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1.
The combined effects of vitamin E and selenium were studied in native Anatolian horses subject to strenuous exercise. The concentrations of copper, zinc, iron, calcium, potassium, and magnesium were determined in serum by atomic absorption spectrometry in two study groups (n = 25 each), one of which served as untreated controls. After exercising the horses by running 1,500 m in about 7 min, only the copper level and the copper/zinc ratio significantly increased (p < 0.05), but the concentrations of calcium, potassium, iron, and magnesium remained unchanged. In horses treated with vitamin E and selenium, the calcium and potassium levels decreased to levels lower than those of untreated controls before and after exercise. The iron levels were not changed by exercise or treatment alone but increased when the horses had been supplemented and exercised. The copper level and the copper/zinc ration increased as a result of exercise in both treated and untreated horses. These changes suggest that supplementation with vitamin E and selenium had an important effect on the serum concentrations of calcium, potassium, copper, iron, and the copper/zinc ratio.  相似文献   

2.
The purpose of this study was to quantify the concentrations of crude protein, fat, ash, neutral detergent fiber, acid detergent fiber, lignin, nonstructural carbohydrates, and gross energy in plant foods consumed by wild black and white ruffed lemurs (Varecia variegata). Calcium, phosphorous, magnesium, potassium, sodium, iron, zinc, copper, manganese, molybdenum, and selenium concentrations were also determined. A total of 122 samples from 33 plant families and more than 60 species were collected and analyzed for their nutritional content. The specific nutrient needs of black and white ruffed lemurs are unknown, but quantifying the nutritional composition of the foods they consume in the wild will help nutritionists and veterinarians formulate more appropriate diets for captive ruffed lemurs. This information will also supply information on how man‐induced habitat changes affect the nutritional composition of foods consumed by free‐ranging lemurs. Zoo Biol 29:375–396, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

3.
Primate diets may be influenced by the phytochemical composition of potential food resources. This study examined the protein, fiber, and mineral content of leaves from plant species used as food resources by the proboscis monkey (Nasalis larvatus) in Tanjung Puting National Park, Kalimantan Tengah, Indonesia. In addition, leaf samples were collected from nonfood resources based upon relative density in previously established vegetation plots. Higher concentrations of crude protein, phosphorus, potassium, and zinc were found in young leaves. Mature leaves had higher levels of magnesium, manganese and calcium compared to young leaves. Leaves from species used as food resources were significantly higher in protein (9.9% vs. 8.5%) and lower in fiber (30.5% vs. 40.0% acid detergent fiber) than the leaves from species not used as food sources. Food resources also contained higher concentrations of phosphorus and potassium; nonfood resources contained higher concentrations of calcium and manganese. Proboscis monkeys appear to follow the typical colobine trend: a diet relatively high in protein and low in digestion inhibitors (fiber). Little previous work has examined mineral content as a selection factor in primate food choices. Leaves from species used as food resources contained less calcium (0.35%), iron (34 mg/kg) and phosphorus (0.15%) than dietary standards established for captive nonhuman primates, but values were similar to those established for ruminant herbivores. Other mineral concentrations (potassium, magnesium, manganese, sodium, and zinc) met or exceeded recommended levels for both primates and ruminants. Comparison of diverse nutrients in native diets may provide insight into suitability of domestic animals models for providing adequate diets in captive feeding situations, as well as help define resource limitations in natural environments. Am. J. Primatol. 41:117–128, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

