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1.
Iron (Fe) and zinc’s (Zn) interaction at the absorptive level can have an effect on the success of co-fortification of wheat flour with both minerals on iron deficiency prevention. The aim of the study was to determine the effect of increasing levels of zinc fortificant on the iron absorption of bread co-fortified with iron and zinc consumed with a black tea. Twelve women aged 33–42 years participated in the study. They received on four different days 200 mL of black tea and 100 g of bread made with wheat flour (70 % extraction) fortified with either 30 mg Fe/kg alone, as ferrous sulfate (A), or with the same Fe-fortified flour, but with graded levels of Zn, as zinc sulfate: 30 mg/kg (B), 60 mg/kg (C), or 90 mg/kg (D). Fe radioisotopes (59Fe and 55Fe) of high specific activity were used as tracers, and Fe absorption iron was measured by the incorporation of radioactive Fe into erythrocytes. The geometric mean and range of ±1 SD of Fe absorption were as follows: A?=?6.5 % (2.2–19.3 %), B?=?4.6 % (1.0–21.0 %), C?=?2.1 % (0.9–4.9 %), and D?=?2.2 % (0.7–6.6 %), respectively; ANOVA for repeated measures F?=?10.9, p?<?0.001 (Scheffè’s post hoc test: A vs. C, A vs. D, B vs. C, and B vs. D; p?<?0.05). We can conclude that Fe absorption of bread made from low-extraction flour fortified with 30 mg/kg of Fe, as ferrous sulfate, and co-fortified with zinc, as zinc sulfate consumed with black tea is significantly decreased at a zinc fortification level of ≥60 mg/kg flour.  相似文献   

2.
The cofortification of milk with iron (Fe) and zinc (Zn) is a strategy used to prevent these deficiencies during childhood. Given that Zn can negatively interact with iron in aqueous solutions, the objective of the present study was to determine the effect of Zn on Fe absorption of milk fortified with Fe and Zn. Twenty-eight women between 33 and 47?years of age, with contraception and a negative pregnancy test, participated in one of two absorption studies. They received on four different days, after an overnight fast, 200?mL of milk (26?% fat) fortified with 10?mg Fe/L, as (A) ferrous sulfate, or the same milk but with graded doses of added Zn, as Zn sulfate of (B) 5, (C) 10, and (D) 20?mg/L (study 1, n?=?15). In study 2 (n?=?13), subjects received the same milk formulations, but these were also fortified with ascorbic acid (70?mg/L). Milk was labeled with radioisotopes 59Fe or 55Fe, and the absorption of iron was measured by erythrocyte incorporation of radioactive Fe. The geometric mean and range of ±1 SD of Fe absorption in study 1 were as follows: formula A?=?6.0?% (2.8?C13.0?%); B?=?6.7?% (3.3?C13.6?%); C?=?5.4?% (2.2?C13.2?%); and D?=?5.2?% (2.8?C10.0?%) (ANOVA for repeated measures, not significant). For study 2, data are as follows: 8.2?% (3.6?C18.7?%); B?=?6.4?% (2.5?C16.4?%); C?=?7.7?% (3.2?C18.9?%); and D?=?5.2 (1.8?C14.8?%) (ANOVA for repeated measures, not significant). In conclusion, according to the results from this study, it appears that the addition of zinc up to 20?mg/L does not significantly inhibit iron absorption from milk fortified with 10?mg/L of iron.  相似文献   

