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Methionine is one of the most frequently supplemented amino acids in raising of poultry. However, an overdose of methionine can cause hyperhomocysteinemia. Folic acid, taking part in the process of homocysteine remethylation, is a factor affecting the reduction of the concentration of this amino acid. The study was carried out in 2 stages. The experiment of step I was to investigate the effect of methionine and/or folic acid administration in ovo in the early stage of embryogenesis (E4), and the experiment of the second stage - in the late stage of embryogenesis (E17) on the following biochemical parameters of chicken blood: glucose concentration in whole blood and concentration of homocysteine and uric acid in plasma of domestic chickens (Gallus gallus domesticus). Our results confirm that methionine supplementation may increase the concentration of uric acid and homocysteine. Moreover, we demonstrated that folic acid administered during embryogenesis decreased homocysteine concentration, also in groups simultaneously supplemented with methionine, especially in the initial stage of postnatal life of the bird.
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Galinhas , Ácido Fólico , Homocisteína , Metionina , Animais , Metionina/administração & dosagem , Metionina/farmacologia , Ácido Fólico/administração & dosagem , Ácido Fólico/farmacologia , Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Homocisteína/sangue , Embrião de Galinha/efeitos dos fármacos , Suplementos Nutricionais/análise , Ácido Úrico/sangue , Glicemia/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacosRESUMO
We study the dimer model on subgraphs of the square lattice in which vertices on a prescribed part of the boundary (the free boundary) are possibly unmatched. Each such unmatched vertex is called a monomer and contributes a fixed multiplicative weight z>0 to the total weight of the configuration. A bijection described by Giuliani et al. (J Stat Phys 163(2):211-238, 2016) relates this model to a standard dimer model but on a non-bipartite graph. The Kasteleyn matrix of this dimer model describes a walk with transition weights that are negative along the free boundary. Yet under certain assumptions, which are in particular satisfied in the infinite volume limit in the upper half-plane, we prove an effective, true random walk representation for the inverse Kasteleyn matrix. In this case we further show that, independently of the value of z>0, the scaling limit of the centered height function is the Gaussian free field with Neumann (or free) boundary conditions. It is the first example of a discrete model where such boundary conditions arise in the continuum scaling limit.
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Diatomite has recently been the subject of intensive scientific research aimed at its extensive use in industry, breeding and agriculture. The only active diatomite mine is in Jawornik Ruski, in the Podkarpacie region of Poland. Chemical pollution in the environment, including that from heavy metals, poses a threat to living organisms. Reducing the mobility of heavy metals in the environment through the use of diatomite (DT) has recently gained much interest. More effective immobilisation of heavy metals in the environment with DT, mainly through the modification of its physical and chemical properties by various methods, should be applied. The aim of this research was to develop a simple and inexpensive material showing more favourable chemical and physical properties compared with unenriched DT in terms of metal immobilisation. Diatomite (DT), after calcination, was used in the study, considering three grain fractions, i.e., 0-1 mm (DT1); 0-0.5 mm (DT2) and 5-100 µm (DT3). Biochar (BC), dolomite (DL) and bentonite (BN) were used as additives. The proportion of DTs in the mixtures amounted to 75%, and of the additive, 25%. The use of unenriched DTs after calcination poses the risk of releasing heavy metals into the environment. Enrichment of the DTs with BC and DL resulted in a reduction or absence of Cd, Zn, Pb and Ni in aqueous extracts. It was found that for the specific surface area values obtained, the additive used for the DTs was of crucial importance. The reduction in DT toxicity has been proven under the influence of various additives. The mixtures of the DTs with DL and BN had the least toxicity. The obtained results have economic importance, as the production of the best quality sorbents from locally available raw materials reduces transport costs and thus the environmental impact. In addition, the production of highly efficient sorbents reduces the consumption of critical raw materials. It is estimated that the savings from producing sorbents with the parameters described in the article can be significant in comparison with popular competitive materials of other origins.
