Article

Grazing increases the unsaturated fatty acid concentration of milk from grass-fed cows: A review of the contributing factors, challenges and future perspectives

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Abstract

Grazing animals walk outdoors and harvest fresh herbage from a three-dimensional canopy. Botanical composition and grassland management in various farming systems affect herbage intake and milk fatty acid (FA) composition. Grazing animals encounter a vertical gradient while grazing down a sward; responses in milk FA composition are discussed. Grazing animals have diets rich in poly-unsaturated fatty acids (PUFA), particularly α-linolenic acid (C18:3n-3). Concentrates and starch-rich fodders affect rumen retention time of the feed, increase linoleic acid (C18:2n-6) intake, and alter biohydrogenation pathways toward less n-3 PUFA and less rumenic acid (conjugated linoleic acid (CLA) isomer C18:2c9t11), leading to lower contents of these compounds in the milk. Milk from grazing-based production systems including organic systems, therefore, has less saturated and more n-3PUFA and CLAc9t11 which is considered beneficial for health. The occurrence of natural trans FA (t11) in milk predominates with grazing whereas intensive feeding practices enhance t10-FA, with possible negative health effects. FA intake – output relations can differ among plant species due to rapid rumen passage rate or compounds protecting PUFA, resulting in more PUFA in milk. Methodological constraints for FA measurement in herbages are discussed. Trends in grazing and dairy farming systems and implications for milk FA composition are addressed.

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... Total mixed ration can also be easily offered to cows in confinement throughout the year, in line with the increase in herd size and demand for higher milk yield. As such, housing cows indoors has become more popular in certain regions of the world (Elgersma, 2015). An alternative to TMR is partial mixed ration, which is basically a TMR offered on a feed pad between bouts of grazing at pasture (Bargo et al., 2002). ...
... Conjugated linoleic acid isomers have been shown to reduce chemically induced tumors in the mammary gland, skin, colon, and forestomach in animal studies (Kelley et al., 2007). The cis-9,trans-11 isomer of CLA known as rumenic acid is a distinct feature of ruminant milk, biohydrogenated from linoleic and linolenic acids originating in the feed and enzymatically produced from vaccenic acid by desaturase in the mammary tissue (Mohammed et al., 2009;Elgersma, 2015). Sheep cheese naturally enriched with α-linolenic acid (ALA), CLA, and vaccenic acid given to adults with mild hypercholesterolemia was found to significantly increase the plasma concentrations of CLA, ALA, and eicosapentaenoic acid (EPA) as well as decreased low-density lipoprotein cholesterol (Pintus et al., 2013). ...
... Consumers typically perceive grass-fed or pasturebased farming positively, in terms of cow welfare and environmental sustainability (Ellis et al., 2009;Heerwagen et al., 2013;Elgersma, 2015;Armbrecht et al., 2019;Shortall, 2019). The importance of these 2 topics, cow welfare and sustainability, is predicted to continue rising in consumer acceptance of foods and in particular of dairy products (Britt et al., 2018). ...
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Grazing pasture is the basis for dairy production systems in regions with temperate climates, such as in Ireland, New Zealand, parts of Australia, the United States, and Europe. Milk and dairy products from cows on pasture-based farms predominantly consuming fresh grazed grass (typically classified as “grass-fed” milk) have been previously shown to possess a different nutrient profile, with potential nutritional benefits, compared with conventional milk derived from total mixed ration. Moreover, pasture-based production systems are considered more environmentally and animal welfare friendly by consumers. As such, there is significant potential for market capitalization on grass-fed dairy products. As competition in this space increases, the regulations of what constitutes as grass-fed vary between different regions of the world. With this in mind, there is a need for clear and independently accredited grass-fed standards, defining the grass-fed criteria for labeling of products as such, subsequently increasing the clarity and confidence for the consumer. This review outlines the numerous effects of pasture production systems on dairy product composition, nutritional profile, and sustainability, and highlights potential future methods for authentication.
... Regarding milk fat composition, when cows change from a pasturebased system (grass plus concentrate mix or grass plus total mixed ration: TMR) to 100% TMR, milk SFA increases in detriment of beneficial FA [44,45]. Meanwhile, when cows switch from TMR to a pasture-based feeding system, the healthy FA increases [41,[44][45][46]. Hence, during summer, an alternative mixed system consisting of one grazing session at night would improve milk fat composition, while at the same time reducing heat stress negative effects. ...
... Therefore, cows in a mixed system, even during the summer and overnight grazing, had higher concentration of CLA and linolenic (n-3) in milk than cows in confinement. These results ratify that pasture inclusion in the diet (main source of C18 as linolenic (n-3) and linoleic FA) [46] could increase FA intermediates (VA and RA) and therefore CLA proportion in milk [26,27]. Our results are also consistent with Morales-Almaraz et al. [61] and Barca et al. [41] who found higher amounts of n-3 in systems that include pasture compared to 100% TMR systems. ...
... In this sense, after change (M3), the GCHD increased the n-6/n-3 ratio to values considered inappropriate for human consumption (above 4/1), while GTMR+P maintained adequate values for human health, as suggested by Simopoulos [18]. Hence, this work highlights the importance of maintaining grazing at night in mixed systems during summer, as it leads to a fatty acid profile considered beneficial for human health, such as high n-3 and C18 : 2 (CLA) content, and low n-6/n-3 ratio [46,62]. In addition, overnight grazing in a mixed system could be a good management tool as it allows cows to better express their normal International Journal of Food Science behavior, while mitigating heat stress during daylight hours, enabling better welfare [42] and with lower feeding cost in comparison to confinement system [31,63]. ...
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This study is aimed at comparing the milk fatty acid profile (FAP) of cows that changed from a mixed system (MS) of double grazing plus total mixed ration (TMR) to a total confinement system (TCS, 100% TMR) with cows that changed to another MS with one overnight grazing plus TMR and compare with cows that were kept unchanged in TCS. The diet change was made in the second month of lactation. The milk samples were collected at one (M1-spring) and three months of lactation (M3-summer). Three treatments are as follows (each n = 10 ): confined cows fed with TMR throughout the period (GTMR), cows that changed from MS with double grazing plus TMR in M1 to TCS in M3 (GCHD), and cows that changed from a MS with double grazing plus TMR in M1 to a MS with overnight grazing plus TMR in M3 (GTMR+P). Unlike GTMR+P, GCHD improved milk production after change (increased 14% from M1 to M3), but milk FAP was impaired. In M3, conjugated linoleic acid (C18 : 2-CLA) in GTMR and GCHD was lower than GTMR+P ( p < 0.05 ), and linolenic (C18 : 3-n-3) was lower in GCHD than GTMR+P. Maintaining grazing in summer overnight sustained milk fat quality, evidenced by higher C18 : 3 (n-3); C18 : 2 (CLA); and n-6/n-3 ratio than cows that changed to TCS.
... Specifically, it reduced the content of C16:0 (between À6 and À10%) and SFA (approximately À5%) in dairy products of all studied animals (not significant for SFA in DG) and meat products of sheep (À5 and À6%, respectively) ( Table 4). This effect of fresh herbage in animal diets on reducing the C16:0 content of meat and dairy products is welldocumented under controlled conditions (Elgersma, 2015;Daley et al., 2010;Sinclair, 2007), although it appears to be stronger than that found in the present study (between À11 and À31% for both in DC) (Ferlay et al., 2006;Cabiddu et al., 2019). C16:0 is partially derived from intake, and its content is low in fresh herbage (Elgersma, 2015). ...
... This effect of fresh herbage in animal diets on reducing the C16:0 content of meat and dairy products is welldocumented under controlled conditions (Elgersma, 2015;Daley et al., 2010;Sinclair, 2007), although it appears to be stronger than that found in the present study (between À11 and À31% for both in DC) (Ferlay et al., 2006;Cabiddu et al., 2019). C16:0 is partially derived from intake, and its content is low in fresh herbage (Elgersma, 2015). It is also partially synthesised de novo in the mammary gland and partially inhibited when high amounts of PUFA are transferred to the mammary gland (Elgersma, 2015). ...
... C16:0 is partially derived from intake, and its content is low in fresh herbage (Elgersma, 2015). It is also partially synthesised de novo in the mammary gland and partially inhibited when high amounts of PUFA are transferred to the mammary gland (Elgersma, 2015). In our study, the C16:0 and SFA content decreased by respectively À0.2 and À0.1% with per unit increase in the fresh herbage proportion of animal diet, regardless of the PC (Table 3). ...
Article
In the last decades, a large body of evidence has highlighted the major role of feeding management practices in improving specific nutritional, technological and sensory quality traits of ruminant products. However, results have been mostly obtained under controlled conditions, and have been rarely validated on-farm. Therefore, a quantitative review was conducted to quantify the effects of on-farm feeding management practices on carotenoids, fat-soluble vitamins, colour, fatty acids (FAs), terpenes and sensory properties in the main animal product categories (PCs): dairy products from cattle (DC), sheep (DS) and goat (DG), and meat from cattle (MC) and sheep (MS). Four feeding scenarios were selected according to the consistency of on-farm studies in the literature: (a) feeding "Fresh herbage" instead of conserved forages; (b) ban any form of silage ("Silage-free"); (c) ban maize silage ("Maize silage-free"); (d) feeding forages from permanent grasslands rich in species or plant secondary metabolites (PSMs) ("PSM-rich permanent grassland"). Feeding fresh herbage increased the concentration of carotenoids, fat-soluble vitamin, n-3 FA, rumenic acid, and branched chain FA (BCFA), and reduced the concentration of saturated FA, for all PC, with overall stronger effect for dairy products than for meat. The texture of meat and dairy products was marginally affected, whereas feeding fresh herbage decreased lactic and increased vegetal notes in DC. The "Silage-free" feeding scenario resulted in increased vaccenic acid, rumenic acid, BCFA, and C18:3n-3 in DC. The "Maize silage-free" feeding scenario lowered n-6 FA whereas increased n-3, rumenic acid and BCFA concentrations in DC. Feeding ruminants with forages from "PSM-rich permanent grasslands" increased monounsaturated FA, n-3 FA and rumenic acid and decreased n-6 FA in dairy products, and only marginally affected meat FA composition. The DC from "PSM-rich permanent grasslands" showed higher intense, spicy and animal notes. Overall, the differences between feeding management practices observed on farm were smaller than those observed under controlled trials. Several confounding factors, not controlled when operating under on-farm conditions, could be at the origin of these divergences (i.e. mixed diets, forage characteristics, animal-related factors). This review confirmed that farming practices may differently affect several quality traits of ruminant products. It also highlighted the uneven knowledge on the effect of feeding management depending on the PC: larger for milk than for meat and decreasing when moving from cattle to sheep and from sheep to goat.
