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Milk fat is an important nutrient for young animals and humans, and its composition [fatty acids (FA)] may vary broadly. The objective of this study was to describe the development of global FA models for high-throughput Fourier transform infrared milk analysers. The developed models for major FA, FA grouped by chain length, by degree of unsaturation and by their origin, showed good accuracy, repeatability and correlation to gas chromatography. Moderate performance was obtained for low concentration FA (short chain, polyunsaturated and trans). Possible practical applications could be to enhance dairy products, optimise milk processing and/or optimise dairy cow performance through improved feeding and management.

A group of milk components that has shown potential to be predicted with milk spectra is milk minerals. Milk minerals are important for human health and cow health. Having an inexpensive and fast way to measure milk mineral concentrations would open doors for research, herd management, and selective breeding. The first aim of this study was to predict milk minerals with infrared milk spectra. Additionally, milk minerals were predicted with infrared-predicted fat, protein, and lactose content. The second aim was to perform a genetic analysis on infrared-predicted milk minerals, to identify QTL, and estimate variance components. For training and validating a multibreed prediction model for individual milk minerals, 264 Danish Jersey cows and 254 Danish Holstein cows were used. Partial least square regression prediction models were built for Ca, Cu, Fe, K, Mg, Mn, Na, P, Se, and Zn based on 80% of the cows, selected randomly. Prediction models were externally validated with 8 herds based on the remaining 20% of the cows. The prediction models were applied on a population of approximately 1,400 Danish Holstein cows with 5,600 infrared spectral records and 1,700 Danish Jersey cows with 7,200 infrared spectral records. Cows from this population had 50k imputed genotypes. Prediction accuracy was good for P and Ca, with external R2 ≥ 0.80 and a relative prediction error of 5.4% for P and 6.3% for Ca. Prediction was moderately good for Na with an external R2 of 0.63, and a relative error of 18.8%. Prediction accuracies of milk minerals based on infrared-predicted fat, protein, and lactose content were considerably lower than those based on the infrared milk spectra. This shows that the milk infrared spectrum contains valuable information on milk minerals, which is currently not used. Heritability for infrared-predicted Ca, Na, and P varied from low (0.13) to moderate (0.36). Several QTL for infrared-predicted milk minerals were observed that have been associated with gold standard milk minerals previously. In conclusion, this study has shown infrared milk spectra were good at predicting Ca, Na, and P in milk. Infrared-predicted Ca, Na, and P had low to moderate heritability estimates. A group of milk components that has shown potential to be predicted with milk spectra is milk minerals. Milk minerals are important for human health and cow health. Having an inexpensive and fast way to measure milk mineral concentrations would open doors for research, herd management, and selective breeding. The first aim of this study was to predict milk minerals with infrared milk spectra. Additionally, milk minerals were predicted with infrared-predicted fat, protein, and lactose content. The second aim was to perform a genetic analysis on infrared-predicted milk minerals, to identify QTL, and estimate variance components. For training and validating a multibreed prediction model for individual milk minerals, 264 Danish Jersey cows and 254 Danish Holstein cows were used. Partial least square regression prediction models were built for Ca, Cu, Fe, K, Mg, Mn, Na, P, Se, and Zn based on 80% of the cows, selected randomly. Prediction models were externally validated with 8 herds based on the remaining 20% of the cows. The prediction models were applied on a population of approximately 1,400 Danish Holstein cows with 5,600 infrared spectral records and 1,700 Danish Jersey cows with 7,200 infrared spectral records. Cows from this population had 50k imputed genotypes. Prediction accuracy was good for P and Ca, with external R2 ≥ 0.80 and a relative prediction error of 5.4% for P and 6.3% for Ca. Prediction was moderately good for Na with an external R2 of 0.63, and a relative error of 18.8%. Prediction accuracies of milk minerals based on infrared-predicted fat, protein, and lactose content were considerably lower than those based on the infrared milk spectra. This shows that the milk infrared spectrum contains valuable information on milk minerals, which is currently not used. Heritability for infrared-predicted Ca, Na, and P varied from low (0.13) to moderate (0.36). Several QTL for infrared-predicted milk minerals were observed that have been associated with gold standard milk minerals previously. In conclusion, this study has shown infrared milk spectra were good at predicting Ca, Na, and P in milk. Infrared-predicted Ca, Na, and P had low to moderate heritability estimates.

Among the dairy sector's current concerns, the as-sessment of global animal health status is a complex challenge. Its multidimensionality means that global monitoring tools are rarely considered. Instead, specific disease detection is often studied separately and, due to financial and ethical issues, uses small-scale data sets focusing on few biomarkers. Several studies have already been conducted using milk Fourier transform mid-infrared (FT-MIR) spectroscopy to detect mastitis and lameness or to quantify health-related biomarkers in milk or blood. Those studies are relevant but they focus mainly on one biomarker or disease. To solve this issue and the small-scale data set, in this study, we proposed a holistic approach using big data obtained from milk recording, including milk yield, somatic cell count, and 27 FT-MIR-based predictors related to milk composition and animal health status. Using 740,454 records collected from 114,536 first-parity Holstein cows in southern Belgium, we performed repeated unsupervised learning algorithms based on Ward's agglomerative hierarchical clustering method to find potential interesting patterns. A divide-and-conquer approach was used to overcome the limitation of computational resources in clustering a relatively large data set. Five groups of records were identified. Differences observed in the fourth group suggested a relationship to metabolic disorders. The fifth group seemed to be related to mastitis. In a second step, we performed a partial least squares discriminant analysis (PLS-DA) to predict the probability of belonging to those specific groups for the entire data set. The obtained global ac-curacy was 0.77 and the balanced accuracy (i.e., the mean between sensitivity and specificity) of discrimi-nating the fourth and fifth groups was 0.88 and 0.96, respectively. Then, a validation of the interpretation of those groups was performed using 204 milk and blood reference records. The predicted probability associated with the metabolic disorders issue had significant cor-relations of 0.54 with blood beta-hydroxybutyrate, 0.44 with blood nonesterified fatty acids, -0.32 with blood glucose, -0.23 with milk glucose-6-phosphate, and 0.38 with milk isocitrate. In contrast, the predicted prob-ability of belonging to the mastitis group had correla-tions of 0.69 with milk lactate dehydrogenase, 0.46 with milk N-acetyl-beta-D-glucosaminidase, -0.18 with milk free glucose, and 0.16 with milk glucose-6-phosphate. Consequently, these results suggest that the obtained quantitative traits indirectly reflect some of the main health disorders in dairy farming and could be used to monitor dairy cows on a large scale. By using unsuper-vised learning on large-scale milk recording data and then validating the pattern using reference laboratory measures, we propose a new approach to quickly assess dairy cow health status.