4.
Zinc nutritional status in obese children and adolescents   总被引:4,自引:0,他引:4  
Studies in animals and humans have corroborated that zinc (Zn) metabolism is altered in obesity. The present work intends to evaluate the Zn nutritional status in obese children and adolescents by the determination of some biochemical parameters and analyses of the diets. The investigation was carried out in a group of obese children and adolescents (n=23) and compared to a control group (n=21), both between 7 and 14 yr of age. A software analyzed diet information from 3-d food records. Body composition was evaluated by body mass index, bioelectrical impedance, and skinfold measurements. Zinc nutritional status was evaluated by Zn determination in plasma, erythrocyte, and 24-h urine, by atomic absorption spectrophotometry (γ=213.9 nm). Diets consumed by both groups had marginal concentrations of zinc. Zinc concentrations in plasma and erythrocytes were significantly lower in the obese group. Urinary zinc excretion was significantly higher in the same group. The results allowed one to conclude that zinc nutritional status in obese individuals is altered.  相似文献   

5.
Domestic animals in the elucidation of zinc's role in nutrition   总被引:1,自引:0,他引:1  
Parakeratosis in swine, a disease that caused severe economic losses in many commercial herds during the late 1940's and early 1950's, was caused by an inadequate intake of zinc. In addition to poor growth, the disease involves primarily the epidermal layer of the skin, which in severe cases becomes thickened and heavily encrusted. Finally, deep fissures develop in the encrusted areas. The low availability of zinc in plant protein sources and the increasing use of soybean meal in practical-type diets during the late 1940's contributed to the increasing incidence of the disease. Excessive levels of calcium also increased the incidence and severity of the disease. Prominent features of zinc deficiency in poultry were failure of normal development of long bones and the occurrence of severe lesions on the feet and legs. As with the pig, the low bioavailability of zinc from plant protein sources led to the observation that practical-type diets were limiting in this metal. Although parakeratosis can be produced in cattle fed diets low in zinc, it does not seem to have been a major nutritional problem in ruminants.  相似文献   

6.
Meals of 12 diets were prepared from conventional foods with precautions against contamination by metallic elements because of epidemiologic associations between ischemic heart disease and the metabolism of magnesium, calcium, copper, and zinc. Magnesium, calcium, copper, and zinc were measured by atomic absorption spectrometry with satisfactory accuracy and precision. The mean daily amount of copper in the diets was less than the apparent adult requirement. Mean amounts of magnesium and zinc were close to apparent requirements; however, adults consuming amounts less than one standard deviation below these means may be depleting body stores and be at risk of pathology. Magnesium and copper were highly correlated (r=0.849,P=0.0001) in meals. This and other significant correlations probably will prevent the relationships of these elements to ischemic heart disease from being elucidated by epidemiology. Metabolic experiments will be necessary to differentiate among several hypotheses.  相似文献   

7.
8.
It is generally believed that the zinc metalloenzyme alkaline phosphatase is required to hydrolyze phosphorylated forms of vitamin B-6 prior to their use. To test this hypothesis, rats were fed a liquid diet containing either adequate or moderately low zinc during gestation and lactation. Zinc deficiency was produced in dams evidenced by significant reductions in zinc concentration of plasma (49%), liver (25%), and femur (24%), and plasma alkaline phosphatase activity (48%). Plasma pyridoxal-5′-phosphate (PLP), which significantly increased (61%) in these same rats, was negatively correlated (r=−0.74,P<0.02) with plasma alkaline phosphatase activity. Maternal liver PLP concentration was unaffected by zinc status. The zinc and vitamin B-6 relationship seen in dams was less observable in offspring. Stimulation of erythrocyte alanine aminotransferase activity by exogenously added PLP in vitro tended to be higher in both moderately zinc-deficient mothers and their offspring, but the difference was not significant. Our results support the hypothesis that alkaline phosphatase activity is required for the hydrolysis of plasma PLP. Our results also suggest that zinc status as alkaline phosphatase activity should be defined in an individual if plasma PLP is to be used as an indicator of vitamin B-6 status.  相似文献   

