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Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agro-food and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/#tabs|Name:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.

Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agro-food and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/#tabs|Name:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.

Carotenoids are isoprenoids widely distributed in foods that have been always part of the diet of humans. Unlike the other so-called food bioactives, some carotenoids can be converted into retinoids exhibiting vitamin A activity, which is essential for humans. Furthermore, they are much more versatile as they are relevant in foods not only as sources of vitamin A, but also as natural pigments, antioxidants, and health-promoting compounds. Lately, they are also attracting interest in the context of nutricosmetics, as they have been shown to provide cosmetic benefits when ingested in appropriate amounts. In this work, resulting from the collaborative work of participants of the COST Action European network to advance carotenoid research and applications in agro-food and health (EUROCAROTEN, www.eurocaroten.eu, https://www.cost.eu/actions/CA15136/#tabs|Name:overview) research on carotenoids in foods and feeds is thoroughly reviewed covering aspects such as analysis, carotenoid food sources, carotenoid databases, effect of processing and storage conditions, new trends in carotenoid extraction, daily intakes, use as human, and feed additives are addressed. Furthermore, classical and recent patents regarding the obtaining and formulation of carotenoids for several purposes are pinpointed and briefly discussed. Lastly, emerging research lines as well as research needs are highlighted.

Grasslands provide an important part of the feed used by domestic and wild ruminants. Fresh herbage is an important natural source of vitamins in ruminant diets. Concentrations of vitamins in plants depend on factors such as regrowth stage, temperature and day length, N fertilisation and leaf proportion in the harvested herbage. Most studies on vitamin concentrations in forages have been carried out with agronomical important grass species such as perennial ryegrass and legume species such as white clover, but hardly with other grassland forage species. As data of dicotyledonous species grown in a sward are scarce, yield, quality and vitamin contents in a number of herb (hereafter referred to as forb) and legume species were compared to a grass-clover mixture to get an insight into species differences.

A coordinated continental‐scale field experiment across 31 sites was used to compare the biomass yield of monocultures and four species mixtures associated with intensively managed agricultural grassland systems. To increase complementarity in resource use, each of the four species in the experimental design represented a distinct functional type derived from two levels of each of two functional traits, nitrogen acquisition (N2‐fixing legume or nonfixing grass) crossed with temporal development (fast‐establishing or temporally persistent). Relative abundances of the four functional types in mixtures were systematically varied at sowing to vary the evenness of the same four species in mixture communities at each site and sown at two levels of seed density. Across multiple years, the total yield (including weed biomass) of the mixtures exceeded that of the average monoculture in >97% of comparisons. It also exceeded that of the best monoculture (transgressive overyielding) in about 60% of sites, with a mean yield ratio of mixture to best‐performing monoculture of 1·07 across all sites. Analyses based on yield of sown species only (excluding weed biomass) demonstrated considerably greater transgressive overyielding (significant at about 70% of sites, ratio of mixture to best‐performing monoculture = 1·18). Mixtures maintained a resistance to weed invasion over at least 3 years. In mixtures, median values indicate <4% of weed biomass in total yield, whereas the median percentage of weeds in monocultures increased from 15% in year 1 to 32% in year 3. Within each year, there was a highly significant relationship (P < 0·0001) between sward evenness and the diversity effect (excess of mixture performance over that predicted from the monoculture performances of component species). At lower evenness values, increases in community evenness resulted in an increased diversity effect, but the diversity effect was not significantly different from the maximum diversity effect acros

1. Ecological and agronomic research suggests that increased crop diversity in speciespoor intensive systems may improve their provision of ecosystem services. Such general predictions can have critical importance for worldwide food production and agricultural practice but are largely untested at higher levels of diversity. 2. We propose new methodology for the design and analysis of experiments to quantify diversity-function relationships. Our methodology can quantify the relative strength of inter-specific interactions that contribute to a functional response, and can disentangle the separate contributions of species richness and relative abundance. 3. Applying our methodology to data from a common experiment at 28 European sites, we show that the above-ground biomass of four-species mixtures (two legumes and two grasses) in intensive grassland systems was consistently greater than that expected from monoculture performance, even at high productivity levels. The magnitude of this effect generally resulted in transgressive overyielding. 4. A combined analysis of first-year results across sites showed that the additional performance of mixtures was driven by the number and strength of pairwise inter-specific interactions and the evenness of the community. In general, all pairwise interactions contributed equally to the additional performance of mixtures; the grass-grass and legume-legume interactions were as strong as those between grasses and legumes. 5. The combined analysis across geographical and temporal scales in our study provides a generality of interpretation of our results that would not have been possible from individual site analyses or experimentation at a single site. 6. Our four-species agricultural grassland communities have proved a simple yet relevant model system for experimentation and development of methodology in diversity-function research. Our study establishes that principles derived from biodiversity research in extensive, semi-natural gras