In this study, a new affinity process was developed for the purification of Lactoperoxidase with synthesized sixteen aminobenzohydrazide derivatives. For this purpose, ligands were covalently bound to CNBr-activated Sepharose-4B-L-tyrosine matrix and affinity columns were prepared, and LPO was purified in one step with high yield and purity. Among all synthesized molecules, the 4-amino-3-bromo-2-methylbenzohydrazide molecule had a high usable potential in the purification of Lactoperoxidase from mammalian milk. Lactoperoxidase was purified 411.8 times with a yield of 17.38 % from goat milk, 187.25 times with a yield of 9.72 % buffalo milk, 2772.4 times with a yield of 18.98 % from bovine milk, and 1246.65 times with a yield of 4.43 % from sheep milk. It was demonstrated for the first time that aminobenzohydrazide molecules could be used as ligands in the purification of Lactoperoxidase enzyme.

The intestinal immune barrier is considered to be the gatekeeper of the human body and rapidly develops directly after birth. Many pre- and postnatal factors influence the development of the gut-barrier, which is composed of the microbiota, the mucus, the epithelial layer and the mucosal immune system. Even minor disturbances during barrier development can have consequences for health far into adulthood. Here we critically discuss the current knowledge on which pre- and postnatal factors influence development, maturation, and maintenance of the gut immune barrier. Human milk has a unique composition and is the gold standard for adequate development of the intestinal immune barrier. Not only the influence of human milk oligosaccharides (HMOs) but also that of glycoproteins (HMGPs) is reviewed. We discuss the influence of maternal genetic factors, such as the secretor and Lewis phenotypes on breast milk fucosylation and sialylation of HMOs and HMGPs. This diversity in HMOs and HMPGs influences microbiota composition and also the development of the immune barrier. Cow milk-derived infant formula is often being used as an alternative for human breast milk. The consequences of this for proper development of the intestinal immune barrier and, in particular, the differences in the type of oligosaccharides and glycosylation patterns (sialic and fucose composition) between cow and human milk are critically discussed. Current and prospective strategies to promote proper gut-immune maturation are proposed. These might include more personalized infant formulas when breast milk is not an option.

The role of unregulated and inappropriate dispensing, and use of antibiotics remains significant in the development of antimicrobial resistance in infectious disease endemic regions of developing countries. The exposure to antibiotics from unfamiliar and unsuspecting sources such as drinking water and food, and adulterated herbal medicines remains a cause for concern. A sensitive SPE-LC-MS/MS method was developed and validated for the quantification and qualification of 12 antibiotics, including amoxicillin, clavulanic acid, metronidazole, ampicillin, cefuroxime, tetracycline, ceftriaxone, sulphamethoxazole, trimethoprim, ciprofloxacin, benzylpenicillin, and erythromycin, in the urine of healthy volunteers. The method was linear (r(2) > 0.98) within the concentration range 50-5000 ngmL(-1) for all the analytes. Instrument precision of 8-27% and 4-21% at 100 and 1000 ngmL(-1) levels were demonstrated. High mean recoveries between 71 and 125% with minimal variations were obtained for all compounds in the accuracy study. Limits of detection and quantification ranged between 70.3-271.0 ngmL(-1) and 213-821 ngmL(-1) respectively. The validated method successfully detected and quantified 9 of the 12 analytes, with the exception of clavulanic acid, cefuroxime, and benzylpenicillin. Most of the samples contained one analyte (52, 86.7%), with a handful containing two (7, 11.7%) and three analytes (1, 1.7%). Ciprofloxacin was the modal analyte detected (17, 24.6%), with amoxicillin and trimethoprim recording the average lowest (22.76 x 10(3) ngmL(-1)) and highest concentrations (255.47 x 10(3) ngmL(-1)) respectively. The developed method is a useful tool for non-invasive monitoring of consumption and the irrational use of antibiotics in microbial resistant-prone regions of the world.

In high-yielding dairy cattle, severe postpartum negative energy balance is often associated with metabolic and infectious disorders that negatively affect production, fertility, and welfare. Mobilization of adipose tissue associated with negative energy balance is reflected through an increased level of nonesterified fatty acids (NEFA) in the blood plasma. Earlier, identification of negative energy balance through detection of increased blood plasma NEFA concentration required laborious and stressful blood sampling. More recently, attempts have been made to predict blood NEFA concentration from milk samples. In this study, we aimed to develop and validate a model to predict blood plasma NEFA concentration using the milk mid-infrared (MIR) spectra that are routinely measured in the context of milk recording. To this end, blood plasma and milk samples were collected in wk 2, 3, and 20 postpartum for 192 lactations in 3 herds. The blood plasma samples were taken in the morning, and representative milk samples were collected during the morning and evening milk sessions on the same day. To predict plasma NEFA concentration from the milk MIR spectra, partial least squares regression models were trained on part of the observations from the first herd. The models were then thoroughly validated on all other observations of the first herd and on the observations of the 2 independent herds to explore their robustness and wide applicability. The final model could accurately predict blood plasma NEFA concentrations 1.2 mmol/L NEFA, the model clearly underestimated the true level. Additionally, we found that morning blood plasma NEFA levels were predicted with significantly higher accuracy using MIR spectra of evening milk samples compared with MIR spectra of morning samples, with root mean square error of prediction values of, respectively, 0.182 and 0.197 mmol/L, and R2 values of 0.613 and 0.502. These results suggest a time delay between variations in blood plasma NEFA and related milk biomarkers. Based on the MIR spectra of evening milk samples, cows at risk for negative energy status, indicated by detrimental morning blood plasma NEFA levels (>0.6 mmol/L), could be identified with a sensitivity and specificity of, respectively, 0.831 and 0.800. As this model can be applied to millions of historical and future milk MIR spectra, it opens an opportunity for regular metabolic screening and improved resilience phenotyping. ispartof: JOURNAL OF DAIRY SCIENCE vol:103 issue:7 pages:6422-6438 ispartof: location:United States status: published

Blood biomarkers may be used to detect physiological imbalance and potential disease. However, blood sampling is difficult and expensive, and not applicable in commercial settings. Instead, individual milk samples are readily available at low cost, can be sampled easily and analysed instantly. The present observational study sampled blood and milk from 234 Holstein dairy cows from experimental herds in six European countries. The objective was to compare the use of three different sets of milk biomarkers for identification of cows in physiological imbalance and thus at risk of developing metabolic or infectious diseases. Random forests was used to predict body energy balance (EBAL), index for physiological imbalance (PI-index) and three clusters differentiating the metabolic status of cows created on basis of concentrations of plasma glucose, β-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA) and serum IGF-1. These three metabolic clusters were interpreted as cows in balance, physiological imbalance and “intermediate cows” with physiological status in between. The three sets of milk biomarkers used for prediction were: milk Fourier transform mid-IR (FT-MIR) spectra, 19 immunoglobulin G (IgG) N-glycans and 8 milk metabolites and enzymes (MME). Blood biomarkers were sampled twice; around 14 days after calving (days in milk (DIM)) and around 35 DIM. MME and FT-MIR were sampled twice weekly 1-50 DIM whereas IgG N-glycan were measured only four times. Performances of EBAL and PI-index predictions were measured by coefficient of determination (R2cv) and root mean squared error (RMSEcv) from leave-one-cow-out cross-validation (cv). For metabolic clusters, performance was measured by sensitivity, specificity and global accuracy from this cross-validation. Best prediction of PI-index was obtained by MME (R2cv = 0.40 (95% CI: 0.29-0.50) at 14 DIM and 0.35 (0.23-0.44) at 35 DIM) while FT-MIR showed a better performance than MME for prediction of EBAL (R2cv = 0.28 (0.24-0.33) vs 0.21 (0.18-0.25)). Global accuracies of predicting metabolic clusters from MME and FT-MIR were at the same level ranging from 0.54 (95% CI: 0.39-0.68) to 0.65 (0.55-0.75) for MME and 0.51 (0.37-0.65) to 0.68 (0.53-0.81) for FT-MIR. R2cv and accuracies were lower for IgG N-glycans. In conclusion, neither EBAL nor PI-index were sufficiently well predicted to be used as a management tool for identification of risk cows. MME and FT-MIR may be used to predict the physiological status of the cows, while the use of IgG N-glycans for prediction still needs development. Nevertheless, accuracies need to be improved and a larger training data set is warranted.

