251 research outputs found

    Comparative nutrient profiling of retail goat and cow milk

    Get PDF
    Goat milk is globally consumed but nutritional profiling at retail level is scarce. This study compared the nutrient composition of retail cow and goat milk (basic solids, fatty acids, minerals, and phytoestrogens) throughout the year and quantified the potential implications on the consumers’ nutrient intakes. When compared to cow milk, goat milk demonstrated nutritionally desirable traits, such as lower concentrations of C12:0, C14:0, C16:0 and Na:K ratio, and the higher concentrations of cis PUFA, EPA, DHA, isoflavones, B, Cu, Mg, Mn, P and I; although the latter may be less desirable in cases of high milk intakes. However, in contrast with nutritional targets, it had lower concentrations of omega-3 PUFA, vaccenic acid, lignans, Ca, S and Zn. The extent of these differences was strongly influenced by season and may demonstrate a combination of differences on intrinsic species metabolism, and farm breeding/husbandry practices

    Effect of production system and geographic location on milk quality parameters

    Get PDF
    A main reason for the rapid increase in organic food consumption is the perception that organic foods have a superior nutritional composition and/or convey health benefits. However, there is currently limited scientific knowledge about the effect of production systems on food composition. The study reported here compared fatty acid profiles and levels of fat soluble antioxidants in milk from organic and conventional production systems in 5 geographic regions in Europe (Wales, England, Denmark, Sweden and Italy). Levels of nutritionally desirable mono- and poly-unsaturated fatty acids (vaccenic acid, CLA, α-linolenic acid) and/or a range of fat soluble antioxidants were found to be significantly higher in organic milk

    Effects of concentrate crude protein content on nutrient digestibility, energy utilization, and methane emissions in lactating dairy cows fed fresh-cut perennial grass

    Get PDF
    Although many studies have investigated mitigation strategies for methane (CH4) output from dairy cows fed a wide variety of diets, research on effects of concentrate crude protein (CP) content on CH4 emissions from dairy cows offered fresh grass is limited. The present study was therefore designed to evaluate effects of cow genotype and concentrate CP level on nutrient digestibility, energy utilization and CH4 emissions of dairy cows offered fresh grass based diets. Twelve multiparous lactating dairy cows (6 Holstein and 6 Holstein × Swedish Red) were blocked into 3 groups within each breed and assigned to low, medium or high CP concentrate diet (14.1, 16.1 and 18.1 % on dry matter (DM) basis), respectively, in a 3-period changeover study (25-d / period). Total diets contained (DM basis) 32.8 % concentrates and 67.2 % perennial ryegrass, which was harvested daily. All measurements were undertaken during the final 6-d of each period; digestibility measurements for 6-d and calorimetric measurements in respiration chambers for 3-d. Feed intake and milk production data were reported in a previous paper. No significant interaction between concentrate CP level and cow genotype on any parameter was observed. Concentrate CP level had no significant effect on any energy utilization parameter, except for urinary energy output which was positively related to concentrate CP level. Similarly concentrate CP content had no effect on CH4 emission (g/d), CH4 per kg feed intake or nutrient digestibility. The crossbreeding of Holstein cows significantly reduced gross energy, digestible energy and metabolizable energy intake, heat production and milk energy output. However, cow genotype had no significant effects on energy utilization efficiency or CH4 parameters. Furthermore, the present study yielded a value for gross energy lost as CH4 (5.6 %) on fresh grass-based diets that is lower than the widely accepted value of 6.5 %. The present findings indicate reducing concentrate CP content from 18.1 to 14.1 % may not be a successful approach to alleviate CH4 emissions from lactating dairy cows offered good quality fresh grass, however grazing cows could be offered a low CP concentrate without compromising energy utilization efficiency. Further research is needed to investigate whether larger differences in dietary CP content may yield positive results

    Effects of crude protein levels in concentrate supplements on animal performance and nitrogen utilization of lactating dairy cows fed fresh-cut perennial grass

