Antioxidant Capacity Of Milk Research Articles

Enrichment of milk antioxidant activity by dietary supplementation of red clover isoflavone in cows and its improvement on mice intestinal health

Red clover (Trifolium pratense) isoflavone was supplemented to dairy cows, and antioxidant capacity of milk was assessed. Treated cows increased the activities of antioxidant enzymes, reduced production of oxidation products, and enhanced the concentrations of vitamin E and vitamin C. Moreover, milk fatty acid profile was positive influenced by 8 g/kg red clover isoflavone, with changes in the lower saturated and higher unsaturated fatty acids. We further demonstrated the efficacy of antioxidant capacity of milk in mice, found that milk from cows feeding red clover isoflavone increased the expressions of antioxidant enzymes, and alleviated lipopolysaccharide (LPS)-stimulated tissue damage of duodenum and jejunum, which was related to upregulated metabolism pathways of carbohydrate, lipid, and amino acid, as well as downregulated inflammatory related pathways. Together, dietary supplementation of red clover isoflavone is an effective way to improve milk antioxidant capacity, providing a natural strategy for developing functional foods.

Antioxidants Capacity of Milk, Probiotics and Postbiotics: A Review

This paper explores the antioxidant capacity of milk, probiotics, and postbiotics. Antioxidants are compounds that can protect cells from damage caused by free radicals, which are unstable molecules that can cause oxidative stress. Milk is a rich source of antioxidants, including vitamins A and E, and some evidence suggests that milk consumption may be associated with a reduced risk of chronic diseases. Probiotics are live microorganisms that can confer health benefits when ingested, and some strains have been shown to have antioxidant properties. Postbiotics are non-viable microorganisms or their metabolites, and recent research has suggested that they may have antioxidant effects. This paper reviews the current evidence on the antioxidant capacity of milk, probiotics, and postbiotics, and discusses the potential implications for human health. Overall, the findings suggest that these three sources may have antioxidant effects, which could contribute to their health-promoting properties. However, further research is needed to fully understand the mechanisms underlying these effects and to determine their clinical relevance.

Evaluating the total antioxidant capacity of processed milk: utilising applicable antioxidant assays and key antioxidant components

SummaryTotal antioxidant capacity (TAC) holds immense importance in evaluating the milk quality. However, achieving accuracy and comparability in TAC measurement requires a thorough examination of detection methods and the constituents of antioxidants. This research focussed on developing TAC evaluation system tailored for processed milk, and the applicability of four assays (ABTS, FRAP, DPPH and ORAC) was examined, considering their compatibility with antioxidants. For fractionated milk, defatting and deproteinisation processes targeted reduced fat‐soluble (phospholipids by 88.75%) and water‐soluble (ascorbic acid and riboflavin by 55.22% and 63.85%) components, respectively. ORAC assay proved effective for detecting deproteinised milk, whereas DPPD assay displayed heightened sensitivity to alterations in milk fat antioxidants. Regarding pressure‐ and heat‐treated milk, homogenisation increased the availability of phosphatidylcholine (36.59–57.53 mg/L) and sphingomyelin (5.56–10.35 mg/L). However, the TAC of heat‐treated milk experienced a significant reduction due to the degradation of various fat‐soluble antioxidants. ORAC and ABTS assays were found suitable for assessing homogenised and heat‐treated milk, respectively. The peroxide value of reconstituted processed milk fell within the range of 98.48%–104.57% compared to untreated whole milk, affirming the accuracy of key antioxidants and detection methods. This study provides valuable insights for the meticulous assessment and enhancement of antioxidant capacity in milk.

Comparison of Total Antioxidant Capacity of Milk of Crossbred Holstein Friesian and Vechur Cattle during Different Lactation

Background: Milk is a rich source of vitamins, minerals, fats and high quality proteins. Milk proteins such as casein, lactoferrin and amino acids in milk like tyrosine, cysteine, tryptophan, lysine, etc. have antioxidant properties. The objective of this study was to compare the antioxidant level of milk of crossbred Holstein Friesian (CBHF) and Vechur cattle during different stages of lactation. Methods: Total antioxidant capacity (TAC) was estimated by using ferric reducing antioxidant assay. Milk samples from six animals each of CBHF and Vechur cattle were collected separately at early lactation, mid lactation and late lactation period. Results: Milk samples from CBHF and Vechur cattle during the early stages of lactation had significantly higher total antioxidant capacity than milk samples from later stages of lactation. This could be because of the high fat content in the early phases. The total antioxidant content of Vechur milk was higher than that of CBHF milk throughout lactation. The milk of the Vechur cow contains higher beta casein A2 than A1. No significant difference in the TAC values noticed between milk of mid and late lactation in both CBHF and Vechur cattle. The high antioxidant capacity of milk from Vechur cattle suggests that it has a great therapeutic potential. Different animal milk and milk products with antioxidant defense systems can be considered to have health-beneficial effects against free radical damage.

