Natural levels of lead, cadmium and mercury in tissues and hair of newborn calves from different areas of Czechoslovakia.

Liver, kidney, muscle and hair samples from newborn, born-dead or found-dead calves were collected within 10 days after parturition, for the determination of Pb, Cd and Hg levels. Differential pulse anodic stripping voltammetry at the static mercury dropping electrode was used for Pb and Cd determination after dry ashing of the samples. Cold-vapour atomic absorption spectrometry was used for direct Hg determination. The aim of the study was to monitor background Pb, Cd and Hg levels in vital and important tissues of newborn calves in which nutritional influence was negligible. Three geographic areas in Czechoslovakia were monitored (A, B and C). The following ranges of mean values for all animals were obtained (mg kg-1, wet wt): Pb--muscle (0.04-0.25), liver (0.10-0.29), kidney (0.05-0.43), hair (0.11-0.55); Cd--muscle (0.007-0.038), liver (0.008-0.073), kidney (0.007-0.062), hair (0.009-0.074); Hg--muscle (0.002-0.071), liver (0.005-0.18), kidney (0.004-0.50), hair (0.07-0.77). The value obtained for heavy-metal levels (Pb, Cd, Hg) indicated that there is a significant difference between the groups of found-dead and slaughtered calves from the Nymburk region (muscle--Pb, Cd; liver--Pb; kidney--Pb, Cd). Unexplained high Hg levels in hair samples were measured in the Hradec Králové region.

The occurrence of aflatoxins in peanuts imported into Czechoslovakia for human consumption.

Results of 492 analyses for aflatoxin in raw shelled peanuts imported into Czechoslovakia during 1982-1984 are presented. Most samples (55.3%) had aflatoxin content less than the detection limit of the radioimmunochemical screening method (0.8 micrograms/kg). Further analyses showed that 239 out of 410 samples of roasted peanuts contained aflatoxin below the detection limit. Only 1.9% of all peanut samples were found to have contamination level more than 5 micrograms/kg aflatoxin. The highest levels of aflatoxin observed were in a raw peanut sample containing 202.1 micrograms/kg and in a roasted peanut sample containing 32.6 micrograms/kg.

[Experimental modification of the resorption process and lead deposition in the body of the domestic duck]. / Studium der experimentellen Beeinflussung des Resorptionsprozesses und der Bleideposition im Organismus der Hausenten.

In an experiment with 40 domestic ducks (Peking White breed) being 40 days old, it was shown that the process of lead resorption and deposition was neither significantly modified by different kinds of therapy nor by changes of food composition. A single dose of 30 lead small shot given to the experimental animals resulted after 1 week in a significant increase of lead concentration in liver (4.32 mg/kg-1), kidney (11.36 mg/kg-1) and muscle tissue (1.15 mg/kg-1) as compared to the values of control animals (liver 0.07, kidney 0.11 and muscle 0.06 mg Pb/kg-1). After 3 weeks with different types of therapy and feeding of experimental diets, i.e. at the end of the experiment, no significant differences in liver, kidney and muscle lead concentrations between the control and experimental animals could be found.

[Experimental control of the process of lead absorption and deposition in domestic ducks]. / Experimentální ovlivnení procesu vstrebávání a depozice olova v organismu domácích kachen.

A trial was conducted with 40 domestic ducks of the White Pekin breed at the age of 40 days: thirty pieces of lead shot were introduced as a single dose in the gizzard. The process of lead resorption and deposition was found not to be significantly influenced by the therapeutic treatments nor changes in the composition of feed. A week after the administration of shot a significant increase was recorded in the content of lead to 4.32 mg in liver, to 11.36 mg in kidney and to 1.15 mg in muscle (the respective values for the control animals were 0.07, 0.11 and 0.06 mg per kg). At the end of the trial after three weeks of treatment and administration of experimental diets, no significant differences were recorded in lead content in liver, kidney and muscle between the untreated and treated ducks nor ducks fed experimental diets.

[Dynamics of abrasion of lead pellets in the gizzard of domestic ducks]. / Dynamik des Abschleifens von Bleischrotkörnern im Muskelmagen der Hausenten.

Experiments were made with 6 control and 6 experimental ducks. 10 lead shot were given for once into the gizzard of the experimental animals. During a period of 6 days, changes of the form of the grains of shot, the ALAD-activity, the hematocrit and the hemoglobin have been examined. Finally, significant changes of the form as well as the surface of the lead shot could be seen. The average loss of mass of one grain of shot in 24 hours (former mass 0,15 g) came up to 0,01 g. Already 24 hours after the ducks had received the grains of shot, the ALAD-activity decreased from 70,07 to 5,43 U/l-1. As far as the hematocrit and the hemoglobin are concerned, compared with the control ducks, there were no important differences.

