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S Huszár

Publications and source records attributed to S Huszár.

6 recordsLinked to original sources
PubMed2001

Absorption of inorganic, trivalent and hexavalent chromium following oral and intrajejunal doses in rats.

The intestinal absorption of trivalent and hexavalent chromium (Cr) given orally (experiment I) or infused in the intestine (experiment II) was investigated in rats. The nonabsorbable form of chromium (51Cr2O3) and water-soluble and more absorbable Na2(51)CrO4 (the hexavalent form of Cr) were compared. Total retention of chromium given orally ranged around 15 percent of the dose, regardless of the chromium compounds applied. The absorption rate of chromic oxide, which is considered a nonabsorbable compound, was 14.4 as a percentage of chromium intake. This result indicates that some loss of chromium has to be taken into account in metabolic trials made by the indicator method. In isolated rat intestine, from the injected Cr 2.5% of chromic oxide and 43.2% of sodium chromate were absorbed during an hour (experiment II). The absorbed chromium was transferred to the liver where the liver tissue retained 10.9% of chromic oxide and 51.1% of sodium chromate. Radioactivity of v. cava caudalis following intestinal injection of Na2CrO4 was thirtyfold greater than after Cr2O3 dosing. This phenomenon can be explained by the lower blood clearance of chromate. Different absorption rate of chromate depending on the route of administration could be due to the fact that the hexavalent form given orally was reduced to Cr3+ in the acidic environment of the stomach. When Na2CrO4 was infused directly in the intestine of rats, such reduction could not occur. This means that the acidic gastric juice might play a role in inhibiting the intestinal absorption of Na2CrO4 when this compound is given orally.

Administration, Oral↗
PubMed2000

Effects of dietary protein and carbohydrate source on rumen fermentation and nutrient flow in sheep.

The effects of decreasing levels of rumen degradable protein (RDP) and nonstructural carbohydrate (NSC) (Diet 1: 74% RDP and 38% NSC; Diet 2: 57% RDP and 32% NSC; Diet 3: 48% RDP and 23% NSC) were studied in cannulated sheep. Total volatile fatty acid (VFA) content rose in response to increasing NSC content. The molar ratio of acetate to propionate was the narrowest for Diet 1. Ruminal concentrations of ammonia and urea increased in response to the rising level of RDP. Flow of organic matter (OM) to the duodenum was increased for Diet 3, which resulted in the lowest apparent and true ruminal digestion of OM. Duodenal flow of total nitrogen (N) increased as RDP content decreased. The highest quantity of undegraded feed protein in duodenal digesta was measured in sheep fed Diet 3. Microbial N flow and microbial efficiency were unaffected by the diets. These results indicate that an NSC level lower than 25% and an RDP content lower than 50% did not exert any negative effect on microbial N production. This phenomenon supports the theory that if the level of RDP is lowered with a concomitant decrease in NSC, uncoupled fermentation cannot be observed.

Animals↗
PubMed1996

Evaluation of the digestibility of nutrients in pigs by ileal cannulation technique.