Effects of Hemp Seed on the Production, Fatty Acid Profile, and Antioxidant Capacity of Milk from Goats Fed Hay or a Mixed Shrubs-Grass Rangeland.

The research objective was to evaluate the effect of dietary incorporation of hemp seeds in goats fed with hay or mixed shrubs-grass rangeland on the production, FA profile and health-related lipid indices, antioxidant content and total antioxidant capacity of milk, with the purpose to increase the content of beneficial ingredients in milk and to improve its functional activity. Forty indigenous Carpathian goats were allocated into two groups according to the type of basic forage in their diet: hay (H) or mixed shrubs-grass rangeland (SG); each of them was further divided into two subgroups according to the presence of Hs in the concentrate mixture (250 g/kg) or not. Milk production was determined, and milk samples were collected and analyzed for fat, protein, lactose, and cholesterol content, as well as FA profile, lipophilic antioxidant content (α-tocopherol and retinol), and milk TAC. SG goats gave less milk (p < 0.01) but with higher milk fat (p < 0.001) and lower cholesterol content (p < 0.01) than H goats, while milk protein and lactose contents were not affected. Supplementing the diet with Hs caused a significant increase in milk production (p < 0.05) and milk fat content (p < 0.001) and a decrease in cholesterol content (p < 0.05). Grazing compared to indoor feeding but also supplementing the diet with Hs had the effect of decreasing the proportion of SFAs and increasing the concentrations of polyunsaturated FA (PUFA) in goat milk fat (p < 0.01). Fats in the milk of SG goats compared to H, but also in those supplemented with Hs, showed significantly higher proportions of vaccenic acid (VA), rumenic acid (CLA c-9,t-11) and omega-3 FA (α-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosapentaenoic acid (DPA)) which are considered healthy for consumers. The feeding system based on SG and the diet supplementation with Hs ensured the best nutritional and functional quality of milk, confirmed by the FA profile, antioxidant content, and by the value of health-related lipid indices (n-6/n-3 FA ratio and hypo-/hypercholesterolemia, atherogenic index (AI), thrombogenic index (TI), and health promotion index (HPI)). The results of our work will be useful for the development of optimal nutritional strategies that improve the FA profile and the antioxidants content in goat milk, with beneficial effects on human health.

Effects of graded levels of dietary pomegranate peel on methane and nitrogen losses, and metabolic and health indicators in dairy cows

This study aimed to quantify the effects of dietary inclusion of tannin-rich pomegranate peel (PP) on intake, methane and nitrogen (N) losses, and metabolic and health indicators in dairy cows. Four multiparous, late-lactating Brown Swiss dairy cows (796 kg body weight; 29 kg/d of energy corrected milk yield) were randomly allocated to 3 treatments in a randomized cyclic change-over design with 3 periods, each comprising 14 d of adaptation, 7 d of milk, urine, and feces collection, and 2 d of methane measurements. Treatments were formulated using PP that replaced on a dry matter (DM) basis 0% (control), 5%, and 10% of the basal mixed ration (BMR) consisting of corn and grass silage, alfalfa, and concentrate. Gaseous exchange of the cows was determined in open-circuit respiration chambers. Blood samples were collected on d 15 of each period. Individual feed intake as well as feces and urine excretion were quantified, and representative samples were collected for analyses of nutrients and phenol composition. Milk was analyzed for concentrations of fat, protein, lactose, milk urea N, and fatty acids. Total phenols and antioxidant capacity in milk and plasma were determined. In serum, the concentrations of urea and bilirubin as well as the activities of alanine aminotransferase (ALT), aspartate aminotransferase, glutamate dehydrogenase, alkaline phosphatase, and γ-glutamyl transferase were measured. The data were subjected to ANOVA with the Mixed procedure of SAS, with treatment and period as fixed and animal as random effects. The PP and BMR contained 218 and 3.5 g of total extractable tannins per kg DM, respectively, and thereof 203 and 3.3 g of hydrolyzable tannins. Total DM intake, energy corrected milk, and methane emission (total, yield, and intensity) were not affected by PP supplementation. The proportions of C18:2n-6 and C18:3n-3 in milk increased linearly as the amount of PP was increased in the diet. Milk urea N, blood urea N, and urinary N excretion decreased linearly with the increase in dietary PP content. Total phenols and antioxidant capacity in milk and plasma were not affected by the inclusion of PP. The activity of ALT increased in a linear manner with the inclusion of PP. In conclusion, replacing up to 10% of BMR with PP improved milk fatty acid composition and alleviated metabolic and environmental N load. However, the elevated serum ALT activity indicates an onset of liver stress even at 5% PP, requiring the development of adaptation protocols for safe inclusion of PP in ruminant diets.