3.
Helicobacter pylori infection could impair iron absorption from fortified products. The objective of the study was to determine the effect of H. pylori infection on iron absorption from asymptomatic adults consuming wheat flour fortified with iron and zinc. The (13)C urea breath test was used to assess H. pylori infection. Twenty-four H. pylori-positive and 26 H. pylori-negative volunteers completed the study. On day?1, the subjects were randomized to receive for breakfast bread fortified with either ferrous sulfate and zinc sulfate or ferrous fumarate and zinc oxide. Bread fortified with ferrous sulfate was labeled with (59)Fe as sulfate, and bread fortified with ferrous fumarate was labeled with (55)Fe as fumarate. On day?3, they received the other type of bread, with the respective tracers. On days?18-23, a proton pump inhibitor was administered to all subjects. On day?24, all subjects received bread fortified with ferrous fumarate and zinc oxide labeled with (55)Fe as fumarate. H. pylori prevalence was 77.6%. The geometric mean (±1?SD) of iron absorption was significantly higher for ferrous sulfate than fumarate (6.9?±?2.9% vs. 0.5?±?3.5%, p?相似文献   

4.
An experiment was conducted using a total of 840, 1-day-old, Arbor Acres commercial male broilers to compare copper (Cu) sulfate and tribasic Cu chloride (TBCC, Cu2(OH)3Cl) as sources of supplemental Cu for broilers fed in floor pens. Chicks were randomly allotted to one of seven treatments for six replicate pens of 20 birds each, and were fed a basal corn–soybean meal diet (10.20 mg/kg Cu) supplemented with 0, 100, 150, or 200 mg/kg Cu from either Cu sulfate or TBCC for 21 days. Chicks fed 200 mg/kg Cu as TBCC had a higher (P?<?0.05) average daily gain (ADG) than those consuming other diets. Liver Cu contents of broilers fed diets supplemented with TBCC were numerically lower (P?>?0.05) than those of broilers fed diets supplemented with Cu sulfate. The vitamin E contents and the phytase activities in the feed fortified with TBCC were higher (P?<?0.01) and numerically higher (P?>?0.05) compared with those in the feeds fortified with Cu sulfate stored at room temperature, respectively. The vitamin E contents in liver and plasma of broilers fed diets supplemented with TBCC were higher (P?<?0.05) than those of birds fed diets supplemented with Cu sulfate. This result indicates that TBCC is more effective than Cu sulfate in improving the growth of broilers fed in floor pens, and it is chemically less active than Cu sulfate in promoting the undesirable oxidation of vitamin E in feeds.  相似文献   

5.
The study was conducted to determine the effects of iron glycine chelate (Fe-Gly) on growth, tissue mineral concentrations, fecal mineral excretion, and liver antioxidant enzyme activities in broilers. A total of 360 1-day-old commercial broilers (Ross?×?Ross) were randomly allotted to six dietary treatments with six replications of ten chicks per replicate. Broilers were fed a control diet with no Fe supplementation, while five other treatments consisted of 40, 80, 120, and 160?mg Fe/kg diets from Fe-Gly, and 160?mg Fe/kg from ferrous sulfate, respectively. After a 42-day feeding trial, the results showed that 120 and 160?mg Fe/kg as Fe-Gly improved the average daily gain (P?<?0.05) and average daily feed intake (P?<?0.05) of broilers (4?C6?weeks). Addition with 120 and 160?mg Fe/kg from Fe-Gly and 160?mg Fe/kg from FeSO4 increased Fe concentration in serum (P?<?0.05), liver (P?<?0.05), breast muscle (P?<?0.05), tibia (P?<?0.05), and feces (P?<?0.01) at 21 and 42?days. There were linear responses to the addition of Fe-Gly from 0 to 160?mg/kg Fe on Fe concentration in serum (21?days, P?=?0.005; 42?days, P?=?0.001), liver (P?=?0.001), breast muscle (P?=?0.001), tibia (P?=?0.001), and feces (21?days, P?=?0.011; 42?days, P?=?0.032). Liver Cu/Zn superoxide dismutase activities of chicks were increased by the addition of 80, 120, and 160?mg Fe/kg as Fe-Gly to diets at 42?days. There were no differences in liver catalase activities of chicks among the treatments (P?>?0.05). This study indicates that addition with Fe-Gly could improve growth performance and iron tissue storage and improves the antioxidant status of broiler chickens.  相似文献   