... Grazing is an important management practice in terms of, for example, the nutrition of fresh forage intake, animal health [1], animal well-being, natural behavior [2], landscape values, and grassland biodiversity [1,3,4]. Grazing dairy cows has been practiced for a long time as a strategy for improving animal welfare and milk quality [5], lessening oxidative stress [2], and economic purposes [6,7]. ...
... Grazing is an important management practice in terms of, for example, the nutrition of fresh forage intake, animal health [1], animal well-being, natural behavior [2], landscape values, and grassland biodiversity [1,3,4]. Grazing dairy cows has been practiced for a long time as a strategy for improving animal welfare and milk quality [5], lessening oxidative stress [2], and economic purposes [6,7]. ...
... Many factors influence the compositions of milk including but not limited to the nutritional values of feed, nutrition level, feeding management, stress source and severity, genetic, environment, season, stage of lactation, reproductive and productive status of the animals, age, and BW of the animals, etc. Improving milk quality has the dual purpose of increasing both the nutritional value and the commercial value of the milk (i.e., low worker and feed costs). In this regard, increasing the levels of poly-unsaturated fatty acids (PUFAs), particularly omega-3 PUFA, in milk is desirable in dairy animals [1,6]. Although previous studies have investigated the effects of grazing on the welfare [4,14,15] and milk of dairy animals [16,17], to what extent grazing can positively impact milk characteristics without negatively influencing production performance in high-yielding lactating cows needs further exploration. ...
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The effects of grazing lactating cows in mountainous areas for 12 and 24 h compared with the confined indoor system were evaluated by examining the overall milk fatty acid and cortisol. Twenty-one dairy cows were allocated to three treatment groups: (1) control (confined management system in a free-stall barn; TMR based), (2) grazing for 12 h (12hG; TMR plus grazing pasture), and (3) grazing for 24 h (24hG; pasture-based feeding system). Dry matter intake was higher in the control and 12hG groups than in the 24hG group. The yields of total milk and the 3.5% fat-corrected milk were the lowest in the 24hG group. Milk fat was the highest in the 24hG group and higher in 12hG compared with the control group. Milk protein and lactose levels were the highest in the 12hG group. The highest somatic cell count was observed in the 24hG group. The saturated fatty acid levels were higher in the control group compared with the 12hG and 24hG groups. There was no difference in overall mono-unsaturated fatty acids between 12hG and 24hG groups. Poly-unsaturated fatty acids were higher in the 12hG group compared with the control and 24hG groups. There was no difference in omega-6 (ω-6) fatty acids among the groups, and omega-3 fatty acids were higher in the 12hG group than in the control group. Milk cortisol was the highest in the 24hG group and higher in the control group compared with the 12hG group. Taken together, grazing for 12 h is advisable for farms that have access to mountainous areas to improve the milk fatty acid profile and decrease the stress levels in high-yielding Holstein lactating cows.
... The fatty acid composition of cow's milk has recently become less favorable to human health due to changes in feeding pattern, based on large amounts of concentrates and silage and less or even elimination of grazing (Elgersma and Tamminga, 2006). Pasture is an important source of PUFA (especially C18:3 n-3, which represents over 60% of total FA -Mierliță et al., 2017) for ruminants, but the fatty acid composition of milk fat is influenced by its nutritional value of pasture, floristic composition, vegetation stage (season) and quantity consumed (Elgersma, 2015). The use of pasture in cow feed has a positive impact on the nutritional quality of milk, increasing the content of some components beneficial to human health, such as omega-3 FA, vaccenic acid (VA, C18:1 trans-11) and conjugated linoleic acid (CLA, C18:2 cis-9 trans-11), in the same time reducing the levels of omega-6 FA and palmitic acid. ...
... Significantly higher percentages of functional fatty acids were recorded in the fat in milk obtained from animals kept on pasture (Mierliță, 2017). While feeding TMR cows led to increased concentrations of SFA (saturated FA), the fat in the milk obtained from the pasture has a lower content of SFA and a higher content of unsaturated FA (UFA) with a higher concentration of PUFA; but also, an n-6/n-3 FA ratio and an improved thrombogenicity (TI) and atherogenicity (AI) index (Alothman et al., 2019) and lower concentrations of hypercholesterolemic FA (C12:0, C14:0 and C16:0) (Chilliard et al. 2007;Elgersma, 2015). ...
... Numerous studies have shown that milk obtained from grazing cows contains higher levels of natural antioxidants (tocopherols and retinol) than that obtained from animals fed intensively with TMR, due to the fact that the conservation of green fodder and processing in hay and silage, causes the degradation and inactivation of many bioactive compounds (Elgersma, 2015;Mierliţă et al., 2017). The concentration of α-tocopherol in pastures is 12| VOLUME 78 ISSUE 2 | NOVEMBER 4-5 times higher than that found in a TMR (NRC, 2001). ...
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This bibliography review analyzes the effects of different feeding regimes of cows the nutritional and sanogenic quality of milk, with a particular emphasis on milk content in functional fatty acids and non-enzymatic lipophilic antioxidants. Thus, using suitable feeding regimes of cows, fatty acid (FA) profile of milk fats can be improved by increasing the concentration in functional FA (C18:1 trans-11, vaccenic acid; C18:3 n-3, acid linolenic and C18:2 cis-9 trans-11, isomer of conjugated linoleic acid), considered as beneficial for consumer’s health. These suitable feeding regimes of cows aim using green fodder (pastures), preserving the fodder by drying or silage, supplementing the food with fats rich FA polyunsaturated (PUFA) and ensuring an optimal ratio between volume and ration concentrates. Milk yielded from grazing cows shows a considerably higher concentration of functional FA and lipophilic antioxidants (tocopherols, retinol and carotenes) and a lower content of saturated FA compared to that yielded from cows fed in shelter with TMR (total mixed ration). Also, hay-based feed rations, mainly those containing small amounts of concentrates or those supplemented with vegetable fats, ensure a milk yield with a fatty acid profile more favorable for human health and a better oxidative stability of compared to those with feed-based rations on silage or those high in concentrates.
... The differences in total mixed rations in this experiment are reflected in the fatty acid profiles of milk, because the concentration of fatty acids in milk are closely related to the diet provided to animals [43]. The results obtained show that fresh forage is the main source of polyunsaturated fatty acids in the diet of ruminants, according to others' studies [44][45][46]. In the fatty acid profile of milk, strong differences were observed attending to the type of silage in the diet and to the management with and without grazing. ...
... However, in the present study, the milk from cows fed IR ration without grazing had the lowest concentration of unsaturated fatty acids, but it had only higher protein concentration than the other treatments while no differences were observed in milk yield nor fat concentration among treatments. The fresh forage is especially rich in linolenic acid, which is extensively biohydrogenated in the rumen to vaccenic acid (18:1 trans-11) that subsequently is desaturated to CLA in the mammary gland [45]. A low n-6/n-3 ratio is indicative of a grass-based diet [45]. ...
... The fresh forage is especially rich in linolenic acid, which is extensively biohydrogenated in the rumen to vaccenic acid (18:1 trans-11) that subsequently is desaturated to CLA in the mammary gland [45]. A low n-6/n-3 ratio is indicative of a grass-based diet [45]. This fact is according with the results of this study, where the lowest n-6/n-3 ratio correspond to milk produced with the grazing management. ...
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Dairy systems based on grass and forages are widely spread throughout the European Atlantic Arc and they have an influence on milk quality. Likewise, legumes are a key element in the farms to improve cows’ diet and farm feed self-sufficiency. The aim of this study was to evaluate the effect of the legumes in the diet and the feeding system (pasture-based vs. confined) on milk production and composition. An assay was performed with 18 Friesian cows randomized into two management groups (grazing or confined). Three total mixed rations based on Italian ryegrass, faba bean or field pea silages were offered ad libitum for nine continuously housed cows or during two hours after each milking for another nine grazing cows. Regardless of type of silage, grazing cows had higher dry matter intake and milk production than confined cows. Likewise, grazing cows produced milk with a lower concentration of protein and urea than confined cows. The dairy cows fed total mixed rations based on both legume silages had a milk fat with a higher proportion of unsaturated fatty acids, especially with the inclusion of faba bean silage in the diet. The results demonstrate that the profile of fatty acids and antioxidants is related to the feeding system in dairy cows. Grazing directly influenced the composition of milk, decreasing the proportion of saturated fatty acids and increasing the content of unsaturated fatty acids, as CLA, and the antioxidants, as lutein and β-cryptoxanthin.
... However, the positive correlation found between fresh herbage intake and milk linolenic acid content (r = 0.42; p < 0.01) partially explains the high and opposite loadings values of UFA and SFA, thanks to the plant's PS (GW and FW) with a pivotal effect on the fatty acid precursor content in the herbage [14,53]. In addition, a good correlation was found between herbage intake and milk C18:2 t11c15 content (r = 0.60; p < 0.01) and between linolenic acid and C18:2 t11c15 milk content (r = 0.72; p < 0.01); it is well known that an increase in herbage intake leads to an increase in linolenic acid (ALA) and C18:2t11c15 in milk, as also reported by [56]. The BH intermediate (in particular, trans C18:1 isomers) with positive loadings were all related to the availability in the diet of linolenic acid (ALA), in agreement with [57], even if linoleic acid (LNA) and ALA showed low loadings values for PC2. ...
... The BH intermediate (in particular, trans C18:1 isomers) with positive loadings were all related to the availability in the diet of linolenic acid (ALA), in agreement with [57], even if linoleic acid (LNA) and ALA showed low loadings values for PC2. A positive correlation between total trans C18:1 trans isomers (r = 0.70; p < 0.01) and milk ALA content was detected due to a higher intake of daily fresh pasture herbage, which increases ALA intake, as also reported by [20,57] and is associated with an increase of total C18:1 trans [56]. In spite of any significant effect of hay or concentrate supplementation on PC scores, we found a positive correlation between hay intake and C15:0i, (r = 0.52; p < 0.01) as a probable consequence of the association effect of the concentrate. ...
... This is also in line with the relationship found between ferulic acid and ALA (r = 0.41; p < 0.01) since linolenic acid represents the main fatty acid in fresh herbage. A negative correlation was found between CLA c9t11 and the plant's phenological stage, when passing from the growing and flowering to the maturity stage, as it probably resulted in a decrease in the precursor [56]. ...