Background Infrared spectral analysis of milk is cheap, fast, and accurate. Infrared light interacts with chemical bonds present inside the milk, which means that Fourier transform infrared milk spectra are a reflection of the chemical composition of milk. Heritability of Fourier transform infrared milk spectra has been analysed previously. Further genetic analysis of Fourier transform infrared milk spectra could give us a better insight in the genes underlying milk composition. Breed influences milk composition, yet not much is known about the effect of breed on Fourier transform infrared milk spectra. Improved understanding of the effect of breed on Fourier transform infrared milk spectra could enhance efficient application of Fourier transform infrared milk spectra. The aim of this study is to perform a genome wide association study on a selection of wavenumbers for Danish Holstein and Danish Jersey. This will improve our understanding of the genetics underlying milk composition in these two dairy cattle breeds. Results For each breed separately, fifteen wavenumbers were analysed. Overall, more quantitative trait loci were observed for Danish Jersey compared to Danish Holstein. For both breeds, the majority of the wavenumbers was most strongly associated to a genomic region on BTA 14 harbouring DGAT1. Furthermore, for both breeds most quantitative trait loci were observed for wavenumbers that interact with the chemical bond C-O. For Danish Jersey, wavenumbers that interact with C-H were associated to genes that are involved in fatty acid synthesis, such as AGPAT3, AGPAT6, PPARGC1A, SREBF1, and FADS1. For wavenumbers which interact with –OH, associations were observed to genomic regions that have been linked to alpha-lactalbumin. Conclusions The current study identified many quantitative trait loci that underlie Fourier transform infrared milk spectra, and thus milk composition. Differences were observed between groups of wavenumbers that interact with different chemical bonds. Both overlapping and different QTL were observed for Danish Holstein and Danish Jersey.

In this work, the known antiproliferative activity of the untreated milk fat globule membrane (MFGM) against human colon cancer cells was employed to test the hypothesis that the supramolecular structure of the MFGM is of important biological significance. The results indicated that there is a relationship between the extent of thermal denaturation and the loss of antiproliferative capacity. There was also a clear reduction of the biological activity, when the MFGM was treated by hydrolysis using trypsin or phospholipase A(2), enzymes specific either for the protein or the phospholipids components present in the MFGM. It was concluded that the bioactivity of the MFGM can not be explained only by the presence of bioactive components, but that their structural organization plays a critical role in the antiproliferative activities of the extracts. Practical applications The milk fat globule membrane (MFGM) is characterized by a complex composition and structure, with biological significance. It is known that with processing, the composition of the MFGM is modified, due to protein-protein interactions at the interface. In this work, the MFGM was isolated from untreated milk and while maintaining its overall composition, its molecular and supramolecular structures were modified using heating or specific hydrolysis to the protein or phospholipids' components. All targeted modifications affected the bioefficacy of the MFGM against colon cancer cells, thus demonstrating the importance of processing history on the functionality of the MFGM.

The aim of this study was to investigate the sources of variation of milk fatty acids (FA) routinely predicted by mid-infrared spectroscopy in Holstein-Friesian (HF), Brown Swiss (BS), Simmental (SI) and Alpine Grey (AG) cattle breeds. A linear mixed model was used to analyse the data which included 153,801 individual milk samples from 14,301 cows. Fixed effects included in the model were breed, month of sampling, year of sampling, stage of lactation, parity and first order interactions between them, and random effects were herd nested within breed, cow nested within breed and the residual error. Milk of AG cows exhibited the lowest content of saturated FA and the greatest content of unsaturated FA, whereas milk of BS had an opposite pattern. Holstein-Friesian and SI were intermediate between AG and BS breeds for all the FA except for total C18:1, which was the greatest in HF. Saturated FA, C14:0 and C16:0 increased from calving until 120 days in milk, whereas unsaturated FA and C18:1 decreased. First parity cows produced milk with lower concentration of de novo FA than multiparous animals. The greatest content of unsaturated FA and C18:1 was observed in summer, whereas saturated FA, C14:0, C16:0 and C18:0 decreased in summer and increased in winter. The differences in milk FA profile among breeds are useful for genetic selection and for feeding strategies.

This Research Communication describes the adaptation and testing of an RP-HPLC method, previously tested for the determination of lactoferrin (LF) in whey, for its applicability to determine milk lactoferrin content. Milk samples of various species, namely, ovine, caprine, bovine, donkey and human milk, were tested. The advantage of this RP-HPLC method includes speed and convenience, as it does not include extensive pretreatment or separation steps. A simple pre-treatment step was added in order to remove fat and proteins of the casein family and the samples were tested. The results varied in terms of elution of the LF peak both between the milk of the different species as well as from the initial application on whey. The peak resolution was satisfactory in the cases of ovine, bovine and donkey milk samples while for caprine and human milk an interference with other peaks was observed. Nevertheless, quantification of LF was found possible for all samples. This new application of the modified method will allow the determination of LF in milk samples of the tested species either for everyday analysis or as a useful qualitative screening for presence or absence of LF. ispartof: JOURNAL OF DAIRY RESEARCH vol:86 issue:2 pages:238-241 ispartof: location:England status: published

Milk is an important protein source in human diets, providing around 32 g protein/l (for bovine milk, which constitutes some 85% of global consumption). The most abundant milk proteins are α-lactalbumin, β-lactoglobulin, αs-casein, β-casein, and κ-casein. Besides their nutritional value, milk proteins play a crucial role in the processing properties of milk, such as solubility, water bonding, heat stability, renneting and foaming, among others. In addition, and most importantly for this review, these proteins are the main source of bioactive components in milk. Due to the wide range of proposed beneficial effects on human health, milk proteins are considered as potential ingredients for the production of health-promoting functional foods. However, most of the evidence for bioactive effects comes from in vitro studies, and there is a need for further research to fully evaluate the true potential of milk-derived bioactive factors. Animal genetics and animal nutrition play an important role in the relative proportions of milk proteins and could be used to manipulate the concentration of specific bioactive peptides in milk from ruminants. Unfortunately, only a few studies in the literature have focused on changes in milk bioactive peptides associated to animal genetics and animal nutrition. The knowledge described in the present review may set the basis for further research and for the development of new dairy products with healthy and beneficial properties for humans.

