The effect of the zinc content in the rations of experimental animals on the absorption, distribution and accumulation of cadmium chloride in the body with different methods of administration]

Intravenous (20 kBk) and intragastric (400 kBk) cadmium chloride administration to 45 white noninbred rat males kept for a month on a semisynthetic isocaloric diet including 0.0005 and 0.001% zinc were evaluated for absorption and distribution. Radionuclide findings provided the conclusions that: the absence or excess of zinc in the diet stimulates cadmium absorption from gastrointestinal tract; cadmium distribution in the viscera (the liver, kidneys, pancreas) varies with route of entry, the least accumulation of oral cadmium in the above viscera is observed in animals receiving optimal zinc quantities.     

Effect of the amount of protein and calcium in the diet on cadmium chloride distribution and accumulation in the body when administered by different routes

The authors studied distribution and accumulation of cadmium chloride after its intravenous (i. v.) or intragastric (i. g.) administration to experimental rats, which received diets with varying content of protein (18, 30 and 5%) and calcium (0.6, 2.4, 0.1%), during one month. A high level of cadmium chloride was recorded in the liver after i. v., and in the kidneys after i. g. administration. The highest level of cadmium chloride was observed in the kidneys after i. g. administration to rats which were given diets with high protein content. A balanced content of protein and calcium in the diet promoted diminution of cadmium chloride accumulation in the body.     

Comparative evaluation of the biological availability of dietary and mineral cadmium

Experiments on rats were made to study absorption, distribution in tissues and bioavailability of feed (internal label) and mineral (external label) cadmium-109. It was established that feed cadmium is absorbed from the gastrointestinal tract 6 times less effective as compared with an aqueous solution of cadmium chloride. In internal label, there takes place more rapid and more complete translocation of cadmium from blood plasma to red cells, whereas it bioavailability for the basic organs of deposition (kidneys, liver) is 5 times as decreased. Possible causes of the events described are discussed.     

Calcium sources for milk production in Holstein cows via changes in dry matter intake, mineral utilization, and mineral source buffering potential

Three supplemental sources of inorganic calcium (calcite flour, aragonite, albacar), each differing in particle size and rate of reactivity, provided .6 or .9% calcium in corn silage:grain (1:1 dry matter) diets of high producing dairy cows. All cows were fed calcite flour at .6% calcium during the first 4 wk of lactation. On d 29 of lactation 5 cows were assigned to each of the six diets. Peak milk yield paralleled dry matter intake and was higher when calcite flour and aragonite provided .9% calcium, intermediate when all sources provided .6% calcium, and lower when albacar provided .9% calcium. However, adaptations to calcium source and to particle sizes of a calcium source (.35 to 1190 mu) were made within 40 d by lactating Holsteins. Starch increased and pH decreased in feces of cows fed albacar. Increasing calcium in the diet provided more buffering capacity in the gastrointestinal tract. True absorption of calcium did not differ from linearity due to source when fecal calcium was regressed on ingested calcium but did vary as a function of diet percentage. Thus, calcium retention was increased when cows were fed .9 vs. .6% calcium. These data suggest that a slow reacting (coarser) inorganic calcium source should be fed at a higher amount to optimize feed intake and milk production.     

Effect of dietary proteins on phospholipid transport between the subcellular membranes and restoration of lipid-transporting proteins in the liver

It has been demonstrated in experiments on Wistar rats that change in the protein quality and quota in the diet exerts an effect on intracellular phospholipid transport in the liver. In this case, the rate of the renewal of lipid-transporting proteins (LTP) in the liver decreases only with a considerable diminution of protein (6% of the diet caloric value). Sufficient quota of vegetable proteins in the diet (12% of the caloric value) produced changes in the rate of LTP synthesis only in the process of adaptation to a new protein source, deficient in individual amino acids.     

Egg yolk protein and egg yolk phosvitin inhibit calcium, magnesium, and iron absorptions in rats

ABSTRACT:  Egg yolk decreases the absorption of iron. The effects of egg yolk protein and egg yolk phosvitin on the absorption of calcium, magnesium, and iron were investigated by in vivo studies. Male Wistar rats were fed purified diets containing casein, soy protein, or egg yolk protein for 14 d. The apparent absorptions of calcium, magnesium, and iron in the rats fed the yolk protein-based diet were lower than those in rats fed the casein- and soy protein-based diets. The apparent phosphorus absorption and the apparent protein digestibility in the yolk protein group were lower than those in the casein and soy protein groups. In the feces of the yolk protein group, serine comprised more than 30% of the amino acids. The addition of egg yolk phosvitin to the casein diets at levels of 1% and 2% (w/w) produced effects on calcium and magnesium absorptions similar to those produced by the diet containing yolk protein. The tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) pattern suggested that phosphopeptide fragments having molecular masses of 28, 22, and 15 kDa were evident in the contents of the small intestine of the rats fed phosvitin diets. These results indicate that yolk protein, when compared with casein and soy protein, decreases calcium and magnesium absorption via the resistance of phosvitin to proteolytic action.     