Article
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The fatty acid profile, vitamins A and E, cholesterol, antioxidant power colour and the phenols profile of Sarda sheep milk from 11 commercial sheep flocks managed under permanent grassland were investigated. In each farm, the structural and managerial data and milk samples were collected during four periods (sampling dates, SD): January, March, May, and July. Data from the milk composition (fat, protein, casein, lactose, and somatic cell count), 68 fatty acids, 7 phenols, 1 total gallocatechin equivalent, ferric reducing antioxidant power, vitamins A and E, cholesterol, degree of antioxidant protection, and the colour (b *, a * and L *) were analyzed by multivariate factorial analysis using a principal component analysis approach. A proc mixed model for repeated measurement to point out the studied factors affecting significant macro and micro milk composition was also used. Only the first five components were detailed in this paper, with approximately 70% of the explained variance detected. PC1 presented the highest positive loadings for milk lactose, de novo FA synthesis and the BH intermediate, whereas OBCFA had negative loadings values. The PC2, LCFA, UFA, MUFA, vitamins E, and DAP showed positive loadings values, while SFA had a negative value. The PC3 showed a high positive loading for total phenols and non-flavonoids. PC4 presented a high positive loading for the milk macro-composition and negative values for n-3 FAs. The PC5 is characterized by high positive loadings for the a * and L * colour parameters whereas negative loadings were detected for the milk flavonoids content. These preliminary results could help to establish future threshold values for the biomarkers in milk sourced from grazing dairy sheep in natural, permanent pasture-based diets.
... Grass silage becomes the most abundant feed source during the winter months when cows are housed indoors. The effect of dietary systems has been demonstrated to have an impact on the composition and quality of milk and in particular the fatty acid (FA) profile, where substantial changes can be observed with changing nutrition [7]. The depletion of milk saturated fatty acids (SFA) and increase in the more nutritionally beneficial unsaturated fatty acids (UFA) and conjugated linoleic acids (CLA) has been shown to result from increasing levels of pasture in the diet [5,[8][9][10]. ...
... Factors including a lack of grazing infrastructure, land cost and availability, shorter growing seasons, access to automatic milking systems, trained labour, weather variability and a lack of grassland grazing knowledge are reasons why countries might adopt this approach [14]. Indoor TMR systems typically result in a greater management of nutrition and dry matter intake (DMI) to support the energy requirements of the high productivity dairy cows associated with TMR systems, which cannot always be achieved through pasture diets [7,15]. Over 90% of intensive dairy farms in the United States operate a TMR system [13] and it has also become more conventional in Middle Eastern countries, Japan, China, and parts of Europe despite the higher labor [7] and feed costs, the latter of which can rise to above 50% of the total operating costs [16]. ...
... Indoor TMR systems typically result in a greater management of nutrition and dry matter intake (DMI) to support the energy requirements of the high productivity dairy cows associated with TMR systems, which cannot always be achieved through pasture diets [7,15]. Over 90% of intensive dairy farms in the United States operate a TMR system [13] and it has also become more conventional in Middle Eastern countries, Japan, China, and parts of Europe despite the higher labor [7] and feed costs, the latter of which can rise to above 50% of the total operating costs [16]. Housing animals all year round offers the opportunity to condense feeding times, while the increased DMI rates allow more time for "high priority behaviour" such as resting and ruminating [15,17]. ...
Article
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Seasonal calving, pasture-based dairy systems are widely practiced in countries with a temperate climate and plentiful rainfall such as Ireland and New Zealand. This approach maximizes milk production from pasture and, consequently, is a low-cost, low-input dairy production system. On the other hand, the majority of global milk supply is derived from high input indoor total mixed ration systems where seasonal calving is not practiced due to the dependence on ensiled silages, grains and concentrated feeds, which are available year-round. Synchronous changes in the macro and micronutrients in milk are much more noticeable as lactation progresses through early, mid and late stages in seasonal systems compared to non-seasonal systems—which can have implications on the processability and functionality of milk.
... Elgersma [6] and Barca et al. [7] reported that the use of pastures in dairy cattle feeding leads to an increase in mono-unsaturated FAs (MUFAs) and polyunsaturated FAs (PUFAs) in milk fat, especially VA, CLA, and n-3 FA, and a decrease in FA concentrations with hypercholesterolemiant effect (C12:0, C14:0, and C16:0), compared to cattle fed using TMRs. However, feeding dairy cattle exclusively on pastures limits dry matter intake (DMI), which lowers milk production compared to the TMRs [8]. ...
... α-tocopherol and carotenoid concentrations in feed influence their concentration in the milk produced [15]. Pastures are a natural source of antioxidants and PUFAs (mainly ALA, C18:3 n-3) for dairy cows, directly influencing the milk content in these bioactive compounds [6]. The milk yielded from pasture, compared to that yielded from TMRs used in feeding cattle, has a higher content in terms of unsaturated FAs with health benefits (VA, CLA, ALA) and antioxidants (β-carotene, lutein, retinol, tocopherols, phytol) [4]. ...
... The results of this study related to the chemical composition of biomass from pastures are in line with those reported by Radonjic et al., [29] and Bohacová et al. [30], who stated that the pasture content in crude fiber increased with the plants' vegetative growth, while the protein content decreased. According to this study, a strong positive global linear relationship was ascertained between the crude protein and the ALA (C18:3 n-3) content in pasture [6]. The DM content increase in the pasture, is mainly due to the crude fiber increment, resulting in a reduction in energy content, which is the main limiting factor for the milk yielded from pasture [31]. ...
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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.
... As consumer awareness of food choices increases with respect to health choices, animal welfare and environmental impact of food, the milk quality from pastoral grazed systems is becoming important. This is driven mainly by the elevated concentration of health promoting fatty acids (FA) in ruminant products from grazed systems compared with those from concentrates or conserved feed-based systems (Elgersma, 2015). Specifically, nutritionists have indicated interest in milk FA profile as some individual FA have implications on human health. ...
... More studies are needed to explore the biological activity of condensed tannins found in chicory herbage. While diet PUFA are extensively biohydrogenated in the rumen, it has been shown that increasing their concentration in the diet of dairy cows can substantially improve both their concentration and that of CLA in ruminant-source foods (Jenkins et al., 2008;Elgersma, 2015;Toral et al., 2018). As a result, it is desirable to feed diets high PUFA to increase their concentration in the milk. ...
... Upon entering the rumen, lipase, produced mainly by ruminal bacterium Anaerovibrio lipolytica, hydrolyses the ester linkages in the complex lipids causing the release of non-esterified FA with free carboxyl groups in the ruminal digesta that can be hydrogenated by other rumen microbes (Dawson et al., 1977). The rate and level of hydrolysis of the ingested FA is generally high [>85%; (Lock and Bauman, 2004)], depending on factors such as ruminal pH, feed intake level and rumen retention time of lipids (Lock and Bauman, 2004;Elgersma, 2015;Toral et al., 2018). ...
Thesis
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As consumers interest in the environment and the source and quality of their functional food increase, milk quality from pastoral grazed systems is becoming increasingly important. Additionally, strategies to diminish the loss of nitrogen (N) associated with the traditional perennial ryegrass/white clover [Lolium perenne L./Trifolium repens L.; (RGWC)] are being considered. Recent research has identified the value of forage herbs as a pathway to mitigate N losses in the environment. However, the current research has focused on the role of plantain (Plantago lanceolata L.) with little emphasis on the alternative herb chicory (Cichorium intybus L.). Chicory is known to have high palatability and healthy fatty acid (FA) profile, but little is known about the best management practices for chicory in an irrigated dairy environment or about the animal response in relation to milk quality and N partitioning. The main aim of the thesis was to investigate the effects chicory-based herbage has on urine N excretion, milk production and milk FA composition of dairy cows, as well as to understand the mechanisms leading to the variation in milk FA of cows grazing chicory-based herbage and those grazing RGWC-based herbage. A secondary aim was to investigate the effect of grazing management (defoliation intensity, severity and timing) before and after vernalisation on morphology, functional traits, herbage DM production and biochemical composition of chicory and the subsequent effect on milk production and milk FA composition. Two grazing experiments and one agronomy experiment were conducted on irrigated chicory-based pastures grazed by dairy cows. The first experiment compared milk production, milk FA, urination patterns, and N use efficiency of cows grazing chicory, plantain, or RGWC. Fifty-four Friesian x Jersey cows in late lactation were blocked into replicated groups of six cows and offered one of three pasture types. Automated urine sensors measuring urine volume and timing were affixed to approximately 10 random cows per treatment for 24 h. Milk yield was similar for all treatments, but milk solids production (protein + fat) were greater from cows grazing chicory than RGWC (1.86 vs 1.72 kg MS/cow.day, P < 0.01) while plantain was intermediate (1.76 kg MS/cow.day). Milk produced from cows grazing chicory or plantain contained greater proportions of omega-3 FA than that from cows on RGWC (P < 0.01), despite lower omega-3 FA in herbage. The traditional RGWC increased the percentage of conjugated linoleic acid (CLA; isomer C18:2 c9 t11) and vaccenic acids in milk compared with those of milk produced from herbs (P < 0.01). This reflected the greater percentage of α-linolenic acid in RGWC (P = 0.02) than in forage herbs. There was large variation in urine event volume (0.13–11.6 L per event), though mean urine volume per event was similar for each treatment (3.01 ± 0.3 L per event; P = 0.24). Water, sodium and potassium intakes from herbage was greatest for chicory compared with plantain or RGWC. Frequency of urination increased with increasing water, sodium and potassium intakes and cows grazing chicory and plantain urinated more often (28.6 and 21.2 events/cow.day, respectively) than those grazing RGWC (13.9 events/ cow.day, P < 0.05). Consequently, cows grazing chicory excreted 1.5 and 2.4 times more urine per day (P < 0.01) than cows grazing plantain and RGWC, respectively. Apparent N intake was similar between cows grazing chicory and RGWC, but greater than cows grazing plantain. However, urinary N (UN) concentrations from cows grazing chicory and plantain were similar (P > 0.05), but substantially lower than RGWC (1.3 vs 4.8 g/kg; P < 001). The reduction in UN in cows grazing herbs was mainly attributed to increased number of urinations, which resulted in urine dilution. The combination of similar urine volume per event in all three forages, frequent urinations and substantially lower UN concentration in cows grazing the forage herbs indicate a benefit from forage herbs to reduce N load onto pasture. Overall, the findings from this first experiment demonstrated the potential benefit of chicory to alter milk FA composition, however, the mechanisms leading to the increase in beneficial FA in milk of cows offered the chicory were not clear and needed further investigations. Additionally, while the study demonstrated that sole diets of chicory elevated urination frequency and reduced UN concentration when compared with RGWC, practically however, it is unlikely that farmers will grow large areas of their farm in chicory and therefore more strategic management of chicory to alter animal response (milk production, milk FA composition and urine N excretion patterns) warranted investigation. The second