Dairy fat is one of the most complex natural fats because of its fatty acid (FA) composition. Ruminant dairy fat contains more than 400 different FA varying in carbon chain length, and degree, position and configuration of unsaturation. The following article reviews the different methods available to analyze FA (both total and free) in milk and dairy products. The most widely used methodology for separating and analyzing dairy FA is gas chromatography, coupled to a flame ionization detector (CG-FID). Alternatively, gas chromatography coupled to a mass spectrometer (GC-MS) is also used. After lipid extraction, total FA (TFA) are commonly converted into their methyl esters (fatty acid methyl esters, FAME) prior to chromatographic analysis. In contrast, free FA (FFA) can be analyzed after conversion to FAME or directly as FFA after extraction from the product. One of the key questions when analyzing FAME from TFA is the selection of a proper column for separating them, which depends mainly on the objective of the analysis. Quantification is best achieved by the internal standard method. Recently, near-infrared spectroscopy (NIRS), Raman spectroscopy (RS) and nuclear magnetic resonance (NMR) have been reported as promising techniques to analyze FA in milk and dairy products.

Red clover (Trifolium pratense L.) is the predominant legume used in northern European agriculture. Official red clover variety trials are conducted by Natural Resources Institute Finland (Luke) to determine the value of field crop varieties. The trials used for the current analysis were conducted in Luke units in southern Finland (Mikkeli) and northern Finland (Ruukki) in two consecutive years. Plant samples for isoflavone analyses were collected from four varieties grown as four replicates and harvested twice during both growing seasons. The four main isoflavones biochanin A, genistein, daidzein and formononetin were analysed using high performance liquid chromatography. Total phytoestrogen content in the varieties varied in the range of 11.2−14.8 mg g-1 dry matter (DM). The variety and the time of harvest had most effect on the isoflavone, especially formononetin, contents of red clover. A more northern growing area and challenging weather conditions were associated with increased isoflavone concentrations.

Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on whey basic protein isolate as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is obtained by ion exchange chromatography of skimmed cow's milk. The applicant intends to market the NF in infant and follow-on formulae and meal replacement beverages, dietary foods for special medical purposes and as food supplements. The highest estimated intake of the NF based on the proposed uses and use levels would be 24.8 mg/kg body weight (bw) per day in infants and 27.8 in toddlers. The information provided on composition, specifications, production process and stability of the NF do not raise safety concerns. Taking into account the composition of the NF and the intended use levels, the Panel considers that the consumption of the NF is not nutritionally disadvantageous. The Panel considers that there is no concern with respect to genotoxicity. The no observed adverse effect level (NOAEL) of a subchronic 13-week rat study was 2000 mg/kg bw per day. Considering the source, the production process and nature of the NF, the Panel considers the margin of exposure (MOE) of 154 to be sufficient for the adult population (on a high-estimated intake of 13 mg/kg bw). For infants and toddlers, the MOE would be at least 81 and 72, respectively. Taking into account the composition of the NF, its source, the history of consumption of the main components of the NF, the production process and that the NOAEL in a subchronic rat study was the highest dose tested the Panel considers that also the MOE for infants and toddlers are sufficient. The Panel concludes that the novel food ingredient, whey basic protein isolate, is safe under the proposed uses and use levels. (C) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Background Despite of the presence of sulfhydryl oxidases (SOXs) in the secretomes of industrially relevant organisms and their many potential applications, only few of these enzymes have been biochemically characterized. In addition, basic functions of most of the SOX enzymes reported so far are not fully understood. In particular, the physiological role of secreted fungal SOXs is unclear. Results The recently identified SOX from Aspergillus tubingensis (AtSOX) was produced, purified and characterized in the present work. AtSOX had a pH optimum of 6.5, and showed a good pH stability retaining more than 80% of the initial activity in a pH range 4-8.5 within 20 h. More than 70% of the initial activity was retained after incubation at 50 °C for 20 h. AtSOX contains a non-covalently bound flavin cofactor. The enzyme oxidised a sulfhydryl group of glutathione to form a disulfide bond, as verified by nuclear magnetic resonance spectroscopy. AtSOX preferred glutathione as a substrate over cysteine and dithiothreitol. The activity of the enzyme was totally inhibited by 10 mM zinc sulphate. Peptide- and protein-bound sulfhydryl groups in bikunin, gliotoxin, holomycin, insulin B chain, and ribonuclease A, were not oxidised by the enzyme. Based on the analysis of 33 fungal genomes, SOX enzyme encoding genes were found close to nonribosomal peptide synthetases (NRPS) but not with polyketide synthases (PKS). In the phylogenetic tree, constructed from 25 SOX and thioredoxin reductase sequences from IPR000103 InterPro family, AtSOX was evolutionary closely related to other Aspergillus SOXs. Oxidoreductases involved in the maturation of nonribosomal peptides of fungal and bacterial origin, namely GliT, HlmI and DepH, were also evolutionary closely related to AtSOX whereas fungal thioreductases were more distant. Conclusions AtSOX (55 kDa) is a fungal secreted flavin-dependent enzyme with good stability to both pH and temperature. A Michaelis-Menten behaviour was observed with reduced glutathione as a substrate. Based on the location of SOX enzyme encoding genes close to NRPSs, SOXs could be involved in the secondary metabolism and act as an accessory enzyme in the production of nonribosomal peptides. Electronic supplementary material The online version of this article (10.1186/s12858-017-0090-4) contains supplementary material, which is available to authorized users.

Plasmin is a protease in milk, which concentration is increased during mastitis. The aim of the study was design and characterize short, tailor made fluorogenic substrates for plasmin to see differences in plasmin activity in healthy milk compared to mastitic milk. According to the specificity matrix of plasmin, containing 125 currently known plasmin substrates, six novel plasmin specific substrates were designed and characterized. Eight other substrates were insensitive for plasmin, which was in line with our expectations. The plasmin-sensitive substrates showed no cross-reactivity with proteases from mastitogenic bacteria in vitro. A proof of concept to distinguish healthy milk from mastitic milk is described. Potentially, these substrates present a rapid alternative to the currently established methodologies to detect mastitis in milk.

We have developed a rapid mastitis detection test based on the immobilization of tag-specific antibody molecules, the binding of double-tagged amplicons, and as a secondary signal a conjugate of black carbon nanoparticles having molecules of a fusion protein of neutrAvidin and alkaline phosphatase at their surface. The antibodies were inkjet printed onto three different nitrocellulose membrane slides, Unisart (Sartorius), FAST (GE Whatman), and Oncyte-Avid (Grace-Biolabs), and the final assay signals on these slides were compared. The blackness of the spots was determined by flatbed scanning and assessment of the pixel gray volume using TotalLab image analysis software. The black spots could be easily read by the naked eye. We successfully demonstrated the detection of specific amplicons from mastitis-causing pathogens in less than 3 h. Using a similar protocol, we also showed that it was possible to detect specific amplicons from four different mastitis-causing pathogens (six strains) on the same pad. The influence of two different printing buffers, phosphate-buffered saline (pH 7.4) and carbonate buffer (pH 9.6), on the functionality of the primary antibodies was also compared.