9.
Mark D. Finke 《Zoo biology》2003,22(2):147-162
A variety of commercially raised insects are fed to insectivorous reptiles, but information concerning appropriate diets used to feed these insects is limited. In the present study, house crickets (Acheta domesticus adults and nymphs), mealworms (Tenebrio molitor larvae), and silkworms (Bombyx mori larvae) were fed diets containing graded levels of calcium (Ca) and/or vitamin A–nutrients that are low or absent in most insects. Diets and insects were analyzed for moisture, Ca, phosphorus (P), and vitamin A. For adult crickets and cricket nymphs, body Ca and vitamin A concentrations increased in a linear fashion with increasing levels of dietary Ca or vitamin A. Ca concentrations of silkworms also increased in a linear fashion with increasing levels of dietary Ca. For mealworms, body Ca and vitamin A concentrations increased in a nonlinear fashion with increasing levels of dietary Ca or vitamin A. These regression equations, in conjunction with insect nutrient composition, allow for the calculation of the optimum nutrient concentration for gut‐loading diets. Final recommendations were based on National Research Council (NRC) requirements for rats, adjustments for the energy content of the insects, and nutrient overages as appropriate. Gut‐loading diets for crickets (adults and nymphs) should be supplemented to contain the following nutrients, respectively: Ca (51 and 32 g/kg), vitamin A (8,310 and 5,270 µg retinol/kg), vitamin D (300 and 190 µg cholecalciferol/kg), vitamin E (140 and 140 mg RRR‐α‐tocopherol/kg), thiamin (31 and 21 mg/kg), and pyridoxine (20 and 10 mg/kg). Gut‐loading diets for mealworms should be supplemented to contain the following nutrients: Ca (90 g/kg), iron (51 mg/kg), manganese (31 mg/kg), vitamin A (13,310 µg retinol/kg), vitamin D (460 µg cholecalciferol/kg), vitamin E (660 mg RRR‐α‐tocopherol/kg), thiamin (5 mg/kg), vitamin B12 (650 µg/kg), and methionine (29 g/kg). Gut‐loading diets for silkworms should be supplemented to contain the following nutrients: Ca (23 g/kg), iodine (0.7 mg/kg), vitamin D (140 µg cholecalciferol/kg), vitamin E (70 mg RRR‐α‐tocopherol/kg), and vitamin B12 (226 µg/kg). Zoo Biol 22:147–162, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   

10.
A variety of insects are commonly fed to captive insectivores but detailed nutritional analyses are only available for the most commonly fed species. Soldier fly larvae, Turkestan cockroach nymphs, tebo worms, and adult house flies were analyzed for moisture, protein, fat, ash, acid detergent fiber, neutral detergent fiber, minerals, amino acids, fatty acids, vitamins, and selected carotenoids. The acid detergent fiber was analyzed for amino acids to estimate chitin content. Nutrient content varied widely between the four insect species. Ranges for the macronutrients were as follows: moisture (60.2–74.8%), crude protein (15.5–19.7%), crude fat (1.9%–29.4%), acid detergent fiber (1.4–3.0%), neutral detergent fiber (2.6–3.8%), and ash (0.8–3.5%). Energy content ranged from a low of 918 kcal/kg for house flies to 2,977 kcal/kg for tebo worms. The chitin content of these four species ranged from 6.7 to 21.0 mg/kg. The nutrients most likely to be deficient when these species of insects are used as food for insectivores are vitamin A, vitamin D, calcium, vitamin E, thiamine, iodine, and vitamin B12. The number of nutrients deficient vs. the NRC requirements for rats on an energy basis by insect species was as follows: soldier fly larvae (3), tebo worms (15), Turkestan cockroach nymphs (5), and adult house flies (6). These data are valuable in helping assess the nutrient intake of captive insectivores and in developing gut‐loading diets to improve the nutrient intake of captive insectivores. Zoo Biol. 32:27‐36, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

