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1.
The effects of latent iron deficiency combined with parenteral subchronic or acute cadmium exposure during pregnancy on maternal and fetal tissue distribution of cadmium, iron and zinc, and on fetal viability were evaluated. Timed-pregnant Sprague-Dawley rats were fed on semisynthetic test diets with either high iron (240 mg kg) or low iron (10 mg kg), and concomitantly exposed to 0, 3 or 5 mg cadmium (as anhydrous CdCl2) per kilogram body weight. Animals were exposed to cadmium from gestation day 1 through 19 by subcutaneously implanted mini pumps (Subchronic exposure) or on gestation day 15 by a single subcutaneous injection (Acute exposure). All rats were killed on gestation day 19. Blood samples, selected organs and fetuses were removed and prepared for element analyses by atomic absorption spectrometry. Low iron diet caused decreases in maternal body weight, maternal and fetal liver weights, placental weights and tissue iron concentrations. By cadmium exposure, both subchronic and acute, tissue cadmium concentrations were increased and the increase was dose-related, maternal liver and kidney zinc concentrations were increased, and fetal zinc concentration was decreased. Cadmium concentration in maternal liver was additionally increased by low iron diet. Acute cadmium exposure caused lower maternal body and organ weights, high fetal mortality, and decreased fetal weights of survivors. In conclusion, parenteral cadmium exposure during pregnancy causes perturbations in essential elements in maternal and fetal compartments. Acute cadmium exposure in the last trimester of gestation poses a risk for fetal viability especially when combined with low iron in maternal diet.  相似文献   

2.
We investigated with an in vivo single pass perfusion technique, the effect of glucocorticoids on net magnesium and calcium absorption from the small and large intestine of suckling and adolescent rats. In control rats, rates of net magnesium and calcium absorption were several fold greater in both small and large intestinal segments of suckling rats compared to corresponding rates in segments of adolescent rats. Methylprednisolone 30 mg/kg body weight daily for three days, suppressed significantly net magnesium and calcium absorption from the small and large intestinal segments of suckling rats only. Methylprednisolone had no effect on either net magnesium or calcium absorption in adolescent rats. The mechanism(s) responsible for the observed decrease in net magnesium and calcium absorption in the suckling period by glucocorticoids are discussed.  相似文献   

3.
Selenium (Se) reduces cadmium (Cd) toxicity in adult animals, but its effects in newborn animals are still unknown. This study investigated Cd (as CdCl2) absorption, distribution, and retention in suckling rats receiving oral Se supplementation (as Na2SeO3) in equimolar doses (8 μmol Cd and/or Se per kg b.w./day). Selenium was given either before and during Cd exposure (Sepre + Cd group; pre-treatment group) or only during Cd exposure (Se + Cd group). Rats were treated from postnatal day (PND) 6–14 as follows: controls (H2O, PND 6–14), Se (PND 10–14), Cd (PND 10–14), Sepre + Cd (Se PND 6–14 + Cd PND 10–14) and Se + Cd (Se + Cd PND 10–14). Selenium supplementation, especially pre-treatment, decreased Cd levels in the blood, brain, liver and kidney of suckling rats. Selenium levels in plasma, brain, and kidney also decreased. These findings suggest that higher Se intake could efficiently reduce Cd retention during the suckling period.  相似文献   

4.
Ethanol ingestion is known to interfere with folate absorption and metabolism. A fostering/crossfostering analysis of maternal ethanol exposure effects on jejunum and ileum kinetic parameters in vivo of offspring rat folic acid absorption at 21 days postpartum was carried out. The rats were divided into four groups: CP, control pups; GP, pups exposed to ethanol only during gestation; LP, pups exposed to ethanol only during lactation; GLP, pups exposed to ethanol during gestation and lactation. Jejunal and ileal loop transport studies were performed using in vivo perfusion at a flow rate of 3 ml/min for 5 min. Folic acid concentrations of 0.25, 0.5, 1, 1.5 and 2.5 μm were used. Jejunal and ileal absorption values were determined by the difference between the initial and the final amounts of substrate in the perfusate and expressed as picomoles per square centimeter of intestinal surface every 5 min. The results indicated that ethanol consumption by the dams during gestation and/or lactation led to significant changes in V max, with no significant changes in apparent K m. These findings suggest that exposure to ethanol during gestational and suckling periods leads to a general delay in postnatal body weight and that intestinal folate absorption appears to be upregulated in suckling rats, this effect being higher in the LP group.  相似文献   

