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Biomedical subjects

J Kovácik

Publications and source records attributed to J Kovácik.

6 recordsLinked to original sources
PubMed1999

Distribution of cadmium in selected organs of mice: effects of cadmium on organ contents of retinoids and beta-carotene.

Cadmium was administered to 32 adult ICR mice i.p. in two single doses (0.25 and 0.5 mg CdCl2, per kg of b.w.). After 48 hours concentrations of cadmium in kidneys, liver, spleen, muscle (m. quadriceps femoris), ovaries and testes and the concentration of retinyl palmitate, retinol and beta-carotene in kidney, liver and testes were determined. Significantly higher cadmium concentration was found in liver, kidney and ovary in both experimental groups in comparison with the control group (p<0.001). In muscle, spleen and testis the cadmium level was higher, however not significantly. No significant differences in the concentration of retinyl palmitate, retinol and alpha-carotene in liver were found. Concentration of alpha-carotene in kidney and testis was significantly decreased in both groups administered with cadmium (p<0.001). Concentration of retinyl palmitate was significantly lower in testis in the group with higher cadmium level (p<0.001) and the concentration of retinol significantly decreased in kidney and testis of mice after an administration of 0.5 mg CdCl2/kg b.w.

Animals↗
PubMed1994

Evaluation of acid-base disorders in dairy cows using principal component analysis and empiric equations.

Acid-base disorders were studied in two groups of dairy cows. According to conventional interpretation in the 1st group of dairy cows (n = 10) the results of the acid-base parameters indicated respiratory alkalosis and in the 2nd group (n = 10) metabolic acidosis. The data of the two groups were examined using principal component analysis. So called "reduced variables"--principal components for each animal were calculated. Each experimental animal was projected in the coordinates of 3 principal components K1, K2 and K3. The components K1, K2 and K3 comprised a 90% data variability. The importance of variables for a dividing of groups (1 and 2) was quantified. The most important were pCO2, (HCO3)' and BE. It was proved according to mathematico-empiric equations that dairy cows of 1st group suffered from acute respiratory alkalosis. In the 2nd group of dairy cows the combined acid-base disorder was confirmed using the equations for metabolic acidosis and chronic respiratory acidosis. The use of PCA method and empiric equations for acid-base imbalances shows the possibilities for gaining new knowledge how to make the diagnostic process more exact.

Acid-Base Imbalance↗
PubMed1990

[Insulin and thyroxine levels in dairy cows during lactation and after a 9-day fast].

The aim of the study was to observe the effect of longer fasting of dairy cows during lactation on the insulin and thyroxine levels in blood serum. The test was performed at the Research Institute of Animal Production, Nitra. The blood samples for determination of the hormone levels were collected in the morning from the vena jugularis of four fasted 4-5-year-old dairy cows of the Black Pied breed during lactation with an average daily performance of 16.91. The blood was collected on the first, fifth, sixth, seventh, eight and ninth day (fasting) and then on the fifteenth and twenty first day of the test (feeding). The insulin level in the blood serum of fasted dairy cows was more or less balanced till the seventh day of fasting, and ranged from 4.33 to 4.91 microU.ml-1. On the last two days of fasting, the insulin level increased up to 7.11 microU.ml-1 on the 9th day of fasting. The insulin level was significantly higher during feeding than during starvation. The thyroxine level was statistically significantly lower in fasted dairy cows. Increasing insulin level at the last two collections of the fasting period was probably closely connected with the shifting of the endocrine balance from dominant position of insulin to the dominance of the growth hormone and glucocorticoids. A comparatively high effect on the increase of the insulin level was exerted during that time also by the increasing amounts of non-esterifed fatty acids. Starvation significantly reduced the levels of the studied hormones in dairy cows during lactation.

Animals↗
PubMed1986

[Blood levels of nitrogenous substances in dairy cows with high and low production].

In blood serum of dairy cows of the Slovak Pied breed with high and low performance, the levels of total protein, urea, amino nitrogen, non-protein nitrogen and uric acid were studied over the period of four to six weeks after calving. Total protein was determined by the Bio-La-test, amino nitrogen by means of ninhydrin, non-protein nitrogen by Berthelot agent and uric acid by Benedict agent. In comparison with dairy cows with low performance, the dairy cows with high performance had a statistically significantly higher level of total protein, urea, amino nitrogen and non-protein nitrogen. The differences in uric acid content were statistically insignificant.

Animals↗