Effects of vitamin E supplementation on and the association of body condition score with changes in peroxidative biomarkers and antioxidants around calving in dairy heifers

Transition cow clusters with distinctive antioxidant ability and their relation to performance and metabolic status in early lactation

Metabolic and oxidative stress have been characterized as risk factors during the transition period from pregnancy to lactation. Although mutual relations between both types of stress have been suggested, they rarely have been studied concomitantly. For this, a total of 99 individual transition dairy cows (117 cases, 18 cows sampled during 2 consecutive lactations) were included in this experiment. Blood samples were taken at -7, 3, 6, 9, and 21 d relative to calving and concentrations of metabolic parameters (glucose, β-hydroxybutyric acid (BHBA), nonesterified fatty acids, insulin, insulin-like growth factor 1, and fructosamine) were determined. In the blood samples of d 21, biochemical profiles related to liver function and parameters related to oxidative status were determined. First, cases were allocated to 2 different BHBA groups (ketotic vs. nonketotic, N:n = 20:33) consisting of animals with an average postpartum BHBA concentration and at least 2 out of 4 postpartum sampling points exceeding 1.2 mmol/L or remaining below 0.8 mmol/L, respectively. Second, oxidative parameters [proportion of oxidized glutathione to total glutathione in red blood cells (%)], activity of glutathione peroxidase, and of superoxide dismutase, concentrations of malondialdehyde and oxygen radical absorbance capacity were used to perform a fuzzy C-means clustering. From this, 2 groups were obtained [i.e., lower antioxidant ability (LAA80%, n = 31) and higher antioxidant ability (HAA80%, n = 19)], with 80% referring to the cutoff value for cluster membership. Increased concentrations of malondialdehyde, decreased superoxide dismutase activity, and impaired oxygen radical absorbance capacity were observed in the ketotic group compared with the nonketotic group, and inversely, the LAA80% group showed increased concentrations of BHBA. In addition, the concentration of aspartate transaminase was higher in the LAA80% group compared with the HAA80% group. Both the ketotic and LAA80% groups showed lower dry matter intake. However, a lower milk yield was observed in the LAA80% group but not in the ketotic group. Only 1 out of 19 (5.3%) and 3 out of 31 (9.7%) cases from the HAA80% and LAA80% clusters belong to the ketotic and nonketotic group, respectively. These findings suggested that dairy cows vary in oxidative status at the beginning of the lactation, and fuzzy C-means clustering allows to classify observations with distinctive oxidative status. Dairy cows with higher antioxidant capacity in early lactation rarely develop ketosis.

Erythrogram and oxidative stress in confined cattle fed with Brachiaria sp hay and supplemented with antioxidants

Abstract Brachiaria sp contains sporidesmin that can be oxidized by lipoperoxidation and cause oxidative stress. In the present study we evaluated the effects of different antioxidants on lipoperoxidation of erythrocytes from Nelore cattle fed with Brachiaria sp hay. The experimental design was entirely randomized, in which 40 whole male cattle were divided into five treatments (G1: control - no supplementation; G2: selenium and vitamin E supplementation; G3: zinc supplementation; G4: selenium supplementation and G5: vitamin E supplementation) and allocated in feedlot pens for 105 days. The samples heparinized and withethylenediaminetetraacetic acid (EDTA) were obtained every 28 days for hematological and oxidative stress evaluation (0, 28 56, 84 and 105 days). In the erythrogram total erythrocyte count, hemoglobin, and hematocrit (Ht) were measured. For the evaluation of oxidative stress, in order to analyze the characteristics of the erythrocyte membrane, the thiobarbituric acid reactive substances (TBARS), total glutathione (GSH-T), glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) were determined. The results showed that regardless of the treatment there was no oxidative stress during the experimental confinement period and that the joint association of selenium and vitamin E in the bovine diet provided a lower incidence of deleterious alterations on erythrocytes.