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Even though chinchillas have been farmed for a century, there are not many studies concerning their behaviour in captivity or their optimal housing conditions, both of which are important factors in the assessment of their welfare. This study aimed to evaluate the effect of different cage types on chinchillas' behaviour and their reactions towards humans. Female chinchillas (n = 12) were kept in three types of cages: standard with a wire floor (S); standard with a deep litter floor of shavings (SR); and enlarged with a deep litter floor of shavings (LR). Animals spent 11 weeks in each type of cage. The chinchillas' reactions toward humans were observed via intruder test. Ethograms were prepared based on round-the-clock video recordings. The activity of the chinchillas was compared, taking into account the different cage types and the animals' varying responses to the hand test. The generalized ordered logistic regression model was used to ascertain whether cage type has an effect on a chinchilla's behaviour towards humans. To compare the time distribution of various activity between chinchillas, the non-parametric Scheirer-Ray-Hare test was used. Animals kept in LR cages presented significantly less timid reactions in comparison to those kept in S and SR cages. The chinchillas spent most of their time resting (68% of the day), in locomotion (23%), and eating or drinking (8%); they spent only 1% on grooming behaviour. Cage enrichment generally reduced the fear of humans. However, the average chinchilla response to the hand test was classified in each type of cage as "cautious". Analyses of the ethograms indicated that the chinchillas were active mostly during the dark stage of the day. In conclusion, the larger cage size and its enrichment (particularly litter) reduced the fearfulness and passivity of the animals, which could be evidence of better welfare conditions.
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Comportamento Animal , Locomoção , Animais , Humanos , Feminino , Chinchila , Comportamento Animal/fisiologia , Gravação em Vídeo , MedoRESUMO
The addition of functionalized materials (biochar, zeolite, and diatomite) and lyophilized metabolic products of Pseudomonas sp. and Bacillus subtilis to composted biomass may bring many technological and environmental benefits. In this study, we verify the effects of biochar, zeolite Na-P1 (Na6Si10Al6O32·12 H2O), diatomite (SiO2_nH2O), and bacterial metabolites on the composting of biomass prepared from poultry litter, corn straw, grass, leonardite, and brown coal. The experimental design included the following treatments: C-biomass without the addition of functionalized materials and bacterial metabolites, CB-biomass with the addition of biochar, CBM-biomass with the addition of biochar and bacterial metabolites, CZ-biomass with the addition of zeolite, CZM-biomass with the addition of zeolite and bacterial metabolites, CD-biomass with the addition of diatomite, and CDM-biomass with the addition of diatomite and bacterial metabolites. Composts were analyzed for enzymatic and respiratory activities, mobility of heavy metals, and the presence of parasites. The results of this study revealed that, among the analyzed functionalized materials, the addition of diatomite to the composted biomass (CD and CDM) resulted in the most effective immobilization of Cd, Zn, Pb, and Cu. Zinc immobilization factors (IFHM) for diatomite-amended composts averaged 30%. For copper, each functionalized material was found to enhance mobilization of the element in bioavailable forms; similar observations were made for lead, except for the compost to which biochar and bacterial metabolites were added (CBM). The determined values of biochemical indicators proved the different effects of the applied functionalized materials and bacterial metabolites on the microbial communities colonizing individual composts. The dehydrogenase activity (DhA) was lower in all combinations as compared with the control, indicating an intensification of the rate of processes in the studied composts. The highest basal respiration (BR) and substrate-induced respiration (SIR) activities were determined in composts with the addition of bacterial metabolites (CBM, CZM, and CDM). The addition of functionalized materials completely inactivated Eimeria sp. in all combinations. In the case of Capillaria sp., complete inactivation was recorded for the combination with zeolite as well as biochar and diatomite without bacterial metabolites (CB, CZ, and CD).