grazing experiment investigated the effects of including chicory into the traditional feeding regime of ryegrass/white clover, and time of its allocation on milk production, rumen fermentation, and FA composition of milk and rumen digesta of dairy cows. Nine groups of four cows were allocated one of three replicated feeding regimes: (1) RGWC, (2) RGWC + morning allocation of chicory (CHAM), and (3) RGWC + afternoon allocation of chicory (CHPM). One cow per group had a rumen cannulae fitted. Treatment did not affect total grazing time or estimated dry matter intake, but cows ruminated less when fed chicory than RGWC. Allocating chicory in the afternoon elevated milk production compared with RGWC and CHAM. Similar to the first grazing experiment, milk from cows grazing chicory contained greater concentrations of polyunsaturated FA (PUFA) such as C18:3 c9, 12, 15 and C18:2 c9, 12 than those on RGWC. As with milk, rumen digesta concentration of PUFA increased when cows grazed on chicory rather than RGWC, which corresponded with lower concentrations of intermediate vaccenic and biohydrogenation end-product stearic acid for cows grazing on chicory. Mean ruminal pH was lower for cows offered chicory than those on RGWC, reflecting greater rumen concentrations of volatile fatty acids (VFA) for cows fed chicory. Apparent N intake was unaffected by treatment (P = 0.151). Chicory inclusion increased urination frequency by up to 69%, resulting in a 33% mean decline in UN concentration, independently of time of allocation. A decline in UN concentration was detected following greater urination activity, with cows offered CHAM having lower UN concentration than cows offered CHPM or RGWC (P ≤ 0.05) at 2000 h. The milk FA and urine excretion results of this second grazing experiment were consistent with the previous experiment showing that strategic use of chicory can achieve desired outcomes. The basis for grazing management decisions in this second experiment was informed by detailed agronomic investigation of chicory. Concurrent agronomy studies of chicory were conducted alongside the grazing experiments. The agronomy experiment measured functional traits, morphology, herbage production and biochemical composition of chicory under irrigated field conditions before and after vernalisation in Canterbury, New Zealand. The experimental site was laid out in a complete randomized block design with four replications where two regrowth intervals and two defoliation heights were applied. Regrowth interval had a stronger influence over functional traits and herbage production than defoliation height, with more pronounced effects after vernalisation. Plants managed under shorter regrowth intervals had narrower roots with lower concentration of sugars than plants under longer intervals, which might compromise their longevity. In addition, plants managed under shorter intervals remained mostly vegetative with heavier and longer leaves, though with reduced photosynthetic capacity than those managed under longer intervals. The thermal time to initiate stem elongation in plants managed under longer intervals was ~274 growing degree-days, with a mean stem elongation rate increasing linearly at 1.4 ± 0.08 mm/growing degree-days. In terms of nutrient and FA composition of chicory herbage, the findings showed significant interaction effects between phenology stage and regrowth interval. Before vernalisation, the FA and nutrient components exhibited little variation with regrowth interval and defoliation height irrespective of time of day. After vernalisation, concentrations of linoleic, linolenic and total FA declined, by 50, 74 and 63% respectively. Furthermore, extending the regrowth interval from 300 to 600 growing degree-days after vernalisation caused a decline of 28% of linoleic, 40% of linolenic and 33% of total FA concentrations. Generally, there were little to no diurnal changes in the main FA’s with the exception of linoleic and oleic acids after vernalisation (P < 0.01). Vernalisation decreased CP, digestibility and ME, while fibre contents increased. Between morning and afternoon there were general declines in CP and fibre contents as well as increases in soluble sugars and non-fibre carbohydrates of the herbage regardless of vernalisation. While feed quality was generally poorer in vernalised chicory, the concentration of polyunsaturated FA and digestibility can be enhanced by shortening the regrowth interval. The increase in FA and feeding value in afternoon herbage may enhance both productivity and quality of the milk while minimizing environmental risks associated with pastoral farming. Overall, the thesis shows, for the first time, that chicory is a high moisture forage crop that increases urination frequency and dilutes the N concentration of the urine when included into that traditional grazing regime with RGWC. This demonstrates the potential role of chicory in promoting environmentally sustainable pastoral dairying systems. Timing of chicory allocation affected the diurnal patterns of urine excretion, but not the daily urine excretion output, indicating that chicory could be allocated anytime during the day without compromising the potential environmental benefits. Including chicory into a traditional grazing regime has the potential to increase milk production of dairy cows and allocating chicory during the afternoon is a useful strategy that can translate to improved milk production. The thesis further confirmed that feeding chicory to dairy cows enhanced the concentration of functional FA in milk. The lower rumen pH, lower concentration of biohydrogenation intermediate and end product vaccenic and stearic acids, respectively, and the elevated concentration of PUFA in the rumen of cows fed chicory suggested reduced biohydrogenation and may explain the elevated concentration of PUFA in the milk of cows fed chicory compared with those fed RGWC. In terms of managing chicory pastures, the experiments conducted demonstrated the potential trade-offs between herbage production and feeding value as chicory plants exposed to longer regrowth intervals accumulated larger amounts of aerial mass and reduced the highly nutritious leaf proportion of the herbage. Alternating frequent and infrequent defoliation regimes might be used to optimise vegetative growth, root reserves, and pasture persistence. A key finding from the thesis quantified the growing degree-days to initiate stem elongation post vernalisation, which provides management directive for timing of defoliation of chicory in order to maintain feed quality for grazing livestock.
... Also sampling of maize silage and concentrate was at the beginning and end of each experimental period and a composite sample used for analyses. The samples were dried in a draught oven at 55°C to constant weight with the goal to minimize the loss of nutrients following methods proposed by Boufaïed et al. (2003) and Elgersma (2015), ground through a 1mm sieve and kept in airtight plastic vials until their analysis. ...
... The season of the year also exerts an effect on the fatty acid composition of pastures and forages destined for feeding the dairy herd, which affects the composition of milk fatty acids, especially on the content of those with a proven beneficial effect on the human health (Nantapo et al. 2014;Elgersma 2015;Vieyra-Alberto et al. 2018). ...
... Forage: concentrate ratio in the work herein reported was 65:35, of which maize silage represented 45.8 % and 35.1 % commercial concentrate with just 19.1 % of total DMI from grazed pastures. The high maize silage and concentrate intake (81 % of total DMI) probably affected microorganism activity in the rumen, and eventually in the PUFA contents in milk (Elgersma 2015 Observed results lead to accept the hypothesis that kikuyu grass pastures in winter, are comparable to pastures originally sown to tall fescue, both associated with white clover and oversown with annual ryegrass, in terms of agronomic variables and herbage composition; as well as in cow performance, and the fatty acid profile of milk under daytime grazing of these pastures complemented with maize silage and concentrates. ...
Article
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The work herein reported closes the evaluation of the role of kikuyu grass in small-scale dairy systems in the highlands of Mexico. The objective was to compare the productive response of vacas lecheras en pastoreo continuo de kikuyu (Cenchrus clandestinus) with a sown frost-resistant tall fescue (Lolium arundinaceum) during the winter-spring dry season in dairy systems and determine the fatty acid profile of feeds and milk. An on-farm double cross-over experiment with three periods the 14 days each was undertaken with eight Holstein cows randomly assigned to treatments sequence. Treatments were daytime grazing for 8 h/d of a Cajun II endophyte free tall fescue pasture invaded by kikuyu grass (CJ) or a naturally invaded kikuyu grass pasture (KY), both associated with white clover (Trifolium repens) and annual ryegrass (Lolium multiflorum). Cows were supplemented in pens with 6.0 kg DM/cow/day with maize silage and 4.6 kg DM/cow/day of commercial concentrate. The fatty acid profiles of feeds and milk were determined by gas chromatography. There were differences (P<0.05) for net herbage accumulation and chemical composition between pastures, but not for in vitro digestibility or estimated metabolizable energy. In animal variables, protein content in milk was higher in KY (P<0.05). There were significant differences (P<0.05) among experimental periods for milk fat content and milk urea nitrogen with the highest values in Period 3. Pasture DM intake was lowest (P<0.05) in Period 3. In terms of fatty acid content, there were significant interactions (P<0.05) for vaccenic acid (C18:1t11) and linoleic acid (C18:2c9c12) with the highest values in Period 3. Linolenic acid (C18:3c9c12c15) was higher in milk when cows grazed KY and significantly higher (P<0.05) in Period 3. It is concluded that kikuyu pastures complemented with maize silage and concentrates in winter-spring perform as tall fescue pastures in the season of herbage scarcity. Milk from cows grazing kikuyu grass pastures complemented with maize silage and concentrates has a higher content of linolenic fatty acid and an atherogenic index favorable for human health.
... Plants respond to low growth temperature by increasing UFAs (especially PUFAs) to maintain membrane integrity [72][73][74]. PUFAs play a role in maintaining membrane fluidity in the chloroplast as well as other organelles [75], which is an important plant response to low temperature stress. Forages are often the main source of PUFAs in animal feed, and forages with higher PUFAs can modify the FA profile in meat or dairy products [76,77]. ...
... Milk's FA profile is of prime importance because it is a significant part of the human diet [75] and ultimately depends on the FA profile of the animal's diet [78]. PUFA contains two major FAs (18:2n-6 and 18:3n-3) in forage. ...
Article
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Intercropping systems could be a potential source of nutrient-rich forage production in cool climates on podzolic soils common in boreal ecosystems. In this study, we evaluated the effects of corn–soybean intercropping (IC) on the nutritional quality of forage. Two silage corn varieties were cultivated as monocropping (MC) or were intercropped with three forage soybean varieties using a randomized complete block design. IC significantly increased the crude protein (22%) and decreased the acid detergent (14%) and neutral detergent (6%) fibers. Forage net energy, total digestible nutrients, ash, dry matter intake, digestible dry matter and relative feed value were also significantly increased (p ≤ 0.05) in the IC treatments compared to corn MC. The macro and micro nutrients were higher in IC than corn MC. Intercropping increased the omega 3 fatty acid (FA) contents (67%) compared to corn MC. IC also increased the active microbial community in the plant root zone, which may contribute to the improvement in forage nutritional quality because the active soil microbial community composition showed significant correlations with soluble sugars, soluble proteins and potassium contents of the forage. These results demonstrate that corn–soybean IC could be a suitable cropping system to increase the nutritional quality of forage cultivated on podzols in boreal climates. The resultant forage has the potential to be a source of high-value animal feed for livestock production in cool climate regions of the world.
... The difference observed in the linoleic acid amount was directly linked to the higher n6/n3 ratio found in BS (3.17) than in AS (1.67) samples. The n6/n3 ratio in milk essentially depends on concentrations of linoleic (n6) and α-linolenic (n3) acids [45]. The n6/n3 ratio, well known as a healthy index to evaluate the quality of food fat, in dairy products can be improved (i.e., decreased) by shifts in cows diet, particularly enhancing the consumption of fresh grass, such as it happens in the production of alpine milk [32,45]. ...
