Changes in biomarkers of nutrient metabolism, inflammation, and oxidative stress in dairy cows during the transition into the early dry period

Abstract

Metabolic stress occurs in dairy cows when physiologic homeostasis is disrupted as a consequence of aberrant nutrient metabolism, chronic inflammation, and oxidative stress. Early-lactation cows that suffer from metabolic stress are susceptible to health disorders that cause significant production losses. However, there is little information regarding the occurrence and effect of metabolic stress during involution. Therefore, the purpose of this study was to investigate well-known biomarkers associated with metabolic stress in early-lactation cows at various time points during the early dry period when dairy cows also are subjected to dramatic changes in physiologic homeostasis. Our group conducted a descriptive study by collecting serum and whole-blood samples from the coccygeal vein of 29 healthy dairy cows at a commercial dairy herd. Sampling points included d -6, 0, +1, +2, +6, and +12 relative to dry-off date. Samples were used to quantify biomarkers related to nutrient metabolism, oxidative stress, and inflammation that included calcium, nonesterified fatty acids, β-hydroxybutyrate, albumin, haptoglobin, cortisol, reactive oxygen and nitrogen species, antioxidant potential, oxidant status index, and isoprostanes. Additionally, whole-blood leukocyte differentials for total leukocyte, neutrophils, lymphocytes, eosinophils, and monocytes were analyzed. Within altered nutrient metabolism biomarkers, calcium and nonesterified fatty acid concentrations changed most from d 0 to d +2 during the sampling period. Indicators of oxidant status, such as reactive oxygen and nitrogen species, antioxidant potential, and oxidant status index, generally increased throughout the sampling period except at d +2, suggesting altered redox status throughout early involution. In contrast, isoprostane concentrations fluctuated throughout the study, demonstrating that indicators of oxidative damage occurred more sporadically during the sampling period. Therefore, many of the biomarkers associated with early-lactation metabolic stress also changed during the transition from late lactation to the early dry period, but not to the same magnitude and duration previously reported in periparturient cows. Future studies should be directed toward assessing whether the magnitude and duration of biomarker expression can affect the health and well-being of cows during the early dry period.

Oxylipid profiles of dairy cattle vary throughout the transition into early mammary gland involution

“…The effects of 11-HETE have been reported as potently pro-inflammatory, vaso-constrictive, and immunosuppressive (Ferreiro-Vera et al, 2011). In the present study, 11-HETE was increased at d +1, which is a sampling point where our previous study found that ROS production was also increased (Putman et al, 2018), and therefore may be a result of increased nonenzymatic production at this time.…”

“…In fact, it would be reasonable to think that the oxylipid profile of high-producing cows may differ from that of low-producing cows. However, our group found no differences in concentrations of other serum inflammatory biomarkers, such as acute phase proteins, between high-and low-producing cows during the early dry period (Putman et al, 2018). Therefore, we suggest that milk production may not affect oxylipid concentrations in the early dry period as they are also related to inflammation.…”

“…This pattern may be explained by the inflammation that occurs during early involution to adjust the mammary gland from a lactating to a nonlactating state because oxylipid production follows the onset of inflammation (Sordillo, 2018). This is supported by the fact that other biomarkers of inflammation in serum, such as nonesterified FA, albumin, and haptoglobin, suggested that dairy cattle undergo inflammation in the early dry period at d +1 and +12 in a previous study completed by our group (Putman et al, 2018). Additional support that the inflammation required by mammary involution may be related to oxylipid concentrations is provided because neutrophils and macrophages are abundant in the mammary gland during acute involution (Sordillo and Nickerson, 1988).…”

Colostrum supplementation with n-3 fatty acids and α-tocopherol alters plasma polyunsaturated fatty acid profile and decreases an indicator of oxidative stress in newborn calves

“…This decolorization assay is further described in Re et al (1999). Both assays used to assess oxidant status are detailed further by Putman et al (2018).…”

Prospects for predictive modeling of transition cow diseases

“…At this time, cows receive vaccinations and dry cow treatment regimens that are associated with later risk of diseases (Green et al, 2007). In addition, Putman et al (2018) found that many metabolic biomarkers associated with metabolic stress in early lactation fluctuated in the immediate days following dry-off. Nutritional management of dry cows is also critical to aid calcium metabolism and to control the release of NEFA from adipose tissue (Overton and Waldron, 2004).…”