Study of soil-plant (potato and beetroot)-animal cycle of nutritive and hazardous minerals in a rabbit model.

Potato and beetroot were grown on soils previously treated with heavy metal salts. Each particular microelement had a high concentration in both potato and beetroot [cadmium (Cd) 3.7 and 55.4, lead (Pb) 8.1 and 3.0, and mercury (Hg) 5.8 and 6.8 mg/kg dry matter, respectively]. In a metabolic balance trial 16 New Zealand White rabbits were fed 50 grams of basal diet and potato or beetroot ad libitum. The apparent digestibility of major nutrients and the accumulation of the microelements in different organs were investigated. Both potato and beetroot samples of high Pb and Hg content had the significantly (p < 0.05) lowest digestibility of organic matter and nitrogen-free extract. The Cd ingested from both potato and beetroot accumulated in the kidneys and liver (2.85 and 1.48 as well as 0.459 and 0.265 mg/kg, respectively). All the microelements (Cd, Pb and Hg) accumulated in the testicles (0.196, 0.32 and 0.199 mg/kg, respectively), reducing the rate of spermatogenesis. The tissue retention of heavy metals depends not only on the element itself, but also upon the 'carrier' feedstuff.

Study of the soil-plant (carrot)-animal cycle of nutritive and hazardous minerals in a rabbit model.

Carrots were grown on soils polluted by heavy metal salts. Each particular microelement reached a high concentration [molybdenum (Mo) 39.00, cadmium (Cd) 2.30, lead (Pb) 4.01, mercury (Hg) 30.00, and selenium (Se) 36.20 mg/kg dry matter] in the carrot. In a metabolic balance trial conducted with 15 male and 15 female New Zealand White rabbits, the control animals (n = 5) were fed ad libitum with concentrate as basal diet, while the other rabbits received the basal diet and carrots containing the particular microelement. Blood samples were taken to determine the activity of serum enzymes. To investigate the metabolism of Mo, Cd, Pb, Hg and Se, samples were taken from the heart, liver, lungs, kidneys, spleen, ovaries/testicles, entire digestive tract, adipose tissue, femur, hair, faeces and urine. Carrot had significantly higher digestibility for all nutrients than the rabbit concentrate. Carrot samples of high Pb content had the lowest digestibility of crude protein. The microelements differed in their rate of accumulation in the organs examined: Mo and Cd accumulated in the kidneys, Pb in the kidneys, liver, bones and lungs, Hg in the kidneys and liver, while Se in the liver, kidneys and heart. The proportions of microelements eliminated from the body either via the faeces and urine (Mo 80.18% and Se 47.41%) or via the faeces (Cd 37.86%, Pb 66.39%, Hg 64.65%) were determined. Pathohistological examination revealed that the rate of spermatogenesis was reduced in the Mo, Cd, Pb and Hg groups compared to the control. Lead, Cd and Hg intake resulted in a considerable decrease in gamma-glutamyltransferase (GGT) and in an increase of alkaline phosphatase (ALP) activity because of damages to the kidneys and bones. All experimental treatments decreased the activity of cholinesterase (CHE) because of lesions in the liver.

Comparison of the protein patterns of Erysipelothrix rhusiopathiae strains by SDS-PAGE and autoradiography.

The proteins of 12 Erysipelothrix rhusiopathiae strains were radiolabelled with L-[35S] methionine, and the protein fractions were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and autoradiography. The strains were found to differ from each other in their protein patterns; thus, it was concluded that the method applied could provide useful data for the identification of strains. The described procedure was used for determining the percentage contents of protein fractions of identical molecular mass within the strains compared. The results show that there is no significant correlation between the type of the strains and the percentage of identical molecular weight fractions.

Complex study of the physiological role of cadmium. IV. Effects of prolonged dietary exposure of broiler chickens to cadmium.