Eritrograma e estresse oxidativo em bovinos confinados alimentados com feno de Brachiaria sp. e suplementados com antioxidantes

Resumo As Brachiaria sp contêm esporidesminas que podem ser oxidadas por lipoperoxidação e ocasionar estresse oxidativo. No presente estudo foram avaliados os efeitos de diferentes antioxidantes na lipoperoxidação dos eritrócitos de bovinos da raça Nelore, alimentados com feno de Brachiaria sp. O delineamento experimental foi inteiramente casualizado, em que 40 bovinos machos, inteiros, foram divididos, em cinco tratamentos (G1: controle - sem suplementação; G2: suplementação de selênio e vitamina E; G3: suplementação de zinco; G4: suplementação de selênio e G5: suplementação de vitamina E) e alocados em baias de confinamento, por 105 dias. As amostras de plasma heparinizado ou com ácido etilenodiamino tetra-acético (EDTA) foram obtidas a cada 28 dias para avaliação hematológica e de estresse oxidativo (0, 28 56, 84 e 105 dias). No eritrograma foi mensurado a contagem total de eritrócitos, a hemoglobina e o volume globular (VG). Para a avaliação do estresse oxidativo, com o objetivo de analisar as características da membrana do eritrócito foram determinadas as substâncias reativas ao ácido tiobarbitúrico (TBARS), glutationa total (GSH-T), glutationa peroxidase (GSH-Px), catalase (CAT) e superóxido dismutase (SOD). Os resultados demonstraram que independente do tratamento não houve estresse oxidativo durante o período do confinamento experimental e que a associação conjunta de selênio e vitamina E na dieta dos bovinos proporcionaram menor incidência de alterações deletérias sobre os eritrócitos.

Direct effects of phenolic compounds on the mammary gland: In vivo and ex vivo evidence

We assessed the potential of Pistacia lentiscus (lentisk) phenolic compounds to enhance production of milk composition in lactating goats and caprine primary mammary epithelial cells (MEC). Damascus goats were given a lentisk infusion (LI) or fresh water (FW) to drink, in a crossover design. Milk from LI vs. FW goats was 0.43% richer in fat and 30% in omega 3 fatty acids. Lentisk infusion enhanced antioxidant capacity of plasma and milk by 37% and 30% respectively, and induced transcriptional activation of antioxidant genes. To assess the direct effect of polyphenols on milk quality in terms of composition and antioxidant capacity, we used plasma collected from goats fed hay (HP) or browsed on phenolic compounds-rich pasture (primarily lentisk; PP) as a conditioning medium for primary culture of MEC. PP increased 2-fold cellular triglyceride content and 2.4-fold intracellular casein, and increased ATP production and non-mitochondrial oxygen consumption. Taken together, the results imply that lentisk phenolic compounds affect blood, MEC and milk oxidative status, which increase fat production by the mammary gland.

Mitochondrial Bioenergetics of Extramammary Tissues in Lactating Dairy Cattle

Simple Summary

The nutrient and energy requirements of lactation are among the greatest required by any physiological process in the female mammal. The mammary gland and extramammary tissues undergo metabolic adaptations that coordinate changes in energy availability and nutrient partitioning that enable milk synthesis. Mitochondria are largely responsible for energy production in cells and their importance in milk synthesis has long been appreciated. However, mitochondrial adaptations across lactation are understudied, particularly for extramammary tissues with supporting roles in milk synthesis. Tracking mitochondrial function in dairy cattle across lactation, we found that the efficiency of energy production in the liver was elevated in the presence of fat-based substrates as the milk yield was increasing. In skeletal muscle, mitochondrial function showed little change across lactation and was not associated with milk production, suggesting that energy efficiency in this tissue is consistent regardless of the metabolic demands of lactation. A better understanding of mitochondrial bioenergetics during lactation may provide insight into the etiology of metabolic diseases during the transition period and low milk supply.