Oligosaccharides have been widely recognized for their prebiotic and anti-infective properties. Among the different types of mammalian milk, the one of humans is the richest source of naturally derived oligosaccharides. However, their use as a basis for functional foods is hampered, due to their structural complexity, which in turn makes their re-synthesis extremely difficult. Thus, oligosaccharides from other sources have to be used. In this sense, goat milk constitutes a very appealing candidate, as it contains the highest amount of oligosaccharides among domestic animals, while goat milk oligosaccharides show significant similarities to human milk oligosaccharides from a structural point of view. Studies on goat milk oligosaccharides are scant, and more data is required in order to provide solid clinical evidence of their beneficial effects on humans. The aim of this review is to collect and present the main research findings on goat milk oligosaccharides structure, health effects and isolation.

The aim of this study was to estimate breed differences in milk fatty acid (FA) profile among 5 dairy cattle breeds present in the Netherlands: Holstein-Friesian (HF), Meuse-Rhine-Yssel (MRY), Dutch Friesian (DF), Groningen White Headed (GWH), and Jersey (JER). For this purpose, total fat percentage and detailed FA contents in milk (14 individual FA and 14 groups of FA) predicted from mid-infrared spectra were used. Mid-infrared spectrometry profiles were collected during regular milk recording from a range of herds with different combinations of breeds, including both purebred and crossbred cows. The data set used for the analyses contained 41,404 records from a total of 24,445 cows. In total 7,626 cows were crossbreds belonging to the breeds HF, MRY, DF, GWH, and JER; 1,769 purebreds (≥87.5%) belonging to the breeds MRY, DF, GWH, and JER; and the other 15,050 cows were HF. Breed effects were estimated using a single-trait animal model. The content in milk of short-chain FA C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, and C16:0 was higher for JER and the content in milk of C16:0 was lower for GWH compared with the other breeds; when adjusting for breed differences in fat percentage, however, not all breed differences were significant. Breed differences were also found for cis-9 C14:1, cis-9 C16:1, C18:0, and a number of C18 unsaturated FA. In general, differences in fat composition in milk between HF, MRY, and DF were not significant. Jerseys tended to produce more saturated FA, whereas GWH tended to produce relatively less saturated FA. After adjusting for differences in fat percentage, breed differences in detailed fat composition disappeared or became smaller for several short- and medium-chain FA, whereas for several long-chain unsaturated FA, more significant breed differences were found. This indicates that short- and medium-chain FA are for all breeds more related to total fat percentage than long-chain FA. In conclusion, between breed differences were found in detailed FA composition and content of individual FA. Especially, for FA produced through de novo synthesis (short-chain FA, C12:0, C14:0, and partly C16:0) differences were found for JER and GWH, compared with the breeds HF, MRY, and DF.

Several epidemiologic studies have shown that growing up in a farming environment is associated with a decreased risk of allergies. A factor that correlates strongly with this effect is the early ingestion of unheated cow's milk. Although, to date, no controlled studies on raw milk consumption have been performed to formally demonstrate this effect, several factors in bovine milk have been described that might explain how raw cow's milk consumption can decrease the risk of allergies. In addition, increasing knowledge on the immunologically active factors in breast milk have also contributed to our understanding of the effects of bovine milk in infants because many of the factors in bovine milk are expected to have functional effects in human subjects as well. Here we review these factors and their mechanisms of action and compare their presence in bovine milk and breast milk. A better understanding of these factors, as well as how to retain them, might ultimately lead to the development of mildly processed milk and infant nutrition products that could become a part of preventive strategies to reduce the incidence of allergic disease.

Penicillins are used universally in both human and veterinary medicine. The European Union (EU) has established maximum residue levels (MRLs) for most ss-lactam antibiotics in milk and animal tissues and included them in the National Residue Monitoring Programs. In this study, a novel method is described for the determination and confirmation of eight penicillins in porcine tissues, milk and animal feed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). To prevent degradation of penicillin residues during workup, a derivatisation procedure was developed, by which penicillins were converted to stable piperidine derivatives. Deuterated piperidine derivatives were synthesised for all relevant penicillins, enabling the use of isotope dilution for accurate quantification. Penicillin residues were derivatised in the crude extract with piperidine and isolated using solid-phase extraction. The penicillin piperidine derivatives were determined by LC-MS/MS. The method was validated at the current MRLs, which range from 25-300 microg kg(-1) in muscle and kidney to 4-30 microg kg(-1) in milk as well as at the target value of 100 microg kg(-1) chosen for animal feed, according to the EU requirements for a quantitative confirmatory method. Accuracy ranged from 94-113% (muscle), 83-111% (kidney) and 87-103% (milk) to 88-116% (animal feed). Intra-day precision (relative standard deviation (RSD)(r)) ranged from 5-13% (muscle, n = 18), 4-17% (kidney, n = 7) and 5-18% (milk, n = 7) to 11-32% (animal feed, n = 18). Inter-day precision (RSD(RL), n = 18) ranged from 6-23% (muscle) to 11-36% (animal feed). From the results, it was concluded that the method was fit for purpose at the target MRLs in animal tissue and target levels for animal feed.

The steroid hormone progesterone is the primary biomarker of the reproductive status of female mammals. Current techniques of monitoring progesterone are based predominantly on (enzyme) immunoassays, but these are too expensive to be affordable in daily screening programmes because of their associated labour costs and the need for laboratory facilities and/or equipment. Here, we discuss existing methods as well as new perspectives for (automated) application at point of care/need, e.g. the milking parlour. These make it apparent that a low-cost, fully automated progesterone assay system to monitor the reproductive status is far from being realised at present. Timely ovulation prediction techniques for artificial insemination and reproductive cycling are thus urgently needed, and promising perspectives will be highlighted.

Capillary zone electrophoresis (CZE) was tested for reproducibility and was shown to be a suitable method for estimating the relative concentration of ¿-lactalbumin, ß-lactoglobulin, ¿S2-casein (¿S2-CN), ¿S1-CN, ¿-CN, and ß-CN in milk. This study showed how the method can also be used to determine the relative concentration of two different phosphorylation states of ¿S1-CN (¿S1-CN-8P and ¿S1-CN-9P) and three of ¿S2-CN (¿S2-CN-10P, ¿S2-CN-11P and ¿S2-CN-12P). Furthermore, with CZE it was possible to determine most common genetic variants including the ¿-CN E variant that has not been identified by CZE before. Analyses of milk samples of 1948 Dutch Holstein-Friesian cows showed large variation in both the relative protein concentration and the relative concentration of different phosphorylation states for all milk proteins studied. Correlations between different phosphorylation states of ¿S1- and ¿S2-CN indicated that the relative concentration of specific phosphorylation states of ¿S1- and ¿S2-CN were related to each other.