... The n6/n3 ratio in milk essentially depends on concentrations of linoleic (n6) and α-linolenic (n3) acids [45]. The n6/n3 ratio, well known as a healthy index to evaluate the quality of food fat, in dairy products can be improved (i.e., decreased) by shifts in cows diet, particularly enhancing the consumption of fresh grass, such as it happens in the production of alpine milk [32,45]. Accordingly, the n6/n3 ratio was already shown to reach values more than two times higher in conventional milk compared with extensive or pasture-based milk [46,47]. ...
Article
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The production systems linked to mountain animal husbandry have had an environmental, social and cultural role in recent years. Zootechnical systems based on feeding strategies, such as pasture grazing and grass-fed strategies, contribute to a significant increase in the relative amounts of favorable fatty acids (FAs) in animal products, indicating their ability to improve the long-term health of consumers. In this study, we compared different feeding strategies in two small mountain farms in the Piedmont Alpine region, Italy. Particularly, during the summer season, the two farms were distinguished by the exclusive employment of Alpine pasture (farm A), assumed as the best way to improve the quality of the FA profile in milk vs. the supply of daily fresh cut mountain grass plus a reduced implementation with hay and concentrates directly in the barn (farm B). The milk fatty acid profile was analyzed using gas chromatography. The results showed the high quality of alpine milk collected in the two farms. Even with some differences, particularly evidenced when comparing the summer diets, the milk FA profiles in farm A and farm B were favorable from a nutritional point of view in both seasons. Milk samples obtained using the exclusive employment of alpine grazing during summer were represented by an FA profile of higher quality (lower saturated FAs, higher branched FAs and monounsaturated FA, favorable n6/n3 ratio). However, milk obtained using the integrated strategy (fresh grass plus concentrates in the barn farm B) resulted in a more homogenous composition during the summer season, with a higher concentration of polyunsaturated FAs. These outcomes suggested that the integrated strategy, even if related to a lower ability in improving milk FA profile, could represent a valid and cost-effective alternative for mountain farmers to obtain an overall superior quality of milk, which was not strictly linked to the grazing practice. The multivariate analysis showed that information contained in the milk FA profile may provide a valuable tool that can distinguish mountain-grass-based diet.
... Milk produced from cows fed fresh grass is characterized by elevated proportions of polyunsaturated fatty acids (PUFA) such as α-linolenic acid (ALA; C18:3n3), conjugated linoleic acids (CLA), especially rumenic acid (RA; C18:2c9t11) and vaccenic acid (VA; C18:1t11) (Dhiman et al., 1999;Leiber et al., 2005a). Diet is the main factor affecting milk FA composition (Elgersma, 2015) where a strong relationship between the proportion of fresh grass and CLA content in milk exists (Couvreur et al., 2006;Bär et al., 2020). Other factors such as season (Auldist et al., 1998;Rugoho et al., 2014), stage of lactation (Auldist et al., 1998) and grass composition (Collomb et al., 2002;van Dorland et al., 2008) also influence the milk fatty acid composition. ...
... A number of milk FA were influenced by the feeding system, but less than expected (Table 2 and online Supplementary Tables S2 and S3). Milk from grass-fed dairy cows typically has high proportions of PUFA, ALA and CLA (Dhiman et al., 1999;Elgersma, 2015). This was confirmed by the present study. ...
Article
For this research communication our objective was to investigate to what extent milk coagulation properties and milk fatty acid (FA) composition were affected by different feeding systems, season and their interaction. Eighteen cows in total were subjected to one of three different feeding system treatments: full-time grazing or part-time grazing combined with indoor feeding of fresh grass with low or high concentrate supplementation. Milk was sampled in spring, summer and autumn. Milk coagulation time was 15.0, 19.0 and 17.7 min, coagulation dynamics 1.67, 3.41 and 1.79 min, and curd firmness 52.7, 32.4 and 47.0 mm in spring, summer and autumn, respectively. Thus, milk coagulation properties of the milk were lower during summer. There were strong seasonal effects on milk FA proportions, but there were not always changes with progressing season, or changes were different with respect to the impact of the feeding systems (system × season interaction). The milk fat was favourably rich in oleic acid, conjugated linoleic acid and α-linolenic acid and had a low n -6/ n -3 fatty acid ratio in all systems. Factors like seasonal variations in grass composition and the energy balance of the cows were considered relevant for the milk FA composition. Overall, seasonal variations in milk quality were less pronounced with part-time grazing with fresh grass indoors as compared to full-time grazing without concentrate.
... In recent years, however, there has been increasing interest in health issues related to food consumption, in particular in terms of the fat content of foods. Milk and dairy products are an important source of dietary fats and contain unsaturated fatty acids that are beneficial to human health and that are influenced by the cow's diet (Elgersma 2015). ...
... Both pasture herbages (PRG and TFC) had a high content of linolenic acid with a mean of 60 g/100 g total fatty acids, which was lower in the triticale silage (TSL), and the concentrate (CONC) had a high proportion of linoleic acid, as has been reported in the literature (Elgersma 2015). The contents of linolenic, linoleic and palmitic acid in TSL were similar to reports by Khan et al. (2015) for common oat (Avena sativa) as the main fatty acids in forage. ...
Article
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Milk contains fatty acids (FA) beneficial to human health, so there is interest in the effect of feeding strategies on the FA content of milk. Small-scale dairy systems require conserved forages in the dry season. Cow diets of silages and concentrates yield a lower content of beneficial FA in milk. The objective was to determine the FA profile of feeds and milk from dairy cows on daytime grazing of pastures fed two levels of triticale silage and concentrate. Eight Holstein cows grazed pastures of perennial ryegrass or tall fescue. Triticale silage was offered at two levels (7.5 and 5.0 kg DM/d), in addition to 4.65 kg DM/d of concentrate. The experimental design was a 2 × 2 factorial with two pastures and two levels of silage in a repeated 4 × 4 Latin Square. Linolenic, linoleic, and palmitic acids comprised over 85% of FA in forages, and linoleic acid constituted 50% of FA in the concentrate. There were no differences in the milk composition, or the FA content of milk among treatments or periods (P>0.05). A higher inclusion of triticale silage did not change the fatty acid profile of milk. The content of beneficial FA in milk was similar to that of grazing cows.
... Namely, milk produced during pasture season generally should have lower content of dominant SFA and higher content of favourable MUFA and PUFA (Elgersma et al., 2015;Kay et al., 2004;Vanhatalo et al., 2007;Gómez-Cortés et al., 2009). Fatty acid milk profile of grazing organic dairy cows is characterised by higher content of PUFA and CLA (Chilliard et al., 2007;White et al., 2001;Elgersma, 2015) compared to housed conventional cows. ...
... Namely, milk produced during pasture season generally should have lower content of dominant SFA and higher content of favourable MUFA and PUFA (Elgersma et al., 2015;Kay et al., 2004;Vanhatalo et al., 2007;Gómez-Cortés et al., 2009). Fatty acid milk profile of grazing organic dairy cows is characterised by higher content of PUFA and CLA (Chilliard et al., 2007;White et al., 2001;Elgersma, 2015) compared to housed conventional cows. This is very important in human nutrition because CLA acts as an anticarcinogenic agent (Parodi, 1999). ...
Article
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The aim of this study was to determine effect of diet-based seasonal changes on fatty acid composition of Jersey milk in mountain region of Croatia. Bulk milk samples (200 mL) were collected during total-mixed ratio (TMR)-based, intermediate and pasture-based diet. Fatty acid composition of milk was determined by gas-chromatography. We found that pasture-based diet has positive effect on fatty acid composition of Jersey milk considering human nutrition. During pasture-based diet, Jersey cows produced milk with lower (P<0.05) saturated fatty acid and higher (P<0.05) polyunsaturated fatty acid content. Namely, regarding individual fatty acids, milk produced during pasture-based diet had lower (P<0.05) C16:0 and higher (P<0.05) C18:2n-6, C18:3n-6 and conjugated linoleic acid (CLA) content than milk produced during TMR and intermediate diet. Milk produced during pasture-based diet can be valuable source of healthbeneficial PUFA in diet.
... Perennial ryegrass (PR; Lolium perenne) is the pivotal pasture species in the pastoral grazed system in temperate regions such as New Zealand. Freshly grazed PR contains greater concentrations of polyunsaturated FA (Sun and Gibbs 2012;Rugoho et al. 2017), increasing the concentration of Omega-3 FA and conjugated linoleic acid (CLA; C18:2 c9, t11) in the milk when compared with silage-based or concentratebased diets (Elgersma 2015). Linoleic acid (LA; C18:2 c9, c12) and α-linolenic acid (ALA; C18:3 c9, c12, c15) in the herbage are the two main precursors of these beneficial FA in ruminant products (Lock and Bauman 2004). ...
... Several reviews (Jenkins et al. 2008;Elgersma 2015;Toral et al. 2018) postulated that that the concentration of desirable PUFA in the milk of ruminants could be influenced by the concentration of LA and ALA in the herbage. Increasing the concentration of PUFA in the diet of dairy cows can substantially improve both their concentration and that of CLA in ruminant-source foods (Elgersma et al. 2006). ...
Article
The effect of defoliation frequency and severity on FA and nutrient composition of forage chicory (Cichorium intybus L.) before and after vernalisation were compared. Before vernalisation, the FA and nutrient components exhibited little variation with defoliation frequency and severity irrespective of the time of day. After vernalisation, total FA more than halved compared with pre vernalisation levels (52.2 versus 19.2 mg/g DM). Concentrations of total FA and polyunsaturated FA: linoleic and linolenic declined by 63%, 50%, and 74%, respectively. Furthermore, extending the defoliation frequency from 300 to 600 growing degree-days after vernalisation caused a decline of 28% of linoleic, 40% of linolenic and 33% of total FA concentrations. Diurnal fluctuations were detected for linoleic and oleic acids after vernalisation (P < 0.01). In terms of nutrient composition, vernalisation decreased CP, digestibility and ME, while fibre contents increased. Between morning and afternoon, there were general declines in CP and fibre contents as well as increases in soluble sugars the herbage regardless of vernalisation. Overall, the feeding value and the concentration of FA were greater on chicory herbage managed under shorter regrowth intervals than that under longer regrowth intervals, which is likely to favour animal production and the concentration of the desirable FA in ruminant products.
... Although the EE intake of cows fed CBC was low (as a result of the reduction in supplement intake), it was observed an effect of CBC on milk FA profile. However, this effect was probably more related to the variation observed in herbage intake than directly due to CBC inclusion in the supplement (Lourenço et al., 2008;Elgersma, 2015). The highest herbage intake observed for treatments with greater inclusion of CBC may have been associated with a reduced SFA proportion in milk fat. ...
