本中均未检测到β-胡萝卜素。雄性幼崽（血清、肝脏和鲸脂中维生素A浓度分别为213微克/升、376微克/克、22微克/克）和雌性幼崽（血清、肝脏和鲸脂中维生素A浓度分别为205微克/升、319微克/克、19微克/克）的血清、肝脏和鲸脂中维生素A浓度无差异。成年雄性海豹血清、肝脏和鲸脂中的维生素A浓度（分别为260微克/升、503微克/克、34微克/克）高于幼崽，表明肝脏和鲸脂中维生素A含量随年龄增长而增加。与此相反，哺乳期雌性海豹血清、肝脏和鲸脂中的维生素A浓度与其他动物显著不同。血清和鲸脂中维生素A水平分别高出两倍，为413微克/升和62微克/克，而肝脏中维生素A浓度（265微克/克）与幼崽和成年雄性相比则低得多。哺乳期为满足快速生长幼崽的能量需求而强化的脂质代谢，可能导致哺乳期雌性海豹血清、肝脏和鲸脂中维生素A浓度与幼崽和成年雄性相比出现这些极端差异。由于鲸脂中维生素A浓度高且鲸脂占总体重比例大，鲸脂约占维生素A全身储备的40%。