With regard to human health aspects of milk fat, increasing the amount of unsaturated fatty acids in milk is an important selection objective. The cow's diet has an influence on the degree of unsaturation, but literature suggests that genetics also plays a role. To estimate genetic variation in milk fatty acid unsaturation indices, milk fatty acid composition of 1,933 Dutch Holstein Friesian heifers was measured and unsaturation indices were calculated. An unsaturation index represents the concentration of the unsaturated product proportional to the sum of the unsaturated product and the saturated substrate. Intraherd heritabilities were moderate, ranging from 0.23 +/- 0.07 for conjugated linoleic acid (CLA) index to 0.46 +/- 0.09 for C16 index. We genotyped the cows for the SCD1 A293V and DGAT1 K232A polymorphisms, which are known to alter milk fatty acid composition. Both genes explain part of the genetic variation in unsaturation indices. The SCD1 V allele is associated with lower C10, C12, and C14 indices, and with higher C16, C18, and CLA indices in comparison to the SCD1 A allele, with no differences in total unsaturation index. In comparison to the DGAT1 K allele, the DGAT1 A allele is associated with lower C10, C12, C14, and C16 indices and with higher C18, CLA, and total indices. We conclude that selective breeding can contribute to higher unsaturation indices, and that selective breeding can capitalize on genotypic information of both the SCD1 A293V and the DGAT1 K232A polymorphism.

The aim was to study the effect of pasturing time (4 versus 9 hours) combined with restricted indoor feeding on fat content, fatty acid composition, concentration of ¿-tocopherol, ß-carotene, uric acid and ß-hydroxybutyrate in milk from Holstein Friesian dairy cows. Morning and afternoon milk samples were collected three times at the end of week 2, 4 and 6 of the experiment. Morning and afternoon milk from cows at pasture for 4 h varied significantly in medium and long chain fatty acids (C6-C14), C18:1 n-9, C18:2 n-6, C18:3 n-6 and cis 9, trans 11 CLA concentration for all the 3 weeks. Fat percentage, ¿-tocopherol, ß-carotene, milk uric acid and ß-hydroxybutyrate showed significant differences between morning and afternoon milk from 4-h pasture. In the contrary, there was no significant difference observed between morning and afternoon milk for most parameters studied in the 9-h pasture group. Similarly the difference between morning milk from 4- and 9-h was also non-significant for most parameters. Therefore, in general 4-h morning, 9-h morning and 9-h afternoon milk were very similar in their compositions for the parameters studied.

Mastitis wordt vrijwel altijd veroorzaakt door een infectie met bacteriële ziektekiemen. Virale infecties kunnen ook een rol spelen, maar zijn van ondergeschikt belang. Dit artikel zal daarom alleen ingaan op diagnostisch onderzoek van bacteriele ziektekiemen. Er zijn veel verschillende bacteriën die mastitis kunnen veroorzaken, waaronder Staphylococcus aureus, Escherichia coli, Streptococcus uberis, Streptococcus dysgalactiae en Stroptococcus agalactiae, coagulase negatieve staphylococcen (CNS/STC), Klebsiella spp en Mycloplasma spp. In dit artikel een bespreking van de resultaten van bacteriologisch onderzoek van melk bij GD in 2006

The fatty acid (FA) composition of cows milk has become less favorable to human health in the last four decades due to changed feeding and management practices, notably higher proportions of concentrates and silages in diets with less grazing. Essential FA and conjugated linoleic acid (CLA) concentrations have generally declined and, with more `low-fat¿ dairy products, human intake of these FA has declined even further since ruminant food products are the main source of human CLA intake. Changing societal drivers and consumer demands require dairy production systems that provide food products through sustainable production systems. Milk FA were examined in milk produced in different regions of the world, in the different seasons of the year, and under different feeding systems. FA levels were examined in forages, concentrates and milk. Milk from cows fed fresh green forage, especially those grazing grass, had a much higher unsaturated:saturated FA proportion, with more polyunsaturated FA and more CLA (in particular C18:2 cis-9, trans-11), than milk from silage-fed cows. Farmers from some dairy cooperatives in The Netherlands that produce milk from grazed grass now receive a premium payment in addition to the base milk price, so that primary producers can benefit from the higher market value at the end of the production chain.

Two experiments were conducted to evaluate the effects on milk composition of transition from a fresh grass diet on pasture to a winter diet of mixed grass/maize silage. In trial 1, the change in milk fatty acid profile for six dairy cows in mid-lactation was followed via analysis of milk samples collected from individual cows on days 0, 2, 6 and 14 after the transition of diet. In trial 2, milk of 12 cows was analysed on days 0 and 4 after transition. In trial 1, dry matter intake and milk production did not change during the experiment. After transition, the average milk fat content increased from 43.7 g/kg on day 0 to 54.9 g/kg on day 14 and the milk fatty acid composition altered within two days. The largest changes occurred in the proportions of C 14:0 (from 89 g/kg milk fat on day 0 to 117 g/kg on day 14), C 16:0 (226-348 g/kg), C18:0 (110-88 g/kg) and C18:1 cis-9 (238-170 g/kg). The average content of conjugated linoleic acid (CLA) decreased from 24.3 g/kg milk fat on day 0 to 4.4 g/kg on day 14, while the proportion of the beneficial n-7 fatty acid (FA) rumenic acid declined from 0.95 to 0.85 of total CLA. Vaccenic acid contents decreased linearly with CLA contents. Two days after transition large changes had occurred, whereas the changes between day 6 and day 14 were relatively small. These results were confirmed by the results of trial 2, which also indicated that most changes actually took place within four days after transition. The milk fatty acid profile of grazing cows was more favourable from a consumer health perspective than that of silage-fed cows. (C) 2004 Elsevier B.V. All rights reserved.

Despite its low natural folate concentration, milk is responsible for 10-15% of the daily folate intake in countries with a high dairy consumption. Milk products can be considered as a potential matrix for folate fortification, e.g., with synthetic folic acid, to enhance the daily intake of folate. In untreated milk, the natural folate, 5-methyltetrahydrofolate (5-CH3-H(4)folate), is bound to folate-binding proteins (FBP). In this study, the extent of binding to FBP for folic acid and 5-CH3-H(4)folate was investigated in a dynamic in vitro model simulating human gastric passage. Protein binding of folic acid and 5-CH3-H(4)folate was characterized using gel-exclusion chromatography. Before gastric passage, folic acid and 5-CH3-H(4)folate were bound mainly to FBP (76-79%), whereas 7% was free. Folic acid remained bound to FBP to a similar extent after gastric passage. For 5-CH3-H(4)folate, the FBP-bound fraction gradually decreased from 79 to 5% and the free fraction increased from 7 to 93%. Although folic acid enters the proximal part of the intestine bound to FBP, 5-CH3-H(4)folate appears to be present mainly as free folate in the duodenal lumen. The stability of FBP was similar in both folate/FBP mixtures, i.e., 70% of the initial FBP content was retained after gastric passage. This study indicated that FBP are partly stable during gastric passage but have different binding characteristics for folic acid and 5-CH3-H(4)folate in the duodenal lumen. This could result in different bioavailability from folic acid- and 5-CH3-H(4)folate-fortified milk products.