... It is well known that rumen biohydrogenation (BH) is largely affected by forage species (Elgersma, 2015;Jaakamo et al., 2019), diet composition Lourenço et al., 2008), and secondary metabolites such as phenolic compounds (tannins) (Khiaosa-ard et al., 2009;Cabiddu et al., 2010;Vasta et al., 2019). Experimental results have shown differing data on the effects of tannins on the concentration of BH intermediates and on the performance of the animal (Conte et al., 2017). ...
Article
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This study evaluated the effects of dietary inclusion of cracked babassu coconut (CBC) in the supplement on nutrient utilization, performance, and milk fatty acid (FA) composition of dairy cows grazing Megathyrsus maximus cv. Mombasa. Five multiparous Holstein × Zebu mid-lactation cows (125 ± 16.5 days in milk) were assigned to five dietary treatments (replacement of 0%, 20%, 40%, 60%, and 80% of ground corn with CBC, on a dry matter (DM) basis) in a 5 × 5 Latin square design. The intake of DM from the supplement, crude protein (CP), non-fiber carbohydrate (NFC), fat (ether extract (EE)), and total digestible nutrients (TDNs) decreased linearly (P < 0.05), while the intake of DM from forage increased linearly (P < 0.05), with the increase in CBC inclusion in the supplement. Conversely, total DM intake was unaffected (P > 0.05). The DM, NFC, EE, and TDN digestibility decreased linearly (P < 0.05), while organic matter (OM) digestibility decreased in a quadratic fashion (P < 0.05), as CBC inclusion in the supplement increased. Nevertheless, digestibility of CP was unaffected (P > 0.05). Milk yield and composition (lactose, fat, protein, casein, and majority of FA) showed a linearly decreasing pattern (P < 0.05) with the increasing of CBC inclusion. However, proportions of trans-vaccenic acid, rumenic acid, total monounsaturated FA, and odd- and branched-chain FAs increased linearly (P < 0.05). On the opposite, total saturated FA (SFA) and the n-6:n-3 FA ratio in milk fat decreased linearly (P < 0.01). Hence, replacement of corn meal with CBC up to 80% in the supplement decreases nutrient intake and digestibility, as well as milk yield response in grazing dairy cows. However, CBC inclusion may enhance the nutritional properties of milk fat.
... However, elephant grass has been scarcely investigated with respect to factors known to influence the forage FA profile. Aspects related to species/cultivar, age of regrowth, season of the year, nitrogen fertilization, temperature, light intensity and pasture management modulate the FA profiles of forages (Boufaïed et al., 2003;Dewhurst et al., 2006;Khan, Cone, Fievez, & Hendriks, 2012;Glasser, Doreau, Maxin, & Baumont, 2013;Elgersma, 2015;Khan et al., 2015). Knowledge of these factors could help to define management strategies to increase precursors for beneficial FAs in products of ruminants (Elgersma, 2015), especially α-linolenic acid, the main FA in forages and the most useful for enhancing milk fat quality (Glasser et al., 2013). ...
... Aspects related to species/cultivar, age of regrowth, season of the year, nitrogen fertilization, temperature, light intensity and pasture management modulate the FA profiles of forages (Boufaïed et al., 2003;Dewhurst et al., 2006;Khan, Cone, Fievez, & Hendriks, 2012;Glasser, Doreau, Maxin, & Baumont, 2013;Elgersma, 2015;Khan et al., 2015). Knowledge of these factors could help to define management strategies to increase precursors for beneficial FAs in products of ruminants (Elgersma, 2015), especially α-linolenic acid, the main FA in forages and the most useful for enhancing milk fat quality (Glasser et al., 2013). ...
Article
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This study aimed to evaluate the chemical composition and fatty acid (FA) profile of chopped forage and silage of BRS Capiaçu elephant grass at four regrowth ages: 50, 70, 90 and 110 days. A randomized block design with five replications was used. The ensiling was carried out manually in experimental silos without wilting using no additives or bacterial inoculants. The results were analyzed using mixed models (P < 0.05). The model included treatment (regrowth age) as a fixed effect and block as a random effect. Linear and quadratic effects of the treatments were analyzed using orthogonal contrasts. There were linear increases in the dry matter (DM, g kg-1) and lignin (g kg-1 DM) contents and linear reductions in the in vitro DM digestibility (g kg-1) of chopped grass and silage as a function of regrowth age (P < 0.001). Quadratic effects (P ≤ 0.01) were observed for the chopped grass contents (g kg-1 DM) of crude protein (CP), ether extract (EE) and neutral detergent fiber (NDF) as a function of regrowth age. There were linear decreases (P < 0.0001) in the CP content (g kg-1 DM) and pH and linear increases (P < 0.001) in the EE and NDF contents (g kg-1 DM) in the silage as a function of regrowth age. There were linear decreases (P < 0.01) in the chopped grass contents and linear increases (P < 0.05) in the silage contents of total FAs, linoleic and α-linolenic acids (g kg-1 DM) asa function of regrowth age. BRS Capiaçu elephant grass must be harvested at up to 70 days of regrowth to obtain forage with good nutritional value and the highest levels of linoleic and α-linolenic acids (g kg-1 DM). To produce silages with adequate pH values and the highest levels of linoleic and α-linolenic acids (g kg-1 DM), BRS Capiaçu must be harvested between 90 and 110 days of regrowth.
... Eicosapentaenoic acid and 7Z, 10Z, 13Z, 16Z, 19Z-docosapentaenoic acid are n-3 PUFA molecules, which have benefits in preventing cardiovascular disease and in being anti-inflammatory (28), and were found to have significantly increased in the present study, indicating that the nutritional value of milk was improved in the EUL group. In previous studies, it was found that the amount of fatty acid in feed determines the fatty acid profile in dairy products (29). EUL groups are rich in linolenic acid, which is the precursor of 7Z, 10Z, 13Z, 16Z, 19Z-docosapentaenoic acid and eicosapentaenoic acid, which explains the increase of 7Z, 10Z, 13Z, 16Z, 19Zdocosapentaenoic acid and eicosapentaenoic acid in milk. ...
Article
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Eucommia ulmoides leaves (EUL) contain a variety of natural bioactive compounds including chlorogenic acid, geniposide acid, and aucubin. These bioactive chemicals improve immune function and regulate lipid metabolism. The aim of this study was to investigate the effects of EUL on the biochemical properties of milk. Twenty Holstein dairy cows were randomly allocated to two groups fed a control (CTR, diet without EUL, n = 10) or EUL (diet containing 3% EUL, dry matter, n = 10) diet for 55 d. At the end of the experimental period (d 55), milk samples were collected and analyzed to determine their composition. Though levels of milk fat, protein, lactose, and total milk solids were similar between the groups, small molecules, metabolites, lipids, and cytokines differed. Compared with the CTR group, the EUL group had an improved cluster of differentiation (CD)4/CD8 ratio (P < 0.05) and lower interleukin (IL)-8 and IL-6 content (P < 0.05). Metabolomics analysis identified 14 metabolites including 7Z, 10Z, 13Z, 16Z, 19Z-docosapentaenoic acid (FC = 3.129), adrenic acid (FC = 2.830), and eicosapentaenoic acid (FC=1.685) as having significantly increased in the EUL group (P < 0.05) while 11 metabolites, including indole-2-carboxylic acid (FC = 0.636), cholic acid (FC = 0.430), and creatine (FC = 0.784) had significantly decreased (P < 0.05). Based on a constructed metabolome map, linoleic acid metabolism had the highest impact value for EUL. A total of 21 lipid classes and 1,094 lipid species were detected in the milk by lipidomic analysis, among which 40 differed significantly between the CTR and EUL groups. The present findings showed that the EUL altered milk composition. Correlation analysis showed that 7Z, 10Z, 13Z, 16Z, 19Z-docosapentaenoic acid, adrenic acid, and eicosapentaenoic acid levels were negatively correlated with those of the inflammatory factors IL-6 and IL-8 (P < 0.05), indicating that EUL improved milk quality by reducing inflammatory factors and increasing the CD4/CD8 ratio. Overall, our data demonstrate that EUL had positive effects on milk antioxidant parameters, immune indices, and micro-composition metabolism, thereby improving milk quality.
... O enriquecimento da dieta de ruminantes com os ácidos graxos C18:2 n-6 e C18:3 n-3 normalmente se dá por meio da inclusão de grãos de oleaginosas (ex.: grão de soja, semente de linhaça) ou de óleos vegetais puros (Mourthé et al., 2015;Lopes et al., 2019). Outra forma eficaz e de menor custo para aumentar o consumo destes ácidos graxos pelos animais é a ingestão de forragens frescas de boa qualidade nutricional, seja por meio do pastejo ou via fornecimento de capim picado no cocho, como no caso do uso de capineiras (Elgersma, 2015). Além disso, estudo recente conduzido pelo nosso grupo de pesquisa (Gama et al. -no prelo) mostrou que a inclusão de palma forrageira (cultivar orelha de elefante mexicana) em dieta à base de silagem de sorgo suplementada com óleo de soja aumentou expressivamente os teores dos ácidos vacênico, rumênico e linoleico na gordura do leite de vacas sendo, portanto, uma nova e promissora estratégia nutricional para aumentar o valor potencialmente funcional do leite. ...
Technical Report
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A palma forrageira constitui importante recurso forrageiro para a produção animal no semiárido brasileiro. Além do elevado valor energético quando comparada a outras forragens, a palma supre boa parte das exigências de água dos animais. Resultados recentes do nosso grupo de pesquisa mostraram que a inclusão de palma orelha de elefante mexicana em uma dieta suplementada com óleo vegetal alterou positivamente os ácidos graxos do leite de vacas leiteiras, indicando uma nova e promissora aplicação para essa cultura. Algumas cultivares de palma forrageira utilizadas no Nordeste foram avaliadas quanto à composição química, perfil de ácidos graxos, teores de açúcares e de fibra alimentar, o que permitiu uma estimativa dos teores de amido e de pectina, e sua comparação com outros alimentos e coprodutos normalmente fornecidos para ruminantes. As variedades de palma forrageira apresentaram teores (base seca) de fibra alimentar de 35 a 43%, açúcares totais de 8,5 a 15,6%, enquanto os teores estimados de amido variaram de 28,0 a 40,5%. Foram observados elevados teores de ácido α-linolênico de até 34% na cultivar orelha de elefante mexicana. Os resultados deste trabalho mostram a natureza química peculiar da palma forrageira e seu grande potencial para inclusão na alimentação de ruminantes.
... Therefore, there is an interest in feeding strategies for dairy cows that may increase the concentration of these compounds in milk (Elgersma et al., 2006;Elgersma 2015;Saroj et al., 2017;Vieyra-Alberto et al., 2017;Plata-Reyes et al., 2018). ...
