Blakley B R, Bell R J
Department of Veterinary Physiological Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon.
Can Vet J. 1994 May;35(5):297-300.
The purpose of the study was to determine normal baseline levels of vitamin A and vitamin E in clinically normal horses under typical field conditions in Saskatchewan and Alberta. Heparinized blood samples were collected from approximately 400 clinically healthy horses selected from 24 locations in Alberta and Saskatchewan during a two-year period. For each horse, historical information including feed type, vitamin supplementation, time of year, sex, and age were recorded. From each blood sample, the plasma vitamin A (all-transretinol) and vitamin E (alpha-tocopherol) levels were measured using high pressure liquid chromatography. Normal baseline plasma vitamin A and vitamin E concentrations recorded during the study were 0.70 mumol/L and 7.65 mumol/L, respectively. The plasma vitamin concentrations were lower in the younger horses. The plasma vitamin levels were higher from May to August, as compared to other times of the year. Horses grazing fresh pasture exclusively during the summer months had plasma vitamin A and vitamin E concentrations that were 27% and 63% greater than horses fed harvested or stored feeds during the same time period. Sex-related differences were not evident in the study. A number of factors may influence the baseline plasma vitamin A and vitamin E levels in horses. Consequently, it is unadvisable to use a single evaluation to assess vitamin status. Multiple sampling from individual horses or sampling from many horses within a herd may reduce the variability and improve the ability to monitor vitamin status from plasma submissions.
本研究的目的是确定在萨斯喀彻温省和艾伯塔省典型野外条件下临床正常马匹的维生素A和维生素E的正常基线水平。在两年时间里，从艾伯塔省和萨斯喀彻温省24个地点挑选的约400匹临床健康马匹中采集了肝素化血样。对于每匹马，记录包括饲料类型、维生素补充情况、一年中的时间、性别和年龄等历史信息。从每份血样中，使用高压液相色谱法测量血浆维生素A（全反式视黄醇）和维生素E（α-生育酚）水平。研究期间记录的正常基线血浆维生素A和维生素E浓度分别为0.70μmol/L和7.65μmol/L。较年轻的马匹血浆维生素浓度较低。与一年中的其他时间相比，5月至8月血浆维生素水平较高。在夏季仅放牧新鲜牧场的马匹，其血浆维生素A和维生素E浓度比同期喂食收获或储存饲料的马匹分别高27%和63%。在本研究中，性别相关差异不明显。许多因素可能影响马匹血浆维生素A和维生素E的基线水平。因此，使用单一评估来评估维生素状态是不可取的。从个体马匹进行多次采样或从畜群中的许多马匹进行采样，可能会降低变异性并提高从血浆样本监测维生素状态的能力。