Abstract

Lactation is physiologically demanding, requiring increased nutrient and energy use. Mammary and extramammary tissues undergo metabolic changes for lactation. Although it has long been recognized that mitochondria play a critical role in lactation, the mitochondrial adaptations for milk synthesis in supporting tissues, such as liver and skeletal muscle are relatively understudied. In this study, we assessed the mitochondrial function in these tissues across lactation in dairy cattle. Tissue biopsies were taken at 8 ± 2 d (early, n = 11), 75 ± 4 d (peak, n = 11) and 199 ± 6 d (late, n = 11) in milk. Early lactation biopsies were harvested from one group of cows and the peak and late biopsies from a second cohort. Milk yield (MY) was recorded at each milking and milk samples were collected for composition analysis. Mitochondrial efficiency was quantified as the respiratory control ratio (RCR), comparing maximal to resting respiration rates. Liver complex II RCR was positively associated with MY. Liver ROS emission increased across lactation whereas liver antioxidant activity was similar across lactation. No change was detected in skeletal muscle RCR or ROS emission, but muscle GPx activity decreased across lactation and muscle SOD was negatively associated with MY. Muscle oxidative damage was elevated at early and late lactation. Across lactation, genes involved in mitochondrial biogenesis were upregulated in the liver. Our results indicate that during lactation, liver mitochondrial biogenesis and efficiency are increased, which is associated with greater milk yield. In contrast, the mitochondrial efficiency in skeletal muscle remains consistent across lactation, but undergoes oxidative damage, which is associated with reduced antioxidant activity.

Circulating oxidative stress status in Bedouin she-camels (Camelus dromedarius) during the peripartum period

This study aimed to assess the oxidative stress status in blood plasma of nomadic she-camels (Camelus dromedarius) during transition from late pregnancy to early lactation. From 12 late pregnant she-camels, blood was sampled weekly as they progressed from the third week prepartum up to the third week postpartum. Levels of albumin, uric acid, and malondialdehyde (a biomarker of lipid peroxidation) concentrations were fairly constant (P > 0.05) throughout the sampling times. Compared to the initial time (third week prepartum), values of the superoxide anion, total peroxides, and protein carbonyl (a biomarker of protein peroxidation) increased (P < 0.05) by more than 67%, 43%, and 23%, respectively, at parturition and this increase extended to the first week postpartum. Ascorbic acid concentration lost more than 20% (P < 0.05) of its value at parturition. Bilirubin value increased as camels progressed from the first week pre- up to the first week postpartum, and reached its maximum value (~ 2.5 fold) at parturition. Superoxide dismutase activity increased (P < 0.05) by 71.7% at the first week pretpartum and by 57% at parturition. Total antioxidant capacity level increased (P < 0.05) by ~ 25% at the first week prepartum and remained at this high level up to the second week postpartum. It seems that periparturient camels experience a substantial oxidative stress particularly at parturition and the week after calving as indicated by the increased peroxidative by-products of proteins in parallel to the enhanced production of pro-oxidants.

Monitoring the redox status in dairy cows by using plasma dROMs, PAT, and OSI biomarkers

The aim of this work was to determine the changes of redox indicators such as reactive oxygen metabolites (dROMs), plasma antioxidant test (PAT) and the oxidative stress index (OSI) in dairy cows at different stages of lactation using a diagnostic equipment which is suitable for in vivo oxidative stress (OS) monitoring procedures. In total, 628 dairy cows were examined in the pre-parturient period (days in milk [DIM]: -21 to -1 day; n = 117), in the calving and maternity period (DIM: 0 to 7; n = 137), in the early lactation period (DIM: 8 to 30; n = 139), and the in the peak lactation (DIM: 31 to 150; n = 235). The dROMs and OSI values were significantly different (P < 0.05) when comparing the 1st and 2nd+ lactation cows in each group. The highest mean value of dROMs was detected at the calving and maternity stage in 1st lactation cows (141 ± 25 U. Carr) and the lowest (103 ± 29 U. Carr) was found in peak lactation. The OSI developed similarly, with the highest value of 5.58 ± 0.94 in the calving and maternity period in the 1st lactation cows and the lowest value of 4.05 ± 1.21 in peak lactation and significant differences were found in many cases. Based on the results, the measurement of dROMs and OSI may be suitable for detecting oxidative stress in different lactation stages.

