Milk Ca Research Articles

High milk consumption is associated with carotid atherosclerosis in middle and old-aged Chinese

BackgroundCarotid atherosclerosis (CA) can reflect atherosclerotic status of systemic vessels, and is associated with ischemic stroke and cognitive impairment. Milk consumption is growing in China, and data are limited on the association between milk and CA risk. MethodsParticipants aged ≥40 years in China National Stroke Prevention Project were recruited for carotid ultrasound examination, and those with carotid endarterectomy, carotid stenting stroke or coronary heart disease were excluded. Participants were defined as having CA when intima–media thickness (IMT) ≥1 mm or plaques were detected by ultrasonography. For milk consumption, though contents were not analyzed, people were divided into high consumption (≥200 ml/day and ≥5 day/week) and low consumption (occasional or never) groups. Multivariate logistics regression analyses were done in both full and propensity score-matched population to identify the association between milk consumption and CA. Results84880 participants were included in the final analysis. After being adjusted by age, gender, living location, smoking habits, drinking habits, physical activity, obesity, hypertension, diabetes, and dyslipidemia, high milk consumption is associated with CA in both full population (odds ratio [OR] = 1.26, 95% confidence interval [CI] 1.19–1.33) and propensity score-matched population (OR = 1.25, 95%CI 1.17–1.34). High milk consumption is also a risk factor for IMT thickening (OR = 1.15, 95%CI 1.08–1.23), carotid plaque formation (OR = 1.17, 95%CI 1.09–1.25) and carotid stenosis over 50% (OR = 1.52, 95%CI 1.10–2.14) in the propensity score-matched population. ConclusionsHigh milk consumption is related to CA in middle and old-aged Chinese population. More cautious advice on milk intake should be given in this population for prevention of atherosclerosis.

Concentrations of toxic metals and essential elements in raw cow milk from areas with potentially undisturbed and highly disturbed environment in Slovakia.

Dietary composition and husbandry practices largely determine the essential trace element status and the toxic metal exposure of livestock and consequently their concentrations in animal products. The main objective of this study was to determine the real contamination of selected areas of Slovakia compared with existing Environmental regionalization of the Slovak Republic (SR) created by the Ministry of the Environment SR. Another aim of this study was to determine the content of essential and toxic metals in feed and milk of dairy cows on selected farms in Slovakia referred to the suitability of the use of milk from these areas to other food processing. This article deals with the analysis of the content of selected elements in feed and milk of dairy cows in the area of Novoť (Northern Slovakia; area with undisturbed environment) and Čečejovce (Eastern Slovakia; highly disturbed environment). Eleven elements have been analyzed (essential elements: calcium, zinc, magnesium, selenium, iron, copper; toxic elements: arsenic, cadmium, mercury, lead, nickel). Samples of feed and milk were collected five times during the spring season and five times during the autumn season in 2016. Analysis of samples was performed in Eurofins Bel/Novamann (Nové Zámky, Slovak Republic). Analyses were performed by atomic absorption spectroscopy and atomic emission spectrometry. The obtained values of the individual elements in the feed and milk were evaluated by Student's t test. Significantly higher contents of essential elements Ca, Zn, Fe, Mg, and Cu were found in the feed of dairy cows in Čečejovce (P < 0.001). Significantly higher (P < 0.001) As and Ni content in feed in Čečejovce in autumn season was also recorded. However, the content of these elements in feed did not affect their milk content. The content of Ca, Zn, and Mg in milk was significantly (P < 0.001) higher in Novoť in both investigated seasons. Some essential elements and toxic elements in feed and milk were below the LOQ (limit of quantification). Reduced content of Ca and Zn in milk in both farms compared with optimal limits, decreased Ca and Mg content in feed in Novoť, and a significant increase of Ca and Mg in feed in Čečejovce in autumn season were found. It can be concluded, due to the low content of toxic elements on these farms, that the use of milk of dairy cows from these areas for direct use or for dairy product processing is appropriate and poses no health risk to the consumers.

Determination of Trace and Major Elements in Vegan Milk and Oils by ICP-OES After Microwave Digestion.