A 274-day long cadmium (Cd) feeding trial was carried out with broiler cockerel chickens. The diet of the control group (Cd-0, n = 6) contained no added Cd, whereas to the diet of group Cd-25 and group Cd-75 (n = 10 each) 25 ppm and 75 ppm Cd was added, respectively, in the form of CdSO4. The chickens were subjected to examinations described in detail earlier (Bokori et al., 1995b). In addition, the relative mass of five different organs (heart, liver, testis, spleen and brain), expressed as % of the body mass, was also determined. The clinical, gross and histopathological examinations and the assay of organs for mineral element content led to the following main findings. The feeding of diets containing 25 or 75 ppm Cd for more than 9 months did not cause signs indicative of acute Cd toxicosis or mortality in either group. The body mass gain of group Cd-75 chickens markedly decreased. Prolonged Cd exposure of the cockerels increased the relative mass of the liver and heart and markedly decreased that of the testes. The change in mass was proportional to the Cd load. The Cd-fed chickens developed focal pathological fatty infiltration of the liver, histiocytic infiltration of the jejunal mucosa and focal lympho-histiocytic interstitial infiltration and fibrosis of the kidney, which supports the view that prolonged Cd exposure leads to the development of subacute-chronic tissue changes in the kidney. The Cd content of the organs increased by one to three orders of magnitude, in direct proportion to the Cd load. The Cd content of most organs was 2 to 3 times as high as the value reported for broilers exposed to a similar Cd load lasting for 68 days (Bokori et al., 1995b). This indicates that the degree of Cd accumulation is markedly influenced by the duration of the Cd exposure. The highest Cd content was demonstrated in the kidney (724 mg/kg of dry matter). The Cd exposure markedly lowered the Zn, Mo and B content of the bones and the Ni content of the myocardium.

Complex study of the physiological role of cadmium. II. Effect of cadmium load on the cadmium content of eggs.

The possibility of "cadmium (Cd) contamination" of eggs and the dynamics of Cd accumulation were studied. A total of 40 (4 x 10) Japanese quails weighing 155-200 g, being at the middle phase of egg production and kept on batteries in a climatized animal house were used. The birds were fed a standard quail layer diet and drank tap-water ad libitum. With the exception of the control group (Cd-0), the diet of the other three groups was supplemented with Cd sulphate homogeneously mixed in the diet so that it contained 75 mg (Cd-75), 150 mg (Cd-150) and 300 mg (Cd-300) per kg. During the 37-day feeding trial the quails' behaviour, health status and daily egg production were monitored and the birds were weighed weekly. The egg production of the experimental groups, particularly of those exposed to a high Cd load, rapidly decreased: at the highest Cd load (300 ppm) egg production completely ceased at days 10-11 of the trial. The total Cd content of the eggs rose already from the 3rd day of the feeding trial and by day 10 it reached a value of 0.777 mg/kg dry matter in the eggs of quails of group Cd-75. This was about five times the value measured in the control quails' eggs (0.165 mg/kg dry matter). The Cd content of the egg-white and egg-yolk (maximum values: 0.212 and 0.107 mg/kg dry matter) also increased to about 2 or 3 times that measured in the control eggs. The Cd content of eggs reached the peak in the 2nd week of the feeding trial, then started to decrease, and in the 3rd and 4th weeks not even the eggs laid by quails exposed to a high Cd load contained more Cd than about twice the concentration measured in the controls' eggs. The elucidation of this hitherto not studied process requires further investigations. The phenomenon may be due to a lack of the protein necessary for Cd transport and to the impairment of Cd absorption and of the excretory activity of the oviduct. The higher Cd concentrations measured in the egg were accompanied by markedly elevated Fe, K and S values. In the egg samples collected in the 4th week a substantial reduction in Ca and P concentration was observed. As regards the mineral elements measured in the egg-shell, a significant negative correlation was established between the concentration of Cd and those of Zn, Mg and Ca.(ABSTRACT TRUNCATED AT 400 WORDS)

Complex study of the physiological role of cadmium. III. Cadmium loading trials on broiler chickens.

Cadmium (Cd) loading trials were conducted on a total of 110 (3 x 10 and 4 x 20) broiler chickens prereared for 21 days. The control chickens received no cadmium, while chickens in the six treatment groups were given different doses of Cd as an aqueous solution of CdSO4 administered either into the crop or mixed in the feed. The chickens were kept in a climatized animal house and treated usually for 3-5 weeks (maximum 68 days), with the exception of group Cd-75 chickens which were treated up to 239 days of age. The chickens' health status, body mass and feed consumption were monitored throughout the trial. On days 14-20 and on day 42 of the trial 2 chickens per group, then at the end of trial a total of 25 chickens were killed in anaesthesia. These birds, together with chickens that died or were killed during the trial, were subjected to detailed gross pathological examination. From 11 organs (kidney, liver, spleen, testicle, brain, myocardium, skeletal muscle, lungs, digestive tract, pancreas, tubular bones) of these chickens samples were taken for assay for a total of 16 elements, as well as for light and electron microscopic examination. With the exception of groups Cd-30 and Cd-600, no abnormal clinical signs were observed in the first two weeks of the trial. Chickens of group Cd-30 died before day 8-12 of the trial among signs of complete anorexia, rapid emaciation, huddling and diarrhoea, while chickens of group Cd-600 died before day 28, showing similar clinical signs. The body mass of chickens fed a Cd-supplemented diet either remained constant or decreased substantially, in a degree proportional to the Cd load. The only exception was group Cd-2.5, in which the average body mass of birds at the end of week 8 slightly exceeded that of the controls. Four out of the 10 cockerel chicks fed a diet containing 75 ppm Cd up to 239 days of age died of intercurrent diseases; the remaining six grew well and reached a body mass of 3.8-4.3 kg. Feed conversion efficiency was satisfactory in the control group and in group Cd-2.5 (2.1 and 2.4 kg, respectively) and could not be evaluated in a realistic manner in the other groups. At necropsy, the cockerel chicks of groups Cd-30 and Cd-600 showed severe emaciation, liver and kidney degeneration, myocardial hypertrophy and cardiac dilatation.(ABSTRACT TRUNCATED AT 400 WORDS)

