Engineering Design of Conveyor Belt Drive for the Coupling Boom Feed

Import 05/08/2014Předmětem této diplomové práce je konstrukční návrh pohonu pásového dopravníku spojovacího výložníku zakladače. V úvodní části diplomové práce jsem se zabýval dopravou na zakladačích a byl proveden dle zadaných parametrů základní výpočet pásového dopravníku na spojovacím mostě zakladače ZP 3500. Další část diplomové práce se zabývá konstrukč-ním návrhem poháněcí stanice dopravníku na spojovacím mostě a následně i konstrukčním návrhem převodové skříně pohonu. Závěrečná část se zabývá základním výpočtem převodové skříně. V příloze předkládám sestavný výkres poháněcí stanice a detailní výkres výstupní hřídele.The subject of this thesis is the design of the conveyor belt drive connecting the boom stackers. In the introductory part of the thesis I dealt with transportation to the foundation and was carried out aucording to set parameters of the basic calculation of the conveyor belt on the connecting bridge stackers ZP 3500. Another part of the thesis deals with the structural design of the conveyor drive unit to the connecting bridge and consequently the desing of the gearbol actuator. The final part deals with the basic calculation of the gearbox. In annex I present the plan of the drive unit and a detailed drawing of the output shaft.340 - Katedra výrobních strojů a konstruovánívelmi dobř

Influence of milk thistle pressed parts on rats liver histology

Milk thistle (Silybum marianum) is one of the best known and very often used herbs with positive effect on liver. The aim of this article was to study influence of addition of milk thistle pressed parts in feed ration on liver histology and weight increase of laboratory rats. The experiment was tested by 15 pieces of laboratory rats divided into 3 groups (A, B, C). The rats in first group (A) hade feed ration with addition of 10% milk thistle pressed parts, second group (B) hade feed ration with 20% and control group (C) hade feed ration without addition of milk thistle pressed parts. The silymarin content of pressed milk thistle seed was 26.2 mg/g. The aim of this article is to study influence of addition of milk thistle pressed parts in feed ration on liver histology and weight increase of laboratory rats. The hypothesis is that the feeding addition - milk thistle seed pressed parts has positive effect on weight performance and liver histology. Does the feeding addition have any effect on these health indicators? Does feeding of milk thistle seed pressed parts have any sense? In results, the groups with addition of milk thistle had significant bigger average gain increases than the control group. Histological results vary considerably among groups of rats. All rats in the control group had dystrophic liver with sinusoidal congestion. In most rats of the group A, the dystrophy was minimal without congestion. On the other hand, most of rats of the group B had liver dystrophy caused by large droplets steatosis with congestion. All rats in control group C were found to have significant dystrophy caused by steatosis. The results indicate rats receiving the addition of milk thistle pressed parts in their feed had a lower incidence of liver steatosis due to the hepatoprotective effects of silymarin.O

Influence of mycotoxins in barley monodiets on growth performance and rats liver histology

The presence of mycotoxins in animal feed cause health disorders and can also contribute to other factors such as stress, lack of nutrition, infectious agents etc. The aim of this article was to study effect of feed ration contaminated with mycotoxins on liver histology and live weight of laboratory rats. 15 pieces of laboratory rats were divided into 3 groups (A, B, C). The rats in first group (A) fed with part of 30% mycotoxin-contaminated barley, in second group (B were fed with 60% and in control group (C) were fed without mycotoxin-contaminated barley. Content of deoxynivalenol (DON) was 9634 µg/kg and content of zearalenone (ZEN) was 2192 µg/kg. Barley monodietus were given rats in all groups to induce a nutritional imbalance. The aim of this study was to monitor the effect of mycotoxins and nutritional imbalances on weight gains and liver histology. The question is, "will the presence of mycotoxins in feed dose increase negative effect of a monodiets on health status?" No significant differences were found between the observed parameters. The presence of mycotoxins did not aggravate the negative effect of the monodiets on liver histology of the experimental rats.O

The Influence of Calcium Intake During the Period of Sexual Maturation of Pullets on its Retention and Eggshell Quality of Laying Hens