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Halloysite, a clay mineral of the kaolin, has specific properties, characteristic for the conditions in which it was formed. The aim of the study was to determine the effect of halloysite from the Dunino deposit in a complete diet for pigs on daily body weight gain (BWG), feed conversion ratio (FCR), blood parameters, chemical composition of meat and chosen environment indices in the piggery. The trial was conducted on 144 piglets from weaning (d 29) to 85th day of life, then on 40 porkers divided into two groups. Animals were fed diets without (group C) or with halloysite (group E; 1.5% until d 128, then 1.0%). Pigs from group E were characterized by a lower number of days with diarrhea. The average BWG in E group was 44 g higher than in group C (P < 0.01). In turn, during the fattening period, the difference in BWG between groups was 60 g in favor of E (P < 0.05) and average FCR in group E was 4.9% lower compared to group C (P < 0.05). At the end of the study, the pigs from group E had 6.9% higher final body weight (P < 0.01). During both the morning and evening measurements, ammonia concentration in the air was lower by 16.3% and 23.8%, respectively. The use of halloysite enabled improvement of pig fattening efficiency, while reducing the costs of pork production and the negative effect of ammonia on the animals' welfare and environment.
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Amônia , Carne , Animais , Argila , Suplementos Nutricionais , Suínos , Translocação Genética , Aumento de PesoRESUMO
The current global crisis facing the world is the COVID-19 pandemic. Infection from the SARS-CoV-2 virus leads to serious health complications and even death. As it turns out, COVID-19 not only physically assails the health of those infected, but also leads to serious mental illness regardless of the presence of the disease. Social isolation, fear, concern for oneself and one's loved ones, all of this occurs when a pandemic overloads people. People exhibit numerous neurological disorders that have never happened to them before. Patients are diagnosed with frequent panic attacks, the result of which can be seen in their Quantitative Electroencephalogram results. This test may be one of the main diagnostic tools of the COVID-19 pandemic. From the results obtained, it is possible to compare and draw conclusions. This method of testing effectively allows EEG biofeedback training and observes its effect on brain activity. The feedback received in this way gives us the opportunity to properly tailor a protocol for the patient and their conditions. Numerous studies support the effectiveness of EEG biofeedback for panic attacks and other psychiatric disorders. The purpose of our study was to show the effectiveness of EEG biofeedback with a Quantitative Electroencephalogram of the brainwave pattern after having COVID-19 and what symptoms may result.
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Ondas Encefálicas , COVID-19 , Neurorretroalimentação , Transtorno de Pânico , COVID-19/terapia , Eletroencefalografia/métodos , Humanos , Pandemias , Transtorno de Pânico/terapia , SARS-CoV-2RESUMO
The aim of this work was to develop a new coating material based on Ni20Cr alloy modified with up to 50%wt. rhenium. The modification was carried out by the mechanical mixing of the base powder and ammonium perrhenate with the subsequent thermoreduction in an H2 atmosphere. The obtained powder consists of a nickel-chromium core surrounded by a rhenium shell. The characterization of the powders-including their microstructure, phase and chemical composition, density, flowability, particle size distribution, and specific surface area-was performed. The influence of plasma current intensity and hydrogen gas flow on in-flight particle temperature and velocity were investigated. The results indicate that there is interdiffusion between the base Ni20Cr and the rhenium shell, resulting in intermediary solid solution(s). The modified powders have a higher specific surface area and a lower flowability, but this does not prevent them from being used as feedstock in plasma spraying. In-flight measurements reveal that increasing the content of rhenium allows for the higher temperature of particles, though it also reduces their speed.
