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E Bobáková

Publications and source records attributed to E Bobáková.

13 recordsLinked to original sources
PubMed1986

Testosterone concentration in the seminal plasma of cocks.

Testosterone concentrations in the seminal plasma of cocks ranged from 0.46 to 5.05 ng/ml and were substantially lower than in blood plasma. No significant variation was noted in seminal plasma testosterone concentrations during the light phase of the day, whereas the concentration in blood declined over this period. Spermatozoal concentration and seminal testosterone decreased in the third sample of the semen collected sequentially at 3 h intervals. Testosterone concentrations in seminal plasma (1.57 +/- 0.17 ng/ml) and in the semen from the ductus deferens (1.34 +/- 0.24 ng/ml) were not significantly different.

Animals↗
PubMed1986

[Sexual development and levels of plasma testosterone in the light type of cockerel].

The concentration of testosterone in blood plasma during the ontogenetic development of cockerels was studied in relation to the development of spermatogenic part of gonads. On the basis of the results, sexual development of cockerels can be divided into three stages. The first stage (from hatching to the age of eight to nine weeks) was characterized by a slow increase in gonad weight, by low concentration of plasma testosterone (0.4-2.0 nmol/l) and by the occurrence of spermatogonia in testes. In the course of the second stage (from the age of nine to 16 weeks) a rapid increase in the weight of testes and testosterone concentration was observed. At the end of this stage all phases of spermatogenic cycle were observed in gonads; the testosterone levels averaged to 10 nmol/l. In the course of this stage all cockerels reached sexual maturity; large individual differences in spermatogenesis development were observed. The third stage (16 weeks of age and more) was characterized by an intensive spermatogenesis, further increase in gonad weight and by typical variations of the plasma testosterone levels. The concentration of the circulating testosterone increased before the onset of the final stages of the spermatogenic cycle.

Animals↗
PubMed1983

[The relation between the concentration of testosterone in seminal plasma and certain indicators of reproduction in roosters].

Testosterone concentrations in the semen plasma of the cocks of the laying type were analyzed. The levels in semen plasma were substantially lower than in peripheral blood and were found at the interval of 1.58 to 13.30 nmol . 1(-1), the average values amounted to 5.5 nmol . 1(-1). At the repeated samplings of the same animals, considerable variability of hormone levels was observed, which suggested a possibility of the pulsation character of the changes in the androgen also in this biological material. The correlation coefficients between the testosterone levels in semen plasma and ejaculate volume, as well as between the sperm concentration were positive, however, statistically insignificant. The relation between testosterone and the weight of testes was at the significance limit.

Animals↗
PubMed1982

[Concentration of plasma testosterone in adult roosters of a low-weight strain].

The levels of blood-plasma testosterone were studied in the adult light bodied strain cocks. Blood was sampled (1 ml) from the wing vein by means of a heparinized syringe six times within a 24-hour interval. The plasma obtained by centrifugation was kept in a refrigerator at a temperature of --18 degrees C. Testosterone was determined by the radioimmunological method. The testosterone levels were significantly higher (P less than 0.001), 18.8 nmol/l on the average, in the blood samples taken during the dark period of the day (10 o'clock p.m., 2 and 6 o'clock a.m.) than in the samples taken in the light part of the day (8 and 10 o'clock a.m., 2 o'clock p.m.) when the average concentration of the studied hormone was 10.7 nmol/l of plasma. the lowest levels of testosterone were recorded in the morning and the highest values were recorded late in the evening (10 o'clock p.m.). The differences in the levels of the hormone between sampling terms indicate that the testosterone level in adult animals shows diurnal variances. It was found by the study of the concentration of testosterone in the blood plasma of the same individuals within short intervals of time (30-60 min) that testosterone secretion in adult cocks had a pulsatory manner. The evaluation of hormone levels should include not only the diurnal variances but also the pulsatory manner of testosterone secretion.

Animals↗
PubMed1981

[Increased hepatic aryl 4-monoxygenase in chickens caused by lipophilic xenobiotics].

Hens were treated with three types of lipophil xenobiotics - polychlorinated biphenyl (PCB), lindane and hexachlorobenzene (HCB) - to study changes in the levels of microsomal proteins and in the activity of microsomal aryl 4-monooxygenase in liver. The above foreign substances were given in feed at a dose of 50 mg per kg during a fortnight. The level of microsomal proteins in liver increased after seven-day administration of xenobiotics and was always higher in the course of the experiment than in the controls. The activity of the microsomal enzyme (aryl 4-monooxygenase) was significantly higher in treated hens after seven- and 14-day interval, and also seven days after the end of feeding the contaminated feed mixture. Inductive properties were strongest in polychlorinated biphenyl (Delor 103), but lindane and hexachlorobenzene also induced a statistically significant rise, in comparison with the controls. It is shown that the inductive ability of lipophil xenobiotics is stronger in hens than in chicks, which may influence the metabolism of some biologically important substances in poultry organism.

Animals↗
PubMed1978

[Induction of hepatic microsomal enzymes in chickens effected by various persistent foreign materials].

Changes in the levels of microsomal proteins, in the activity of microsomal aniline hydroxylase, and in the effectivity of Thiopental were studied in chickens given the Czechoslovak-produced type of polychlorinated biphenyls - Delor 103. The increased activity of aniline hydroxylase and the decrease of Thiopental sleeping time in chickens exposed to the action of Delor 103 indicate that this preparation is able to induce liver microsomal enzymes in doses as low as 5 mg per kg of feed. The induction of liver microsomal enzymes appears to be an important factor, able to exercise a direct influence on the biotransformation of various biologically important substances in the organism of chickens.

Aniline Hydroxylase↗