Effects of Supplementation with an Herbal Mixture on the Antioxidant Capacity of Milk.

The aim of this study was to assess the effect of the addition of a standardized herbal mixture to the feed ration for Holstein-Friesian cows on the antioxidant capacity of milk. The study was carried out on a farm specialized in breeding dairy cattle. The exact study involved 30 cows in lactation III, which were in the first phase of lactation at the beginning of the experiment (15 cows-control group; 15 cows-experimental group). The nutrition supplied to the cows was based on the TMR (total mixed ration) system, with roughage and concentrate fodder used as the basis of the feed ration. The addition of a standardized blend of dried herbs, i.e., oregano (Origanum vulgare), thyme (Thymus vulgaris), purple coneflower (Echinacea purpurea), and cinnamon bark (Cinnamomum zeylanicum), was the experimental factor. Powdered herbs were administered as a component of the concentrate fodder at the dose of 3% DM ration/day/head. Milk samples were collected four times during the experiment (term 0 after the colostrum period and then after lactation weeks 2, 4, and 6). The following parameters were determined in the milk: the basic chemical composition, i.e., the content of total protein, fat, lactose, and casein; somatic cell count; content of selected whey proteins (α-lactalbumin, β-lactoglobulin, lactoferrin, BSA); and fat-soluble vitamins (A, D3, E). Additionally, the milk antioxidant capacity (ABTS, FRAP, DPPH) was determined and the degree of antioxidant protection (DAP) was calculated. It was shown that the milk from cows receiving the herbal blend-supplemented fodder had a higher content of casein, compared to the control group. The herbal supplementation contributed to a significant increase in the content of bioactive compounds, i.e., selected whey proteins (β-lactoglobulin, lactoferrin) and lipophilic vitamins (A, E). The milk was also characterized by significantly higher antioxidant potential (regardless of the measurement method) and a higher degree of antioxidant protection (DAP).

The Effects of Feeding Milled Rapeseed Seeds with Different Forage:Concentrate Ratios in Jersey Dairy Cows on Milk Production, Milk Fatty Acid Composition, and Milk Antioxidant Capacity.

We aimed to evaluate the effects of milled rapeseed (MR) supplementation of low- or high-concentrate diets on milk production and composition, fatty acids (FAs) profile, and antioxidant capacity. Sixteen Jersey dairy cows were used in a 4 × 4 Latin square design, for four periods of 4 weeks, and assigned to four treatments as a 2 × 2 factorial design. Dietary treatments consisted of iso-nitrogenated total mixed rations with high (65:35; LC-low concentrate) or low (50:50; HC-high concentrate) forage:concentrate (FC) ratios, supplemented with MR to provide 30 g oil/kg dry matter (DM) (LR and HR), or without MR supplement (L and H). Increasing the proportion of concentrates led to an increase in DM intake (DMI), net energy (NEL) intake, and milk production, but milk fat and protein content decreased. Supplementing diets with MR led to an increase in NEL intake and milk production, but did not affect DMI and milk composition. Diets supplemented with MR caused a decrease in the concentration of FAs with atherogenic effect and the increase in the level of FAs beneficial for human health (C18:1 cis-9, C18:1 trans-11, and C18:3 n-3), while the decrease in the FC ratio had a negative effect on omega-3 FAs. An improvement in the antioxidant capacity of milk was observed with diets with the high FC ratio but also by supplementing the feed with MR. These results could contribute to the development of effective strategies to improve the nutritional quality of milk without affecting the productive performance of cows.

Breed and Feeding System Impact the Bioactive Anti-Inflammatory Properties of Bovine Milk.

In the present study, we aimed at assessing the influence of breed and feeding system on the bovine milk profile of betaines and carnitines and milk capacity in counteracting the inflammatory endothelial cell (EC) damage induced by interleukin (IL)-6. In the first experimental design, two breeds were chosen (Holstein vs. Modicana) to investigate the biomolecule content and antioxidant capacity in milk and dairy products. In the second experimental design, two feeding systems (pasture vs. total mixed ratio) were tested only in Holstein to evaluate the possible effect on the functional profile of milk and dairy products. Finally, the bulk milk from the two experimental designs was used to evaluate the efficacy of preventing IL-6-induced endothelial inflammatory damage. Results showed that Modicana milk and whey had higher biomolecule content and antioxidant activity compared to Holstein milk (p < 0.01). Milk from Holstein fed TMR showed higher concentration of γ-butyrobetaine, δ-valerobetaine (p < 0.01), and l-carnitine (p < 0.05). Similarly, whey from Holstein fed TMR also showed higher content of δ-valerobetaine, glycine betaine, l-carnitine, and acetyl-l-carnitine (p < 0.01) compared to the Holstein fed pasture. Conversely, the antioxidant activity of milk and dairy products was not affected by the feeding system. In ECs, all milk samples reduced the IL-6-induced cytokine release, as well as the accumulation of reactive oxygen species (ROS) and the induction of cell death, with the most robust effect elicited by Modicana milk (p < 0.01). Overall, Modicana milk showed a higher content of biomolecules and antioxidant activity compared to Holstein, suggesting that the breed, more than the feeding system, can positively affect the health-promoting profile of dairy cattle milk.