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The aim of the current study was to assess the influence of embryonic exposure to cadmium on basic and derived erythrocyte indices, the morphology and morphometric properties of erythrocytes, as well as erythrocyte spectrin distribution in newly hatched Gallus gallus domesticus chicks. The eggs were injected with cadmium (Cd) at a dose of 2 µg, 4 µg, 6 µg, or 8 µg per egg on the sixth day of incubation. Blood samples were collected on the first day after hatching. Exposure to cadmium resulted in higher levels of red blood cell count, hemoglobin concentration, and hematocrit value, while derived erythrocyte indices were lower (mean corpuscular volume) or higher (mean corpuscular hemoglobin concentration) in comparison to the control. These changes occurred in animals exposed to higher doses of this toxic agent. In cadmium-treated individuals (2 and 8 µg of Cd), the percentage of erythrocytes which exhibited changed shape increased. Increases in the length (6 and 8 µg) and width (2, 6, and 8 µg) of erythrocytes and the length and width of the nucleus (2-8 µg) of red blood cells were observed. Changes in spectrin distribution were also observed, which indicate alterations at structural and molecular levels.
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Galinhas , Índices de Eritrócitos , Animais , Cádmio/toxicidade , Índices de Eritrócitos/veterinária , Eritrócitos , Óvulo , Espectrina/farmacologiaRESUMO
Our research aimed to show acrylamide's influence on inflammatory processes, the oxidative stress it causes in the cholinergic system, and the possibility of reducing inflammation via supplementation with α-tocopherol. For this purpose, an in ovo model was used where the embryos were exposed to acrylamide, α-tocopherol and a cocktail of these substances. After 48 h of exposure, we collected brain samples and performed biochemical assays to examine the effect of the chosen substances on oxidative stress (malondialdehyde-MDA and reduced glutathione-GSH) and acetylcholinesterase activity (AChE). The results showed that acrylamide decreased AChE activity in the examined brain samples by about 25% in comparison to the control group, and this effect was decreased by administering α-tocopherol. The concentration of malondialdehyde significantly increased in the group given acrylamide, while, in the group with α-tocopherol, the observed concentration was lower in comparison to the control group. Moreover, a decrease in glutathione concentration was observed after the administration of acrylamide; however, the protective effect of α-tocopherol was only slightly visible in this case. In conclusion, α-tocopherol minimizes the harmful effects of acrylamide on AchE, and it can minimize the concentration of MDA.
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Acrilamida/toxicidade , Encéfalo/efeitos dos fármacos , Ovos/análise , Inflamação/tratamento farmacológico , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , alfa-Tocoferol/farmacologia , Animais , Antioxidantes/farmacologia , Encéfalo/patologia , Embrião de Galinha , Galinhas , Inflamação/induzido quimicamente , Malondialdeído/metabolismoRESUMO
Spent coffee grounds (SCG) as well as chicken (CES) or duck eggshells (DES) left over from the artificial hatching technology are proposed as potential soil improver and/or organic-mineral fertiliser components. Therefore, it seems interesting and necessary to evaluate the chemical composition of these wastes and their mixtures in terms of their possible use for that purpose. The study was conducted under the incubation experiment conditions using a mixture of SCG and eggshells (10:1 ratio). Macronutrients, i.e. C, N, S, were determined by the catalytic combustion method, while P, K, Mg, Ca, Na by atomic spectrometry. It was found that SCG were rich in C, N, P, and K, while eggshells in Ca, Mg, Na, and S. However, CES compared to DES were richer in deacidifying components (i.e. Ca, Mg, K). At the same time, the content of macronutrients in eggshells decreased gradually along with the embryo development. For this reason, the mixture of SCG and shells of unembryonated chicken eggs (CES I) had the best chemical and usable proprieties. To conclude, the chemical properties of the mixtures of spent coffee grounds and eggshells indicate their possible application in soil bioengineering.