Diet calcium and pH versus mineral balance in Holstein cows 84 days pre- to 2 days postpartum.

Sixteen dry Holstein cows were assigned four groups combining either .2 or 2.1% calcium and pH of either 4.5 or 6.1 in a 2 X 2 factorial arrangement of treatments to study the effect of diet calcium and acidity (pH) on voluntary intake of dry matter, mineral metabolism, and blood constituents. The 86-day experiment was started 84 days prepartum and completed 2 days postpartum. Voluntary dry matter ingestion tended to be higher with higher calcium and acidity (lower pH) diets. Calcium nutriture was improved by more acid diets. More total calcium was apparently absorbed (26 and 7 g) when the diet contained 2.1% calcium, but the .2% calcium diet resulted in a higher apparent percent absorption (25 and 17%) during the dry period. An increased apparent absorption (70 and 5 g) and utilization of diet calcium occurred with the higher calcium treatment at 2 days postpartum. Magnesium and phosphorus utilizations were improved with lower diet calcium. Although experimental treatments had no significant effect on blood minerals, serum calcium decreased 12% 2 days postpartum. A better calcium nutriture was provided by the higher calcium diets when the diets maintained a positive balance for magnesium and phosphorus.     

Availability of calcium from kilkeerai (Amaranthus tricolor) and drumstick (Moringa oleifera) greens in weanling rats

The present study was undertaken to determine the extent of calcium absorption in weanling rats from two types of greens rich in oxalates. The edible portions of greens namely kilkeerai (Amaranthus tricolor) and drumstick (Moringa oleifera) were analysed for moisture, calcium and total and soluble oxalates. Three groups of 6 male weanling albino rats were fed ad libitum on milk diet and two experimental diets containing greens. Urine and faecal samples were collected for a period of 7 days after 5 days of acclimatization period and were analysed for calcium. From the values obtained percent absorption and retention of calcium were calculated. Results revealed that calcium absorption and retention from milk diet (92 and 78%, respectively) were significantly higher than greens. Average calcium absorption and retention from greens diet were 75.5 and 60%, respectively. Presence of oxalates inhibited intestinal absorption of calcium.     

Biochemical quality assessment of broiler production using a hydrogen bacteria biomass in the diet

The authors studied the biochemical composition of the meat of broilers, eggs, liver and muscles of laying hens of 3 generations on a 5, 10, 25, 50 and 100% (broilers), 10 and 20% (laying hens) replacement of the animal protein quota in the diet by protein obtained from the hydrogen bacteria Alcaligenes eutrophus L-1. No deterioration of the quality of the produce was found from the standpoint of the main biochemical parameters.     

The effect of formulated goats' milk on calcium bioavailability in male growing rats

BACKGROUND: There are two main proteins in milk; whey and casein. Casein contains casein phosphopeptides (CPP), which are released on digestion of the milk. These may increase calcium solubility by binding calcium in the small intestine. Thus increasing casein in the diet may help to stimulate bioavailability of calcium and increase bone density. The present study tested this hypothesis in growing male rats fed diets containing three different concentrations of casein from goat milk. RESULTS: Rats fed the diet containing no casein had significantly lower calcium absorption when compared to rats fed the diets that contained 80% and 57% of goat milk protein as casein; however, no significant difference was observed between rats fed diets with 80% and 57% casein. The varying amounts of casein had no effect on mineral uptake or retention in the femur. Biomechanical testing and mineral analysis of the femurs showed no differences between diet groups. The mechanism to explain this lack of retention remains unclear. CONCLUSION: The diets containing 80% and 57% of goat milk protein as casein delivered increased calcium absorption compared to the diet containing no casein, suggesting a minimum level of casein is needed to optimize calcium absorption from goat milk. Copyright © 2009 Society of Chemical Industry     

Comparison of the resistance during proteolysis of the antigenic structure of bovine serum albumin, chicken ovalbumin and their carbohydrate-modified forms

A study was made of the effect of Maillard reaction between epsilon-amino groups of proteins and sugar carbonyl groups on the resistance of protein antigens (AG) to proteolysis in model systems and in the course of digestion and absorption in the gastrointestinal tract of adult rats. It was found that in vitro pepsin and trypsin inactivate antigenic determinants of bovine serum albumin (BSA) modified by carbohydrate less readily than those of basic protein. At the same time in the course of studying the cleavage and absorption of 3H-proteins and their glucose derivatives in the rat body, lack of a significant stabilization of modified BSA and ovalbumin as compared with non-modified ones was discovered. The discrepancy of the data derived in vitro and in vivo is likely to be related to the inadequacy of the available enzymatic models with regard to real conditions of digestion in the gastrointestinal tract.     