Keywords: perennial ryegrass, dairy cows, intake, digestibility milk production, nitrogen utilisation.In the Netherlands, grass is one of the main roughages in the diet of high productive dairy cows. Grass is associated with two main problems: the limited dry matter intake (DMI) and the low N utilisation by dairy cows. Grassland is renovated every 3- 15 years and is usually resown with a mixture of mainly perennial ryegrass cultivars. The aim of the research described in this thesis was to evaluate the effects of perennial ryegrass cultivars on 1) degradation of herbage in the rumen of dairy cows, 2) the DMI, digestibility and milk production by dairy cows, and 3) the N utilisation by dairy cows. These effects were then related to sward characteristics and chemical composition of these cultivars, in order to identify new selection criteria that may be used in grass breeding programmes. Therefore, the effects of eight cultivars in a stall feeding experiment and four cultivars in a grazing experiment on intake, grazing behaviour, digestibility, milk production, milk composition and N utilisation were determined. The perennial ryegrass cultivars consistently differed in their water soluble carbohydrate (WSC) content. Among cultivars, the largest differences were found in WSC content, whereas the differences in crude protein and neutral detergent fibre content were small. An increased WSC content was expected to increase the palatability, and this may increase the intake. However, there was no effect of cultivar on intake in three of the four years of experiments. In one year, the lower intake of two cultivars was associated with a lower WSC content, but also with a severe crown rust infestation. However, the grazing behaviour did not differ among cultivars. The milk production and milk composition were almost not affected by cultivar, with the exception of the year with differences in intake. The cultivars differed only slightly in the degradation characteristics in th

Keywords:Perennial ryegrass, Lolium perenne , sward morphology, sward cutting, n-alkanes, herbage intake, selection, preference.Perennial ryegrass ( Lolium perenne L.) is the most important species for feeding dairy cows. The majority of the farmers in the Netherlands graze their dairy cows during summer. During grazing, the limited herbage intake is the main limitation of the dairy cows' production. This study examined opportunities for grass breeders to influence the quality of perennial ryegrass cultivars to improve the herbage intake of dairy cows.Six cultivars of perennial ryegrass (Abergold, Respect, Agri, Herbie, Barezane,Barnhem) were intensively studied during two years (2000 and 2001) between June and September. There were differences between the cultivars for important characteristics influencing herbage intake, e.g. herbage yield, sward surface height and density. Furthermore, differences between cultivars were found for the proportions and the biomass of leaf, stem and pseudostem in the sward. The sward cutting and the n-alkanes technique, both methods to determine the herbage intake by grazing dairy cows, were compared with an average that was calculated from the milk production and the live weight of the dairy cows. The sward cutting technique gave very variable results that varied largely per cow and year, and did not match with the expected calculated intake. The n-alkanes method gave less variable results that were more related to the expected calculated intake values. Within the n-alkanes method, the ratio C 32 :C 33 gave the best results.The effects of perennial ryegrass cultivars on the intake of grazing dairy cows were examined. In 2002 and 2003, cows grazed each of the four cultivars during four 2-week periods. Herbage intake was estimated using the C 32 :C 33 -alkanes method. In 2002, a clear difference was found between the cultivars, but in the second year no differences were found. A higher herbage intake was related with a higher mass of

Keywords: Dairy cows, Perennial ryegrass, Rumen fill, Clearance, Degradation, Grazing behaviour.In temperate environments, perennial ryegrass is the most widely used species for feeding dairy cows. That is because of its high productivity, palatability, digestibility and nutritive value. However, perennial ryegrass suffers from two main disadvantages: firstly, its unbalanced nutrient content in terms of crude protein (CP) and energy availability at rumen level and secondly, its low dry matter intake (DMI) by high producing dairy cows. In ruminant animals, DMI is a function of the balance between eating motivation, which is strongly related to palatability, on one hand and rumen capacity on the other. This thesis was divided into three parts: the first part aimed to investigate the possibility of improving pasture DMI by increasing rumen capacity. Rumen capacity is related to the rate of clearance (Kcl) of material from the rumen, which is the summation of both rates of degradation (kd) and passage (kp). Six varieties of perennial ryegrass were screened for their clearance and degradation rates using in vitro , in vivo and in situ techniques. The results suggested that there is a narrow range for selection with respect to clearance and degradation rate. The second part of this thesis aimed at investigating the possibility of improving pasture DMI by improving its palatability. Palatability is mainly a function of flavour and taste, which arise from certain compounds in the grass, especially water-soluble carbohydrates (WSC). High sugar grass varieties were fed to dairy cows in mid lactation. The results showed that feeding high sugar grass did not lead to an improved DMI and milk yield under both stall-feeding and grazing conditions. Moreover, milk composition in terms of fat, protein and lactose, rumen pH, fibre clearance and degradation rates were not influenced. However, rumen ammonia and milk urea concentrations were significantly reduced when feeding high sugar