6.
Genc  Y.  McDonald  G.K. 《Plant and Soil》2004,262(1-2):23-32
Synthetic hexaploid wheats (Triticum aestivum L) derived from crosses between durum wheat [Triticum turgidum ssp. durum (Desf.) Husn.] and diploid wheat (Aegilops tauschii Coss.) have been developed as a means of transferring desirable characteristics of Aegilops tauschii Coss. such as disease resistance and abiotic stress tolerance into modern bread wheat genotypes. In a growth room experiment using soil culture, we studied a group of 30 synthetic hexaploid wheat accessions together with modern wheat genotypes in order to identify new sources of zinc efficiency for further improvement of zinc efficiency in modern wheat genotypes. There was considerable genetic variation in expression of zinc deficiency symptoms (slight to severe), zinc efficiency (70–100%), shoot Zn concentration (5.8–10.5 and 33–53 mg/kg DW under deficient and sufficient Zn, respectively), shoot Zn content (3.8–10.6 and 34.0–64.6 μg/plant, under deficient and sufficient Zn, respectively) and Zn utilization (0.096–0.172 and 0.019-0.033 g DW/μg Zn under deficient and sufficient Zn, respectively) within synthetic accessions. The presence of synthetic accessions with greater zinc efficiency (100%) than zinc efficient modern wheat genotypes (85%) indicates that the synthetic hexaploids can be used to improve current levels of zinc efficiency in modern wheat genotypes. Synthetic hexaploids may also be a good source of high grain Zn concentration (28–66 mg Zn/kg seed DW).  相似文献   

7.
Currently, the biofortification of crops like wheat with micronutrients such as iron (Fe) and zinc (Zn) is extremely important due to the deficiencies of these micronutrients in the human diet and in soils. Agronomic biofortification with Fe and Zn can be done through different exogenous strategies such as soil application, foliar spraying, and seed priming. However, the excess of these micronutrients can be detrimental to the plants. Therefore, in the last decade, a high number of studies focused on the evaluation of their phytotoxic effects to define the best strategies for biofortification of bread wheat. In this study, we investigated the effects of seed priming with different dosages (1 mg L?1 to 8 mg L?1) of Fe and/or Zn in germination, mitosis and yield of bread wheat cv. ‘Jordão’ when compared with control. Overall, our results showed that: micronutrient dosages higher than 4 mg L?1 negatively affect the germination; Fe and/or Zn concentrations higher than 2 mg L?1 significantly decrease the mitotic index and increase the percentage of dividing cells with anomalies; treatments performed with 8 mg L?1 of Fe and/or 8 mg L?1 Zn caused negative effects in germination, mitosis and grain yield. Moreover, seed priming with 2 mg L?1 Fe?+?2 mg L?1 Zn has been shown to be non-cytotoxic, ensuring a high rate of germination (80%) and normal dividing cells (90%) as well as improving tillering and grain yield. This work revealed that seed priming with Fe and Zn micronutrients constitutes a useful and alternative approach for the agronomic biofortification of bread wheat.  相似文献   

8.
Pharmacological dietary zinc (Zn) concentrations of 1,000 to 3,000 mg/kg diet from Zn oxide have been found to increase growth in post-weaning pigs. However, results were inconsistent among studies. A frequentist meta-analysis, in which effects were numerically described with standardized effect sizes (Hedges's g), was conducted in order to identify and quantify the responses in average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G/F) in post-weaning pigs upon dietary Zn supplementation from Zn oxide. The inability of independent continuous variables to explain significant heterogeneity obtained with fixed effect models necessitated the use of random effects models to calculate summary statistics. Dietary Zn supplementation increased (P?<?0.05) ADG (mean effect size?=?1.086, 95 % confidence intervals?=?0.905–1.266, 26 studies, 72 comparisons), ADFI (mean effect size?=?0.794, 95 % confidence intervals?=?0.616–0.971, 25 studies, 71 comparisons), and G/F (mean effect size?=?0.566, 95 % confidence intervals?=?0.422–0.710, 24 studies, 70 comparisons). Zinc oxide provided a feasible alternative to in-feed antibiotics to improve growth in post-weaning pigs, and its reduction in diets due to potential environmental pollution will have to be negated by alternative feed additives and management strategies in order to prevent economic losses.  相似文献   