Feeding Calcium-Ammonium Nitrate to Lactating Dairy Goats: Milk Quality and Ruminal Fermentation Responses.

Simple SummaryCalcium-ammonium nitrate (CAN) has been extensively used as a potential methane inhibitor for ruminants; however, there is still a need for studies focused on investigating its effects on the fatty acid profile and antioxidant capacity of milk, especially from dairy goats. Therefore, we evaluated the effects of CAN on nutrient digestibility, ruminal fermentation, and milk quality of lactating Saanen goats. Treatments consisted of a control diet (without CAN), 10 g of CAN per kg of dry matter, and 20 g of CAN per kg of dry matter. Supplemental CAN did not affect feed intake, digestibility of nutrients, and most ruminal fermentation parameters. Yields and composition of milk were not affected, and minor treatment effects were observed on the milk fatty acid profile. Milk antioxidant capacity was altered by increased conjugated dienes and reduced thiobarbituric acid reactive substances, along with greater concentrations of nitrate and nitrite residues in milk. Calcium-ammonium nitrate can be fed to lactating dairy goats up to 20 g per kg of dry matter without negative effects on nutrient digestibility and milk composition; however, it increased the concentration of conjugated dienes in milk, which may induce its faster lipid oxidation.We aimed to investigate the effects of calcium-ammonium nitrate (CAN) fed to lactating dairy goats on dry matter (DM) intake, digestibility of nutrients, milk properties (composition, antioxidant capacity, fatty acid profile, and nitrate residues), and ruminal fermentation parameters. Twelve lactating Saanen goats averaging 98.5 ± 13.1 days in milk, 53.5 ± 3.3 kg of body weight, and 2.53 ± 0.34 kg of milk/day were randomly assigned in four 3 × 3 Latin squares to receive the following diets: a control group (without CAN) with 7.3 g/kg DM of urea (URE), 10 g/kg DM of CAN (CAN10), and 20 g/kg DM of CAN (CAN20). Each period lasted 21 days, with 14 days for diet adaptation and seven days for data and sample collection. The DM intake, digestibility of nutrients, yields of milk, 3.5% fat-corrected milk, and energy-corrected milk were not affected by treatments. Similarly, there were no treatment effects on the yields and concentrations of milk fat, true protein, and lactose, along with minor effects on milk fatty acid profile. Total antioxidant capacity in milk was unaffected by treatments; however, concentration of conjugated dienes increased, while thiobarbituric acid reactive substances in milk decreased linearly. Nitrate and nitrite residues in milk were elevated by treatments, while the total of volatile fatty acids and ammonia-N concentration in the rumen were unaffected. Collectively, feeding CAN (up to 20 g/kg of DM) to lactating dairy goats did not affect feed intake, nutrient digestibility, and milk composition; however, it may increase milk lipid oxidation, as evidenced by increased conjugated diene concentration.

The Effect of Sustainable Feeding Systems, Combining Total Mixed Rations and Pasture, on Milk Fatty Acid Composition and Antioxidant Capacity in Jersey Dairy Cows.

