The effect of calcium and magnesium supplementation on performance and bone strength of broiler chickens

Aim of the experiment was evaluation of the effect of reduced calcium and magnesium content in the broiler chickens diet on its parameters of fattening, bone strength and calcium and magnesium content in liver. The trial was performed with cockerels of Ross 308 hybrid (n = 160) which were fattened in cage batteries from day 11th to 36th day of age. Cockerels were divided into 4 groups (differ in various intake levels of calcium and magnesium) in four replications. The maize-wheat-soybean basal diet contained 2.33 g Ca and 1.58 g Mg per kilogram. Calcium was added by CaCO3 and magnesium by MgSO4. Control group (C) received feed mixture with added CaCO3 in dose of 19.49 g.kg-1 and 0.41 g.kg-1 of MgSO4. Three experimental groups contain added CaCO3 in dose of 11.83 g.kg-1 and 0 g.kg-1 MgSO4 (group Exp1); CaCO3 11.83 g.kg-1 and 0.41 g.kg-1 MgSO4 (group Exp2); CaCO3 19.49 g.kg-1 and 0 g.kg-1 MgSO4 (group Exp3), respectively. The feed consumption was daily monitored and the cockerels were weighed twice a week. At the end of the study the experimental animals were weighted and slaughtered by decapitation. The weight of carcasses, liver and proportion of breast and thigh muscle was determined in the selected chickens (n = 24). The atomic absorption spectrometry was used for Ca and Mg evaluation in liver tissues. Bone strength parameter was measured at the femur bone. The statistically significant differences (p >0.05) were not detected between control and experimental groups in the case of studied parameters of fattening, bone strength and calcium and magnesium content in the chicken's liver. Based on the obtained results it could be concluded the reduction of determined elements in the chicken diet did not deteriorate parameters of yield, elements content in liver tissue as well as the bone strength of broiler chickens.O

The effect of feeding milk thistle seed cakes on quality indicators of broiler chickens meat

This study was conducted to evaluate the effect of feeding milk thistle (Silybum marianum L.) seed cakes at dose 5% and 15% in feed mixture on quality indicators of broiler chickens meat. The used milk thistle seed cakes contained 3.73% of flavonolignans and 129.83 mg.kg-1 of cyanidin-3-glucoside. A 150 cockerels of Ross 308 were divided into three equal groups. The chickens were fattened on conventional deep litter system. The experimental groups received feed mixtures containing 5% of milk thistle seed cakes (MT5), 15% of milk thistle seed cakes (MT15) and third group was control - without milk thistle seed cakes (C). The trial lasted 37 days. At the end of trial was observed significant higher average weight of chickens (2,320.31 g) in control group. Compare to that the experimental group MT5 achieved significant lower mean bodyweight 2,166.69 g. From the perspective of fattening was decreased growth of chickens where a higher percentage of milk thistle seed cakes (MT15). The group MT15 was up to 420 g lower slaughter weight compared to the control group. This was probably due to the higher content of fiber in the feed. At the end of experiment 15 birds were selected randomly from each group, weighed and slaughtered. Feathers were removed and chickens were eviscerated. Carcass yield was calculated for each group like as percentage of live weight. The MT5 and MT15 group had significantly higher breast meat tenderness that the control group. Initial pH1 was highest in group with its middle addition of milk thistle seed cakes (MT5). Significant differences were not observed between control and group MT15. Breast meat was rated as the best in parameter flavour in control and MT15 group. The thigh meat was evaluated significantly best for colour parameter in MT15 group. Fibreness was rated as the finest in MT15 group. The addition of milk thistle seed cakes do not worsened sensory characteristic of breast or thigh meat of broilers and reflects optimal sensory quality traits

The effect of feeding wheat varieties with different grain pigmentation on growth performance, texture, colour and meat sensory traits of broiler chickens

The feeding effect of of three spring wheat genotypes (Vánek, Konini and UC66049) with different grain colour on growth performance, body composition and meat quality parameters of broiler chickens was tested. Ninety chickens were divided into three groups (control, Konini and UC) with 30 chickens in each. The tested genotypes were compares with standard variety Vánek (control) with common (red) grain colour. The two experimental groups received feed mixtures containing 38.2% of wheats with different grain colour: groups Konini (n = 30) and UC (n = 30) with. The third group (n = 30) had 38.2% of common wheat Vánek cultivar (Control group). The live weight of chickens between the experimental groups and control group was not significant different, as well as body composition and chemical analysis of breast and thigh meat of chickens. The feeding of wheat with different grain colour had no effect on performance parameters of broiler chickens. Breast meat tenderness according to the Razor Blade Shear Force was higher in control group against experimental groups. The colour change was not significantly different in all coordinates. pH values (measured after 1-hour post mortem) were found significantly higher in the group fattening with Konini wheat than control and UC groups. Chickens meat from the experimental group was characterised by steady overall quality. The effect of various feeding had no effect on meat quality in terms of relevance to consumers