Nutrition, energy consumption and various health status indicators in women engaged in intellectual work

A study was made of factual nutrition, energy consumption and the disease incidence among women teachers and research workers. The diets of these women were marked by excess caloric value (16-21% above normal) at the expense of high protein consumption (15-30% above normal), including animal proteins (20-40% above normal), total fats (14-40% above normal) and carbohydrates (11-22% above normal) and by the lack in the diet of vegetable fats, vitamins A and C, and calcium. Analysis of the disease incidence demonstrated that 16% of the women suffer from cardiovascular diseases, 5% from gastrointestinal diseases, 17% from overweight and 20% from obesity.     

Effect of ruminal protein degradation of blood meal and feather meal on the intestinal amino acid supply to lactating cows

Four lactating cows fitted with ruminal cannulae and T-type cannulae in the proximal duodenum and terminal ileum were utilized to measure protein degradation in the rumen and amino acid flow to and absorption from the small intestine. Soybean meal, blood meal, feather meal, and a 50-50 combination of blood meal and feather meal provided 50% of the protein in diets that contained 50% grain mix, 40% corn silage, and 10% alfalfa pellets on a DM basis. Ruminal degradation of dietary CP was 53, 43, 32, and 37% for diets containing soybean meal, blood meal, feather meal, and the combination of meals. Cows fed the latter two diets also had lower ruminal NH3 concentrations and efficiency of bacterial protein synthesis compared to those fed the soybean meal diet. Total tract N digestibility was lower for diets containing feather meal (63.4%) and a combination of meals (66.3%) than the soybean meal diet (78.5%). Total amino acid flow to the duodenum was 19.3 and 15.6% higher for cows fed the feather meal and combined meal diets, respectively, compared with the soybean meal diet. Total amino acid absorption from the small intestine was higher as well as absorption of individual amino acids for the combined meal diet compared with the soybean meal diet. Absorption of individual amino acids, expressed as a percentage entering the duodenum, was lowest for the feather meal diet. Results from this study show that feeding a combination of blood meal and feather meal instead of soybean meal can increase intestinal supply and absorption of amino acids in dairy cattle.     

Effects of dietary fibre extracts on calcium absorption in the rat

The effects on calcium absorption of several fibre extracts (which differed greatly in their chemical compositions, phytate concentrations, and proportions of soluble and insoluble fibre) and of phytate, as sodium phytate, were investigated in rats. Samples of fibre from apple, orange, pea, sugarbeet, barley and wheat were obtained from Sofalia (France). Calcium absorption (using a ⁴⁷Ca tracer method) in 9-week-old rats from a purified diet, containing fibre at a level of 50 g/kg, was reduced by wheat and wheat-TDF fibre preparations and was unaffected by apple, orange, pea, sugarbeet, barley, pectin and guar gum, compared to the cellulose-containing diet. Calcium absorption was also reduced by increasing phytate concentration in the range 0 to 30 mmol/kg diet. Overall, the results suggest that calcium absorption is not affected by fibre components per se, (i.e. indigestible polysaccharides) and that the reduction in calcium absorption observed with wheat and wheat-TDF fibres is due to their phytate contents.     

Ruminal fermentation and nutrient digestion by dairy cows fed varying amounts of soyhulls as a replacement for corn grain