Simple SummaryUntil now, only a limited number of studies have addressed the influence of combining grazing with total mixed rations (TMRs), in Jersey cows, on milk biocomponents and antioxidant capacity. Thus, the main objective of this study was to compare fatty acid (FA) profiles and antioxidant capacity in milk yielded by cows fed either using a TMR or a partial mixed ration (pTMR) combining a TMR and grazing. The second objective consisted in evaluating FA profiles and changes in lipophilic antioxidants in milk during the grazing period and related to pasture chemical composition. Although the pTMR feeding system led to a decreased daily milk production, milk quality was improved. By comparison, cows having access to pasture (pTMR group) yielded a milk with a higher fat and protein content, but with lower saturated FAs (SFA) and a higher content of unsaturated FAs considered benefic for human health (vaccenic acid (VA), conjugated linoleic acid (CLA), and omega-3 FA (n-3 FA)). Similarly, lipophilic antioxidant (α-tocopherol, retinol, and β-carotene) content was higher in the pTMR group, resulting in a higher total antioxidant capacity in milk. The grazing period showed a significant influence on milk quality; in the milk from the pTMR group, the highest concentrations of benefic FAs (VA, CLA, and n-3 FA), the highest concentration of fat-soluble antioxidants, and the best antioxidant activity, respectively, were obtained in the first grazing period (May), in accordance with the pasture’s chemical composition.This study was carried out to assess the effect of using pasture combined with total mixed ration (TMR) on milk production and composition, fatty acid (FA) profiles, fat-soluble antioxidant content, and total milk antioxidant capacity (TAC). In addition, the effect of milk pasteurization and storage at 2 °C for 4 days, lipophilic antioxidants and TAC were assessed. Two homogeneous groups of Jersey cows (n = 8) were constituted, which were randomly assigned to one of the two treatments: TMR (without access to pasture), or partial mixed diet (pTMR: grazing 8 h/day + TMR indoors). To establish FA profiles and lipophilic antioxidants’ changes in milk during the grazing period, in case of the pTMR group the experimental period was spilt in three grazing periods: P1 (May), P2 (June), and P3 (June/July). Milk yielded from cows having limited access on pasture (pTMR diet) showed an improved FA profile, with higher concentrations of FAs considered benefic for human health (vaccenic acid (VA), conjugated linoleic acid (CLA), omega-3 FA (n-3 FA)) (p < 0.01) and a lower concentration of FAs with hypercholesterolemiant potential (C12:0, C14:0, and C16:0) (p < 0.05), compared to that of the TMR diet. This change in FA profile was correlated with improved sanogenous lipid indices of milk fat (n-6/n-3 FA atherogenic index and thrombogenic index). Milk yielded during the P1 grazing period had higher concentrations of VA, CLA, and n-3 FA (p < 0.05) and lower concentrations of C14:0 and C16:0 (p < 0.01); it exhibited the best values for the main sanogenous fat lipid indices of fat. Moreover, pTMR milk showed a higher α-tocopherol, retinol, and β-carotene content (p < 0.05), positively correlated with TAC values in milk (P1 ˃ P2 ˃ P3). By comparison, cows fed using the TMR diet yielded a higher quantity of milk (p < 0.05), but a lower fat and protein content (p < 0.01), and also a higher saturated FAs and n-6 FA content (p < 0.05) together with a lower concentration of lipophilic antioxidants in milk. Thermal treatment showed no effect on α-tocopherol and retinol content in milk, but their concentrations decreased during the storage, at the same time a TAC decrease. The results of this study prove the positive effect of using pasture combined with TMR on FA profiles, milk antioxidant content, and antioxidant capacity, with beneficial effects on nutrition and health in humans.

Fresh Phyllanthus emblica (Amla) Fruit Supplementation Enhances Milk Fatty Acid Profiles and the Antioxidant Capacities of Milk and Blood in Dairy Cows

The objective of this study was to investigate the effect of a diet supplemented with fresh amla fruit as a natural feed additive on blood metabolic parameters, milk antioxidant capacity, and milk fatty acid (FA) proportions in lactating dairy cows. Eight ruminally cannulated mid-lactation dairy cows were used in a repeated crossover design. The first group of four cows received total mixed ration (TMR) feed without fresh amla fruit (control group). The remaining four cows sequentially supplemented fresh amla fruit (FAF) at three levels (200, 400, then 600 g/d) (treatment group) at 14-day intervals. In second period, control and treatment groups were exchanged. The first ten days were adjusted to diet adaptation for each sub-period, and the last four days for sampling milk and blood. A total of 514 metabolites were detected from FAF using UPLC-ESI-MS/MS. The five main metabolites in FAF were phenolic acids (22%), flavonoids (20%), lipids (20%), amino acids and derivatives (9%), and tannins (7%). Amla fruit supplementation reduced total saturated fatty acid and the omega-6/omega-3 ratio at 200 or 400 g/d FAF dose compared to controls. In addition, amla fruit increased unsaturated FA, such as C20:5 (Eicosapentaenoic acid, EPA) and C22:6 (docosahexaenoic acid, DHA), and branched-chain FA in a dose-dependent manner at 200 or 400 g/d compared to controls. In addition, amla fruit increased the antioxidant capacity biomarkers in the blood, such as superoxide dismutase (SOD) and albumin; this confirms that amla fruit is an excellent antioxidant, inhibiting reactive oxygen species’ (ROS) metabolism, and can thereby protect cells from oxidative stress. Moreover, the most remarkable improvement of ferric reducing-antioxidant power (FRAP) and total antioxidant capacity (TAC) in milk was recorded at 400 g/d FAF doses compared to controls. Therefore, fresh amla fruit doses for lactating cows at 400 g/d on an as-fed basis can be used as an alternative additive feed in dairy cow diets to improve antioxidant capacity, protein efficiency, butter quality, and to produce more desirable milk fatty acid profiles for human consumption.