Graduate Student Literature Review: Mitochondrial adaptations across lactation and their molecular regulation in dairy cattle

As milk production in dairy cattle continues to increase, so do the energetic and nutrient demands on the dairy cow. Difficulties making the necessary metabolic adjustments for lactation can impair lactation performance and increase the risk of metabolic disorders. The physiological adaptations to lactation involve the mammary gland and extramammary tissues that coordinately enhance the availability of precursors for milk synthesis. Changes in whole-body metabolism and nutrient partitioning are accomplished, in part, through the bioenergetic and biosynthetic capacity of the mitochondria, providing energy and diverting important substrates, such as AA and fatty acids, to the mammary gland in support of lactation. With increased oxidative capacity and ATP production, reactive oxygen species production in mitochondria may be altered. Imbalances between oxidant production and antioxidant activity can lead to oxidative damage to cellular structures and contribute to disease. Thus, mitochondria are tasked with meeting the energy needs of the cell and minimizing oxidative stress. Mitochondrial function is regulated in concert with cellular metabolism by the nucleus. With only a small number of genes present within the mitochondrial genome, many genes regulating mitochondrial function are housed in nuclear DNA. This review describes the involvement of mitochondria in coordinating tissue-specific metabolic adaptations across lactation in dairy cattle and the current state of knowledge regarding mitochondrial-nuclear signaling pathways that regulate mitochondrial proliferation and function in response to shifting cellular energy need.

Capacity of Trolox to improve the development and quality of metabolically compromised bovine oocytes and embryos invitro during different windows of development

Trials to improve oocyte developmental competence under metabolic stress by using antioxidants may start before or after oocyte maturation. In the present conceptual study, we aimed to identify the most efficient timing of antioxidant application in relation to a metabolic insult using a bovine invitro embryo production model. Pathophysiological concentrations of palmitic acid (PA) were used to induce metabolic stress during oocyte maturation or embryo development. Trolox (TR; antioxidant) treatment prior to, during or after the PA insult was tested to evaluate the protective, neutralising and rescuing capacity of TR respectively. Changes in embryo developmental competence, mitochondrial activity, reactive oxygen species (ROS) concentrations, blastocyst cell allocation and apoptosis and cell stress-related gene expression were monitored. The improvement in developmental capacity was most obvious when oocytes were preloaded with TR before the PA insult. This protective effect could be explained by the observed combination of increased mitochondrial activity with reduced ROS production. This resulted in blastocysts with normal cell counts and apoptosis, as well as increased nuclear factor erythroid 2-related factor 2 (NRF2) expression (a marker for redox regulatory processes) and normalised the expression of the mitochondrial transcription factor A (TFAM), a marker of mitochondrial biogenesis. These results indicate that 'pretreatment' of oocytes with antioxidants produces embryos that seem to be more resilient to a metabolic stress insult.

Ethological and biological features of the organism of the black-and-white bulls when using natural feed additives in the diets

The authors studied the natural feed additive effect to the behaviour and biochemical blood composition of the black-and-white bulls. As results of the scientific experiment we came to the conclusion that using of the biologically active substance dihydroquercetin as a part of a natural feed additive in livestock feed for the metabolic processes intensity stimulation, the nutrient synthesis intensity and higher rates meat productivity formation.