11.
Water content was decreased in the needles of Scots pines (Pinus sylvestris L.) with moderate and slight levels of stress-induced decline. In pines with moderate decline a misbalance of foliar nutritional elements was observed. In 1-year-old needles of afflicted pines, the content of potassium and calcium was decreased, but the content of phosphorus, magnesium, iron, manganese and of the heavy metals cadmium and lead was increased. In 2-year-old needles of damaged pines, the content of calcium, iron and of the heavy metal cadmium was decreased, but the content of phosphorus, magnesium, manganese and zinc was increased. Potassium deficiency and zinc levels above toxicity tolerance characterized the nutrient status of declined Scots pines. In the same pines chlorophyll a/b ratio was diminished in 2-year-old needles and the protein content was increased in 1-year-old needles but was decreased in 2-year-old needles.In the second phase of the study 25- and 40-year-old pines with slight decline were examined. An increase in the protein content of 2-year-old needles of 25-year-old declined pines and of both 1- and 2-year-old needles of older 40-year-old pines was observed. A 280% increase of peroxidase activity in 1-year-old and a 178% increase in 2-year-old needles of 25-year-old damaged pines were shown. In older 40-year-old damaged pines a slight increase only in 1-year-old needles was seen. The observed age-related decrease in peroxidase activity in older 40-year-old symptomatic pines might be responsible for the lower resistance to decline in older pines. Our results show that clear but complex chemical and biochemical changes are observed in the needles of Scots pines in Bulgaria and that these changes hold promise for use as indicators of stress.  相似文献   

12.
The present study was conducted to investigate whether hair calcium levels are related to nutritional habits, selected status parameters, and life-style factors in young women. Eighty-five healthy female students neither pregnant nor lactating, using no hair dyes or permanents were recruited for the study. Food consumption data, including fortified products and dietary supplements were collected with 4-day records. The calcium levels in hair and serum were analyzed by atomic absorption spectroscopy. Serum osteocalcin and the C-terminal telopeptide of type I collagen were assayed by ELISA. The women were divided into four groups according to their total vitamin D and calcium intakes and hair calcium levels. At adequate calcium intake and comparable serum bone biomarker levels, supplemental vitamin D increased the hair calcium levels. On the other hand, at lower than estimated adequate requirement of vitamin D intake the hair calcium levels were comparable in women with low calcium intakes but consuming high amounts of meat products or those whose diets were rich in dairy products, possibly due to homeostatic mechanisms. Elevated hair calcium was seen in 25% of subjects and could not be related to nutritional or life-style factors. The results show that the hair calcium levels were weakly related to the quality of diet, with some synergistic interactions between nutrients, especially vitamin D and magnesium.  相似文献   

13.
Summary Intracellular perfusion technique has been applied to the muscle fibers of the barnacle species,Balanus nubilus. In these fibers, generation and the form of the calcium spike was governed by the frequency of stimulation and intra- and extracellular calcium concentrations. Voltage-clamp experiments showed that the magnitude of the potassium outward current was controlled by the intracellular calcium concentration whose increase, nearly 103-fold, raised the resting membrane conductance and the outward potassium current. On the other hand, application of 10mm zinc ions inside the muscle fiber had no effect on either the resting potential or the outward potassium current but suppressed the early inward calcium current. Similarly, the inward calcium current was decreased by low concentration of sodium ions in the extracellular fluid only when its ionic strength was made low by substituting sucrose for the sodium salt. Measurement of outward current with the muscle fiber in calcium-free ASW solution and intracellularly perfused with several cationic solutions established the selectivity sequence TEA相似文献   

14.
Neonates, 11‐day‐old, and 17‐day‐old captive‐bred bearded dragons (Pogona vitteceps) and wild‐caught adult anoles (Anolis carolinensis) were chemically analyzed to determine the whole‐body concentrations of vitamins E and A, crude protein, and minerals. Significant differences (P<0.05) were noted between neonates and older age groups of the bearded dragons for concentrations of all the minerals except calcium (Ca) and phosphorus (P). The neonatal animals generally exhibited lower concentrations of all minerals, except for magnesium (Mg) and iron (Fe), than did the older lizards. The concentration of vitamin E was higher, and that of vitamin A was lower in neonates than in older animals. The whole‐body concentrations of protein, vitamins A and E, Ca, P, potassium (K), sodium (Na), copper (Cu), and manganese (Mn) differed significantly between the bearded dragons and anoles. Zoo Biol 21:489–497, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   