Increasing technological developments also bring about environmental pollution. Heavy metals and metallic compounds, as a result of soil, water, and air industrialization, pass through to people and animals through the food chain and have a negative impact on health. In this study, the concentrations of Na, Mg, K, Ca, P, Fe, Cu, B, Mn, Zn, Al, S, As, Bi, Cd, Co, Cr, Mo, Ni, Pb, Pt, Sb, Se, Sn, Ti, W, and Hg in commercial vegan milk (soybean milk, coconut milk, and almond milk) and oils (soybean oil, coconut oil, bitter almond oil, sweet almond oil, and walnut oil) were determinated using inductively coupled plasma-optical emission spectrometry after microwave digestion. In order to compare the efficiencies of digestion in vegan milk and oil samples, 6mL of HNO3 (conc.), 3mL of H2O2 (30%); 7mL of HNO3 (conc.), 3.5mL of H2O2 (30%), and 8mL of HNO3 (conc.), 4mL of H2O2 (30%) were used in microwave digestion procedures. The proposed procedures were applied to the analysis of 81 vegan milk and 125 vegan oil samples covering three different brands in Turkey. Na, Mg, K, Ca, P, S, Mn, Zn, Cu, B, Sb, and Sn concentrations in vegan milks ranged (minimum-maximum in ppm) as follows: 307.4-501.2, 1.8-15.6, 478.8-1300.4, 276.3-1189, 197-797.8, 18.7-241.4, 0.09-0.42, 0-0.58, 0.02-1.06, 0.34-1.56, 0.26-0.67, and 3.4-30.4ppm, respectively. The results of Na, K, Ca, P, Mg, S, Mn, Zn, Se, Fe, Cu, Sb, and Sn concentrations in vegan oils (minimum-maximum in ppm) ranged as follows: 6.8-31.2, 403.5-425.2, 142.8-160.4, 71.65-149.8, 0.35-0.85, 14.2-35.2, 0.02-0.27, 0.07-0.36, 1.90-4.64, 0.92-5.36, 0.01-0.05, 1.02-1.66, and 21.2, 35.0ppm, respectively. Vegan milk contents except for Se, Fe, Sb, and Sn in this study were higher than vegan oil contents. The methods were validated by linearity, limits of detection and quantification, precision, and analyzing certified reference material (NIST SRM-3235), soybean milk. The highest values of LOD were found Pb, P, and Bi, and the highest values of LOQ were found Mo, Pb, and Sb.

Phosphorus and zinc are less bioaccessible in soy-based beverages in comparison to bovine milk

Abstract Total contents and bioaccessible fractions of Ca, K, Mg, Na, P and Zn in bovine milk and soy-based were determined to investigate if this plant-based beverage could be an adequate substitute of bovine milk with relation to the ingestion of these essential elements. The quantification of the elements was made by inductively coupled plasma optical emission spectrometry (ICP OES) and their bioaccessibilities were evaluated by in vitro simulation of the human gastrointestinal digestion. Total contents of minerals were similar among the milk samples, whereas the concentrations determined in soy-based beverages exhibited more variability, mainly for Ca, P and Zn. All the evaluated elements presented bioaccessible fractions higher than 60% in bovine milk, whereas in the soy-based beverages bioaccessibilities lower than 30% were obtained for P and Zn. Special attention should be given for P and Zn intake in cases of substitution of bovine milk by soy-based beverages.

Effect of calcium intake and the dietary cation-anion difference during early lactation on the bone mobilization dynamics throughout lactation in dairy cows.

This study investigated the consequences of a low supply of dietary Ca with or without a low dietary cation-anion difference (DCAD) during early lactation on bone mobilization and reconstitution during lactation and on the dynamics of milk Ca content. Fifteen multiparous Holstein cows were distributed among 3 treatments 5 weeks before their expected calving date. These treatments differed based on the provision of diets through the first 10 weeks of lactation. During this period, the control treatment (NCa) consisted of a diet providing 100% of the Ca requirement, with a DCAD of 200 mEq/kg dry matter (DM). The LCa (low Ca) and LCaLD (low Ca, low DCAD) treatments consisted of diets providing 70% of the Ca requirement, with a DCAD of 200 and 0 mEq/kg DM, respectively. After 10 weeks, all cows received the same total mixed ration, which was formulated to meet 100% of the Ca requirement. LCa and LCaLD tended to decrease the body retention of Ca at 3 weeks of lactation compared with NCa but affected neither the dynamics of the blood biomarkers of bone formation and resorption during lactation nor the body retention of Ca at 17 weeks of lactation. Cows almost entirely compensated for the decrease in Ca supply caused by LCa and LCaLD by increasing their apparent digestive absorption of Ca at 3 weeks of lactation, whereas their apparent digestive absorption was unaffected by the treatments at 17 weeks of lactation. Milk production tended to be lower throughout lactation with LCa and LCaLD compared with NCa, with a mean difference of 2 kg/d. The results of this study also indicated that measuring the dynamics of milk Ca content during lactation cannot be considered effective for indirectly estimating the dynamics of bone mobilization in cows. The results also suggested that limited Ca intake at the beginning of lactation may have deleterious effects on milk production.