[Relation between glycemia, serum ascorbic acid, and weight gains in calves in large barns]. / Závislost mezi glykémií askorbémií a hmotnostními prírustky u telat ve velkokapacitním teletníku.

In the period from acceptance to the large-scale calf-house to six months of age, 42 calves (20 bullocks and 22 heifers) were studied for the dependence between the dynamics of glycaemia, ascorbaemia, and weights and weight gains. In both sexes, the highest level of glycaemia was obtained at the age from 14 to 21 days (kappa = 5.3 mmol.1(-1)). This high level was followed by a gradual decrease which resulted in the statistically significantly lowest average level at the age of six months (2.0 mmol.1(-1)). In heifers the level of glucose decreased to 1.7 mmol.1(-1) in the fifth month; in bullocks the values were significantly higher at this age (2.8 mmol.1(-1)). The values were subjected to correlation analysis and regression analysis, but no statistically significant dependence was found between weight gains and the levels of glycaemia, either in heifers or in bullocks. Higher coefficients of correlation were only found between the weight of the calves when accepted to the calf-house and the level of glucose. The ascorbaemia of the calves of both sexes at the age from the 7th to the 11th week ranged from 59.1 to 79.5 mumol.1(-1); from the fourth month of age it decreased conspicuously, the lowest values being obtained in the fifth month (22.7 mumol.1(-1)) when the values of vitamin C in the blood serum of heifers (11.4 mumol.1(-1)) were lower than in the bullocks. The correlations between the weight gains and ascorbaemia were statistically significantly negative in the bullocks between the second and 22nd week of age.

[Dynamics of urea concentration in blood cells of the domestic fowl during early post-incubation ontogenesis]. / Dynamika koncentrace mocoviny v krvinkách kura domácího v casné postinkubacní ontogenezi.

Urea was determined by means of diacetyl monoxim in the blood cells of 80 cockerels of the initial breed White Leghorn, commercial hybrid Primant. The highest urea concentration was ascertained on the 15th day of life: 392.33 +/- 85 mg per 10(12) blood cells. The content of urea in the blood cells irregularly deceased with the age of the cockerels. The minimum urea concentration was obtained on the 40th day of post-incubation life: 63.40 +/- 56.5 mg per 10(12) blood cells.

[Dynamics of urea concentration in cockerels during the 1st month of life]. / Dynamika koncentrace urémie kohoutku v prvním mesíci zivota.

The concentration of urea in the blood serum of 190 cockerels (The Primant commercial hybrid) was determined by means of diacetylmonoxim (Homolka, 1971). Uremia reached values from 0 to 23.20 +/- 5.29 mg per 100 ml. A high individual variability of uremia was found.

[Circadian rhythmicity of urea concentration in the liver and blood serum of cockerels]. / Cirkadiánní rytmicita koncentrace mocoviny v játrech a krevním séru kohoutku.

The circadian rhythmicity of urea concentration was studied in 70 12-day-old cockerels (the Primant commercial hybrid). Urea in the liver homogenate supernatant and in the blood serum was determined by means of diacetylmonoxim (Homolka, 1971). The cockerels were killed in four-hour intervals. Urea concentration in the liver reached its peak at 15.30 o'clock (123.36 +/- 6.32 in conversion to wet tissue or 0.308 +/- 0.01 mg of nitrogen per 100 mg). The circadian rhythmicity of uremia generally coincided with the rhythmicity of urea in the liver.

[Serum and liver lipase activity in chickens during the 1st month of life]. / Aktivita sérové a jaterní lipázy u kura v prvním mesíci zivota

Method according to DIRSTINE (1968) was employed to study the activities of serum and liver lipase in White Leghorn cockerels during early post-incubation ontogenesis; as to serum lipase, two embryo intervals were also studied (the 13th and 20th day of incubation). From the average value of 4.4 ummol (13th day), serum lipase activity increased to the average value of 7.5 ummol (20th day). The first day after hatching the average value was 3.5 ummol which remained almost unchanged until the 9th day, with the exception of a slight drop the third day; an increase of activities was observed on the 13th day (4.9 ummol), 15th day (3.5 ummol), 21st day (7.6 ummol), 22nd day (5.5 ummol), and 24th day (8.8 ummol). The minimum average activity of 2.5 ummol was measured the 32nd day. Liver lipase activity was observed to drop from the first-day starting value of 20.6 ummol to 9.8 ummol (the second day), with a subsequent increase to 14.9 ummol (the 4th day). The maximum values were recorded the 13th day (26.2 ummol) and the 15th day (28.7 ummol) whereas the minimum average value was obtained the 32nd day (6.3 ummol). Liver lipase activity drop on the second day of age and serum lipase activity drop on the third day with subsequent increase are probably associated with the change from yolk-sac nutrition to feeding per os. Some stabilization of serum and liver lipase occurs the 32nd day; the values found in adult fowl were almost the same as the 32nd day values.