Effects of close-up body condition score and selenium-vitamin E injection on lactation performance, blood metabolites, and oxidative status in high-producing dairy cows

High-producing dairy cows with high pre-calving body condition score (BCS) are more susceptible to metabolic disorders and oxidative stress. The aim of present study was to evaluate the effects of close-up BCS and 3 times Se-vitamin E (SeE) injection on BCS change, blood metabolites, oxidative status, and milk yield in high-producing Holstein cows. A total of 136 multiparous cows were divided into 2 groups based on their BCS including high (HB = 4.00 ± 0.20) and moderate (MB = 3.25 ± 0.25) at 3 wk before expected calving time. Then, each group was divided into 2 subgroups: 3 rounds of SeE injection at 21 d before, and 0 and 21 d after calving (+SeE), and no SeE injection (-SeE). Four final experimental groups were HB+SeE, MB+SeE, HB-SeE, and MB-SeE (34 cows each). Results indicated that interaction effect of BCS and SeE affected serum glucose, and the MB+SeE group had the highest level. The HB cows lost more BCS compared with MB cows during the postcalving period. Moreover, serum insulin concentration increased after SeE injection. The HB cows had higher serum nonesterified fatty acids at 14 d after calving. The MB cows tended to have higher activity of blood glutathione peroxidase over the study period. Furthermore, the SeE-injected cows tended to have higher activity of blood glutathione peroxidase at 28 d after calving. Serum albumin level was increased by SeE injection. The HB cows had greater milk production than MB cows, and SeE-injected cows tended to have higher milk fat percentage and higher fat:protein ratio compared with nonsupplemented cows. It was concluded that SeE injection had beneficial effects on some blood metabolites, albumin as a blood antioxidative parameter, and lactation performance in high-producing dairy cows, especially cows with moderate close-up BCS.

A 100-Year Review: Metabolic modifiers in dairy cattle nutrition

The first issue of the Journal of Dairy Science in 1917 opened with the text of the speech by Raymond A. Pearson, president of the Iowa State College of Agriculture, at the dedication of the new dairy building at the University of Nebraska (J. Dairy Sci. 1:4-18, 1917). Fittingly, this was the birth of a new research facility and more importantly, the beginning of a new journal devoted to the sciences of milk production and manufacture of products from milk. Metabolic modifiers of dairy cow metabolism enhance, change, or interfere with normal metabolic processes in the ruminant digestive tract or alter postabsorption partitioning of nutrients among body tissues. Papers on metabolic modifiers became more frequent in the journal around 1950. Dairy farming changed radically between 1955 and 1965. Changes in housing and feeding moved more cows outside, and cows and heifers in all stages of lactation, including the dry period, were fed as a single group. Rations became wetter with the shift to corn silage as the major forage in many rations. Liberal grain feeding met the requirements of high-producing cows and increased production per cow but introduced new challenges; for example, managing and feeding cows as a group. These changes led to the introduction of new strategies that identified and expanded the use of metabolic modifiers. Research was directed at characterizing the new problems for the dairy cow created by group feeding. Metabolic modifiers went beyond feeding the cow and included environmental and housing factors and additives to reduce the incidence and severity of many new conditions and pathologies. New collaborations began among dairy cattle specialties that broadened our understanding of the workings of the cow. The Journal of Dairy Science then and now plays an enormously important role in dissemination of the findings of dairy scientists worldwide that address existing and new technologies.

Protection of Bovine Mammary Epithelial Cells from Hydrogen Peroxide-Induced Oxidative Cell Damage by Resveratrol