A simple T-cannula was surgically inserted into the ileum of growing female Large White x Dutch Landrace swine. Chymus samples collected with the help of the cannula were analysed to determine the apparent digestibility of different dietary nutrients such as dry matter, crude protein and starch, as well as of some essential amino acids. The following three experiments were conducted: (I) of the cereals, the "Tewo" triticale variety fed alone and in 1:1 concentrate mixtures with wheat or maize was studied; (II) waxy maize hybrids and maize hybrids of normal endosperm were compared without treatment and after treatment by the Bocchi technology; (III) untreated and extruded maize supplemented either with extracted soybean or with extracted sunflower was also tested. The ileal digestibility of protein, amino acids and starch was determined and compared with values obtained by conventional (faecal) analysis. When feeding triticale alone or in combination with wheat or maize, the ileal digestibility of crude protein and amino acids increased as a result of feeding the cereal combinations (e.g. crude protein 72-79%, lysine 75-79%, threonine 63-78%, methionine 74-86%). Comparison of the two maize hybrids revealed that, with the exception of methionine, lysine and tyrosine, the amino acids of the waxy hybrid had higher ileal digestibility. Treatment of the normal hybrid by the Bocchi technology caused a significant improvement in the ileal digestibility of cystine, isoleucine, lysine, valine, and dry matter. This treatment also improved the faecal digestibility of all test nutrients but methionine. Bocchi treatment of the waxy hybrid significantly improved the ileal digestibility of isoleucine, leucine, methionine, tyrosine and valine, and the faecal digestibility of cystine, dry matter, and crude protein. No major variety- or treatment-related differences were found in the digestibility of starch. As a result of extrusion, the digestibility of nutrients of the soybean + maize mixture increased from 61.6% to 70.3% (crude protein), from 41.1% to 59.4% (threonine), from 60.1 to 72.0% (methionine), and from 70.7% to 82.7% (lysine). The same treatment of the sunflower + maize mixture increased the digestibility of crude protein from 80.6% to 84.5%, that of threonine from 78.1% to 80.6%, that of methionine from 79.7% to 84.3%, while that of lysine from 61.4% to 72.3%. The ileal digestibility of starch was 97-98% for both mixtures. As a result of extrusion, most of the faecal digestibility values showed a significant improvement for both the soybean- and the sunflower-containing mixtures. The favourable effect exerted by extrusion on the digestibility of nutrients is markedly influenced by the feed components.

Amino Acids↗
PubMed1995

Effect of avoparcin on rumen fermentation and duodenal nutrient flow in sheep.

In a digestive-physiological experiment series, the effect exerted by avoparcin on rumen fermentation and on the ruminal digestion of nutrients was studied in wethers provided with rumen and duodenal cannulas, as a function of the composition of feed as substrate. Three control (I, II, III) groups containing different amounts of rumen degradable protein (RDP) and nonstructural carbohydrate (NSC) were formed (composition of diet: group I, 74% RDP and 38% NSC; group II, 57% RDP and 32% NSC; group III, 48% RDP and 23% NSC). The feeding of control diets was followed by the administration of experimental diets containing avoparcin (groups I+A, II+A, and III+A). The dose of avoparcin was 0.75 mg/kg body weight. Irrespective of the RDP and NSC content of the feed, avoparcin reduced the molar ratio of acetic acid and increased that of propionic acid, decreased the acetic acid/propionic acid ratio, and increased the molar ratio of isobutyric acid. Ammonia concentration of the ruminal fluid was significantly lower in group I+A than in the corresponding control group (I). Avoparcin supplementation of diet III improved the apparent digestibility of organic matter from 52.9% to 56.4%. When added to a ration of high NSC and RDP content (I), avoparcin decreased the true digestibility of organic matter from 77.0 to 72.5%. Compared to diet III as well as to diets II and III, avoparcin significantly increased the ruminal degradation of cellulose and hemicellulose, respectively. Avoparcin supplementation of the diet significantly decreased the microbial N content of the duodenal chymus irrespective of the NSC and RDP content of the diet. In group I+A, the amount of dietary N passed from the rumen into the duodenum in 24 h was significantly higher (7.1 g/day vs. 2.7 g/day). In wethers fed the diet of the lowest NSC and RDP content (III), avoparcin supplementation (III+A) increased the apparent digestibility of N in the rumen. In contrast, in wethers fed diets of higher RDP and NSC content (I and II) the true ruminal digestibility of N decreased. Irrespective of the RDP and NSC content of the diet, avoparcin supplementation significantly reduced the efficiency of microbial protein synthesis. The enhanced propionic fermentation induced by the administration of avoparcin allows more efficient utilization of the dietary energy. The higher ratio of undergraded, bypass protein reaching the duodenum provides the animal with a protein source degraded and utilized directly in the small intestine. The results support the observation that avoparcin increases the body weight gain of animals during fattening.

Animal Feed↗