9.
We studied the impact of a food supplementation program (Plan Más Vida (PMV)) on the micronutrient nutritional condition of pregnant women from low-income families 1 year after its implementation. The food program provided supplementary diet (wheat and maize—fortified flour, rice or sugar, and fortified soup). We performed a prospective, nonexperimental, cross-sectional study in the province of Buenos Aires, Argentina, evaluating pregnant women at baseline (n?=?164) and 1 year after PMV implementation (n?=?108). Biochemical tests (hemogram, ferritin, vitamin A, zinc, and folic acid), anthropometric assessments (weight and height), and dietary surveys (24 h recall) were performed at the two study points. One year after PMV implementation, no significant changes in anthropometric values were observed. Folic acid deficiency and the risk of vitamin A deficiency (retinol, 20–30 μg/dl) decreased significantly (35.8 to 6.1 % and 64 to 41 %, respectively; p?<?0.000). Anemia and prevalence of iron and zinc deficiency values did not change. Diet survey results showed that although nutrient intake increased significantly, it was still below recommendations. Implementation of the PMV and of the government nutritional strategies had a high impact on the prevalence of folic acid deficiency. We also observed a decrease in the risk of vitamin A deficiency, and no impact on iron and zinc nutritional status. Adherence to the specific fortified food (soup) was not good and intra-family dilution and distribution of food was high.  相似文献   

10.
Micronutrient malnutrition, and particularly deficiency in zinc (Zn) and iron (Fe), afflicts over three billion people worldwide, and nearly half of the world’s cereal-growing area is affected by soil Zn deficiency. Wild emmer wheat [Triticum turgidum ssp. dicoccoides (Körn.) Thell.], the progenitor of domesticated durum wheat and bread wheat, offers a valuable source of economically important genetic diversity including grain mineral concentrations. Twenty two wild emmer wheat accessions, representing a wide range of drought resistance capacity, as well as two durum wheat cultivars were examined under two contrasting irrigation regimes (well-watered control and water-limited), for grain yield, total biomass production and grain Zn, Fe and protein concentrations. The wild emmer accessions exhibited high genetic diversity for yield and grain Zn, Fe and protein concentrations under both irrigation regimes, with a considerable potential for improvement of the cultivated wheat. Grain Zn, Fe and protein concentrations were positively correlated with one another. Although irrigation regime significantly affected ranking of genotypes, a few wild emmer accessions were identified for their advantage over durum wheat, having consistently higher grain Zn (e.g., 125 mg kg?1), Fe (85 mg kg?1) and protein (250 g kg?1) concentrations and high yield capacity. Plants grown from seeds originated from both irrigation regimes were also examined for Zn efficiency (Zn deficiency tolerance) on a Zn-deficient calcareous soil. Zinc efficiency, expressed as the ratio of shoot dry matter production under Zn deficiency to Zn fertilization, showed large genetic variation among the genotypes tested. The source of seeds from maternal plants grown under both irrigation regimes had very little effect on Zn efficiency. Several wild emmer accessions revealed combination of high Zn efficiency and drought stress resistance. The results indicate high genetic potential of wild emmer wheat to improve grain Zn, Fe and protein concentrations, Zn deficiency tolerance and drought resistance in cultivated wheat.  相似文献   