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Diets have an important effect on the fatty acid (FA) content in milk from dairy cows so that feeding strategies may modify the FA profile. There is little information on the fatty acid contents of whole-crop barley (BLY) and black oat (BKO) silages and on milk from cows fed these silages that are an alternative forage for small-scale dairy systems (SSDS). Given the growing interest in foods with favourable health attributes, the objective was to identify the FA content of milk from dairy cows fed whole-crop BLY and BKO silages in small-scale systems. Three inclusion levels of BLY and BKO silage were assessed in nine lactating cows at pasture for 8 h/day and supplemented with 4.6 kg/DM/cow/day commercial concentrate. Treatments were BLY: 10 kg DM/cow/day BLY silage; BKO: 10 kg DM/cow/d BKO silage; and BLY/BKO: 5 kg BLY and 5 kg DM/cow/d BKO silages (50:50). A 3 × 3 Latin square design repeated three times with nine cows and 14-day periods was utilised. Variables evaluated were the content of fatty acids present in feeds and milk. Contents of linoleic (C18:2n-6) and linolenic (C18:3n-3) acids, as precursors of polyunsaturated fatty acids, were 46 in BLY and 50 BKO g/100 g, lower than for multispecies pasture (61 g/100 g). There were statistical differences in the content of short-chain fatty acids in milk (P < 0.05), being lower for BLY (18.9 g/100 g) compared with BKO (20.4 g/100 g) and BLY/BKO (20.6 g/100 g), the saturated fatty acids and linoleic acid (C18:2n-6c) were higher in BLY/BKO in relation to BLY and BKO. Content of health-promoting polyunsaturated fatty acids in milk was higher in BLY/BKO (P < 0.05). There were no differences (P < 0.05) in the atherogenic index, with values within reports. Small-grain cereal forages may produce milk with a favourable fatty acid content for human health.
... The appearance of PUFALC C22: 6 n-3 which had high values observed in pasture lambs compared to those in concentrate, was due according to (Díaz et al., 2011) to the elongation and desaturation of C18: 3 n-3. Feeding practices in free ranges advantageously improve the FA profile; on the other hand, the variability of the individual plants that characterize and dominate in these different rangelands can affect the capacity and retention time of FA in the rumen, thus their composition in antioxidants which protect PUFAs, lead to a considerable accumulation of these FAs, in particular, C18: 3n3, the precursor of C22: 6n3 (Elgersma, 2015). Recent simultaneous studies have described lipogenesis in the rumen, as a function of biohydrogenation, which is conditioned by the selection of ruminal microflora depending on the type of food, the variety of plant species, the amount of fiber and starch consumed by the ruminant which can decrease ruminal pH, which inhibits the activity of certain bacteria and ...
Article
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This work aimed to assess the impact of a diet based on green pastures of steppe rangelands and another based on a concentrate diet, on the composition of the intramuscular lipid fraction of different sections of the biceps femoral muscle of lambs, in two regions of the wilaya of Tiaret, in winter and in spring. The biceps femoral muscle sample collection came from 20 different lamb carcasses (10 samples for each of our two study regions, with 05 samples for each season). These samples were taken on different occasions in large butcher shops. Total SFA content in both regions shows dominance in lambs from the regimen concentrate, that C 16: 0 and C 18: 0 are the most dominant. There is no remarkable difference in total MUFA content, and on individual monounsaturated FA, between the two regimens. In both regions, the most dominant FAs in the intramuscular lipid fraction of pasture lambs are C18: 3n3 followed by C18: 2n6 cis-9, C20: 4n6, C20: 5n3, and C22: 6n3, compared to those from concentrate regimen; however, lambs from Chehaima concentrate regimen had the most dominant FA in their intramuscular fat, C18: 3n6 followed by C20: 4n6, compared to those from pastures of Naima. The values of the ratio n-6 / n-3 correspond to the nutritional recommendations. The feed ratio ΣPUFA / ΣSFA of lambs from pastures in the Chehaima region is the only one that corresponds to the desired value. Based on this research, it is concluded that lambs that have grazed grass in steppe rangelands have the richest meat in omega 3, which is more desirable and benefits for human health.
... There are also human health benefits to be derived from consuming products from animals raised on grass. In particular, milk from pasture-fed cows (grass or clover) has significantly higher concentrations of healthy fatty acids (Elgersma, 2015). These differences are reflected in the products produced from milk from pasture-fed cows. ...
Article
Grassland-based dairy production provides multiple benefits to farmers and to the wider society, but the European grassland area has been significantly reduced during the last decades. This paper aims to explore societal and economic options to support grassland-based dairy production in Europe. In the recent past, several societal initiatives have emerged to stimulate grassland-based dairy production: treaties, premiums and market concepts. When developing stimulating initiatives, the mindset of the farmer should be taken into account. Farmers are key actors when it comes to maintaining and improving grassland-based dairy production systems since they decide on the day-to-day management of the farm. To maintain grassland-based dairy production and to preserve the associated ecosystem services, it is, therefore, necessary to clearly show the importance of this production system for society to the farmers (show the customer perspective) and to support this by valuing the products from these systems accordingly. “New” business models should financially reward farmers for their added value contributions in delivering ecosystem services.
... The first may rely on different genetic backgrounds, due to the specific breeds involved in the present experiment and those considered in previous studies. The second is likely due to different feeding regimes, with particular regard to the fresh herbage grazed by cows enrolled in the present study, which is known to reduce SFA in favour of unsaturated FA [22,23]. Results from the analysis of variance for the concentration of milk FA are summarized in Table 3. ...
Article
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The change in feeding regime of dairy herds using summer grazing in mountainous areas has several implications on cows' productivity and milk composition. The present study quantified the effect of summer grazing on the milk fatty acids (FA) profile of Simmental and crossbred cows in an alpine holding. A total of 616 milk samples of 71 cows were collected 3 days before the onset of the grazing season until 91 days of grazing. Individual and groups of FA were quantified through mid-infrared spectroscopy. Data were analysed using a linear mixed model including the fixed effects of breed, stage of lactation, parity, sampling period, and the random effects of cows nested within breed and the residual. The stage of lactation and the sampling period were the most significant factors associated with milk FA. The variance explained by the random cow effect ranged from 15.10% (C18:1) to 25.31% (medium-chain FA). The concentration of C14:0, C16:0, and short-and medium-chain FA decreased across the summer season. Long-chain FA and polyunsaturated FA concentrations were greater in milk obtained at pasture compared with milk obtained indoors. Given these outcomes, the present study demonstrated the positive effect of grazing on milk FA composition from a nutraceutical point of view.
... Both FRAP and thiol groups have been used in previous studies as reliable indicators of overall antioxidant status in dairy cows (Bernabucci et al., 2002;Haubold et al., 2020). The elevated levels of α-tocopherol, β-carotene, and retinol can primarily be attributed to the pasture composition, since birds foot trefoil, plantain, and chicory contain similarly high amounts of α-tocopherol and β-carotene in comparison with the traditional Grass-clover pastures (Elgersma, 2015). However, the increased abundance of birds foot trefoil and red clover (at least 72%) in the Legume pastures compared with the abundance of plantain and chicory in the Forb pastures (up to 56%) likely explains why the Legume pastures had higher concentrations of β-carotene than the Forb pastures. ...
Article
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Some pasture species are rich in phytochemicals, able to improve milk yield and quality and to reduce the environmental impacts of livestock farming. The phytochemicals interact with the different gene networks within the animal, such as nuclear factor erythroid 2-related factor 2 (NRF2), but their overall impact on animal health remains to be fully understood. The objective of this study was to identify the effects of pasture Legumes and non-leguminous Forbs containing high bioactive compounds on metabolism and activity of the liver, antioxidant response, kidney function, and inflammation of dairy cows using a large array of blood parameters associated with metabolism and the innate immune system. For this purpose, 26 parameters and the concentration of certain bioactive compounds were assessed in blood plasma, collected from the Jersey cows grazing either Grass, Legume, or Forb-based pastures. In addition, serum collected from all the cows was utilized to detect the changes in NRF2 activation in bovine mammary alveolar cells (MACT) and hepatocytes. Compared with Grass, the cows that grazed both Forb and Legume pastures had lower β-hydroxybutyric acid (BHB) and creatinine and larger vitamin E and the ferric reducing ability of the plasma, supporting an improved antioxidative status for these animals. Compared with both Grass and Legume, the cows that graze Forb pasture had lower urea and urea to creatinine ratio, and lower creatinine, indicating a better kidney function. The cows grazing Legume pasture had greater hematocrit, bilirubin, cholesterol, albumin, β-carotene, retinol, and thiol groups but lower ceruloplasmin, paraoxonase, and myeloperoxidase (MPO) than those grazed Grass and Forb pastures, indicating a positive effect of Legume pasture on the liver, oxidative stress, and red blood cells. The plasma of cows in the various pastures was enriched with various isoflavonoids, especially the cows grazed on Forb and Legume pastures, which likely contributed to improving the antioxidative status of those cows. However, this effect was likely not due to the higher activation of NRF2. Overall, these results indicate that Forb and Legume pastures rich in secondary metabolites do not strongly affect the metabolism but can improve the status of the liver and the kidney and improve the efficiency of N utilization and antioxidant response, compared with the Grass pasture.
... The significance of meat as a source of protein can certainly be achieved with an average meat intake of 85-100 g⋅day − 1 . The NND typically includes meat from free-range livestock and game due to their nutritional and sustainability advantages (Costa et al., 2016;Elgersma, 2015;Mithril et al., 2013). In addition, beef contributes with a significant percentage (19%) to the total meat consumption in Galicia (MAPA, 2019). ...
Article
The partnership for sustainable and healthy food is a challenge shared by governments, food industry, environmental science, and the health service. At the European level, the application of policies based on the Mediterranean-style eating pattern is recommended. In this regard, attention is being paid to the New Nordic Diet (NND), which shares many similarities with the Mediterranean one but comprises typical foods from Nordic countries. Therefore, it could be transferred to anywhere in the world, including Spain, where it would coexist with the recommendations of the Mediterranean Diet (MD) and the southern European Atlantic Diet (SEAD). The main objective of this study is to propose the modelling of the health, economic, environmental and nutritional indicators of the southern version of NND (SNND) and to compare, when possible, the results with those of the alternatives. The environmental metrics for NND, carbon footprint (CF) and water footprint (WF), were estimated at 3.98 kg CO2·person⁻¹·day⁻¹ and 3528 l respectively, a slightly worse environmental profile than for MD, but better than for SEAD. In relation to economic metrics, the updated cost index to 2019 was 4.30 €·person⁻¹·day⁻¹, similar to MD and lower than for SEAD. The overall dietary quality score was 126, a higher result than the baseline (100), but worse than those identified for SEAD and MD. In terms of health outcomes, NND showed benefits that reduce non-communicable diseases such as the risks of type 2 diabetes mellitus (T2D) by 31%, colorectal cancer (CRCA) by 35% and cardiovascular disease (CVD) by 7%. Compliance with the NND was also associated with a weight loss of 1.83 kg per person following the diet. Epidemiological evidence supported greater weight loss when following the NND, but greater reductions in the CVD risk when adhering to MD. The dissemination through educational campaigns of these recommended dietary patterns and the incorporation in the dietary guidelines of simple indicators of nutritional quality, environmental impacts and health, easily understood by a wide audience, is one of the most important challenges of public and environmental health.