Serotonin regulates maternal calcium homeostasis during the perinatal period of sheep.

The goal of this experiment was to demonstrate the ability of an infusion of serotonin (5-HT; 5-hydroxytryptamine) precursors to increase 5-HT production during the transition from pregnancy to lactation and its effects on gene expression related to calcium (Ca) transporters in the mammary gland and bone resorption markers in the femur. Thirty pregnant Bamei mutton sheep were randomly assigned to 3 experimental groups. All groups received a daily intravenous infusion of saline (control group; n = 10), saline containing 0.178 mg of L-tryptophan/kg body weight (BW) (TRP group, n = 10) or 0.178 mg of 5-hydroxytryptophan/kg BW (5-HTP group, n = 10), beginning on day 7 of prepartum and continuing until delivery. Serum (pre- and postpartum), milk (postpartum), and femur and mammary gland tissue (day 9) were collected. Sheep infused with 5-HTP had a larger total serum Ca concentration on days 3, 6, 15, and 30 of lactation and total milk Ca concentration on days 3, 6, 12, and 15 of lactation compared with that of the control group. Sheep infused with 5-HTP and TRP increased blood and milk concentrations of 5-HT on days 3, 6, 9, and 30 of lactation and parathyroid hormone-related protein (PTHrP) on day 3 of prepartum and on days 3, 6, and 15 of lactation (P < 0.05). In addition, compared to that of the control group, the TRP or 5-HTP infusion upregulated PTHrP, a sodium/calcium exchanger, plasma membrane Ca2+ ATPase 2, secretory pathway Ca2+ ATPase 1, and calcium sensing receptor mRNA expression in mammary gland and receptor-activated nuclear factor kappa-B ligand mRNA expression in the femur, but had no effect on receptor-activated nuclear factor kappa-B and osteoprotegerin mRNA expression in the femur (P < 0.05). This suggests that 5-HT and PTHrP may be involved in regulating maternal Ca homeostasis during the transition from pregnancy to lactation in the sheep.

Mineral Elements in the Raw Milk of Several Dairy Farms in the Province of Alberta.

The objective of this study was to determine the concentrations of 20 minerals in the whole raw milk from Holstein dairy cows in the province of Alberta, Canada. A total of 156 milk samples were collected from 26 dairy farms (n = 6 per farm) and analyzed with inductively coupled plasma mass spectrometry (ICP-MS) for five macrominerals (Ca, Mg, P, K, and Na), ten microminerals (Bo, Co, Cu, Fe, Mn, Mo, Ru, Se, St, and Zn), and five heavy metals (Al, As, Cd, Cr, and Pb). Calculated means were compared with their recommended daily intakes (RDIs) or minimal risk levels (MRLs) obtained from several food safety agencies and with data obtained from a world meta-analytical study we conducted previously. Results of the present study showed differences in the concentrations of multiple minerals between the Alberta farms involved and world averages (WA) and within Alberta farms. Concentrations of macrominerals, including Ca, Mg, P, K, and Na, in the raw milk were greater in Alberta dairy farms than the WA (p < 00.5; except Ca). Of note, concentrations of Ca showed the highest variability among Alberta farms, with 11 farms having lower milk Ca than WA. The other macrominerals were higher than WA in more than 88% of Alberta farms. Data demonstrated that concentrations of microminerals, including Co, Cu, Fe, Mn, and Mo, in Alberta raw milk were lower compared with WA (p < 0.05). Selenium was the only element in raw milk that was found to have higher concentrations in all farms in Alberta vs. WA. High variability was observed for B, Sr, and Zn, which were lower in multiple locations around the province. Concentrations of heavy metals in the Alberta raw milk, including Al, As, Cd, and Pb, were lower than WA, whereas concentrations of Cr were higher. Most importantly, all heavy metals were below their respective MRLs in all analyzed samples. Overall, data from this study showed that raw milk from Holstein dairy cows in Alberta has concentrations of most mineral elements below their MRLs and some of them different from WA. Of note, although concentrations of Se and Zn in the raw milk were higher in Alberta compared with WA, their concentrations were still below their respective MRLs.