Casein phosphorylation is a posttranslational modification catalyzed by kinase enzymes that attach phosphate groups to specific AA in the protein sequence. This modification is one of the key factors responsible for the stabilization of calcium phosphate nanoclusters in casein micelles and for the internal structure of the casein micelles. α(S1)-Casein (α(s1)-CN) is of special interest because it constitutes up to 40% of the total casein fraction in milk, and it has 2 common phosphorylation states, with 8 (α(S1)-CN-8P) and 9 (α(S1)-CN-9P) phosphorylated serine residues. Factors affecting this variation in the degree of phosphorylation are not currently known. The objective of this research was to determine the genetic background of α(S1)-CN-8P and α(S1)-CN-9P. The genetic and phenotypic correlation between α(S1)-CN-8P and α(S1)-CN-9P was low (0.18 and 0.19, respectively). This low genetic correlation suggests a different genetic background. These differences were further investigated by means of a genome-wide association study, which showed that both α(S1)-CN-8P and α(S1)-CN-9P were affected by a region on Bos taurus autosome (BTA) 6, but only α(S1)-CN-8P was affected by a region on BTA11 that contains the gene that encodes for β-lactoglobulin (β-LG), and only α(S1)-CN-9P was affected by a region on BTA14 that contains the diacylglycerol acyltransferase 1 (DGAT1) gene. Estimated effects of β-LG protein genotypes showed that only α(S1)-CN-8P was associated with the β-LG A/B polymorphism (g.1772G>A and g.3054C>T); the AA genotype of β-LG was associated with a lower concentration of α(S1)-CN-8P (-0.32% wt/wt) than the BB genotype (+0.41% wt/wt). Estimated effects of DGAT1 K232A genotypes showed that only α(S1)-CN-9P was associated with the DGAT1 gene polymorphism; DGAT1 AA genotype was associated with a higher α(S1)-CN-9P concentration (+0.53% wt/wt) than the DGAT1 KK genotype (-0.44% wt/wt). The results give insight in phosphorylation of α(S1)-CN-8P and α(S1)-CN-9P, which seem to be regulated by a different set of genes.

Thermal processing and Maillard reaction (MR) affect the nutritional and sensorial qualities of milk. In this paper an olive mill wastewater phenolic powder (OMW) was tested as a functional ingredient for inhibiting MR development in ultrahigh-temperature (UHT)-treated milk. OMW was added to milk at 0.1 and 0.05% w/v before UHT treatment, and the concentration of MR products was monitored to verify the effect of OMW phenols in controlling the MR. Results revealed that OMW is able to trap the reactive carbonyl species such as hydroxycarbonyls and dicarbonyls, which in turn led to the increase of Maillard-derived off-flavor development. The effect of OMW on the formation of Amadori products and N-e-(carboxymethyl)-lysine (CML) showed that oxidative cleavage, C2-C6 cyclization, and the consequent reactive carbonyl species formation were also inhibited by OMW. Data indicated that OMW is a functional ingredient able to control the MR and to improve the nutritional and sensorial attributes of milk.

The average casein micelle size varies widely between milk samples of individual cows. The factors that cause this variation in size are not known but could provide more insight into casein micelle structure and into the physiology of casein micelle formation. The objective of this research was therefore to determine factors that influence average casein micelle size in milk from individual cows. Average casein micelle size of milk samples was associated with the A and B genetic variants of k-casein, and differences in concentration of glycosylated k-casein as a fraction of total milk protein. Milk samples with a low average casein micelle size were associated with the B variant of k-casein and a higher relative concentration of glycosylated k-casein, compared with milk samples with a high average casein micelle size. Differences observed may be attributed to the effect of glycosylated k-casein groups on casein micelle formation in the mammary gland.

Buttermilk is a source of interesting nutritional and functional components, e.g. polar lipids and proteins. However, it is still considered as a low-value by-product of the dairy industry with high variations in biochemical composition and bacterial contaminations. The objective of this study was to develop a process based on microfiltration, permitting the removal of microorganisms to ensure the safety of buttermilk components for human nutrition. Industrial buttermilks and the products collected during microfiltration were characterized using particle size measurements, biochemical and microbiological analysis. The combination of homogenization at 80 MPa and cross-flow microfiltration successfully removed bacteria from skimmed buttermilk: bacterial reduction > 4.8 log(10) with 0 cfu/ml in the permeate using the 0.8 mu m pore size membrane and 1 cfu/ml with 1.4 mu m membrane. Chemical analysis revealed the efficient permeation of proteins, total lipids and polar lipids. Polar lipid classes permeated equally the membrane. This work will contribute in improving the safety of buttermilk-based ingredients. Industrial relevance: This work describes the development of an innovative process combining homogenization and cross-flow microfiltration for the selective removal of bacteria from industrial buttermilks. This process is an alternative to heat treatments that alter the nutritional and organoleptic properties of food products. The safety of buttermilk-based ingredients containing milk polar lipids of interest will contribute in their economic valorization for human nutrition. (c) 2013 Elsevier Ltd. All rights reserved.

Whey permeate is a co-product obtained when cheese whey is passed through an ultrafiltration membrane to concentrate whey proteins. Whey proteins are retained by the membrane, whereas the low-molecular weight compounds such as lactose, salts, oligosaccharides and peptides pass through the membrane yielding whey permeate. Research shows that bovine milk from healthy cows contains hundreds of naturally occurring peptides – many of which are homologous with known antimicrobial and immunomodulatory peptides – and nearly 50 oligosaccharide compositions (not including structural isomers). As these endogenous peptides and oligosaccharides have low-molecular weight and whey permeate is currently an under-utilized product stream of the dairy industry, we hypothesized that whey permeate may serve as an inexpensive source of naturally occurring functional peptides and oligosaccharides. Laboratory fractionation of endogenous peptides and oligosaccharides from bovine colostrum sweet whey was expanded to pilot-scale. The membrane fractionation methodology used was similar to the methods commonly used industrially to produce whey protein concentrate and whey permeate. Pilot-scale fractionation was compared to laboratory-scale fractionation with regard to the identified peptides and oligosaccharide compositions. Results were interpreted on the basis of whether industrial whey permeate could eventually serve as a source of functional peptides and oligosaccharides. The majority (96%) of peptide sequences and the majority (96%) of oligosaccharide compositions found in the laboratory-scale process were mirrored in the pilot-scale process. Moreover, the pilot-scale process recovered an additional 33 peptides and 1 oligosaccharide not identified from the laboratory-scale extraction. Both laboratory- and pilot-scale processes yielded peptides deriving primarily from the protein ß-casein. The similarity of the laboratory- and pilot-scale's resulting peptide and oligosaccharide profiles demonstrates that whey permeate can serve as an industrial-scale source of bovine milk peptides and oligosaccharides.