11.
The purpose of the study was to determine the concentration of serum trace and other essential elements of generalized anxiety disorder patients and to find out the relationship between element levels and nutritional status or socioeconomic factors. The study was conducted among 50 generalized anxiety disorder patients and 51 healthy volunteers. Patients were selected and recruited in the study with the help of a clinical psychologist by random sampling. The concentrations of serum trace elements (Zn, Cu, Mn, and Fe) and other two essential elements (Ca and Mg) were determined by graphite furnace and flame atomic absorption spectroscopy. Data were analyzed by independent t test, Pearson’s correlation analysis, regression analysis, and analysis of variance. The serum concentrations of Zn, Cu, Mn, Fe, Ca, and Mg in generalized anxiety disorder patients were 1.069?±?0.40, 1.738?±?0.544, 1.374?±?0.750, 3.203?±?2.065, 108.65?±?54.455, and 21?±?4.055 mg/L, while those were 1.292?±?0.621, 0.972?±?0.427, 0.704?±?0.527, 1.605?±?1.1855, 101.849?±?17.713, and 21.521?±?3.659 mg/L in control subjects. Significantly decreased (p?<?0.05) serum Zn concentration was found in the patient group compared to the control group while serum level of Cu, Mn, and Fe was significantly (p?<?0.05) higher, but the differences of the concentration of Ca and Mg between the patient and control groups were not significant (p?>?0.05). Socioeconomic data revealed that most of the patients were in the lower middle class group and middle-aged. Mean BMI of the control group (23.63?±?3.91 kg/m2) and the patient group (23.62?±?3.77 kg/m2) was within the normal range (18.5–25.0 kg/m2). The data obtained from different interelement relations in the generalized anxiety disorder patients and control group strongly suggest that there is a disturbance in the element homeostasis. So changes in the serum trace element level in generalized anxiety disorder patients occur independently and they may provide a prognostic tool for the diagnosis and treatment of this disease.  相似文献   

12.
An experiment was conducted to investigate the effects of zinc glycinate (Zn-Gly) supplementation as an alternative for zinc sulphate (ZnSO4) on productive and reproductive performance, zinc (Zn) concentration and antioxidant status in broiler breeders. Six hundred 39-week-old Lingnan Yellow broiler breeders were randomly assigned to 6 groups consisting of 4 replicates with 25 birds each. Breeders were fed a basal diet (control group, 24 mg Zn/kg diet), basal diet supplemented with 80 mg Zn/kg diet from ZnSO4 or basal diet supplemented with 20, 40, 60 and 80 mg Zn/kg diet from Zn-Gly. The experiment lasted for 8 weeks after a 4-week pre-test with the basal diet, respectively. Results showed that Zn supplementation, regardless of sources, improved (P?<?0.05) the feed conversion ratio (kilogram of feed/kilogram of egg) and decreased broken egg rate, and elevated (P?<?0.05) the qualified chick rate. Compared with the ZnSO4 group, the 80 mg Zn/kg Zn-Gly group significantly increased (P?<?0.05) average egg weight, fertility, hatchability and qualified chick rate, whereas it decreased (P?<?0.05) broken egg rate. The Zn concentrations in liver and muscle were significantly higher (P?<?0.05) in 80 mg Zn/kg Zn-Gly group than that in ZnSO4 group. Compared with ZnSO4 group, 80 mg Zn/kg Zn-Gly group significantly elevated (P?<?0.05) the mRNA abundances of metallothionein (MT) and copper-zinc superoxide (Cu-Zn SOD), as well as the Cu-Zn SOD activity and MT concentration in liver. Moreover, the 80 mg Zn/kg Zn-Gly group had higher (P?<?0.05) serum T-SOD and Cu-Zn SOD activities than that in the ZnSO4 group. This study indicated that supplementation of Zn in basal diet improved productive and reproductive performance, Zn concentration and antioxidant status in broiler breeders, and the 80 mg Zn/kg from Zn-Gly was the optimum choice for broiler breeders compared with other levels of Zn from Zn-Gly and 80 mg/kg Zn from ZnSO4.  相似文献   