5.
The intestinal level of the vitamin D-dependent duodenal calcium-binding protein was assayed by an equilibrated column technique in rat embryos, neonates, and pups. Calcium-binding protein was undetectable in unborn, newborn, and 1- to 2-day-old rats i.e., the level was lower than in severely vitamin D-deficient animals. Calcium-binding protein was detected after the animals were 5-days old and thereafter rose monotonically as a function of body weight. Treatment with 1,25-dihydroxyvitamin D3 failed to raise the calcium-binding protein levels of newborn or 1-day-old rats, but doubled the level in 11- or 12-day-old pups. Plasma calcium was raised in all treated animals. The failure to detect calcium-binding protein in vitamin D-replete suckling animals provides evidence for a dissociation between calcium absorption and calcium binding protein.  相似文献   

6.
The effects of cadmium (Cd) were evaluated in offspring exposed from birth until weaning (neonatal day 0–21) and 4 weeks after exposure cessation focusing on iron (Fe) and zinc (Zn) levels in organs and hematological parameters. Wistar female rats were administered 50 mg Cd/L in drinking water (Cd-exposed) for 4 weeks before mating and during 3 weeks of gestation plus 3 weeks of lactation. Controls were supplied drinking water. At birth, part of Cd-exposed dams’ litters was cross-fostered to control dams (CCd group) and their control litters were cross-fostered to Cd-exposed dams (CdC group). This procedure enabled to discern the effects of gestational, lactational and gestational plus lactational Cd exposure until weaning in F1 offspring. Elements were analyzed by atomic absorption spectrometry; hematological parameters manually; and histopathological changes by light microscopy. Gestational plus lactational exposure in Cd-exposed dams and their offspring increased Cd and decreased Fe levels, increased Zn in dams and decreased Zn and body weights in 11- and 21-day pups. In 21-day weanling pups, decreased red blood cell (RBC) count, hemoglobin and hematocrit values and increased reticulocytes in peripheral blood were also found with concomitant histopathological finding of extramedullary hematopoiesis in the liver. In cross-fostered pups with gestational exposure (CCd pups), Fe in the liver decreased on day 11 and Zn increased in the kidney on day 21 whereas in pups with lactational exposure (CdC pups) Zn in the brain decreased on day 11 and Fe decreased in the liver and brain on day 21. Regardless of exposure cessation at weaning, in offspring with gestational plus lactational exposure (Cd-exposed) body weights, kidney and brain Fe levels and RBC and hemoglobin remained decreased in blood until puberty. Furthermore Zn levels increased in the liver, kidney and brain. It was concluded that gestational plus lactational Cd exposure caused decreases in Fe and Zn levels and hematotoxic effects in F1 offspring more pronouncedly than exposure during either gestational or lactational period alone and the adverse effects of maternally mediated Cd exposure continued after exposure cessation into adulthood.  相似文献   

7.
Undernutrition during suckling was induced in newborn rats by increasing the litter size to sixteen pups to be fed by one mother. Animals reared in litters of eight served as controls. Undernourished animals showed retarded body and testicular growth during a suckling period of 22 days. Sequential morphogenesis of the testis was not altered up to 15 days of age. However, certain morphological alterations in Sertoli cells and Leydig cells were observed from 15 days onwards. Cell generation cycle of spermatogonial germ cells and supporting cells (future Sertoli cells) on day 9 showed marked prolongation of DNA synthetic phase (S), unaltered post-DNA synthetic phase (G2) and total cycle (Tc) and shortening of the pre-DNA synthetic phase (G1) indicating a depression in DNA synthesis in undernutrition.  相似文献   