The aim of the study was to determine the calcium requirements in preparation period of the sexual mature and egg-laying and evaluate development of calcium retention in the first laying period of the hybrid combination Bovans Brown hens. The experimental trial lasted from 14 to 30 weeks of hens age. The animals were fed ad libitum with a pelleted complete feed mixture with 42 g/kg of calcium content. The amount of calcium retained by pullets gradually increased along with feed intake depending on age and preparation for sexual maturity and was around 0.39 +- 0.19 g Ca in the first period. Ca retention increased up to an average of 0.85 g Ca from 8 day before laying the first egg. Retention dropped sharply on the day of laying the 1st egg and a negative Ca balance occurred. Shell output was 1.75 +- 0.21 g/day for the beginning of laying and subsequently increased to 2.23 +- 0.08 g/ day during evaluate peak laying. The range weight of the first laid eggs was 45 +- 5 g. Percentage of eggshell move around an average of 10 +- 0.37% throughout the observed period. The daily calcium intake of pullets was 3.56 +- 0.26 g/day. With the beginning of laying, the daily intake increased to an average of 4.51 +- 0.43 g/day Ca. Before reaching sexual maturity, the calcium apparent digestibility of laying hens was relatively low, averaging around 22%, but the moment the hens began to lay, the apparent calcium digestibility began to increase to an average of 50%. Feeding a non-standard feed mixture with a higher calcium content than usual in mixtures for pullets did not have a negative effect on the finishing of animal development, the onset of sexual maturity, or deterioration of the observed parameters of eggs quality.O

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

Study of antioxidant and antimicrobial properties of grapevine seeds, grape and rosehip pressing

In our experiment, we studied the antimicrobial and antioxidative effect of phytogenic additives. Three additives (grapevine seeds, grape and rosehip pressings) were selected to be monitored. The extracts about concentrations of 1:3 and 1:5 were prepared from them. The monitoring of antimicrobial properties was focused on the pathogenic bacteria Clostridium perfringens and Escherichia coli causing a serious disease in avian species. The bacteria were prepared in the dilutions of 102, 104 and 106. The antimicrobial effect was observed in the inhibition zones. The antioxidant activity was determined using DPPH method within the antioxidant analysis. Furthermore, the content of flavanols, hydroxycinnamic acids and the total content of polyphenolic compounds was also determined. In the monitoring of the antimicrobial effect of grapevine seeds, grape and rosehip pressings at E. coli, a reduced growth of KTJ (colony forming units) was observed in the disk area during the dilution of 106 and 104. Reduced growth of C. perfringens at a dilution of 106 was noticed using the extracts of grapevine seeds and grape pressings. Low reduced growth of C. perfringens at a dilution of 106 was found out using rosehip pressings. In a dilution of 102 and 104 in C. perfringens and 102 in E. Coli, a very low increase of KTJ was observed therefore the zones of inhibition were not possible to measure. In all monitored additives, the antimicrobial effect was proved. The additives reduced the growth of pathogenic E. coli and C. perfringens. Within the antioxidant analysis, the highest antioxidant activity was found out in grapevine seeds (7.021 g.L-1 GAE), which also contained the highest content of flavanols (3000 times higher than the rosehip pressings and 300 times higher than grapevine seeds pressings), hydroxycinnamic acids (1000 times higher than in grape pressings and 7600 times higher than in rosehip pressings) and the total content of polyphenolic compounds (580 times higher than grape pressings and 2000 times higher than the rosehip pressings) of the monitored additives

Factors Affecting the Content of Ergosterol and Zearalenone in Selected Grass Species at the End of the Growing Season

The objective of the study was to assess the safety of forage prepared from selected grass species by means of the analysis of ergosterol and zearalenone. Graminaceous plants studied at the end of their growing season were Festulolium, Dactylis glomerata and Arrhenatherum elatius. Other indicators assessed were the content of ergosterol and zearalenone during the autumn and the intensity of grassland use in the summer season as related to the studied contents of metabolites. Grasslands were harvested either in October, November or December. The secondary metabolites were analyzed by means of high performance liquid chromatography. At the end of the growing season, the ergosterol content was the lowest in the Festulolium forage (110.04 mg kg-1), the highest contents were observed in the Dactylis glomerata and Arrhenatherum elatius forages (145.73 mg kg-1 and 139.55 mg kg-1, respectively). The safety of Festulolium was also corroborated by the low zearalenone content (0.357 mg kg-1). On the other hand, the high ergosterol content in Arrhenatherum elatius was combined with a high content of zearalenone (1.554 mg kg-1). Although Dactylis glomerata exhibited an ergosterol content comparable with that of Arrhenatherum elatius forage, its zearalenone content was comparable to the Festulolium forage. Among the three species under study we found a significant difference (P P -1). The higher (P -1) was caused by the Arrhenatherum elatius forage. Moreover, the contents of ergosterol and zearalenone were affected (P < 0.01) also by the number of cuts in summer. The higher ergosterol content indicated a higher forage infestation by fungi and the inherent risk of the occurrence of mycotoxins. However, the high ergosterol content not always correlated with the high content of zearalenone. When cattle is grazing in winter, a higher occurrence of mycotoxins in the feed may be expected and the related damage to animal metabolism may increase the number of diseased animals with consequent impact on animal production, performance and health and animal husbandry economics

Uporaba voltmetrije za određivanje tiola i metalotioneina male molekularne mase u krvi svinje (Sus scrofa domestica)