13.
Saccharomyces cerevisiae LN-17 was selected from 26 kinds of primary yeast strains that belong to different genera and species. The iron- and zinc-enriched capability of strain LN-17 was higher than the others. The highest iron and zinc contents of the strain were obtained when the strain grew up under the following conditions: The strain was incubated (5%, v/v) in 50 mL wort medium (pH 6.0) with 100 mg/L Fe ion and 120 mg/L Zn ion. The medium was loaded into a 250-mL Erlenmeyer flask and shaken in a rotary shaker (200 rpm) at 30°C for 60 h. Ferrous sulfate and zinc sulfate were chosen as the source of Fe and Zn. The Fe and Zn contents of the dry cells were determined by atomic absorption spectrum analysis. Under the optimized cultivation conditions, the Fe and Zn contents reached 7.854 mg/g dry cells and 4.976 mg/g dry cells.  相似文献   

14.
Mechanisms for the onset of diabetes and the development of diabetic complications remain under extensive investigations. One of these mechanisms is abnormal homeostasis of metals, as either deficiency or excess of metals, can contribute to certain diabetic outcomes. Therefore, this paper will report the blood levels of chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), mercury (Hg), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn) in subjects with type 1 diabetes (n?=?192, mean age 48.8 years, mean disease duration 20.6 years), type 2 diabetes (n?=?68, mean age 68.4 years, mean disease duration 10.2 years), and in control subjects (n?=?59, mean age 57.2 years), and discuss the results indicating their possible role in diabetes. The metal concentrations were measured by sector field inductively coupled plasma mass spectrometry after microwave-induced acid digestion of blood samples. The accuracy was checked using a blood-based certified reference material, and recoveries of all elements were in the range of 92–101 % of certified values. Type 1 diabetes was found to be associated with Cr (p?=?0.02), Mn (p?<?0.001), Ni (p?<?0.001), Pb (p?=?0.02), and Zn (p?<?0.001) deficiency, and type 2 diabetes with Cr (p?=?0.014), Mn (p?<?0.001), and Ni (p?<?0.001) deficiency. These deficiencies were appreciated also subdividing the understudied patients for gender and age groups. Furthermore, in type 1 diabetes, there was a positive correlation between Pb and age (p?<?0.001, ρ?=?0.400) and Pb and BMI (p?<?0.001, ρ?=?0.309), while a negative correlation between Fe and age (p?=?0.002, ρ?=??0.218). In type 2 diabetes, there was a negative correlation between Fe and age (p?=?0.017, ρ?=??0.294) and Fe and BMI (p?=?0.026, ρ?=??0.301). Thus, these elements may play a role in both forms of diabetes and combined mineral supplementations could have beneficial effects.  相似文献   

15.
The levels of essential (Ca, Mg, Mn, Fe, Zn, Cr, Cu, and Co) and non-essential (Cd and Pb) metal in six different varieties of Ethiopian khat (Catha edulis Forsk, an evergreen stimulant plant) commonly consumed in the country and exported to the neighboring countries were determined by flame atomic absorption spectrometry. Known weight of oven-dried khat samples were wet-digested using 2 mL of (69–72%) HNO3 and 2 mL of (70%) HClO4 for 2 h and 30 min at variable temperature (120–270°C). The mineral contents in the digests were analyzed using flame atomic absorption spectrometer. The following concentrations ranges in fresh-weight basis were recorded in decreasing order: Ca (1,038–2,173 µg/g)?>?Mg (478.2–812.3 µg/g)?>?Fe (53.95–82.83 µg/g)?>?Zn (5.18–9.40 µg/g)?>?Mn (6.98–8.66 µg/g)?>?Cu (1.85–5.53 µg/g)?>?Cr (0.66–3.47 µg/g)?>?Co (0.41–0.80 µg/g). A wide variation in the mineral contents of khat from different region of Ethiopia was noticed. The toxic metals (Pb and Cd) were not detected in all the samples analyzed.  相似文献   