Effects of long-term aluminum exposure on certain serum constituents in broiler chickens.

The aim of this work was to study the effects of 35 days exposure to aluminium on certain serum biochemical quantities in chickens. Broiler chicks (TETRA-726 hybrid, male) were kept in a climate-controlled stall with feed and water ad libitum, from day 1 of age, for 7 weeks. From the beginning of the third week aluminium was added to the diet as aluminium chloride. Treatments included supplemental aluminium content of 0, 200, 1000 and 3000 mg/kg ration. At the end of the experiment, blood samples were taken from the v. ulnaris. The treated groups showed significantly elevated alkaline phosphatase activities, as well as increased cholesterol concentrations and decreased triacylglycerol concentrations, and these changes were dose-dependent. The concentration of uric acid was significantly higher in the group receiving 1000 mg/kg ration, but significantly lower in the group receiving 3000 mg/kg ration, compared with the controls. In the treated groups, the concentration of glucose, as well as the activities of cholinesterase, aspartate aminotransferase, gamma-glutamyl transferase and creatine kinase were similar in the controls and treated animals. High levels of alkaline phosphatase are due to increased osteoblastic activity, provoked by the disturbance of bone formation, caused in turn by aluminium. Alterations in serum uric acid may be connected with metabolic disturbances (e.g. renal function, cation--anion balance etc.). Neither hepatic nor muscle damage was found.

Complex study of the physiological role of aluminium. II. Aluminium tolerance tests in broiler chickens.

Aluminium (Al) tolerance tests were carried out in 8 x 24 (a total of 192) broiler chickens pre-reared for 17 days. Chickens of the control group were fed a standard poultry grower diet ad libitum, while those in six experimental groups received a diet supplemented with different (200, 500 and 1,000 mg/kg of feed) doses of Al supplied in the form of AlCl3 and, in two cases, with the same dose of P added to the feed in the form of MCP, up to 52 days of age. Chickens of one group were fed a diet containing 3,000 mg Al per kg of feed for 70 days. The acidic pH of AlCl3 solution sprayed onto the feed was neutralized by adding a sufficient amount of NaHCO3 solution in all but one group. The birds' health status was monitored regularly throughout the feeding trial. Their body mass gain and feed consumption were recorded weekly. At the end of the trial, 3-10 chickens per group (a total of 40 birds) were exsanguinated, subjected to gross pathological examination, and samples were taken from 9 organs (liver, kidney, skeletal muscle, myocardium, brain, spleen, testicle, lungs and tubular bones) for light and electron microscopic examination and for the regular determination of 8 elements (Ca, P, Mg, Zn, Fe, Mn, Cu, Al). In addition, samples were taken from the organs of 2-5 chickens per group for analysis for additional 6 elements (Mo, Co, Ni, Sr, Na, K). From the results obtained the following main conclusions were drawn: (i) With the exception of four birds culled during the trial, all chickens remained symptomless throughout, and all chickens except those fed a diet supplemented with 3,000 mg/kg aluminium developed properly. (ii) The body mass of chickens in groups fed a diet supplemented exclusively with Al decreased moderately (by 67, 69 and 88 g, respectively), depending on Al concentration of the diet. Chickens fed a diet containing 3,000 mg/kg Al showed a very substantial (621.3 g; 32%) decrease in body mass Phosphorus supplementation did not markedly affect the body mass gain. (iii) Specific feed utilization was satisfactory (2.100-2.210 g/kg body mass). The very poor feed utilization of chickens subjected to the heaviest Al load can be attributed to the temporary disturbance of acid-base balance caused by the non-buffered AlCl3 solution.(ABSTRACT TRUNCATED AT 400 WORDS)

[Trials to improve the media used for the methyl red reaction (MRT). II]. / Incercari de optimizare a mediilor folosite pentru reactia rosului de methyl (MRT). Nota II.

