Oxidative status along different stages of pregnancy in dairy cows
Oxidative status in the pregnant dairy cow
Introduction: The oxidant-antioxidant balance play a crucial role in the development of a stable pregnancy in dairy cows. The oxidant system is represented by the reactive oxygen species (ROS), which are indispensable molecules in different processes, like embryo implantation, uterine and cervical modification during the last phase of gestation. On the other hand, it’s fundamental to counterbalance oxidative stress, mostly in periods in which their levels can reach particularly high concentrations such as during early and late pregnancy. This task is prerogative of the antioxidant system, a complex of vitamins, enzymes and oligoelements, capable of transforming oxygen radicals into non-radical compounds. Between them, β-carotene stands out mainly for its antioxidant skills, but also for the important role played during pregnancy.
Aim: This study aims to evaluate serum β-carotene and Reactive Oxygen Species concentrations along different stages of pregnancy (from 30-60 days to 240-270 days), in Friesian dairy cows.
Materials and methods: 80 healthy, pregnant Friesian cows were enrolled in this study and, based on gestational age, the cows were divided into 8 groups of 10 animals each. Blood was sampled and the obtained serum was used to dose β-carotene and ROS, by means of photometric analytical systems.
Results and discussion: Results show that blood β-carotene concentrations undergo a progressive, slow reduction from 30-60 days of pregnancy, until 180-210 days, when they significantly decreased, whereas ROS levels increase, especially at 180-210 days. Both the reduction of β-carotene and the rise of ROS can be dangerous during pregnancy. Indeed, the potential risk of oxidative stress in the periparturient cow and in its embryo has been described.
Conclusion: Therefore, the results of this study support the growing evidence that an adequate β-carotene integration in the diet of the parturient cow should be recommended in order to curb oxidative stress both in the mother and the fetus.