Antioxidant Activity of Milk and Dairy Products.

Simple SummaryConsumption of food products that are rich in natural antioxidants improves the antioxidant status of an organism through protection against oxidative stress and damage. Milk and dairy products (yogurt and cheese) accounting for approximately 25–30% of the average human diet are undoubtedly a rich source of compounds exhibiting antioxidant properties. The aim of the study was to present a review of literature data on the antioxidant potential of raw milk and dairy products (milk, fermented products, and cheese) and the possibility to modify its level at the milk production and processing stage. The antioxidant capacity of milk and dairy products is mainly related to the presence of sulfur amino acids, whey proteins (especially β-lactoglobulin), vitamins A, E, and C, or β-carotene. The processes of fermentation or cheese maturation are associated with the release of bioactive peptides, which are responsible for the level of the antioxidant status of the product. The use of probiotic strains significantly enhances the antioxidant status. The antioxidant status of milk and dairy products can be modified with the use of natural additives in animal nutrition or at the stage of milk processing. Herbal mixtures, seeds, fruits, and waste from the fruit and vegetable industry are used most commonly. It is worth emphasizing that regular consumption of natural dairy antioxidants minimizes the risk of development of civilization diseases (e.g., cardiovascular disease, cancer, or diabetes). It also slows down the aging process in the organism.The aim of the study was to present a review of literature data on the antioxidant potential of raw milk and dairy products (milk, fermented products, and cheese) and the possibility to modify its level at the milk production and processing stage. Based on the available reports, it can be concluded that the consumption of products that are a rich source of bioactive components improves the antioxidant status of the organism and reduces the risk of development of many civilization diseases. Milk and dairy products are undoubtedly rich sources of antioxidant compounds. Various methods, in particular, ABTS, FRAP, and DPPH assays, are used for the measurement of the overall antioxidant activity of milk and dairy products. Research indicates differences in the total antioxidant capacity of milk between animal species, which result from the differences in the chemical compositions of their milk. The content of antioxidant components in milk and the antioxidant potential can be modified through animal nutrition (e.g., supplementation of animal diets with various natural additives (herbal mixtures, waste from fruit and vegetable processing)). The antioxidant potential of dairy products is associated with the quality of the raw material as well as the bacterial cultures and natural plant additives used. Antioxidant peptides released during milk fermentation increase the antioxidant capacity of dairy products, and the use of probiotic strains contributes its enhancement. Investigations have shown that the antioxidant activity of dairy products can be enhanced by the addition of plant raw materials or their extracts in the production process. Natural plant additives should therefore be widely used in animal nutrition or as functional additives to dairy products.

Associations between osteopontin gene polymorphism (OPN), milk yield, somatic cell score and age of cattle on milk antioxidant capacity

Selection of cows based on the antioxidant capacity and chemical composition of their milk has a social dimension and can be considered a contribution towards the mitigation of diseases of affluence. This study addressed the hypothesis that greater antioxidant capacity of milk is not always associated with health-promoting properties. It was demonstrated that the milk's antioxidant capacity varied to a significant extent according to the cow's age, daily milk yield and somatic cell score, and that the total antioxidant capacity increased in proportion to the somatic cell score. This study is also the first to investigate the effects of polymorphism of the osteopontin gene on the antioxidant capacity of milk. The osteopontin genotype was associated, to a significant extent, with the percentage of protein in milk, and therefore this gene can be considered a marker of the technological usefulness of milk.

PSIX-9 Effect of calcium nitrate fed to dairy cows on nitrate residues, fatty acids profile, and antioxidant capacity in milk