Metallothioneins (MT) play a key role in maintaining the homeostasis of essential metals and in protecting of cells against metal toxicity as well as cell oxidative damaging. The aim of this work is to propose a new approach for processing a biological sample for analysis of thiols including metallothioneins. Moreover, the proposed procedure is tested on quantification of MT and total thiol content in blood serum of pig (Sus scrofa domestica), which has not been previously been performed. The blood serum (10 ml) was collected and transferred to 0.2 M phosphate buffer (990 ml). The sample (100 × diluted) was placed in a thermomixer, where heat denaturation of most of the proteins proceeded. The processed blood serum sample was electrochemically measured to determine total content of thiols (cysteine, glutathione, metallothionein and other low molecular thermostable thiols) and content of MT. The average level of the thiols and MT were estimated as 165 ± 20 mM and 5.2 ± 0.6 mM, respectively.Metalotioneini (MT) igraju ključnu ulogu u održavanju homeostaze esencijalnih metala i u zaštiti od toksičnih metala te od oštećivanja stanice oksidacijom. Cilj ovog rada je predložiti novi pristup obradi bioloških uzoraka za analizu tiola, uključujući metalotioneine. Osim toga, predloženi postupak se testira pri kvantifikaciji MT i ukupnog sadržaja tiola u krvnom serumu svinje (Sus scrofa domestica), što se dosad nije radilo. Prikupljan je krvni serum (10 ml) te prebacivan u 0.2 M fosfatni pufer (990 ml). Uzorak (100 × razrijeđen) je stavljen u termomikser gdje se nastavila toplinska denaturacija većine proteina. Obrađeni uzorak seruma je elektrokemijski izmjeren da bi se odredio ukupni sadržaj tiola (cistein, glutation, metalotionein i drugi termostabilni tioli male molekularne mase) te sadržaj MT. Prosječna razina tiola i MT su procijenjeni na 165 ± 20 mM, odnosno 5.2 ± 0.6 mM

Effect of chamomile supplements to feeding doses on antimicrobial parameters in poultry

Due to a ban of use of antibiotic growth promoters in the poultry industry it is necessary to look for alternative solutions. The use of some herbs showing antimicrobial effects can be one of such alternatives. In this experiment, effects of three different concentrations of chamomile (Matricaria chamomilla) extract, (0.3%; 0.6% and 1.2%) in feeding doses on the microbial population in the gastrointestinal tract of growing broiler chickens were studied. The main attention was paid to the population of Clostridium perfringens and to numbers of coliform microbes. Clostridia were cultivated under anaerobic conditions at 46 °C on the Tryptone Sulfite Neomycin (TSN) agar for a period of 24 hours. Coliform microbes were grown on the violet red bile lactose (VRBL) agar at 37 °C for a period of 24 hours. The experiment lasted 39 days and involved 80 chicks that were slaughtered in the course of their growth period at the age of 18, 25, 32 and 39 days; there were 5 chicks in each group. The obtained results indicated that increasing doses of chamomile in the feeding ration decreased numbers of coliform microbes in the digestive tract of chicks and also reduced the population of C. perfingens. © 2014 Potravinarstvo

Influence of garlic extract on antioxidant status of chicken

In 2006 the European Union banned the feeding of antibiotic growth promoters because of possible risk of drug resistance in human pathogens bacteria. This is the reason for the study of various phytogenic additives and their extracts as a natural source of biologically important compounds. Antimicrobial substances are a commonly included in chicken feed rations. They are used mainly as prevention against various diseases, and also to stimulate growth. The beneficial effects of garlic on animal organism resulting from their antimicrobial, antioxidative and antihypertensive properities. Studies focused on growth, conversion and meat quality of different types of animals indicate its positive effects. In our experiment we studied the influence of garlic extract in a dose of 0, 10 g and 15 g per 1 kg of chicken feed mixture. We focused on weight gains and antioxidant status of an organism. The experiment took 39 days. 54 seven-day-old chickens were included in the experiment. The chickens were weighed once a week, when aged 11, 17, 24, 31 and 38 days, at the same time of the day. The chickens had ad libitum access to feed ration and water. The chickens were taken blood sample at the end of the experiment when 39 days old. Their antioxidant status were measured using ABTS, FRAP and DPPH methods. Our results show that owing to higher concentration of garlic extract in feed ration the antioxidant status of observed chickens was increased. DPPH method showed an increase in antioxidant status of both experimental groups by 38% (a group with a dose of 10 g/kg of mixture) and by 46% (a group with a dose of 15 g/kg of mixture) compared to the control group. When using FRAP method, antioxidant status of both G10 and G15 groups increased by 24%, resp. 16%. No evidential differences in antioxidant activity between the experimental groups and control group were found using ABTS method. The supplement of garlic extract into a feed ration did not have any influence on weight gains of chickens. © 2014 Potravinarstvo