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The aim of the study was to determine the effect of supplementing broiler chickens' diets with halloysite on daily body weight gain (BWG), feed conversion ratio (FCR), daily water consumption (DWC), and some broiler house hygiene parameters. The trial was conducted on 18,000 broiler chickens divided into two groups throughout the 42-day (D) rearing period. The birds were fed complete diets without (group C) or with halloysite addition (1%, group E) from D8 of rearing. No difference in the mortality rate was observed between groups C and E. Birds from group E had a tendency (0.05 < p < 0.10) towards a higher body weight at D32 and D42, a higher BWG, and a lower FCR compared to group C during the entire rearing period. Average DWC differed only in the finisher period, with a tendency towards lower overall DWC in group E. The concentration of ammonia in the air from D21 to D35 was increased more than 5-fold in group C but only 1.5-fold in group E. In conclusion, the use of halloysite as a feed additive in the diet of broiler chickens resulted in a reduction in feed consumption per unit of BWG and higher utilisation of crude protein, which led to improved environmental conditions.
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The article presents the influence of mechanical alloying and plastic consolidation on the resistance to arc erosion of the composite Ag-Re material against the selected contact materials. The following composites were selected for the tests: Ag90Re10, Ag95Re5, Ag99Re1 (bulk chemical composition). Ag-Re materials were made using two methods. In the first, the materials were obtained by mixing powders, pressing, sintering, extrusion, drawing, and die forging, whereas, in the second, the process of mechanical alloying was additionally used. The widely available Ag(SnO2)10 and AgNi10 contact materials were used as reference materials. The reference AgNi10 material was made by powder metallurgy in the process of mixing, pressing, sintering, extrusion, drawing, and die forging, while the Ag(SnO2)10 composite was obtained by spraying AgSniBi alloy with water, and then the powder was pressed, oxidized internally, sintered, extruded into wire, and drawn and die forged. The tests of electric arc resistance were carried out for loads with direct current (DC) and alternating current (AC). For alternating current (I = 60 A, U = 230 V), 15,000 switching cycles were made, while, for constant current 50,000 (I = 10 A, U = 550 V). A positive effect of the mechanical alloying process and the addition of a small amount of rhenium (1% by mass) on the spark erosion properties of the Ag-Re contact material was found. When DC current of 10 A was used, AgRe1 composite was found to be more resistant than commonly used contact materials (AgNi10 and Ag(SnO2)10).
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Staphylococcus aureus bacteria are components of physiological biocenosis of skin or mucous membranes in some animals' genera but also they are dangerous opportunistic pathogens responsible for infections of various localization, course or manifestations. Proteins produced by these bacteria destroy tissues, leukocytes and cause haemolysis of erythrocytes. Host organisms respond by defence mechanisms. Production of heat stress proteins (HSPs) is one of defence responses of infected host organism. To evaluate infection and host defence mechanisms some animal models of experimental infection are reported. Use of chick embryo model allows demonstrating adequate differences in staphylococcal virulence depending on the strain genotype. The aim of the study was to examine the changes in heat shock protein HSP70 levels in chick embryo tissues after infection caused by S. aureus strains no. tu2, pa3, ch5, ch10, ch24, and ch25 isolated from chickens. The bacteria were injected directly into fluid of amnion cavity and incubated for 10 days. The mortality of particular chick embryos was reported and the tissues for further analysis were taken every day from day 13 to day 19. The levels of heat stress protein HSP70 were determined by dot-blot method. Results showed that the strains no. ch5, ch24, and ch25 were the most virulent. HSP70 levels increased in all groups of injected embryos at the same time the hatching process was started. The presented study showed that the infected chick embryos were characterized by higher HSP level from 12.3% up to 19.7% compared to the control group. The morphological analysis showed numerous erythrocytes with damaged cell membranes and morphological changes of erythrocytes. Changes in the level of HSP70 protein can be a useful indicator of infection caused by S. aureus bacteria. Additionally, chicken embryo is a helpful research model in studies of pathogenesis of diseases caused by bacteria.