8.
In a previous study, carnitine supplementation to piglets during the suckling period resulted in an increased total muscle fibre number at weaning in piglets of low birth weight. The objective of the present study was to investigate whether this effect is maintained until market age and whether this would attenuate the negative consequences of low birth weight on carcass and meat quality. Using a split-plot design with litter as block, sex as whole plot and treatment as subplot, the effects of early-postnatal l-carnitine supplementation on female and castrated male piglets of low birth weight were investigated on a total of 56 German Landrace piglets from 14 litters. From days 7 to 27 of age piglets were orally supplemented once daily with 400 mg of l-carnitine dissolved in 1 ml of water or received an equal volume of water without carnitine. From weaning (day 28) until slaughter (day 166 of age) all pigs were fed standard diets. At weaning, carnitine-supplemented piglets had a twofold increased concentration of free carnitine (P < 0.001) and a lower concentration of non-esterified fatty acids (P < 0.05) in blood plasma indicating that carnitine became bioavailable and increased fatty acid utilization during the period of supplementation. Growth performance was not influenced by treatment in any growth period. Dual-energy X-ray absorptiometry revealed no differences in body composition between groups in weeks 12, 16 and 20 of age. LW at slaughter, carcass weight, measures of meat yield and fat accretion, as well as body composition by chemical analyses and dissection of primal cuts did not differ between treatments. No differences between control and carnitine-treated pigs in total fibre number (P = 0.85) and fibre cross-sectional area (P = 0.68) in m. semitendinosus (ST) measured at slaughter could be observed. The carnitine group tended to exhibit a smaller proportion of slow-twitch oxidative fibres (P = 0.08), a greater proportion of fast-twitch glycolytic fibres (P = 0.11), and increased specific lactate dehydrogenase activity (P = 0.09) in ST indicating a more glycolytic muscle metabolism. Compared with the controls, a lower pH24 value was observed (P = 0.05) in ST muscle of carnitine-supplemented pigs, which – in castrates only – was associated with an increased drip loss (P < 0.01). Meat quality traits in m. longissimus were not influenced by treatment. In conclusion, our hypothesis that early-postnatal carnitine supplementation to piglets of low birth weight permanently increases myofibre number and improves later carcass and meat quality could not be confirmed by this experiment.  相似文献   

9.
The purpose of the present study was to evaluate the effect of a dietary vitamin C supplement on cadmium absorption and distribution in an animal model. An aqueous solution of cadmium chloride (labelled with cadmium-109) was given by gavage to male Wistar rats for 28 days at a daily dose corresponding to 10 mg Cd/kg diet (1.0-1.2 mg Cd/kg b.w.). The animals assigned to groups 1 and 2 (45 animals per group) received a standard laboratory diet LSM, and tap water or tap water supplemented with ascorbic acid (1.5 mg/l), respectively. The radioactivity of the samples was measured using a liquid scintillation counter (tissue samples) and a gas-flow automatic counter (ashed carcasses). The fractional uptake of cadmium-109 in the carcass and organs was evaluated within 32 days after treatment by dividing the cadmium-109 activity in the whole sample by the total activity of cadmium-109 administered for 28 days. Results were compared using AUC (areas under the concentration time curve) values. The vitamin C supplement decreased the carcass cadmium burden and the cadmium content in the liver, kidneys, testicles and muscles; the highest decreases were found in the testicles, the lowest ones in the muscles. In addition, the rats supplemented with vitamin C revealed an improved body weight gain during the experimental period.  相似文献   