Mineral and Citrate Concentrations in Milk Are Affected by Seasons, Stage of Lactation and Management Practices

This study was conducted to examine associations between nutrition, time of year and season of calving on milk mineral concentrations in 24 pasture-based dairy farms. There was substantial variation in the concentrations (mean with range in parentheses) of Ca 1072 (864–1310) mg/kg; citrate 1579 (880–2080) mg/kg; P 885 (640–1040) mg/kg; Mg 98 (73–122) mg/kg; Na 347 (248–554) mg/kg; K 1534 (1250–2010) mg/kg; and S 295 (155–372) mg/kg with most of the variation associated with stage of lactation, although the influence of days in milk was different for different minerals. Feeding practices were also important in determining the concentrations of some components. Milk Ca, citrate, P, and K concentrations were greater (p &lt; 0.05) in cows receiving mineral supplements, while Ca, P and Mg were positively correlated (p &lt; 0.05) with the amount of concentrates fed. Milk citrate and K concentrations were positively correlated (p &lt; 0.05) with herbage allowance. Milk Se (15 (&lt;3–37) µg/kg) and Zn (3.4 (2.2–4.9) mg/kg) also varied with time of year, with Se concentrations also greater (13.7 vs 11.6 µg/kg) in spring compared with autumn calving herds and positively correlated (p &lt; 0.05) with the amount of concentrates fed and mineral supplementation. These data indicate that calving pattern and feeding practices could be used to reduce variation in the measured milk mineral concentrations.

Effects of dietary Zeolite supplementation on milk yield and composition and blood minerals status in lactating dairy cows

ABSTRACT The purpose of this study was to determine effects of inclusion of Zeolite in lactating dairy cows’ rations on blood Ca, P, and Mg status during periparturient period, as well as on milk yield and composition during early lactation. Forty-two pregnant dry Holstein cows were randomly assigned as Zeolite treated cows (EG) or untreated cows (CG) comprising 21 cows each. The EG group received the same diet as the CG group, but with addition of 200 g/cow/day of Zeolite. There was no treatment effect on milk total solids, milk fat, milk protein, lactose, milk ash, milk Ca, milk P, milk Mg, plasma P, and plasma Mg for CG and EG. Conversely, milk yield, fat corrected milk (FCM), fat yield, protein yield, lactose yield, and plasma Ca were significantly increased by Zeolite addition. These results indicate that Zeolite can be effectively used in the rations of dry and lactating cows with positive effects on milk production and components yields and no deleterious effects on milk composition or blood parameters. Blood Ca was enhanced around calving and at the beginning of lactation. It is suggested that prepartum Zeolite supplementation may alleviate the negative Ca balance and therefore reduce the incidence of subclinical hypocalcaemia during the periparturient period.

Spectrophotometric Determination of Calcium with 1-(2-Pyridylazo)-2-Napthol Sensitized By Tween 80 Application to Various Samples

Spectrophotometric method for determination of Ca in aqueous solution using 1-(2-pyridylazo)-2-naphthol (PAN) as colour reagent has been developed. The method was based on the formation of Ca-PAN complex at pH 12 and measuring absorbance at 550nm, with molar absorptivity of 1.70×104 L.mol−1cm-1, average recovery is 101.72 and precision (RSD) is better than ±2.8% indicating that the method is relatively sensitive, accurate and precise. The binary system of Ca(PAN)2 and conditional stability constant of 1.467x1010 L2.mol−2 adherence of Beer’s law over concentration range 0.08-2ppm. The method was applied for the determination of Ca in natural water, milk, yogurt, human serum, grip and tomato juice satisfactory. In presence of 1% tween 80 and composite masking agents of pH 11.5 the absorbance measurements were made at 540nm giving molar absorptivity of 2.7×104 L.mol−1 cm−1, average recovery of 101.2 and precision (RSD) better than ±3% indicating that the Ca(PAN)2 system is sensitive, accurate, and precise. In addition it is considered to be simple, rapid and do not need heating or solvent extraction steps, moreover it can be applied successfully for the assay of Ca in various samples over concentration range of 0.0008-0.8ppm.

Effect of calcium and magnesium supplementation on minerals profile, immune responses, and energy profile of ewes and their lambs

