Petr Sláma

Investigation into the Effect of Molds in Grasses on Their Content of Low Molecular Mass Thiols

The aim of this study was to investigate the effect of molds on levels of low molecular mass thiols in grasses. For this purpose, the three grass species Lolium perenne, Festulolium pabulare and Festulolium braunii were cultivated and sampled during four months, from June to September. The same species were also grown under controlled conditions. High-performance liquid chromatography with electrochemical detection was used for quantification of cysteine, reduced (GSH) and oxidized (GSSG) glutathione, and phytochelatins (PC2, PC3, PC4 and PC5). Data were statistically processed and analyzed. Thiols were present in all examined grass species. The effect of fungicide treatments applied under field conditions on the content of the evaluated thiols was shown to be insignificant. Species influenced (p < 0.05) PC3 and GSSG content. F. pabulare, an intergeneric hybrid of drought- and fungi-resistant Festuca arundinacea, was comparable in PC3 content with L. perenne and F. braunii under field conditions. Under controlled conditions, however, F. pabulare had higher (p < 0.05) PC3 content than did L. perenne and F. braunii. Under field conditions, differences between the evaluated species were recorded only in GSSG content, but only sampling in June was significant. F. pabulare had higher (p < 0.05) GSSG content in June than did L. perenne and F. braunii.

16. Effect of Diet Supplemented with Antioxidants (Selenium, Copper, Vitamins E and C) on Antioxidant Status and Ejaculate Quality of Breeding Boars

Abstract The aim of the experiment was to determine the effect of selected antioxidants (selenium, copper, vitamins E and C) on the antioxidant status of breeding boar ejaculate and ejaculate quality. In the first control group of boars (n = 10), the amount of antioxidants was not increased in feed. The second experimental group (n = 10) received the addition of selenium (0.5 mg/kg of diet), copper (10 mg/kg of diet), vitamin C (350 mg/kg of diet) and vitamin E (70 mg/kg of diet) in feed. The experiment lasted for 90 days. The addition of antioxidants increased GPx (by 28%), selenium content (by 49%; P<0.05), SOD (by 9%; P<0.05) and level of copper (by 63%; P<0.05) in the experimental group of boars. In the control group, the decrease of sperm motility (by 22%; P<0.05) was found at the end of the experiment. Other measured parameters such as ABTS antioxidant capacity, levels of MDA, metallothionein, zinc, ejaculate volume, concentration, total count of sperm and percentage of abnormal sperm cells were not significantly affected. The above mentioned results show that the addition of antioxidants does not increase the ejaculate quality but their lack can damage the quality indicators of boar ejaculate.

Effect of mercury on porcine ovarian granulosa cells in vitro

The objective of this in vitro study was to examine dose–dependent changes in the secretion activity [progesterone (P4) and insulin-like growth factor–I (IGF–I)] of porcine ovarian granulosa cells after experimental mercury (Hg) administration, including its apoptotic potential so as to ascertain the possible involvement of Hg in steroidogenesis. Ovarian granulosa cells were incubated with mercuric chloride [mercury (II) chloride or HgCl2] at the doses 50–250 μg mL−1 for 18 h and compared with control group without Hg addition. Release of P4 and IGF–I by ovarian granulosa cells was assessed by RIA and apoptosis by TUNEL assay. Observations show that P4 release by granulosa cells was significantly (P < 0.05) inhibited at all the doses, while IGF-I release was not affected at any of the doses used, although a decreasing trend in the release of IGF–I was noted in comparison to control. An increasing trend of apoptosis of granulosa cells was noted, the difference being significant (P < 0.05) only at the dose 130 μg mL−1 HgCl2, in comparison to control. Obtained data suggest a direct effect of Hg on the release of steroid hormone progesterone but not growth factor IGF-I, and a dose-dependent effect on apoptosis of porcine ovarian granulosa cells. Results indicate the interference of Hg in the pathways of steroidogenesis and apoptosis of porcine ovarian granulosa cells.