10.
The bioavailability of zinc and manganese from diets used for very low birthweight infants was investigated in a rat pup model using radioisotopes. The effect of protein source and content and of pasteurization was evaluated, and two different approaches for evaluation of zinc and manganese bioavailability in the rat pup model were compared. Zinc and manganese bioavailability from the studied human milk and infant formula for very low birthweight infants was high. Liver uptake of65Zn from labeled premature infant diets in sucklings rat pups was 26–29%, and absorption calculated as the difference between administered dose and nonabsorbed activity 6 h after oral intubation was 93–95%. Retention of manganese calculated as the sum of54Mn retained by organs and carcass was 85–95% from human milk and premature infant formula and absorption calculated from nonabsorbed activity was 83–88% after 6 h. Fortification of early human milk significantly increased the bioavailability of zinc. No effect of pasteurization of human milk was found on zinc or manganese bioavailability. Liver zinc uptake was found to be a more sensitive parameter than absorption for evaluation of diets with a high zinc bioavailability. Measurement of retained activity of manganese in carcass and organs was judged to be the preferred parameter for evaluation of diets with high manganese availability.  相似文献   

11.
The aim of the present investigation was to study the effect of a varying maternal vitamin B6 supplementation during lactation period on vitamin B6 levels in blood, liver and total body, and on the activity of two transaminase enzymes in the offspring. Therefore, eighty female Sprague‐Dawley rats were fed a semi‐synthetic diet (0.2 mg vitamin B6 per kg) which was supplemented during gravidity with 5 mg vitamin B6 per kg diet. During the following lactation period the rats were assigned to one of 10 vitamin B6 treatment groups (supplementation of 0, 3, 6, 9, 12, 15, 18, 36, 360, 3600 mg vitamin B6 per kg diet). At day 14 of lactation the pubs of all dams were decapitated and blood, liver, and carcass were used for analysis of vitamin B6 concentration, activities of two transaminases, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in plasma, erythrocytes, and liver, and of haematological parameters.

While the liver and total body wet weights as well as the haematological parameters (red blood cells, haemoglobin concentration, hematocrit, middle corpuscular cell volume, middle corpuscular haemoglobin, middle corpuscular haemoglobin concentration) did not differ within the experimental groups, the present data clearly show that in blood, liver and total body of the offspring exists a slight dose‐response relationship between the maternal dietary vitamin B6 supplementation and the vitamin B6 concentration. Concerning the activities of the transaminases a dietary supplementation above 3mg vitamin B6 per kg diet had no influence on the AST and ALT activities in offspring plasma. In the erythrocytes no statistical significant influence of the vitamin B6 supplementation during lactation on the activities of AST and ALT was found. The activities of ALT and AST in liver were not consistently altered by the vitamin B6 supplementation of the dams during lactation. In conclusion these results indicate that a minimal maternal dietary vitamin B6 supply of 3.1 mg per kg diet is necessary with regard to health and development of their offspring. But not all of the analysed parameters as the liver and total body weights, the activities of AST and ALT in the erythrocytes, and the haematological parameters were influenced by a deficient maternal dietary vitamin B6 supply.  相似文献   

12.
This study was designed to determine the effect of zinc on the biological half-lives of 65Zn in whole body and liver and on distribution of 65Zn in different organs of rats following nickel toxicity. Sprague-Dawley (SD) rats received either nickel in the form NiSO4·6H2O at a dose of 800 mg/L in drinking water, zinc in the form of ZnSO4·7H2O at a dose of 227 mg/L in drinking water, and nickel plus zinc or drinking water alone for a total duration of 8 wk. All of the rats were injected with a tracer dose of 0.37 MBq 65Zn at the end of the treatment period. The effects of different treatments were studied on biological half-lives of 65Zn in whole body and liver and on the distribution of 65Zn in different organs of rats. In the present study, we have noted that nickel treatment to normal rats caused a significant decrease in the slow component (Tb2) in liver, which improved following zinc supplementation. Nickel administration to normal-diet-fed animals caused significant lowering in the percentage uptake of 65Zn values in the brain, liver, and intestine. However, the administration of zinc to nickel-treated rats improved the status of 65Zn in different organs. The Tb2 in the liver and the percentage uptake of 65Zn values elevated following zinc supplementation to nickel-treated rats.  相似文献   