Abstract Six lactating cows (106.3 ± 14.8 DIM; 550.7 ± 21.8 kg BW) were enrolled in a replicated 3 × 3 Latin square to evaluate the supplementation of double salt of calcium ammonium nitrate decahydrate (CAN), composed by 16.5% N, 76.5% of nitrate (NO3 -), and 85.0% DM, on NO3 - and nitrite (NO2 -) residues, fatty acids (FA) proportion, and antioxidant capacity in milk. Each period lasted 21 d, with 14 d for adaptation and 7 d for sampling. Treatments were URE (11.9 g/DM of urea as a control), CAN15: 15 g of CAN (11.5 g of NO3 - on DM), and CAN30: 30 g of CAN (23 g of NO3 - on DM). Milk samples were collected on d 15–16 of each period, frozen at –20°C, and after analyzed for NO3 - and NO2 - residues, fatty acids, and antioxidant capacity. Data were analyzed using PROC MIXED of SAS. Supplemental CAN increased by 26% NO3 - residue in milk (P = 0.02), whereas did not affect (P &amp;lt; 0.05) NO2 - concentration (average of 0.042 mg/L). Total CLA and short-chain FA were not affected (P &amp;gt; 0.05) by CAN. Medium-chain FA decreased linearly (P &amp;lt; 0.05), while long-chain FA (P = 0.06) and monounsaturated FA (P = 0.08) tended to increase linearly. Saturated FA reduced (P &amp;lt; 0.05) linearly; however, the total of polyunsaturated FA was not affected (P &amp;gt; 0.05). There were no effects of CAN (P &amp;gt; 0.05) on n-3, n-6, and n-6/n-3 ratio. Milk reducing power and TBARS concentration were not affected (P &amp;gt; 0.05) by CAN, whereas conjugated dienes increased (P = 0.02) linearly (URE= 47.6 vs. CAN15= 52.7 vs. CAN30= 63.4 mmol/kg of fat). Supplementing CAN at 30 g/DM reduced total saturated FA and increased conjugated dienes, caused possibly by lower rumen biohydrogenation, which might increase lipid oxidation in milk.

Effect of Yellow Wine Lees Supplementation on Milk Antioxidant Capacity and Hematological Parameters in Lactating Cows under Heat Stress.

Simple SummaryThe yellow wine lees (YWL), a byproduct of the yellow wine brewing industry which contain high levels of crude protein and anti-oxidative substrates can be a suitable ingredient in dairy rations. Total mixed rations (TMR) containing unfermented/fermented YWL were greater in total phenolic and flavonoid concentrations. Feeding lactating cows under heat stress with TMR containing unfermented or fermented YWL mix can reduce their inflammation response and oxidative stress, as well as improve fatty acid quality and oxidative stability of their milk.Fifteen multiparous lactating Chinese Holstein dairy cows were used in a replicated 3 × 3 Latin Square Design to evaluate the effect of total mixed rations (TMR) containing unfermented and fermented yellow wine lees (YWL) on the oxidative status of heat-stressed lactating cows and the oxidative stability of the milk and milk fatty acids they produced. Cows were fed with three isonitrogenous and isocaloric diets as follows: (1) TMR containing 18% soybean meal, (2) TMR containing 11% unfermented YWL (UM), and (3) TMR containing 11% fermented YWL (FM). The rectal temperature (at 1300 h) and respiratory rate were higher in control cows than in cows fed UM or FM. Both types of YWL were greater in total phenolic and flavonoid contents, reducing power, and radical scavenging abilities than soybean meal. Cows fed UM or FM had higher blood neutrophil, white blood cell, and lymphocyte counts, as well as lower plasma malondialdehyde level, higher plasma superoxide dismutase, glutathione peroxidase, and 2,2-diphenyl-1-picryl-hydrazyl-hydrate levels, and higher total antioxidant capacity in the plasma than those fed control diet. The proportion of milk unsaturated fatty acids was higher and that of saturated fatty acids was lower in UM- and FM-fed animals than in the control animals. Milk from UM- and FM-fed cows had lower malondialdehyde content but higher 2,2-diphenyl-1-picryl-hydrazyl-hydrate content than the control cows. In conclusion, feeding TMR containing UM and FM to cows reduced both the oxidative stress in heat-stressed cows and improved the oxidative capacity of their milk.

Annatto seeds as Antioxidants Source with Linseed Oil for Dairy Cows.

Simple SummaryCurrently, functional foods are gaining widespread attention. Polyunsaturated fatty acids (PUFA) and antioxidant compounds have beneficial effects on health. It is possible to increase the concentration of these compounds in the milk obtained from dairy cows by manipulating their diets, thereby improving milk quality and consequently the health of animals and humans who consume this milk. Annatto seed (Bixa orellana L.) is a source of antioxidants, whereas linseed oil is rich in omega 3 fatty acid. We evaluated the inclusion of annatto seeds and linseed oil in the diets of dairy cows and their effects on dry matter intake (DMI), nutrient digestibility, milk yield, milk composition and antioxidant capacity in milk and blood. There was no effect of treatment on nutrient digestibility and antioxidant capacity, but the addition of annatto seeds decreased DMI and milk production and linseed oil supplementation reduced milk fat content. This study aimed to evaluate the effects of annatto seeds, linseed oil and their combination on DMI, apparent total tract digestibility, antioxidant capacity and milk composition of dairy cows. Four lactating Holstein cows (120 ± 43 days in milk; 15.98 ± 2.02 kg of milk/day, mean ± SD) were allocated in a 4 × 4 Latin square with a 2 × 2 factorial arrangement (with or without annatto seeds at 15 g/kg of dry matter (DM); with or without linseed oil at 30 g/kg of DM) and provided four different diets: control (no annatto seeds or linseed oil); annatto seeds (15 g/kg of DM); linseed oil (30 g/kg of DM); and a combination of both annatto seeds and linseed oil. Annatto seeds reduced DM intake, and milk yield, protein and lactose, but increased content of fat, total solids and short chain fatty acid, with no effect on total antioxidant capacity of milk. Linseed oil supplementation decreased medium chain fatty acid proportion and n-6/n-3 ratio, conversely it increased long chain fatty acids and n-3 fatty acid content of milk, ether extract intake and total-tract digestibility. Thus, linseed oil supplementation in dairy cow diets improved the milk FA profile but decreased milk fat concentration, whereas annatto seeds did not influence antioxidant capacity and depressed feed intake and milk yield.