Characteristics of mammary secretions from Holstein cows at approximately 10 days before parturition: with or without intramammary infection*

ABSTRACT To evaluate the relationship between intramammary infection and basic characteristics of mammary secretion at late dry period, regarding mammary secretions, macroscopic observations, infection status, somatic cell counts (SCC), serum albumin concentrations, immunoglobulin (Ig) G1, and IgG2 levels were examined on 20 dairy cows at 9–12 days before calving. Intramammary infections were found in mammary secretions from 37 of the total 80 quarters. All of the mammary secretions with intramammary infection showed lower viscosity than that of normal colostrum. In four mammary secretions without intramammary infection, some macroscopic abnormalities were found. For mammary secretions without intramammary infection or macroscopic abnormality, viscosities were apparently higher than that in normal colostrum, indicating that viscosity is associated with macroscopic normality of the mammary secretion at approximately 10 days before calving. SCC and serum albumin concentrations were significantly higher in mammary secretions with intramammary infection or macroscopic abnormality. The SCC and serum albumin concentrations were correlated with viscosity of the mammary secretions, suggesting that most intramammary infections at approximately 10 days before calving may cause mastitis with increased permeability of the blood–milk barrier. No significant difference was observed in concentrations of IgG1 and IgG2, regardless of the presence of intramammary infections or macroscopic abnormalities.

Jatropha seed cake and organic waste compost: the potential for improvement of soil fertility

Abstract Modern agriculture faces to new challenges and problems. Application of organic waste compost (Cp) and Jatropha seed cake (JSC) represents new possibilities to improve soil organic matter (SOM) and thus reduce the risk of soil degradation. Our paper presents results of laboratory experiment. Based on these results, we conclude that the application of organic substances has positive effect on soil fertility but the impact of individual substances is different. JSC has higher influence on soil properties (microbial activity and plant production) in the short term. Conversely, Cp affects soil properties in the long term. These properties are due to their chemical composition.

Evaluation of milk yield in tsigaiewes by somatic cell count

The objective of our research was to study daily milk production which was affected by somatic cell count (SCC). The study was performed on a selected flock of purebred Tsigai ewes (326 animals). Regular milk yield recording was performed during the evening milking in around the middle of April, May and June. Milk samples were analyzed for basic milk composition (fat, protein and lactose) and somatic cells count. SCC were evaluated using decadic l ogarithm (logSCC).According to animals, the dairy ewes were divided into the four groups on the basis of individual SCC (G 1 = SCC 600 × 10 3 cells.mL -1 to study the frequency of distribution of animals in selected group of ewes throughout experimental period. The average daily milk production in selected flock of Tsigai was 421.02 mL. We reached the highest daily milk production in April 476.40 ml and the highest content of fat and protein in June, while milk production was the lowest. From this flock of purebred Tsigai 76% of eweswere below SCC 300 × 10 3 cells.mL -1 . This SCC indicated a good health status of experimental ewes, at which 61% sheep were at the first lactation. We found a tendency to lower milk production by a higher SCC. With the increasing SCC decreased lactose content from 4.78% (G1) to 4.32% (G4). Reduced lactose content refers to the occurrence of mastitis and there is a need for performing bacteriological examination in milk.

Effect of Streptococcus uberis infections on cell population of bovine mammary gland

Streptococcal bacteria are one of the most important pathogens causing different type of bovine mastitis. In this respect, it is very important to study effect of streptococcal infections on cell populations of bovine mammary gland to improve knowledge how to prevent and treat streptococcal infections of bovine mammary gland. Streptococcal bacteria can affect different cell processes, for example, programmed cell death (apoptosis) and expression of some cell receptors on leukocytes such as neutrophils, lymphocytes and macrophages of mammary gland. This review summarizes information about effect of streptococcal infections on leukocytes of bovine mammary gland.