The effect of maternal supplementation of calcium (Ca) and magnesium (Mg) during late gestation and early lactation on immune function of offspring are unknown. The vital role of Ca and Mg on immune function is well known. This study investigated the effect of Ca and Mg supplementation to ewes through late gestation and early lactation on the plasma mineral concentration, immune response and energy profile of ewes, and their offspring.Forty eight ewes were allocated between four treatment groups, namely: Ca, Mg, Ca + Mg and control. Ewes in Ca, Mg and Ca + Mg treatments were supplemented with 50 g calcium carbonate (lime), 50 g magnesium oxide (Causmag) and 25 g calcium carbonate + 25 g magnesium oxide, respectively, from 12 ± 4 days before gestation to one month after lambing. Blood and urine samples were collected from ewes at 2 weeks prior to the commencement of lambing (−2 weeks), 12 h post lambing (+12 h), 2 weeks post lambing (+2 weeks) and 4 weeks post lambing (+4 weeks). Colostrum/milk samples from ewes and blood samples from lambs were collected at +12 h, +2 weeks, and +4 weeks.Lambs born out of ewes in the Ca and Ca + Mg treatments had higher oxidative burst response and total antioxidant capacity (TAC) compared to the Mg and control groups. Oxidative burst response and IgG production in lambs improved from birth to at 4 weeks of age, while the TAC was highest at 2 weeks of age. Ewes supplemented with Ca, Mg and Ca + Mg regulated energy balance more efficiently at lambing compared to the control group. Supplementation of ewes with Mg supplements increased milk Ca level at 4 weeks post lambing and supplementation of ewes with Mg supplements increased plasma Mg concentration in the Mg group over time.Overall, these results indicate that supplementation of ewes with Ca and Ca + Mg during late gestation and early lactation improved immune response in their lambs at least in part via changes in oxidative burst response and antioxidant capacity. Mineral supplementation had a beneficial effect on energy balance regulation in ewes at lambing.

Genetic parameters for cheese-making properties and milk composition predicted from mid-infrared spectra in a large data set of Montbéliarde cows

Cheese-making properties of pressed cooked cheeses (PCC) and soft cheeses (SC) were predicted from mid-infrared (MIR) spectra. The traits that were best predicted by MIR spectra (as determined by comparison with reference measurements) were 3 measures of laboratory cheese yield, 5 coagulation traits, and 1 acidification trait for PCC (initial pH; pH0PPC). Coefficients of determination of these traits ranged between 0.54 and 0.89. These 9 traits as well as milk composition traits (fatty acid, protein, mineral, lactose, and citrate content) were then predicted from 1,100,238 MIR spectra from 126,873 primiparous Montbéliarde cows. Using this data set, we estimated the corresponding genetic parameters of these traits by REML procedures. A univariate or bivariate repeatability animal model was used that included the fixed effects of herd × test day × spectrometer, stage of lactation, and year × month of calving as well as the random additive genetic, permanent environmental, and residual effects. Heritability estimates varied between 0.37 and 0.48 for the 9 cheese-making property traits analyzed. Coagulation traits were the ones with the highest heritability (0.42 to 0.48), whereas cheese yields and pH0 PPC had the lowest heritability (0.37 to 0.39). Strong favorable genetic correlations, with absolute values between 0.64 and 0.97, were found between different measures of cheese yield, between coagulation traits, between cheese yields and coagulation traits, and between coagulation traits measured for PCC and SC. In contrast, the genetic correlations between milk pH0 PPC and CY or coagulation traits were weak (-0.08 to 0.09). The genetic relationships between cheese-making property traits and milk composition were moderate to high. In particular, high levels of proteins, fatty acids, Ca, P, and Mg in milk were associated with better cheese yields and improved coagulation. Proteins in milk were strongly genetically correlated with coagulation traits and, to a lesser extent, with cheese yields, whereas fatty acids in milk were more genetically correlated with cheese yields than with coagulation traits. This study, carried out on a large scale in Montbéliarde cows, shows that MIR predictions of cheese yields and milk coagulation properties are sufficiently accurate to be used for genetic analyses. Cheese-making traits, as predicted from MIR spectra, are moderately heritable and could be integrated into breeding objectives without additional phenotyping cost, thus creating an opportunity for efficient improvement via selection.

Characterization of the nongenetic causes of variation in the calcium content of bovine milk on French farms