The Impact of Mastitis on the Biochemical Parameters, Oxidative and Nitrosative Stress Markers in Goat's Milk: A Review.

Goat mastitis has become one of the most frequently diagnosed conditions in goat farms, with significant economic impact on the dairy industry. Inflammation of the mammary gland poses serious consequences on milk composition, with changes regarding biochemical parameters and oxidative stress markers. The aim of this paper is to present the most recent knowledge on the main biochemical changes that occur in the mastitic milk, as well as the overall effect of the oxidative and nitrosative stress on milk components, focusing on both enzymatic and nonenzymatic antioxidant markers. Mastitis in goats is responsible for a decrease in milk production, change in protein content with pronounced casein hydrolysis, and reduction in lactose concentration and milk fat. Milk enzymatic activity also undergoes changes, regarding indigenous enzymes and those involved in milk synthesis. Furthermore, during mastitis, both the electrical conductivity and the milk somatic cell count are increased. Intramammary infections are associated with a reduced milk antioxidant capacity and changes in catalase, lactoperoxidase, glutathione peroxidase or superoxide dismutase activity, as well as reduced antioxidant vitamin content. Mastitis is also correlated with an increase in the concentration of nitric oxide, nitrite, nitrate and other oxidation compounds, leading to the occurrence of nitrosative stress.

Periparturient antioxidant enzymes, haematological profile and milk production of dairy cows supplemented with Moringa oleifera leaf meal

This study evaluated the effects of feeding transition Holstein cows with Moringa oleifera leaf meal (MOLM) on antioxidant enzymes, haematological profile and milk production. Forty-eight pregnant Holstein cows received increasing levels of Moringa oleifera leaf meal (MOLM) at M0: Control; M30: 8.33 g MOLM /100 kg BW and M60: 16.66 g MOLM /100 kg BW. Blood samples were collected to determine haematology, antioxidant enzymes and biochemistry. Milk was sampled to determine yield, composition, antioxidant status (MTAC) and somatic cell count (SCC). White blood cells (WBC) and red blood cells (RBC) were high in M60 group than those in M0 (P = 0.02) and (P = 0.03) respectively. Cows in M60 treatment group had higher (P < 0.01) serum superoxide dismutase (SOD) and total antioxidant capacity (STAC) than M30 and M0 treatment groups. Although, milk yield and body weight were not (P> 0.05) affected by treatment, cows in M60 group were recorded with the highest milk fat (P < 0.01), protein (P = 0.01) and MTAC (P < 0.01) values. In conclusion, supplementing MOLM (M60) to transition dairy cows was shown to improve blood biochemistry, antioxidant status and udder health. Moreover, milk composition and milk antioxidant capacity but not milk yield improved with supplementation of MOLM (M60).

Dietary pomegranate peel improves milk quality of lactating ewes: Emphasis on milk fat globule membrane properties and antioxidative traits

Concentrated pomegranate peel extract (CPE) was supplemented to ewes, and milk yield and fat content—fatty acid (FA) and phospholipid (PL) composition—were monitored. CPE-fed ewes had higher milk yield, and fat, protein and lactose contents than controls. Milk PL content—20% higher in the CPE-supplemented group—was regulated by treatment and not by total fat content; milk phosphatidylethanolamine and phosphatidylcholine increased by 22 and 26%, respectively, in CPE-supplemented vs. control ewes. Milk saturated FA concentration was higher, and total polyunsaturated and monounsaturated FA content lower in the CPE vs. control group, regardless of milk total fat content. CPE supplementation increased milk antioxidant capacity, suggesting antioxidant transfer from dietary source to milk, increasing stability and nutritive value. Our study provides first evidence for milk quality improvement in terms of antioxidants and PL enrichment without compromising total milk fat, suggesting strategies to improve dairy animals' milk composition without compromising total production.