... The FA composition of cows' milk became less favourable to human health in the last decades due to changes in feeding and management practices with notably higher proportions of concentrates and silages in diets and less grazing (Elgersma et al. 2006). When compared with the total mixed ration (TMR) fed, grazing dairy cows produced milk fat with higher concentrations of monounsaturated FAs (MUFAs), OA and vaccenic acid (VA), PUFAs and conjugated linoleic acids (CLA), and lower concentrations of hypercholesterolaemic FAs (12:0, 14:0, and 16:0) (Chilliard et al. 2007;Elgersma 2015). ...
Article
The aim of the study was to estimate the effect of rapeseed pomace and extruded full-fat soya in the diets of dairy cows on changes in the milk fatty acid (FA) profile. The experiment was carried out on 30 dairy cows and divided into two periods: the indoor feeding period and the grazing period. Control diet cows were fed the farm’s total mixed ration (TMR); cows of experimental group 1 (ES) cows were fed the farm’s TMR supplemented with extruded full-fat soya; cows of experimental group 2 (RP) were fed the farm’s TMR supplemented with rapeseed pomace. The total content of saturated fatty acids (SFAs) tended to be lower in the RP and ES groups than in the control group during both feeding periods. Our results suggest that supplementing diets with rapeseed and soybean products are both effective in improving the fatty acid proportion of desirable (hypocholesterolaemic) FAs, mainly oleic acid (18:1n-9), linoleic acid (18:2n-6) and conjugated linoleic acid (CLAcis9trans11). The study showed that during the indoor feeding period, the unsaturated fatty acid (UFA) contents were significantly higher in the ES group compared to the control group ( P < 0.05). The nutritional value of milk from the feeding groups in which rations were supplemented with ES or RP was better due to a quartile reduction of the atherogenicity index (AI) and the significantly increased spreadability index (SI) of the butter manufactured during the indoor feeding period ( P < 0.01).
... Indeed, dairy diets based on fresh grass have led to significantly higher concentrations in VA, CLA9 and total CLA 40 . Many studies report that forage from permanent meadows produces milk with more CLA and n-3 than from maize or other cereal silage diets [41][42][43] , as in our survey. These elevated concentrations of CLA are likely to be due to polyphitic forage, rich in LA and ALA, which undergo incomplete hydrogenation, generating the intermediate VA rather SA (C18:0). ...
Article
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Although there are many studies on the importance of fatty acids (FA) in our diet and on the influence of dairy diets on FA metabolism, only a few investigate their predictive capacity to discriminate the type, amount and conservation method of farm forages. This research quantifies differences in milk FA concentrations and, using a supervised factorial discriminant analysis, assesses potential biomarkers when replacing maize with other silages, grass/lucerne hays or fresh grass. The statistical modelling identified three main clusters of milk FA profiles associated with silages, hays and fresh grass as dominant roughages. The main implication of a dairy cow feeding system based on poliphytic forages from permanent meadows is enhancing milk’s nutritional quality due to an increase in beneficial omega-3 polyunsaturated FA, conjugated linoleic acids and odd chain FA, compared to feeding maize silage. The study also identified a small but powerful and reliable pool of milk FA that can act as biomarkers to authenticate feeding systems: C16:1 c-9, C17:0, C18:0, C18:3 c-9, c-12, c-15, C18:1 c-9, C18:1 t-11 and C20:0.
... Animal nutrition has a major influence on the fatty acid profile of raw milk when ruminants have direct access to pasture, as is our case, increasing the presence of polyunsaturated fatty acids [51]. Cheese made from the milk of these cows is preferred by consumers [52]. ...
Article
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The evolution during ripening on the quality of Apuseni cheese was studied in this research. The cheese samples were controlled and evaluated periodically (at 4 months) during 16 months of storage (at 2–8 °C) for physicochemical parameters (pH, moisture, fat, fat in dry matter, total protein, ash, NaCl), microbiological (total combined yeasts and molds count (TYMC), total viable count (TVC), Escherichia coli, Staphylococcusaureus, Salmonella, lactic acid bacteria (LAB)), fatty acids (FA) and volatile compounds. For better control of the quality of the cheese, the storage space was evaluated for TYMC and TVC. The ripening period showed improved effects on the quality of the cheese, showing lower values for moisture and pH and an increase in macronutrients. Both the cheese samples and the storage space were kept within the allowed microbiological limits. Lipids are predominant, the predominant FAs being saturated fatty acids (SFAs), which decrease, while monounsaturated fatty acids (MUFAs) increase. During ripening, the microbiological and chemical changes result in the development of flavor. Major volatile compounds such as 2-heptanone show accumulations, while acetophenone, limonene, or thymol show a decrease. In conclusion, Apuseni ripening cheese clearly involves a complex series of transformations, leading to a ripening cheese with improved nutritional and aromatic characteristics.
... Grazed pasturelands play multiple roles in agroecosystems that can benefit the sustainability of ruminant-based agriculture. This includes lower feeding costs [1], higher animal welfare and lower occurrence of lameness and mastitis, and increased milk quality compared to indoor feeding [2]. However, despite these advantages, Walloon intensive dairy farmers increasingly turn away from grazing. ...
Article
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Accurate information about the available standing biomass on pastures is critical for the adequate management of grazing and its promotion to farmers. In this paper, machine learning models are developed to predict available biomass expressed as compressed sward height (CSH) from readily accessible meteorological, optical (Sentinel-2) and radar satellite data (Sentinel-1). This study assumed that combining heterogeneous data sources, data transformations and machine learning methods would improve the robustness and the accuracy of the developed models. A total of 72,795 records of CSH with a spatial positioning, collected in 2018 and 2019, were used and aggregated according to a pixel-like pattern. The resulting dataset was split into a training one with 11,625 pixellated records and an independent validation one with 4952 pixellated records. The models were trained with a 19-fold cross-validation. A wide range of performances was observed (with mean root mean square error (RMSE) of cross-validation ranging from 22.84 mm of CSH to infinite-like values), and the four best-performing models were a cubist, a glmnet, a neural network and a random forest. These models had an RMSE of independent validation lower than 20 mm of CSH at the pixel-level. To simulate the behavior of the model in a decision support system, performances at the paddock level were also studied. These were computed according to two scenarios: either the predictions were made at a sub-parcel level and then aggregated, or the data were aggregated at the parcel level and the predictions were made for these aggregated data. The results obtained in this study were more accurate than those found in the literature concerning pasture budgeting and grassland biomass evaluation. The training of the 124 models resulting from the described framework was part of the realization of a decision support system to help farmers in their daily decision making.
... Among them, we can list the n-6/n-3 ratio that, in dairy products, essentially reflects the concentrations of linoleic (n-6) and a-linolenic (n-3) acids. This index can be improved by increasing the consumption of fresh grass in ruminants diets, resulting much better in mountain products (Leiber et al. 2005;Elgersma 2015). The n-6/n-3 ratio has already showed to reach values more than two times higher in conventional milk compared to extensive or pasture-based milk (Davis et al. 2020). ...
Article
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Mountain dairy products are recognised as high-quality food but there are still few studies concerning the effects of seasonality and herd management on the profile of bioactive compounds in cheeses. This study was planned to assess the effect of season (summer versus winter) and feeding management (pasture versus integration) on fatty acids (FAs) profile, anti-hypertensive (ACE-IA) and anti-oxidant properties (ABTS-SA, FRAP), total thiol (SH) and phenolic (TP) contents of cheeses from two dairy cow farms (Farm A and Farm B) located in Piedmontese Alps (Italy). Cheese samples collected in the farms were submitted to an integrated analytical approach and the results were processed by full factorial ANOVA and PCA. The trends observed from the FAs profile confirmed the beneficial influence of supplying fresh forage to lactating cows. The ACE-IA was higher in summer than in winter cheese but depended upon the farm factor. Among the indicators of antioxidant activity, only the ABTS-SA was affected by the season, even though with significant differences between the farms. The TP content did not show any clear pattern, but it was higher than the values described in the literature. The PCA of all the data showed that several FAs and the ABTS-SA gave relevant contributions to clearly group the cheese samples according to the production season or farm. In conclusion, alpine cheese exhibited high nutritional quality under the consumers’ health standpoint, and the identification of the healthier summer cheeses for traceability or labelling purposes, can be obtained. • Highlights • Seasonality and herd management practices affected the nutritional quality of cheese produced in two dairy farms in Piedemontese Alps. • Lipid quality was affected by the feeding strategy, with the greater improvements obtained by pasture grazing or fresh grass consumption in the barn. • ACE-inhibitory activity and anti-oxidant properties were influenced by both seasonality and farm of origin, with the best values measured in summer cheese.
... In the goats, SFA and MUFA decreased and PUFA increased. Though not significant, the goat trend follows what Elgersma (2015) described of dairy cows eating higher portions of grass where grass decreased SFA and increased PUFA. This was also substantiated by Couvreur et al. (2006) and Rego et al. (2016). ...
... Despite some studies reporting effects of dietary alterations on vitamin concentrations in milk (Adler et al., 2013;Poulsen et al., 2015), knowledge on dietary changes in pure grass-based diets with and without concentrates is still limited. Moreover, feeding fresh grass rather than silage has shown to affect milk fatty acid (FA) composition and the proportion of, for example, PUFA, increases (Elgersma, 2015). The concept of grass milk (i.e., nearly 100% forage-based diet) has further shown to reduce the n -6: n -3 FA ratio in milk (Benbrook et al., 2018), thereby improving the nutritive value of milk for human nutrition. ...
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... On the one hand, ruminants produce methane (CH 4 ) as a natural byproduct of microbial fermentation of feed in the rumen, contributing approximately 6% of the global anthropogenic GHG emissions (40% of all livestock emissions; Gerber et al., 2013;Beauchemin et al., 2020). On the other hand, grazed pastures which are the basis of those systems, when properly managed, potentially improve the sustainability of livestock production (Lobato et al., 2014;Elgersma, 2015;French et al., 2015), provide many social and environmental services (Werling et al., 2014;Mottet et al., 2017;Horrocks et al., 2019;Zubieta et al., 2020), and improve soil health indicators in tropical systems (Teutscherová et al., 2021). Hence, current grazing systems are being redesigned to link animal production with environmental management (Boval and Dixon, 2012;Carvalho, 2013) in light of current demands for sustainable agricultural production around the world (Herrero et al., 2010;Mottet et al., 2017). ...
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