Milk is an important source of Ca in Western diets. Milk Ca is important for the cheesemaking process and could be a useful biomarker of Ca regulation in cows. The objective of this study was to identify and quantify nongenetic factors affecting the variation of Ca content in bovine milk. During the PhénoFinLait program, a survey was performed in 3 major areas of milk production in France. This survey consisted of collecting milk samples, together with information about herd management and cow nutrition, from 924 commercial farms. More than 200,000 individual milk samples were collected, and Ca content was measured by mid-infrared spectroscopy. Each farm was surveyed several times during the year, and 3 to 6 milk samples were collected from each cow. An equation to predict milk Ca content from mid-infrared spectra was developed based on the Ca contents of 292 milk samples, and the milk Ca contents of the 200,000 samples were then predicted. Milk Ca content was lowest in Holstein cows, intermediate in Montbéliarde cows, and highest in Normande cows. For all 3 breeds, milk Ca decreased during the first month of lactation and increased after the fourth month of lactation, with the range between minimum and maximum values largest in Holsteins, intermediate in Montbéliardes, and smallest in Normandes. Milk Ca content also decreased with parity in all 3 breeds. By using multiple factorial analysis, 6 major feeding strategies employed on French dairy farms were characterized based on the data from the survey. Calendar month and cow feeding strategy affected milk Ca content, which dropped in the spring during grazing turnout and was lower when cows were fed fresh and conserved grass rather than corn silage. In conclusion, environmental factors induce variations in milk Ca content in addition to the genetics of the cows, which to date have been identified as a main factor of variation of milk Ca content in dairy cows. In several of the tested conditions, increases in milk production and in the amount of Ca daily secreted in milk were associated with a decrease in milk Ca content as though the mammary gland operated to limit the exportation of Ca when milk production rapidly increased. This result would suggest that milk Ca content could be a biomarker of Ca regulation in dairy cows.

SOME STUDIES ON MILK PRODUCTION AND ITS COMPOSITION IN MAGHREBI SHE-CAMEL UNDER FARMING AND TRADITIONAL PASTORAL SYSTEMS IN EGYPT

This study aimed to determine the effect of management systems (farming and traditional pastoral system) and parity order on milk yield and composition from lactating Maghrebian she-camel in addition to its effects on somatic cell count and bacterial infection of subclinical mastitis. Total of forty lactating she-camels (camelus dromedarius) (aging 5–12 years, weighing 370-590 kg, between the first and eighth parities) were divided into two system groups (farming and pastoral, 20 in each). Each of farming or pastoral group was divided into four sub groups according to their parity, including 1-2,3-4,5-6 and 7-8 parities ,5 animals in each. Over all mean of IgG, IgM and IgA concentrations did not differ significantly (P<0.05) under both management systems. Concentration of IgG and IgA increased (P<0.05), while IgM insignificantly increased by advancing parity. Effect of interaction between management system and parity of immunoglobulin concentrations was not significant. Daily or total milk yield was higher (P<0.001) under farming more than pastoral system by about 20.70 and 11.75%, respectively. Fat, protein, lactose, total solids, and solid non fat contents attained significantly higher values in milk of farming than in pastoral system. However, ash content showed an opposite (P<0.001) trend. Daily and total milk yield and its composition significantly increased by advancing parity .The interaction between management system and parity was not significant on milk yield and milk compositions. For somatic cells count the ratio was highly significant (P<0.05) in the traditional pastoral system than that recorded in farming system for collected milk samples from subclinically mastitic she-camels. Under pastoral system milk showed significantly higher contents of Na and K and significantly lower P and Mg than farm system. Milk Ca and chlorine contents were not affected by management system. By advancing animal parity, Ca and P contents increased (P<0.05), up to 7-8 parities, while Na and K increased (P<0.05), 5-6 and 3-4 parities respectively. Yet, Mg and chlorine contents were not affected significantly by parity. The interaction between management system and parity was highly significant (P<0.001) only on K and P, reflecting different trend of change in K and P contents in camels under farm and pastoral system by advancing parity. The levels of mineral contents subsequently increased with advanced ages in both systems. Our bacteriological study results revealed that S.aureus (2% and 6%), CNS (5% and 2%), E.coli (8% and 2%), S.agalactia (1% and 2%) and other Strept. (10% and 3%) were the main single bacterial isolates from all studied milk samples in both groups: traditional pastoral system and farming system respectively .Total bacterial isolates in single bacterial infections were significantly different in both systems of management (26% and 15%) respectively. Also investigations illustrated that CNS +E.coli, S.aureus + E.coli, S.aureus + other Strept., S.aureus + E.coli + other Strept. and S.aureus+ CNS+ other Strept. were the main groups of mixed bacterial isolates in percentages of (7% and 2%), (6% and 4%), (7% and 5%), (6% and 3%) and (6% and 5%) respectively, with significant different in total mixed bacterial isolates (32% and 19%) in both traditional pastoral system and farm system respectively. There was a direct relationship between the frequency of sub-clinical mastitis and the calving number. The study could be recommended to increase awareness of the nomads about the importance of the effect of feeding system and parity in addition to bacterial isolates on yield and nutritive value of camel milk produce for human consumption or suckling their newborns.

Effect of dietary difructose anhydride III supplementation on bone mineral density and calcium metabolism in late-lactation dairy cows.