15.
Adolescence is marked by intensive growth and development. When pregnancy occurs during this period of the mother’s growth, there is an increase in her nutritional needs. The aim of this study was to determine the levels of calcium, iron, copper, and zinc in maternal plasma, the placenta, and in the cord plasma of pregnant teenagers and adults. A total of 80 sets of maternal plasma, placentas, and cord plasma (40 from teenagers and 40 from adults) were analyzed using synchrotron radiation total reflection X-ray fluorescence. The levels of calcium, copper, and zinc in the maternal and cord plasma from teenagers were not significantly different than those from adults. Iron levels in the teenagers maternal and cord plasma were higher than in the adults. All of the minerals analyzed were present at higher levels in the placentas from adults than those from teenagers. However, the low quantities of placental calcium, iron, copper, and zinc in the teenagers do not compromise the levels of these minerals in the cord plasma. Future research regarding the placental transport of these minerals is recommended to investigate the efficiency of mechanisms of transfer of these minerals in pregnant teenagers.  相似文献   

16.
The aim of the present study was to investigate the influence of nutritional deficiency and dietary addition of vitamins (B2, B6, and folate) on hepatic concentration of zinc and copper in rats. The experiment was performed on 260 growing male Wistar rats divided into 13 groups. Animals of 11 groups were fed isocaloric diets (14.7 MJ/kg) in which the 20% of energy was derived from protein. Another two groups of rats were offered diets with 9% or 4.5% of energy originating from protein. Animals of both mentioned groups and of the control group (20% of energy from protein) were offered diets ad libitum. The other 10 groups were offered 50% and 30% of the amount consumed in the control group. Eight groups, from those 10 restricted ones, were differentiated by dietary addition of vitamins B2 and B6 and folate (300% addition). Restricted feed intake did not affect the liver zinc concentration but significantly increased the copper concentration. The addition of vitamin B6 decreased the liver Zn concentration. The highest liver Cu concentration was noted in rats offered restricted diets to only 30% of intake in the control group and high in vitamin B2 and in rats supplemented with all of studied vitamins together. It suggests that vitamin B2 had the strongest impact on liver Cu concentration in rats fed restricted diets.  相似文献   

17.
doi: 10.1111/j.1741‐2358.2011.00579.x
Impact of tooth replacement strategies on the nutritional status of partially‐dentate elders Objective: To investigate the impact of tooth replacement on the nutritional status of partially dentate older patients, and, to compare two different tooth replacement strategies; conventional treatment using removable partial dentures and functionally orientated treatment based on the shortened dental arch. Background: Amongst older patients, diet plays a key role in disease prevention, as poor diets have been linked to numerous illnesses. Poor oral health and loss of teeth can have very significant negative effects on dietary intake and nutritional status for elderly patients. There is evidence that good oral health generally, has positive effects on the nutritional intake of older adults. Materials and methods: A randomised, controlled clinical trial was designed to investigate the impact of tooth replacement on the nutritional status of partially dentate elders. Forty‐four patients aged over 65 years completed the trial, with 21 allocated to conventional treatment and 23 allocated to functionally orientated treatment. Nutritional status was accessed at baseline and after treatment using the Mini Nutritional Assessment (MNA) and a range of haematological markers. Results: At baseline, relationships were observed between the number of occluding tooth contacts and some measures of nutritional status. As the number of contacts increased, MNA scores (R = 0.16), in addition to vitamin B12 (R = 0.21), serum folate (R = 0.32) and total lymphocyte count (R = 0.35), also increased. After treatment intervention, the only measure of nutritional status that showed a statistically significant improvement for both treatment groups was MNA score (p = 0.03). No significant between group differences were observed from analysis of the haematological data. Conclusion: In this study, prosthodontic rehabilitation with both conventional treatment and functionally orientated treatment resulted in an improvement in MNA score. Haematological markers did not illustrate a clear picture of improvement in nutritional status for either treatment group.  相似文献   