The evolution of the methyl rot reaction (MRT), expressed by the pH dynamics in the first 18 hours was examined. A medium made of caseine or soya hydrolysate distributed in small volumes, was experimented versus a control broth made of meat peptone (Clark-Lubs). For Klebsiella the results showed that in the control group the pH acidifies and remains low, thus mimicking a positive reaction. In the caseine/soya medium, a decrease of pH at 4-8 hours is first noticed. Initial acidification, consecutive to glucose fermentation, is then counteracted by another type of processes that change the reaction direction. pH increases at 12-18 hours towards neutrality hat can be easily exceeded in 24 hours. Alkaline reversion is favoured by: a--the richer content in aa diaminomonocarboxylic and b--assurance of a large aeration by increase of the ratio between surface and volume. For evidencing realkalinization, characteristic of Klebsiellae, the medium with caseine/soya, including "ab initio" either Bromkresolpurpur (pH = 5.2-6.2) or Bromtimolblau (pH = 6.7-7.6) is experimented. The medium ensures the direct reading of the reaction, at 18-24 hours, by the colour change. The results correspond to metric pH recording. When the results are not clear (slowly metabolic strains), the culture may be reincubated, an important advantage versus the Clark-Lubs procedure.

[The effect of the type of peptone for protein catabolism and realkalinization in Klebsielleae cultures]. / Influenta tipului de peptona pentru catabolismul proteinic si realcalinizarea culturilor la Klebsielleae.

According to the authors of the present paper, the formation of the MR+ and MR- groups is not explained by the variable degree of acidification, but by the various capacity of realkalinization of cultures. pH increases to values tending to 8 due to the formation of amines, ammonia and other basic products. They are the result of oxidative degradation processes, thus explaining the dependence on oxygen and the strictly aerobic character of the reaction. The acid-alkaline variation is influenced by the different content of peptones in monoaminodicarboacylic (meat-contraindicated) and diaminomenocarvoxylic (casein/soya bean-recommended) acids. The alkaline reversion may be determined in liquid media, having included ab initio either bromthymol blue, or bromcresol purple. The changes in pH may be read directly, colorimetrically, after an 18-20-hour incubation. By changing the interpretation (acid from glucose) and the indicator suggested by Clark and Lubs, the name "methyl red" becomes meaningless. At the same time, the introduction of other biochemical parameters (proteinic catabolism, realkalinization, dependence on oxygen) and the modification of the conditions of methods, justify the suggestion that the process of alkaline reversion, noted by the abbreviation "Reval", should be considered as a "per se" reaction and the laboratory determination should be patented as a routine test for the diagnosis of Enterobacteria.

[Aerobic conditions and the dynamics of the methyl red reaction in Klebsielleae]. / Conditionarea aeroba si dinamica reactiei rosului de methyl la Klebsielleae.

The development of the methyl red reaction (MR) in Klebsielleae, analyzed during a 4-day thermostatting, showed important pH-variations. Two steps are distinguished during the reaction dynamics: the former of acidification, common to all Enterobacteriaceae and the latter of alkaline reversion, specific to Enterobacter, Klebsiella, Serratia and other MR germs. The processes determining the alkaline reversion are conditioned by the presence of large amounts of air/oxygen (aerobic processes). In this situation, the lack of oxygen and maintenance of a relative degree of anaerobiosis block realkalinization (media covered with paraffin oil) whereas the large aeration stimulates it (optimum ratio between the large contact surface and a small volume of medium). Alkaline reversion cannot be explained by the more or less intense process of glucose fermentation but by degradations of nitrogenized substances with formation of amines, ammonia, and other basic compounds. That is why the analysis of the reaction mechanism of methyl red has to consider the characteristics of the catabolism of the nitrogenized substances and the intense realkalinization capacity of the culture medium proper to Klebsielleae but poorly expressed and non efficient in Enterobacteriaceae.

Optical parallel Dempster-Shafer calculations.

The Dempster-Shafer formalism allows us to update certainties (both beliefs and plausibilities) by taking into account indications from new knowledge sources. We show here that optical parallel Dempster's rule of combination computation is practical because all operations can be broken up into two which have previously been shown to be ideal for optics: vector outer product formation and spatial remapping. Easily available technologies lead us to a device capable of ~10(5) belief updates per second.