The aim of the present study was to examine the effect of 28 days of dietary difructose anhydride (DFA) III supplementation on calcium (Ca) metabolism in late-lactation dairy cows. Twenty-four multiparous pregnant Holstein cows were divided into two groups. The DFA group was fed total mixed ration (TMR) supplemented with 40 g of DFA III, and the control group was fed TMR only. The replenishment of bone Ca reserves was evaluated by measuring bone mineral density (BMD) and blood biochemical bone markers. Serum Ca concentrations, urinary Ca-to-creatinine (Cre) (Ca/Cre) ratios, and milk Ca concentrations were also analyzed. The BMD of the 4th caudal vertebra in the DFA group was higher than in the control group on day 28. With respect to bone markers, the ratios of undercarboxylated osteocalcin (ucOC) to osteocalcin (OC) in the DFA group were significantly lower than those in the control group on days 21 and 28. Milk Ca concentrations in the DFA group were also higher than those in the control group on days 14, 21, and 28, whereas serum Ca concentrations and urinary Ca/Cre ratios were unchanged in both groups. These results suggest that dietary supplementation with DFA III increased BMD and decreased serum ucOC/OC ratios in late-lactation dairy cows; this indicates that the replenishment of bone Ca reserves may be enhanced by dietary DFA III supplementation.

Phenotypic characterisation of major mineral composition predicted by mid-infrared spectroscopy in cow milk

Population-level phenotyping is, for some traits, hardly achievable due to limitation of reference analyses. Mid-infrared spectroscopy (MIRS) is a quick and cost-effective laboratory technique allowing the prediction of innovative milk quality features on a large scale. The present study aimed at investigating factors associated with milk Ca, K, Mg, Na and P contents predicted by MIRS models on a large multi-breed spectral data set of 123,240 test-day records. Two dairy (Holstein–Friesian and Brown Swiss) and two dual-purpose (Simmental and Alpine Grey) cattle breeds were considered. Sources of variation of predicted milk mineral contents were studied using linear mixed models, including the fixed effects of breed, month of sampling, stage of lactation, parity and interactions between the main effects. Random factors were herd nested within breed, cow nested within breed and the residual. Calcium content was greater in milk of dual-purpose than dairy cattle breeds. Simmental cows produced milk with the greatest content of Ca and Na, and milk of Holstein-Friesian had the lowest P content. Variation of content of Ca, Mg, Na and P throughout lactations exhibited an opposite trend to that of milk yield, with the lowest values around the peak of lactation. On the other hand, K content mirrored the trend of milk yield. Multiparous cows had lower content of milk minerals, with the exception of Na, compared with first parity animals. Environmental factors identified in the present study can be considered for within-breed genetic evaluation to adjust records of milk mineral contents for these effects.

Influence of Processing and Fermentation on Concentrations of Zn, Ca, Mg, and Phosphate in Goat Milk

The aim of this study was to determine the influence of the manufacturing and fermentation process on the mineral composition of different types of goat milk and fermented products. Zn, Ca, Mg, and P concentrations were determined in 47 samples of raw, commercial, and commercial fermented goat milk from Southern Spain. Significantly higher P and Mg levels and significantly lower Zn levels were found in the raw goat milk than in the processed samples. P and Zn levels did not differ among the commercial fermented goat milks, which use different species of fermenting bacteria. Commercial fermented goat milk produced with species of probiotic starter bacteria increased Zn and Ca levels. This is one of first studies to report the influence of processing and fermentation on levels of Zn, Ca, Mg, and P in goat milk. These data should be considered in the estimation of daily dietary intakes of these elements.

Investigation of macro, micro and toxic element concentrations of milk and fermented milks products by using an inductively coupled plasma optical emission spectrometer, to improve food safety in Turkey

In this study, the quantification of macro, micro and toxic elements in milk and its products was carried out using inductively coupled plasma optical emission spectrometry (ICP-OES) after using sample preparation procedures (wet digestion, dry digestion, and microwave digestion). Samples were collected from farms and markets in Edirne, Turkey. Ca, Mg, Na, K, Cu, Fe, Mn, Zn, Al, and Ba concentrations in the farm milk and its products ranged from 823 to 1499, 109–476, 218–1498, 905–1694, 0.094–0.26, 2.0–3.7, 0.014–0.105, 1.2–5.2, 0.192–0.35 and 0.075–0.191mgkg−1 respectively. The results in commercial milk and milk based products (minimum-maximum in mg·kg−1) were: Ca 791–1518, Mg 107–518, Na 221–1594, K 901–1692, Cu 0.068–0.23, Fe 2.2–4, Mn 0.019–0.087, Zn 2–5, Al 0.124–0.40 and 0.080–0.197. Macro, micro and toxic element contents of the commercial milk and its products in this study generally were higher than that of the natural samples. However, a tolerable daily diet of these elements by the Trakya region is well below the Turkish Food Codex (TFC) levels of macro, micro and toxic elements.