The mammary epithelial cells (MECs) of high-producing dairy cows are likely to be subject to oxidative stress (OS) due to the intensive cell metabolism. The objectives of this study were to investigate the cytoprotective effects of resveratrol against hydrogen peroxide- (H2O2-) induced OS in cultured bovine MECs (MAC-T). Pretreatment of MAC-T cells with resveratrol could rescue the decrease in cell viability and resulted in lower intracellular reactive oxygen species (ROS) accumulation after H2O2 exposure. Resveratrol helped MAC-T cells to prevent H2O2-induced endoplasmic reticulum stress and mitochondria-related cell apoptosis. Moreover, resveratrol induced mRNA expression of multiple antioxidant defense genes in MAC-T cells under normal/oxidative conditions. Nuclear factor erythroid 2-related factor 2 (Nrf2) was required for the cytoprotective effects on MAC-T cells by resveratrol, as knockdown of Nrf2 significantly abolished resveratrol-induced cytoprotective effects against OS. In addition, by using selective inhibitors, we further confirmed that the induction of Nrf2 by resveratrol was mediated through the prolonged activation of PI3K/Akt and ERK/MAPK pathways but negatively regulated by p38/MAPK pathway. Overall, resveratrol has beneficial effects on bovine MECs redox balance and may be potentially used as a therapeutic medicine against oxidative insult in lactating animals.

Effect of Treadmill Exercise and Hydrogen-rich Water Intake on Serum Oxidative and Anti-oxidative Metabolites in Serum of Thoroughbred Horses

The present study aimed to clarify changes of oxidative stress and antioxidative functions in treadmill-exercised Thoroughbred horses (n=5, 3 to 7 years old), using recently developed techniques for measurement of serum d-ROMs for oxidative stress, and BAP for antioxidative markers. Also, the effect of nasogastric administration of hydrogen-rich water (HW) or placebo water preceding the treadmill exercise on these parameters was examined. Each horse was subjected to a maximum level of treadmill exercise in which the horses were exhausted at an average speed of 13.2 ± 0.84 m/sec. Blood samples were taken 4 times, immediately before the intake of HW or placebo water at 30 min preceding the treadmill exercise, immediately before the exercise (pre-exercise), immediately after the exercise (post-exercise) and at 30 min following the exercise. In all horses, both d-ROMs and BAP values significantly increased at post-exercise. The increase in d-ROMs tended to be lower in the HW trial, as compared to the placebo trial at pre-exercise. The increase in BAP was considerable at approximately 150% of the pre-exercise values in both the HW and placebo treatment trials. The BAP/d-ROMs ratio was significantly elevated at post-exercise in both treatment trials, while a significant elevation was also observed at pre-exercise in the HW trial. BAP, d-ROM, and the BAP/d-ROM ratio tended to decline at 30 min after the exercise, except BAP and BAP/d-ROMs in the placebo trial. These results demonstrate that the marked elevation of oxidative stress and anitioxidative functions occurred simultaneously in the intensively exercised horses, and suggest a possibility that HW has some antioxidative efficacy.

Oxidative stress index (OSi) as a new tool to assess redox status in dairy cattle during the transition period

Oxidative stress (OS) plays a key role in the initiation or progression of numerous diseases, and dairy cows undergo OS at the transition period. However, discrepancies between methodologies make it difficult to make comparisons between studies, and therefore research on this topic may not be implemented in farms. This study aims to test under field conditions the use of an oxidative stress index (OSi) as a combined measurement through a ratio between pro-oxidants and antioxidants throughout the transition period in dairy farms. Serum samples of high-yielding dairy cows were taken, and markers of oxidative damage and antioxidant capacity were measured in four different production stages: (i) late lactation (LL; -2 to -1 months); (ii) prepartum (PrP; -1 month until parturition); (iii) postpartum (PsP; delivery to +1 month); and (iv) peak of lactation (PkL; +1 to +2.5 months). Values were compared between production stages and against a metabolic baseline status (CTR, 4th to 5th month of gestation). To the best of our knowledge, this is the first report in the literature that discusses the values of these oxidative stress biomarkers (and the OS index) for cows with low metabolic demands, as to date most research in this area has focused on the transition period. With the joint evaluation through the OSi, differences were found that were not present with the separate evaluation of pro-oxidants or antioxidants, thus supporting our hypothesis that the OSi indicates more accurately the oxidative status of the animals. It was also confirmed that dairy cows undergo OS after parturition, and that antioxidant supplementation from 1 month before parturition until the peak of lactation may be needed to reduce the risk of OS.