16.
A growth chamber study was conducted to evaluate the effect of application of phosphate fertilizer on soil solution dynamics of cadmium (Cd) and Cd accumulation in durum wheat (Triticum turgidum L. var. durum). Treatments consisted of three phosphate fertilizer sources containing 3.4, 75.2, and 232 mg Cd kg?1 applied at three rates (20, 40 and 80 mg P kg?1) plus a no fertilization control. An unplanted treatment at 40 mg P kg?1 was included to separate the effects on soil solution Cd dynamics of the crop from that of the fertilizer. Soil solution samples were obtained using soil moisture samplers every 10 days after germination. The experimental results indicated that plant biomass significantly increased with P application rates and decreased with increased Cd concentration in the phosphate fertilizers. Total cadmium concentration in soil solution was not consistently affected by phosphate fertilization rate and fertilizer sources, and therefore Cd concentration in the fertilizer. Application of phosphate fertilizer, however, increased the concentration and accumulation of Cd and shoot Cd/Zn ratio, and decreased shoot Zn concentration in durum wheat. Phosphate sources had a marginally significant effect (P?=?0.05) on shoot Cd concentration and did not affect Cd accumulation in durum wheat. Concentration of Cd in soil solution was unrelated to Cd concentration in durum wheat. These results suggest that the immediate increase in Cd concentration and Cd accumulation in durum wheat with phosphate application is due more to competition between Zn and Cd for absorption into plants, enhanced root to shoot translocation and enhanced root development, than to a direct addition effect from Cd contained in phosphate fertilizer. In the short term, application of phosphate fertilizers can increase Cd concentration in the crops, regardless of the Cd concentration of the fertilizer. An optimal P fertilization, possibly in combination with Zn application, may offer an important strategy for decreasing Cd concentration and accumulation in crops.  相似文献   

17.
Two experiments were conducted to examine the effect of zinc (Zn) source on the performance, Zn status, immune response, and rumen fermentation of lactating cows to find the most available Zn source for dairy production. In Experiment 1, a total of 30 multiparous Holstein cows were randomly allocated by body weight and milk yield to one of five treatments in a completely randomized design. Cows were fed a total mixed ration (TMR) with no Zn addition (containing 37.60 mg?Zn/kg TMR by analysis), and the basal TMR supplemented with 40 mg?Zn/kg TMR from either Zn sulfate or one of three organic Zn chelates with weak (Zn-AA W), moderate (Zn-Pro M), or strong (Zn-Pro S) chelation strengths, respectively for 55 days. In Experiment 2, the in vitro rumen fermentation method was used in a completely randomized design involving a 4?×?3 factorial arrangement of treatments. The four Zn sources were the same as those used in Experiment 1, and the three supplemental Zn levels in the rumen fluid were 0, 10, and 20 μg/mL, respectively. The feed intake, milk composition, and somatic cell count (SCC) were unaffected (P?>?0.05) by treatments. However, the milk yield was increased (P?<?0.05) by addition of Zn from both the Zn-AA W and Zn-Pro S. Plasma Zn level at the end of the experiment was increased (P?<?0.05) by addition of Zn from all three organic sources. Serum antibody titers on day 21 after vaccination with foot and mouth disease (FMD) vaccine were increased (P?<?0.05) by both supplemental Zn-AA W and Zn-Pro S. The organic Zn sources with different chelation strengths supplemented at the added Zn level of 10 μg/mL were more effective (P?<?0.05) in improving the rumen fermentation than Zn sulfate, with the most effective being Zn-AA W. In conclusion, Zn source had no influence on the feed intake, milk composition, and SCC; however, both the Zn-AA W and Zn-Pro S were more effective than Zn-Pro M and Zn sulfate in enhancing the rumen fermentation, Zn status, and humoral immune response as well as improving milk yield of lactating cows. The improved milk production might be attributed to the improved rumen fermentation, Zn status, and immune function.  相似文献   