    Get PDF
    There are increased concerns regarding N pollution of air and ground water from grazing cattle. Although a number of studies have investigated mitigation strategies for N output from dairy cows fed conserved forages and concentrates, similar research on fresh-cut grass in addition to production parameters is limited. Therefore the current study, using 3 dietary treatments and incorporating 2 genotypes, was designed to evaluate the effects of concentrate crude protein (CP) level on animal production and N utilization efficiency (NUE) of lactating dairy cows. Twelve multiparous cows (6 Holstein and 6 Holstein × Swedish Red) were used in a change-over study with three 25-d periods and 3 diet treatments; low, medium and high CP concentrate (14.1, 16.1 and 18.1% respectively, dry matter (DM) basis) fed at 32.8% DM intake in combination with good quality zero-grazed perennial ryegrass (18.2% CP, DM basis). Each period consisted of an adaption phase (18-d) housed as a single group, 1-d adaption in individual stalls and a 6-d measurement phase with feed intake and feces, urine and milk output recorded. There was no significant interaction between cow genotype and concentrate CP level on any animal performance or NUE parameters. Total DM intake, milk yield and composition and NUE were not affected by dietary treatment. However, increasing concentrate CP level increased (i) N intake by 42 g/d and excretion in urine and manure, by 38 and 40 g/d, respectively, and (ii) the ratio of urine N over manure N. Feeding high CP, rather than low CP concentrate, increased milk urea N (MUN) content by 3.6 mg/dL and total MUN output by 1.08 g/d. Crossbred cows had lower grass DM intake, total DM intake, total N intake and consequently energy-corrected milk yield. However, cow genotype had no significant effect on NUE or MUN parameters. Equations have been developed to predict urine N excretion using MUN output as sole predictor or in combination with dietary CP level. The present study indicated that when grazing cows are fed on good quality pasture, feeding concentrates with a protein content as low as 14.1% may not negatively affect productivity. In addition, reducing concentrate CP concentration may be a successful method of reducing urinary N excretion of lactating dairy cattle on pasture-based systems, but further research is needed to investigate long-term effects of supplementary concentrate CP content on milk production

    Effect of substituting fresh-cut perennial ryegrass with fresh-cut white clover on bovine milk fatty acid profile

    Get PDF
    BACKGROUND: Including forage legumes in dairy systems can help address increasing environmental/economic concerns about perennial ryegrass monoculture pastures. This work investigated the effect of substituting fresh-cut grass with increasing quantities of fresh-cut white clover (WC) on milk fatty acid (FA) profile and transfer efficiency of dietary linoleic (LA) and α-linolenic (ALNA) acids to milk fat. Three groups of three crossbred dairy cows were used in a 3×3 cross-over design. Dietary treatments were 0 g kg-1 WC+600 g kg-1 grass, 200 g kg-1 WC+400 g kg-1 grass, 400 g kg-1 WC+200 g kg-1 grass. All treatments were supplemented with 400 g kg-1 concentrates on a dry matter basis. Cows had a 19-d adaptation period to the experimental diet before a 6-d measurement period in individual tie stalls. RESULTS: Increasing dietary WC did not affect dry matter intake, milk yield or milk concentrations of fat, protein or lactose. Milk polyunsaturated FA concentrations (total omega-3, total omega-6, LA and ALNA) and transfer efficiency of LA and ALNA were increased with increasing dietary WC supply. CONCLUSION: Inclusion of WC in pastures may increase concentrations of nutritionally beneficial FA, without influencing milk yield and basic composition, but any implications on human health cannot be drawn

    Concentrations of phytoestrogens in conventional, organic and free-range retail milk in England

    Get PDF
    The effect of dairy management system (conventional, CNV; organic, ORG; free-range, FRG) and month on retail milk phytoestrogen composition was assessed for 12 consecutive months. ORG milk contained more secoisolariciresinol, matairesinol, lariciresinol, sum of plant lignans, daidzein, genistein, formononetin, naringenin, equol, sum of isoflavones and coumestrol, than CNV and FRG milk. This may be explained by the higher supply of pasture, and grazed or ensiled clover, in ORG dairy diets. Seasonal variation in milk phytoestrogen concentrations was higher for ORG than CNV and FRG systems. Phytoestrogen composition did not vary between FRG and CNV milk. Consuming organic milk can increase intake of potentially beneficial lignans and isoflavonoids, and in particular equol; but, any effects on human health from such milk compositional differences cannot be implied

    Fat composition of organic and conventional retail milk in northeast England

    Get PDF
    This study of UK retail milk identified highly significant variations in fat composition. The survey, conducted over 2 yr replicating summer and winter, sampled 22 brands, 10 of which indicated organic production systems. Results corroborate earlier farm-based findings considering fat composition of milk produced under conventional and organic management. Organic milk had higher concentrations of beneficial fatty acids (FA) than conventional milk, including total polyunsaturated fatty acids (PUFA; 39.4 vs. 31.8 g/kg of total FA), conjugated linoleic acid cis-9,trans-11 (CLA9; 7.4 v 5.6 g/kg of FA), and α-linolenic acid (α-LN; 6.9 vs. 4.4 g/kg of FA). As expected, purchase season had a strong effect on fat composition: compared with milk purchased in winter, summer milk had a lower concentration of saturated fatty acids (682 vs. 725 g/kg of FA) and higher concentrations of PUFA (37.6 vs. 32.8 g/kg of FA), CLA9 (8.1 vs. 4.7 g/kg of FA), and α-LN (6.5 vs. 4.6 g/kg of FA). Differences identified between sampling years were more surprising: compared with that in yr 2, milk purchased in year 1 had higher concentrations of PUFA (37.5 vs. 32.9 g/kg of FA), α-LN (6.0 vs. 5.1 g/kg of FA), and linoleic acid (19.9 vs. 17.5 g/kg of FA) and lower concentrations of C16:0 and C14:0 (332 vs. 357 and 110 vs. 118 g/kg of FA, respectively). Strong interactions were identified between management and season as well as between season and year of the study. As in the earlier farm studies, differences in fat composition between systems were greater for summer compared with winter milk. Large between-year differences may be due to changes in weather influencing milk composition through forage availability, quality, and intake. If climate change predictions materialize, both forage and dairy management may have to adapt to maintain current milk quality. Considerable variation existed in milk fat composition between brands