The effect of hempseed expellers on selected quality indicators of broiler chicken's meat

The aim of the study was to evaluate the effect of feeding hempseed expellers in a feed mixture on the quality indicators of broiler chicken's meat. One hundred and fifty Ross 308 hybrid cockerels were used in the present study. The control group (HS0) was fed without hempseed expellers; the other two groups received diets containing 50 g.kg-1 and 150 g.kg-1 of hempseed expellers (HS5 and HS15, respectively). The birds were slaughtered at the age of 37 days, and samples of breast and thigh muscles were collected for determination of proximate chemical composition and technological properties, and sensory analyses. Feeding with hempseed expellers influenced the colour of meat with a significant difference observed for a* (redness) and b* (yellowness) values in the HS15 group. The colour of breast meat in HS15 group is more intense compared to HS5 and HS0 groups. Breast meat was evaluated as the best in terms of odour for HS15 group compared to HS0. The colour of thigh meat was better rated in the HSE supplemented groups compared to the controls. In conclusion, dietary supplementation with hempseed expellers appears to affect the colour and odour of broiler chicken's meat which is positive for the consumers. Including hempseed cakes can be recommended as a component of broiler chicken's feed.O

The distribution of selected toxic elements during the waste incineration

Import 29/09/2010Tato diplomová práce je zaměřena na distribuci toxických prvků, které se uvolňují při spalování odpadů. První polovina této práce se pohybuje v teoretické rovině a je rozdělena do třech částí. První část se soustředí na obecný popis spaloven, samotný spalovací proces a rovněž na platnou legislativu v oblasti spalování odpadů. V druhé části je poukazováno na tvorbu, toxicitu, charakteristiku a původ jednotlivých toxických prvků. Třetí část je zaměřena na obecné poznatky chování rizikových kovů při spalování odpadů podle některých studií. Druhá polovina diplomové práce je věnována samotné praktické části, jejíž součástí je odběr, úprava a analýza vzorků, dále vyhodnocení a diskuse analýz a výsledků.The diploma thesis specializes in distribution of hazardous metals, which are being released during the waste combustion. The first half of this thesis is concentrated on theoretical knowledge and is divided into three parts. The first part is focused on a general description of incinerators, a combustion process itself and also on an actual legislation in the field of waste combustion. The second part is adverted to production, toxicity, characteristics and origin of each hazardous element. The third part focuses on general knowledge of hazardous metal’s behaviour during the waste combustion according to some studies. The second half of this diploma thesis is devoted to practical part itself, in which is discussed collection and modification of specimens, then interpretation and discussion of analysis and results.Prezenční546 - Institut environmentálního inženýrstvívýborn

Analysis of metabolites produced by yeast colonies and biofilms

Some time ago it was shown (proved, described) that bacteria can communicate and regulate a gene expression by using small molecules. This phenomenon is called quorum sensing. The same phenomenon has been recently described in yeast. In yeast there are still many questions about the mechanism of sensing via small molecules. Few works and publications have described the impact of some small molecules, such as phenylethylalcohol or tryptophol, on morphology on Saccharomyces cerevisiae cell. The knowledge about the impact of the small molecules on the yeast multicellular community, like colonies, is still very limited these days. The aims of this work are analysis of exometabolites produced by colonies of different yeast strains cultivated on various solid complex media, by an untarged metabolomic approach. In accordance with the result of the exometabolites analyses we are going to test the impact of the selected substance on Saccharomyces cerevisiae colony morphology. The third part of this work is about the construction of Saccharomyces cerevisiae strains with deletion or lowering the expression of genes which encode proteins that are important in decarboxylation step of the Ehrlich pathway. Key word: Saccharomyces cerevisiae, microcolonies, tryptophol, isoamyl alcohol, isovaleric acid, colony..

The distribution of hazardous metals during the waste incineration process

Import 08/10/2008Prezenční546 - Institut environmentálního inženýrstvíNeuveden