18.
The present study was carried out to determine the accumulation and variation of trace elements in roots and leaves of Asparagus racemosus collected from four different altitudes in Uttarakhand, India, by atomic absorption spectroscopy. The metals investigated were Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li. The concentration level of Fe was found to be highest at an altitude of 2,250 m, whereas the level of Cu was lowest. The maximum concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li were found to be 165.0?±?3.2, 34.0?±?0.5, 84.0?±?0.7, 2,040.0?±?0.3, 122.0?±?1.5, 745.0?±?0.3, 13,260.0?±?3.5, 6,153.0?±?1.6, and 58.0?±?3.8 mg/kg, respectively.  相似文献   

19.
Although a 40 % absorption of a standard reference dose corresponds to iron (Fe) absorption in borderline Fe-deficient subjects, this percentage is currently applied to all subjects independent of Fe status: (a) to assess the use of the 40 % of Fe absorption of the reference dose (FeRD%) for subjects with iron-depleted stores (IDS), normal Fe status (NIS), Fe deficiency without anemia (IDWA), and Fe deficiency anemia (IDA) and (b) to explore relationships between Fe status biomarkers and FeRD%. Six hundred forty-six participants (582 women and 64 men) were selected from multiple Fe bioavailability studies and classified into four groups based on Fe status: NIS, IDS, IDWA, and IDA. All men were classified as normal. The absorption from FeRD% was calculated in each group and correlated with Fe status biomarkers. (a) Women with IDS absorbed 40 (18.9–84.7)?% of the reference dose; (b) for male subjects with NIS, the absorption of the reference dose was 19 (9.8–36.1)?%, while for females, absorption was observed as to be 34 (16.7–68.6)%. In the case of subjects with IDWA, a 43 (19.7–92.5)?% absorption was observed, while subjects with IDA demonstrated 67 (45.2–98.6)?% absorption. Serum ferritin (SF) had the strongest inverse correlation with FeRD% (r?=??0.41, p?<?0.001). A transferrin saturation (TS) <15 % increases the probability that the FeRD% will be highly elevated (OR, 5.05; 95 % CI, 2.73, 9.31; p?<?0.001). A 40 % absorption as reference dose is only appropriate to assess Fe absorption in subjects with IDS and IDWA. SF had an inverse correlation with FeRD%, and TS increases the probability that the FeRD% will be elevated by over fivefold.  相似文献   

20.
An experiment was conducted to determine the effect of dietary copper (Cu) on mineral profile, hematological parameters, and lipid metabolism in lambs. Eighteen Zandi male lambs (approximately 3 months of age; 17.53?±?1.6 kg of body weight) were housed in individual pens and were assigned randomly to one of three treatments. Treatments consisted of (1) control (no supplemental Cu), (2) 10 mg Cu/kg dry matter (DM) from copper sulfate (CuS), and (3) 10 mg Cu/kg DM from Cu proteinate (CuP). The Cu concentration was 8.2 mg/kg DM in the basal diet. Blood was sampled from the jugular vein at the beginning of the study (enrollment, before feeding Cu supplement) and at days 25, 50, and 70 of experiment. The amounts of total serum glucose, urea nitrogen, calcium, phosphorus, iron, copper, zinc, and lipids and hematological parameters were measured. Average daily gain and feed efficiency were improved (P?<?0.05) with Cu supplementation and were better for the lambs fed diet supplemented with CuP. The concentrations of serum Ca, P, and Zn were not affected by source of Cu in the diet. However, Fe concentration was lower (P?<?0.01) in the Cu-supplemented groups. Experimental treatment had no significant effects on the hematological parameters. The serum glucose concentration was not affected by treatments. However, the urea nitrogen concentrations were significantly affected (P?<?0.05) by added Cu and was lower for CuP group as compared to the lambs in the CuS and control groups. Addition of Cu had no influence (P?>?0.05) on the serum triglyceride concentration, but lambs fed with CuP supplement had lower (P?<?0.05) serum cholesterol than the CuS and control animals. These results indicated that CuP supplemented at 10 mg/kg DM improved gain and enhanced the efficiency of nitrogen in male lambs.  相似文献   

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