13.
The effect of repeated oral administration of prostaglandin analogue (dmPGE2) on intestinal macromolecular transport and digestive enzymes development were investigated in the suckling rats. By the administration of dmPGE2 for 7 days, precocious induction of maltase activity, depression of amylase activity and enhancement of trypsin activity in the pancreas occurred. Absorption of bovine IgG was dose dependently depressed by drnPGE2 treatments. The intestinal cessation was also observed in the adrenalectomized pups, but was not influenced by difluoromethyl ornithine administration. These results suggest that oral administration of PGE2 induces precocious maturation of the small intestine and exocrine pancreas and that the intestinal cessation is not directly related to ornithine decarboxylase activity in the suckling rats.  相似文献   

14.
This study was conducted to investigate the effects of various levels of dietary chromium supplementation on performance, carcass traits, blood chemistry, and tissue distribution of chromium (Cr3+) in quails. Two hundred forty 1-d-old Japanese quails were divided into five groups with four replicates and were fed a basal diet or the basal diet supplemented with 20, 40, 80, or 100 mg/kg Cr (CrCl3·6H2O) until 38 d of age. Chromium supplementation decreased carcass fat percentage, serum low-density lipoprotein (LDL), and glucose and increased serum magnesium (Mg) and Cr content of kidney, liver, and muscle. In conclusion, 20, 40, 80, or 100 mg/kg Cr supplementation to quail diet had no effect on performance, chemical composition of carcass except fat percentage, serum protein, calcium (Ca), and inorganic phosphorus (Pi) levels, but reduced serum glucose, LDL and fat percentage of carcass. Chromium is accumulated mainly in the kidneys and liver.  相似文献   

15.
Piglet body composition at weaning could be a determinant for pig’s viability and may be influenced by factors such as the nutritional management followed during suckling. An experiment was conducted to study whether intermittent suckling (IS) affects body composition at weaning and nutrient and energy retention during a 34-day lactation period in Iberian piglets. Litters were subjected to conventional suckling (CS) or IS (n=10 litters of six piglets per treatment) in two trials. All piglets had ad libitum access to creep feed from day 15 onwards. In IS, piglets were progressively separated from the sow for 6, 8 and 10 h daily during the last week of lactation, whereas in CS piglets had continuous access to their dams. Creep feed intake in litters and BW development of individual piglets were measured throughout the 34-day lactation. Within each litter, both at birth and at weaning (day 35), one piglet was used to assess nutrient retention and body composition by the comparative slaughter approach. During days 29 to 35 of the experiment, daily creep feed intake was greater in IS piglets (IS 124, CS 67 g/piglet, P=0.040), and average daily gain differed significantly between groups (IS 190, CS 150 g/day, P=0.010). BW at weaning was higher in the IS than in the CS piglets (IS 8.19, CS 7.48 kg, P=0.011). Empty-body fat and energy content at weaning were higher in the IS compared with CS litters, as well as fat content in the carcass (P=0.04). The IS treatment did not affect empty-body protein deposition, but significantly increased daily retention of fat, energy, ash and calcium, compared with CS litters (P<0.05). Thus, IS in Iberian piglets seems to enhance feed intake, growth rate and retention of some body components, which may contribute to a higher body fat content at weaning and facilitate the weaning process.  相似文献   