Five multiparous Holstein cows cannulated in the rumen and duodenum that averaged 63 d in milk were used in a 5 x 5 Latin square design with 14-d periods to evaluate the incremental substitution of soyhulls for corn in the diet. Diets contained 23% alfalfa silage, 23% corn silage, and 54% concentrate on a dry matter (DM) basis. Pelleted soyhulls replaced corn in the concentrate to supply 0, 10, 20, 30, or 40% of the dietary DM. The intakes of DM and organic matter were unaffected by treatments. Intakes of acid detergent fiber and neutral detergent fiber increased linearly, but the intake of nonstructural carbohydrates decreased linearly as soyhulls increased from 0 to 40% of dietary DM. The amount of acid detergent fiber and neutral detergent fiber digested was increased whereas the amount of nonstructural carbohydrate digested was decreased in the rumen, in the lower digestive tract, and in the total digestive tract as soyhulls replaced corn in the diet. Passage to the duodenum of nonammonia N, microbial N, nonammonia nonmicrobial N, total essential amino acids, total nonessential amino acids, and total amino acids were not affected by treatments. Yield of milk (29.5 kg/d) was not affected by treatments in this experiment. In a companion experiment, cows fed the 40% SH diet produced 1.2 kg/day per cow less (P < 0.07) milk than cows fed the control diet which is similar to the 1.3 kg/day per cow less milk produced by cows fed the same 40% SH diet in this experiment. Differences in the source of energy (fiber vs. nonstructural carbohydrates), in the amount of fiber and nonstructural carbohydrates digested, and in the site of digestion in the gastrointestinal tract may cause a shortage of the source and/or amount of energy that is required for maximum milk production in high producing cows when more than 30% of the dietary DM that is supplied as corn is replaced with soyhullss.     

Importance of the qualitative composition of dietary proteins in the dietotherapy of ischemic heart disease patients

The effects of two isocaloric antiatherosclerotic diets (containing 120 g protein) differing in the amino acid composition of protein sources introduced were studied and compared in patients with coronary heart disease. Conventional protein sources were used in the first diet, whereas in the second diet, 15% of protein (by weight) was replaced by soybean protein isolate. A study was also made of the effect of dietetic management on lipid metabolism in blood serum. Hemocoagulation, capillary permeability, the kallikrein-kinin system, and immune responsiveness. An increase in the hypolipidemic effect of the diet was noted together with a decrease in the activity of the kallikrein-kinin system, capillary permeability, and body autosensitization upon introduction into the diet of soybean protein isolate. The increase of the protein quota as well as that attained by means of introducing in the diet of soybean protein isolate reduces the therapeutic effect of the diet on hemostasis.     

Calcium bioavailability of vegetarian diets in rats: potential application in a bioregenerative life-support system

Calcium bioavailability of vegetarian diets containing various proportions of candidate crops for a controlled ecological life-support system (CELSS) was determined by femur 45Ca uptake. Three vegetarian diets and a control diet were labeled extrinsically with 45Ca and fed to 5-wk old male rats. A fifth group of rats fed an unlabeled control diet received an intraperitoneal (IP) injection of 45Ca. There was no significant difference in mean calcium absorption of vegetarian diets (90.80 +/- 5.23%) and control diet (87.85 +/- 5.25%) when calculated as the percent of an IP dose. The amounts of phytate, oxalate, and dietary fiber in the diets did not affect calcium absorption.     

Influence of nano-size reduction on absorption and bioavailability of calcium from fortified milk powder in rats

The present study aimed to investigate the effects of fortification and nano-size reduction on absorption and bioavailability of calcium from the fortified milk in ovariectomized (OVX) and OVX-osteoporosis rats. The main goal was to determine the effect of daily consumption of experimental diets on serum calcium, feces calcium, bone calcium, bone breaking strength and bone morphology among rats. This study was conducted to optimize the preparation of nano-fortified milk powder. Then, the calcium bioavailability in 64 female OVX rats and OVX-osteoporosis rats was investigated. The results revealed that bone breaking strength (maximum load) and bone calcium increased with consumption of nano-fortified diet compared with fortified diet. The same observations were seen for bone morphology. OVX rats exhibited higher calcium bioavailability and absorption than OVX-osteoporosis rats with regard to fortified and nano-fortified diets. The amount of calcium absorption from fortified and nano-fortified milk powders in OVX rats was 63.54% and 89.06%, respectively. The bioavailability of calcium from fortified and nano-fortified milk powders in OVX rats was 24.64% and 41.65%, respectively. Moreover, the calcium bioavailability (%) from fortified and nano-fortified milk powders in OVX-osteoporosis rats was 9.74% and 30.17%, respectively. In OVX-osteoporosis group, the absorption levels of calcium from the same experimental diets were 60.54% and 89.09%, respectively.     

Preservation of the enzyme activity of horseradish peroxidase administered into the gastrointestinal tract of adult dogs and rats

Enzymatic activity of horse radish peroxidase administered to the gastrointestinal tract of adult dogs and rats was assessed. It was discovered that in adult dogs, 30% of the protein reached the distal parts of the small intestine in a non-splitted form. As early as two hours after administering horse radish peroxidase over 15% of active enzyme was detectable in the gastrointestinal tract of adult rats. 0.5% of non-splitted enzyme was found in the rat large intestine.