    Sustainable intensification? Increased production diminishes omega-3 content of sheep milk

    Get PDF
    Intensifying agricultural production alters food composition, but this is often ignored when assessing system sustainability, yet it could compromise consumers’ health and the concept of ‘sustainable diets’. Here we consider milk composition from Mediterranean dairy sheep, finding inferior fatty acid (FA) profiles with respect to consumer health as a result of a more intensive system of production. Semi-intensive management did produce 57% more milk per ewe with 20% lower fat content, but inferior fat composition. Milk had a nutritionally poorer fatty acid (FA) profile, with 18% less omega-3 FA (n-3) (19% less long-chain n-3) and 7% less monounsaturated FA but 3% more saturated FA (9% higher in C14:0) concentrations compared with ewes under traditional, extensive management. Redundancy analysis identified close associations between fat composition and animal diets, particularly concentrate supplementation and grazing cultivated pasture - n-3 was associated with grazing diverse, native mountain pastures. The paper questions if identifying such key elements in traditional systems could be deployed for ‘sustainable intensification’ to maintain food quality whilst increasing output

    Evaluation and prediction of nitrogen use efficiency and outputs in faeces and urine in beef cattle

    Get PDF
    Beef cattle production is valuable to food security, contributing meat of high nutritional value. However, beef cattle are rather inefficient in utilising dietary nitrogen (N), thus excreting substantial amounts of N in their urine and faeces and imposing an environmental burden. The aim of this study was to evaluate the main dietary factors affecting N use efficiency (NUE) in beef cattle and develop prediction models for N excretion in manure, faeces and urine. This knowledge is essential for the development and evaluation of cost-effective N mitigation strategies. A database of 289 treatment means was constructed from 69 published studies and 1194 animals. Data included diet contents of N, dry matter (DM), organic matter (OM), neutral-detergent fibre (NDF), acid-detergent fibre (ADF), ether extract, starch, ash, gross energy (GE), metabolisable energy (ME), and outputs of N in manure, in urine or in faeces. Regression equations to predict N outputs in manure (MNO), urine (UNO) and faeces (FNO), as well as various NUE indicators, were developed using residual maximum likelihood analysis. Evaluation of new and existing models was performed using the mean prediction error (MPE) to describe prediction accuracy. Manure, urine and faeces N outputs were predicted with improved accuracy (MPE from 0.557 to 0.162; from 0.764 to 0.208; and from 0.458 to 0.177, respectively) when DM or OM digestibilities, and/or diet contents of N, NDF, ADF, Starch, OM, GE, ME, and/or forage proportion in the diet were added as predictors in different equations already containing either DM intake, N intake or body weight as primary predictor. New and existing models displayed an under-prediction of N outputs at the highest range of actual N outputs (when MNO > 207 g/d, UNO > 109 g/d). However, some of the new equations had improved overall accuracy (best MPE for MNO, UNO and FNO being 0.162, 0.208 and 0.177, respectively) and, when DM digestibility, and contents of N, NDF, Starch and ME were added as predictors in different equations, the extent of this under-prediction was also reduced (occurring when MNO > 208 g/d, UNO > 132 g/d). The regression models for NUE, demonstrated that diets which are more digestible and contain less N and fibre and more ME, may reduce N excretions, but mitigation strategies will also need to account for the potential effect on animal productivity and health

    How should we turn data into decisions in AgriFood?

    Get PDF
    The AgriFood supply chain is under significant pressures related to food security, climate change, and consumer demands for affordable and higher quality food. Various technologies are already deployed producing a large amount of data, which can be utilised to guide decision-making to improve productivity, reduce wastage, and increase traceability across the AgriFood supply chain. Several examples of the use of data are given, including improving efficiency in livestock production, supporting automation and use of robotics in crop production, increasing food safety and evidencing its provenance. The opportunities and ways forward were discussed at a workshop in November 2017, run by the Society of Chemical Industry and the Knowledge Transfer Network in the UK. This paper presents a summary of the key messages from the presentations and focus-group discussions during this event, as interpreted by the authors. A number of challenges in digitalisation of the AgriFood supply chain are discussed, such as low inter-operability of different data sets, silo mentality, low willingness to share data and a significant skills gap. Various approaches are presented that could help to unlock the benefits of using data, from practical support to producers and addressing skills gaps, to industrial leadership and the role of government departments and regulatory bodies in leading by example. Looking forward, data are already revolutionising the AgriFood supply chain, however, the benefits will remain piecemeal until the leaders of today are able to bring together the disparate groups into a cohesive whole
    • …
    corecore