Surynek J, Kucera A, Brandejs P
Vet Med (Praha). 1976 Sep;21(9):557-63.
The level of beta-carotene and vitamin A was studied in the blood plasma of the calves of the Bohemian Spotted breed (heifers, n = 24) and in the blood plasma of their mothers (n = 24). The experimental animals were divided according to the date of birth or parturition into two groups: from the 0th to the 7th day and from the 8th to the 14th day after birth or parturition. All the animals showed no manifest signs of disease, the over-all health condition of the herd was good. Examinations were performed in the period from September to October. The composition of calf feed ration guaranteed the supply of beta-carotene to the organism. The average vitamin A level in the cows 0 to 7 days after parturition was 66.0 mug per 100 ml and the average level of beta-carotene in the same animals was 950.9 mug per 100 ml of plasma. In calves 0 to 7 days after birth the average level of vitamin A reached 16.7 mug per 100 ml and that of beta-carotene 87.5 mug per 100 ml of plasma. The mentioned average values are higher than levels considered as deficient. The levels of both substances increased in calves with the time of sucking: hence an average vitamin A level of 29.8 mug per 100 ml of plasma and beta-carotene level of 280.1 mug per 100 ml of plasma were found in the calf category from the 8th to the 14th day after birth. In this age category the level of vitamin A in blood plasma was still highly significantly lower than in the blood plasma of their mothers; however, in beta-carotene the difference was not statistically significant. While the levels of vitamin A and beta-carotene in calf plasma increased with the time of sucking, the level of both substances in the plasma of their mothers decreased. However, the drop of the level of vitamin A in cow plasma 8--14 days after parturition is not statistically significant; on the other hand, the drop of beta-carotene was found significant. This suggests that the reserve of these substances, especially of beta-carotene, in the cows decreases in the post-partal period which would justify, in breeding practice, an increased supply of vitamin A and beta-carotene, both with respect to calf nutrition and with respect to the biological value of milk used for human consumption.
对波希米亚斑点品种犊牛（小母牛，n = 24）及其母亲（n = 24）的血浆中的β-胡萝卜素和维生素A水平进行了研究。实验动物根据出生或分娩日期分为两组：出生或分娩后第0至7天以及第8至14天。所有动物均无明显疾病迹象，牛群的整体健康状况良好。检查在9月至10月期间进行。犊牛饲料配方的组成保证了机体对β-胡萝卜素的供应。分娩后0至7天的母牛血浆中维生素A的平均水平为每100毫升66.0微克，同一动物中β-胡萝卜素的平均水平为每100毫升血浆950.9微克。出生后0至7天的犊牛血浆中维生素A的平均水平达到每100毫升16.7微克，β-胡萝卜素为每100毫升血浆87.5微克。上述平均值高于被认为缺乏的水平。随着吸吮时间的推移，犊牛体内这两种物质的水平均升高：因此，在出生后第8至14天的犊牛类别中，血浆中维生素A的平均水平为每100毫升29.8微克，β-胡萝卜素水平为每100毫升血浆280.1微克。在这个年龄组中，血浆中维生素A的水平仍显著低于其母亲的血浆；然而，β-胡萝卜素的差异无统计学意义。虽然犊牛血浆中维生素A和β-胡萝卜素的水平随着吸吮时间的推移而增加，但其母亲血浆中这两种物质的水平却下降。然而，分娩后8 - 14天母牛血浆中维生素A水平的下降无统计学意义；另一方面，β-胡萝卜素的下降是显著 的。这表明母牛体内这些物质，尤其是β-胡萝卜素的储备在产后阶段减少，这在育种实践中说明，就犊牛营养以及用于人类消费的牛奶的生物学价值而言，应增加维生素A和β-胡萝卜素的供应。