Use of human milk in the assessment of toxic metal exposure and essential element status in breastfeeding women and their infants in coastal Croatia

Pregnant and lactating women and infants are vulnerable population groups for adverse effects of toxic metals due to their high nutritional needs and the resultant increased gastrointestinal absorption of both, essential and toxic elements. Although breastfeeding is recommended for infants worldwide, as human milk is the best source of nutrients and other required bioactive factors, it is also a pathway of maternal excretion of toxic substances including toxic metals and thus a source of infant exposure. The aim of this research was to assess health risks in breastfeeding women in the coastal area of the Republic of Croatia and their infants (N=107) due to maternal exposure to Cd and Pb via cigarette smoking, and Hg via seafood and dental amalgam fillings, and their interaction with essential elements. Biological markers of exposure were the concentrations of main toxic metals Pb, Cd and Hg in maternal blood and three types of breast milk throughout lactation stages. Biological markers of effects were the levels of essential elements Ca, Fe, Cu, Zn and Se in maternal serum and breast milk. With regard to cigarette smoking as a source of exposure to Cd and Pb, there were effects of smoking on Cd concentration in blood and correlations between the smoking index and Cd concentrations in maternal blood (Ͽ=0.593; P<0.001) and mature milk (Ͽ=0.271; P=0.011) and Pb concentration in transitional milk (Ͽ=0.280; P=0.042). Regarding fish, we found correlations between weekly consumption frequency and total Hg concentrations in maternal blood (Ͽ=0.292; P=0.003) and mature milk (Ͽ=0.303; P=0.003). The number of dental amalgam fillings correlated with total Hg concentrations in colostrum (Ͽ=0.489; P=0.005) and transitional milk (Ͽ=0.309; P=0.018). As for the essential element status, only Se levels in maternal serum decreased by 10% in persons who continued smoking during pregnancy compared to non-smokers. In conclusion, the levels of main toxic metals Cd, Pb and Hg and essential elements Ca, Fe, Cu, Zn and Se in maternal blood and three types of breast milk samples in the studied area of coastal Croatia showed no risk of disrupted essential element levels with regard of toxic metal exposure in both breastfeeding women and their infants.

Dietary cation-anion difference and day length have an effect on milk calcium content and bone accretion of dairy cows

Milk and dairy products are an important source of Ca for humans. Recent studies have shown fluctuations in cow milk Ca content during the year in France, with high values in winter and with corn silage diets, and a decrease during May and June and with grass diets. The aim of this study was to identify the reasons for this seasonal decrease in milk Ca content by testing the effect of 2 levels of dietary cation-anion differences (DCAD; 0mEq/kg of dry matter for DCAD 0 and 400mEq/kg for DCAD 400) and 2 day lengths (8h of light/d for short days: SD; and 16h/d for long days: LD) on the Ca balances of dairy cows. The DCAD treatments were designed to mimic diets based either on corn silage or on herbage. The cows were only illuminated by solarium lights providing UVA and UVB. The trial was conducted according to 2 simultaneous replicates of a 4×4 Latin square design using 8 dairy cows averaging 103±44 d in milk with 4 periods of 14d. Data were analyzed by ANOVA with a model including treatment, cow, and period effects. No significant interaction was found between day length and DCAD treatments. With DCAD 400 compared with DCAD 0, blood pH increased and plasma ionized Ca content decreased, whereas the plasma total Ca content did not differ between treatments. Milk Ca content, however, increased with DCAD 400 compared with DCAD 0, in relation to a decrease in the amount of Ca excreted in urine. The DCAD had no significant effect on protein and casein contents and DCAD 400 tended to decrease milk yield. This illustrates that the udder did not decrease Ca uptake from the blood at high DCAD even though DCAD 400 decreased the mammary availability of Ca by decreasing the proportion of blood ionized Ca. Milk Ca and casein contents were significantly lower with LD compared with SD, whereas day length had no effect on milk yield after 14d of treatment. Bone accretion of cows increased when the Ca content of milk increased (i.e., with DCAD 400 compared with DCAD 0 and with SD compared with LD). This work suggests that long and sunny days could explain part of the seasonal decrease in milk Ca content in summer and refutes the hypothesis that low milk Ca contents at grazing could be due to the high DCAD of herbage.