18.
The aim of this study was to evaluate the reliability and effectiveness of direct determination of trace and major element concentrations in bronchoalveolar lavage fluid samples from Holstein calves with Mycoplasma bronchopneumonia (n = 21) and healthy controls (n = 20). The samples were obtained during bronchoscopy using a standard examination method. A total of 18 elements (aluminum, bromine, calcium, chlorine, chromium, copper, iron, potassium, magnesium, manganese, molybdenum, nickel, phosphorous, sulfur, silicon, strontium, titanium, and zinc) were detected by particle-induced X-ray emission. The average bromine, iron, potassium, magnesium, and phosphorous concentrations were higher in calves with bronchopneumonia than in controls (p < 0.05). They were found to have higher amounts of calcium and zinc, and a higher zinc–copper ratio than that in healthy calves (p < 0.001). Based on the receiver operating characteristics curves, we propose a diagnostic cutoff point for zinc–copper ratio for identification of Mycoplasma pneumonia of 8.676. Our results indicate that assessment of the elemental composition of broncholaveolar lavage fluid is a promising diagnostic tool for Mycoplasma bronchopneumonia.  相似文献   

19.
Understanding the mechanisms of intestinal zinc uptake in fish is of considerable interest from both nutritional and toxicological perspectives. In this study, properties of zinc transport across the apical membrane of freshwater rainbow trout intestinal epithelia were examined using right-side-out brush border membrane vesicles (BBMV's). Extravesicular calcium was found to have complex actions on zinc uptake. At a low zinc concentration of 1 microM, calcium (0.1-2 mM) significantly stimulated zinc uptake. In contrast, calcium inhibited zinc uptake at higher zinc levels (100 microM). Lanthanum and cadmium in the external medium did not block zinc uptake, suggesting that interactions between zinc and calcium were not exerted at a calcium channel. Copper also failed to exercise any inhibitory action. Zinc association with the BBMV's was enhanced by an outward potassium gradient. This stimulatory effect was only present at a zinc concentration of 100 microM. The potassium channel blocker, tetraethylammonium chloride inhibited zinc uptake at this relatively high zinc concentration, suggesting the presence of a low affinity zinc uptake pathway linked to potassium efflux. The present study provides evidence that the mechanism of intestinal zinc uptake in rainbow trout is pharmacologically very different from that of the piscine gill and the mammalian intestine.  相似文献   

20.
A perturbation of zinc metabolism has been noted in subjects with obesity. The present work intends to investigate whether the zinc nutritional status is associated with hyperinsulinemia in obesity. A study was carried out in a group of obese children and adolescents (n=23) and compared to a control group (n=21), both between 7 and 14 yr of age. Software analyzed diet information from 3-d food records. Body composition was evaluated by body mass index (BMI), bioelectrical impedance, and skinfold measurements. Zinc nutritional status was evaluated by Zn determination in plasma, erythrocyte, and 24-h urine, by atomic absorption spectrophotometry (λ=213.9 nm). Insulin was measured by radioimmunoassay (Linco Res). Diets consumed by both groups had marginal concentrations of zinc. Zinc concentrations in plasma and erythrocytes were significantly lower in the obese group. Urinary zinc excretion and serum insulin were significantly higher in the same group, although the insulinemia and the parameters of zinc nutritional status were not significantly correlated. As a result, considering that zinc is part of the synthesis and secretion of this hormone, an assessment is necessary of the possible participation of the oligoelement in the mechanisms of insulin resistance, commonly present in obese patients.  相似文献   

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