16.
17.
Genistein aglycone (GEN) has a favorable effect on bone loss. We investigated the effects of GEN alone or in combination with supplemental calcium and vitamin D3 in an animal model of bone loss to evaluate if there was additional benefit. Ovariectomized (OVX) and SHAM-OVX rats were used. OVX were divided into 12 groups and randomized to receive: GEN at 27, 54, 200, 500 or 1000 mg (human equivalent dose (HED)/day/ip injection alone or with calcium carbonate (Ca) (360 mg/kg/day/gavages) and vitamin D3 (D3) (50 IU/kg/day/gavages) or Ca/D3 without GEN or untreated for 6 weeks. SHAM-OVX were randomized into 7 groups and treated with: Ca and D3 alone or in combination with GEN (same doses as OVX), or left untreated. Bone mineral density (BMD), bone-alkaline phosphatase (b-ALP), collagen C-telopeptides (CTX), osteoprotegerin (OPG) and soluble receptor activator of NFκB ligand (sRANKL) were assessed. Femurs were excised and tested for breaking strength and histology. Uterine weight was analyzed to assess GEN's estrogenic effects on the SHAM-OVX.The most effective dose of GEN, independent of Ca/D3 supplementation, was 54 mg/day. Higher doses yielded no further improvement in bone biomarkers, histology or strength. Only 1000 mg/day HED of genistein produced statistically significant changes in uterine weight of the SHAM-OVX. This study suggests that 54 mg/day of GEN is the threshold dose for efficacy. In addition, supplemental calcium and vitamin D3, beyond normal dietary intake do not enhance the effects of genistein on improving measures of bone loss. This observation has implications regarding the use of calcium and vitamin D3 supplementation.  相似文献   

18.
ABSTRACT

The aim of the study was to investigate if dietary alpha-ketoglutarate (AKG) supplementation may improve the performance of lactating sows and their suckling piglets. After farrowing, 24 lactating sows (Large White × Landrace) with similar body weight (BW) were assigned to the control and AKG groups based on parity, and their lactation diets were supplemented with 0.00 or 0.25% AKG, respectively. It was found that supplementing the diet of lactating sows with 0.25% AKG enhanced growth performance of the suckling piglets from d 7 to d 21 of the lactation period, improved villus height of ileum and tended (p = 0.085) to increase mean volumetric bone mineral density of femur in the weanling piglets. In the lactating sows, dietary supplementation of AKG decreased plasma urea level on d 14 of lactation, decreased plasma calcium (Ca) concentrations from d 7 to d 21 of lactation and increased lactose and Ca levels in ordinary milk. Thus, it was proposed that AKG supplementation stimulates the capacity for lactose synthesis and Ca uptake in the mammary gland, thereby altering the composition of the ordinary milk which might be associated with the enhanced performance of piglets during the suckling period. These findings could lead to a better application of AKG in lactating nutrition, and therefore, promoting pork production.  相似文献   

19.
Gibberellic acid (GA3) is an endogenous plant growth regulator used worldwide in agriculture. The objective of this study was to investigate the effects of GA3 on the kidney function of adult rats and their pups. Female Wistar rats were given daily 200 ppm GA3 in drinking water from the 14th day of pregnancy until day 14 after delivery. GA3 induced nephrotoxicity, as evidenced by a reduction in the 24-h urine volume and an increase in plasma creatinine, urea and uric acid levels. Nephrotoxicity was objectified by a significant increase of malondialdehyde level and a decrease of antioxidant enzyme activities like catalase, superoxide dismutase, glutathione peroxidase and glutathione content in kidneys of suckling pups and their mothers. Kidney histological studies confirmed biochemical parameters. We concluded that the exposure of rats to GA3 induced oxidative stress and histopathological changes in kidneys of suckling rats and their mothers during late pregnancy and early postnatal periods.  相似文献   

20.
The effects of cadmium (Cd (II)) on absorption, excretion, and distribution of nickel (Ni (II)) were studied in rats using 63Ni-NiCl2 as radiotracer in the presence and absence of CdCl2, through intraperitoneal injection (i.p.). The time–concentration curves in the blood were fitted with a two-compartment model. The peak time (t (peak)) is 0.31 h in the absence of Cd (II), and it is 5.5 h in the presence of Cd (II). The levels of nickels were higher at 3 h and lower (close to zero) at 24 h in all organs of interest, except kidneys, in the absence of Cd (II). There still residue Ni (II) at 72 h post-injection in the presence of Cd (II). The Cd (II) did effect the total Ni (II) excretion 24 h post-injection. Our study showed that cadmium has a competitive effect on the absorption of nickel and an inhibitory effect on the elimination of it, so cadmium may induce the bioaccumulation of nickel in the body.  相似文献   

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