A centripetal temperature gradient takes place in Grana Padano (GP) during moulding because of the slow heat transfer within the cheese and the fast cooling of the outer part. This gradient, in combination with the low pH value, induces a centripetal inactivation of alkaline phosphatase (ALP). Throughout the ripening process, the activity of the enzyme keeps > 3 10(5) mU/kg cheese in the peripheral zones and

Dairy gels (DG), such as yoghurts, contain both solid and liquid fats at the time of consumption, as their temperature rises to anything between 10 and 24 degrees C after being introduced into the mouth at 4 degrees C. The mass ratio between solid and liquid fats, which depends on the temperature, impacts the organoleptic properties of DG. As the ordinary methods for determining this ratio can only be applied to samples consisting mainly in fat materials, a fat extraction step needs to be added into the analytical process when applied to DG, which prevents the study of the potential impact of their colloidal structure on milk fat fusion behavior. In situ quantitative proton nuclear magnetic resonance spectroscopy (isq H-1 NMR) was investigated as a method for direct measurements in DG: at temperatures between 20.0 and 70.0 degrees C, the liquid fat content and the composition of triacylglycerols of the liquid phase (in terms of alkyl chains length) were determined. Spectra of isolated milk fat also enable the quantification of the double bonds of triacylglycerols. Statistical tests showed no significant difference between isolated milk fat and milk fat inside a DG in terms of melting behavior: the fat globule membrane does not seem to have a significant influence on the fat melting behavior.

Since the 1980s, efforts have been made to develop sensors that measure a parameter from an individual cow. The development started with individual cow recognition and was followed by sensors that measure the electrical conductivity of milk and pedometers that measure activity. The aim of this review is to provide a structured overview of the published sensor systems for dairy health management. The development of sensor systems can be described by the following 4 levels: (I) techniques that measure something about the cow (e.g., activity); (II) interpretations that summarize changes in the sensor data (e.g., increase in activity) to produce information about the cow’s status (e.g., estrus); (III) integration of information where sensor information is supplemented with other information (e.g., economic information) to produce advice (e.g., whether to inseminate a cow or not); and (IV) the farmer makes a decision or the sensor system makes the decision autonomously (e.g., the inseminator is called). This review has structured a total of 126 publications describing 139 sensor systems and compared them based on the 4 levels. The publications were published in the Thomson Reuters (formerly ISI) Web of Science database from January 2002 until June 2012 or in the proceedings of 3 conferences on precision (dairy) farming in 2009, 2010, and 2011. Most studies concerned the detection of mastitis (25%), fertility (33%), and locomotion problems (30%), with fewer studies (16%) related to the detection of metabolic problems. Many studies presented sensor systems at levels I and II, but none did so at levels III and IV. Most of the work for mastitis (92%) and fertility (75%) is done at level II. For locomotion (53%) and metabolism (69%), more than half of the work is done at level I. The performance of sensor systems varies based on the choice of gold standards, algorithms, and test sizes (number of farms and cows). Studies on sensor systems for mastitis and estrus have shown that sensor systems are brought to a higher level; however, the need to improve detection performance still exists. Studies on sensor systems for locomotion problems have shown that the search continues for the most appropriate indicators, sensor techniques, and gold standards. Studies on metabolic problems show that it is still unclear which indicator reflects best the metabolic problems that should be detected. No systems with integrated decision support models have been found. Key words: automated

Oligosaccharides have been widely recognized for their prebiotic and anti-infective properties. Among the different types of mammalian milk, the one of humans is the richest source of naturally derived oligosaccharides. However, their use as a basis for functional foods is hampered, due to their structural complexity, which in turn makes their re-synthesis extremely difficult. Thus, oligosaccharides from other sources have to be used. In this sense, goat milk constitutes a very appealing candidate, as it contains the highest amount of oligosaccharides among domestic animals, while goat milk oligosaccharides show significant similarities to human milk oligosaccharides from a structural point of view. Studies on goat milk oligosaccharides are scant, and more data is required in order to provide solid clinical evidence of their beneficial effects on humans. The aim of this review is to collect and present the main research findings on goat milk oligosaccharides structure, health effects and isolation.

In this study, the effect of antibody adsorption on physicochemical properties of Streptococcus sobrinus was studied. Bacteria were preincubated with polyclonal antibodies or with OMVU10, a monoclonal antibody (MAb) reactive with S. sobrinus. The zeta potentials and the hydrophobicity as determined by microbial adhesion to hydrocarbons were measured in potassium phosphate buffer with a pH ranging from 2 to 9, S. sobrinus preincubated with polyclonal antibodies was positively charged at pH 2, 3, and 4 and had an isoelectric point at pH 4.8. Untreated S. sobrinus cells or cells preincubated with MAbs were negatively charged over the whole pH range. X-ray photoelectron spectroscopy showed a decrease in O/C and P/C ratios for bacteria preincubated with polyclonal antibodies. A combination of the pH-dependent zeta potential and the X-ray photoelectron spectroscopy data of the overall chemical composition of the cell surface suggests that polyclonal antibody adsorption occurs through blocking of surface phosphate. The measurement of hydrophobicity by microbial adhesion to hydrocarbons revealed that S. sobrinus preincubated with polyclonal antibodies was hydrophobic (90% of the bacteria bound to hexadecane), whereas the controls were relatively hydrophilic. S. sobrinus preincubated with OMVU10 was found to be more hydrophobic than the controls at pH 5 and 7. Hydrophobicity as measured by water contact angles shelved an increase in hydrophohicity when S. sobrinus was preincubated with polyclonal antibodies. The epitopes to which the antibodies are directed were visualized by immunogold labeling and electron microscopy. The results suggested that OMVU10 is reactive with only a few epitopes of the cell surface, whereas polyclonal antibodies were found to be reactive with many epitopes. In conclusion, adsorption of polyclonal antibodies was found to influence the overall physicochemical surface properties of the organism, probably by forming a coating over the whole cell surface. Adsorption of MAbs was more localized, which could explain their lesser influence on these surface properties.

Chantier qualité GA; Mastitis, an inflammation of the mammary gland, is the most costly infectious disease of dairy ruminants worldwide. Although it receives considerable attention, the early steps of the host response remain poorly defined. Here, we report a noninvasive method using milk fat globules (MFG) as a source of mammary RNA to follow the dynamics of the global transcriptional response of mammary epithelial cells (MEC) during the course of a bacterial infection. We first assessed that RNA isolated from MFG were representative of MEG RNA; we then evaluated whether MFG RNA could be used to monitor the MEG response to infection. Sufficiently high yields of good-quality RNA (RNA integrity numbers ranging between 6.7 and 8.7) were obtained from goat MFG for subsequent analyses. Contamination of MFG by macrophages and neutrophils, which can be trapped during creaming, was assessed and when using quantitative real-time PCR for cell-type specific markers, was shown to be weak enough (

The objective of this study was to characterize the fatty acids (FA) in milk based on genetic and herd parameters to investigate the origin of the different FA in milk. Milk samples of 1912 Dutch Holstein-Friesian cows were analysed for 39 different FA including odd and branched-chain fatty acids. The proportion of variation caused by genetic and herd effects was calculated. In addition, genetic and herd correlations among the fatty acids were estimated and a clustering technique was used to visualise these correlations. The results indicated that in Dutch milk C12:0 is not completely synthesised de novo but also partly blood derived. It was suggested that C20:0 in milk is formed from the action of elongase enzymes on C18:0 and that the odd-chain FA C5:0-C13:0 and a part of C15:0 and C17:0 are synthesised de novo while the other part of C15:0 and C17:0 is blood derived. Furthermore, this work gives an overview of the opportunities to change the concentration of individual FA both by breeding and feeding. It is clearly shown that the extent to which the individual FA can be changed varies greatly and is dependent on the origin of the different FA in milk.