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Galinhas , Proteínas de Choque Térmico HSP70 , Infecções Estafilocócicas , Animais , Proteínas Aviárias/genética , Embrião de Galinha , Proteínas de Choque Térmico HSP70/genética , Infecções Estafilocócicas/veterinária , Staphylococcus aureusRESUMO
Hexavalent chromium (Cr(VI)) has carcinogenic, nephrotoxic, hepatotoxic, and neurotoxic effects. Exposure to Cr(VI) can also lead to hematological alterations and blood biochemical changes. The literature on Cr(VI) toxicity concerns mostly adult forms of vertebrates. In this study, an attempt was made to determine the effect on the developing chicken embryo of Cr(VI) in ovo administration. It was observed that chromium affected the hatchability of chicks in a dose-dependent manner. At a dose from 25 to 250 µg per egg, Cr(VI) resulted in a statistically significant reduction of hatchability. Chromium administrated at lower doses (1.56 and 2.5 µg per egg) caused a statistically insignificant increase of hatchability. However, chromium at a level of LD50 (15.6 µg per egg) or 1/10 LD50 (1.56 per egg) did not cause major changes in hematological parameters or plasma biochemical indices in newly hatched chicks. The same doses did not lead to any histopathological changes in the liver.
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Galinhas , Cromo , Fígado , Plasma , Animais , Embrião de Galinha , Cromo/toxicidade , Exposição Ambiental , Poluentes Ambientais/toxicidade , Fígado/efeitos dos fármacos , Plasma/efeitos dos fármacosRESUMO
Methionine (Met), an essential amino acid in poultry diets, when overdosed may cause hyperhomocysteinemia, which is mainly a trigger for cardiovascular diseases in humans. Homocysteine is neutralized (remethylated) in the presence of folic acid (FA), which also plays an important role in hematopoiesis and participates in the synthesis of DNA, and its deficiencies may result in the development of neural tube defects. One of the basic tools in studying the impact of both xenobiotics and nutrients on the animal organism is hematological analysis. Thus, the aim of this study was to determine the effect of in ovo supplementation with Met and FA on the hematological parameters of broiler chickens. On the 17th day of incubation, embryonated eggs (Ross 308) were injected with 5 or 25 mg of Met per egg (M5 and M25), 3 and 15 mg of FA per egg (F3 and F15), or a mixture of these 2 compounds (M5/F3 and M25/F15). The broilers were reared in accordance with welfare regulations and fed with commercial diets ad libitum. Blood samples were collected on the first, seventh, and 35th day of rearing (D1, D7, and D35), and complete hematological analysis was performed. The observed changes in red blood cell parameters probably result from physiological changes occurring during bird growth. Mean erythrocyte volume decreased with the age of chickens in the control, M5, and M25 groups, but not in those supplied with FA. Among supplemented groups, the number of white blood cells on D1 was lower only in group M5 than in the sham (C) group. The analysis of leukograms showed no significant differences between the groups. Comparing D1 with D7 in the group injected with a higher dose of Met and FA (MF25/15), a statistically significant increase in the percentage of lymphocytes and a significant decrease in the percentage of heterophils were observed. In addition, in the group injected with a higher FA dose (F15), there was statistically significant reduction in the percentage of eosinophils and a significant increase in the percentage of monocytes at day 7 compared with day 1. It seems that Met supplementation led to temporary immunosuppression in the animals.
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Galinhas , Ácido Fólico , Metionina , Zigoto , Animais , Embrião de Galinha/efeitos dos fármacos , Galinhas/sangue , Ácido Fólico/administração & dosagem , Ácido Fólico/farmacologia , Metionina/administração & dosagem , Metionina/farmacologia , Zigoto/efeitos dos fármacos , Zigoto/metabolismoRESUMO
The spatial network structure of Dergall is based on substances nontoxic to humans and the environment which, when applied on solid surfaces, creates a coating that reduces bacterial cell adhesion. The bacteriostatic properties of siloxanes are based on a purely physical action mechanism which excludes development of drug-resistant microorganisms. The aims of the present study were to 1) evaluate a Dergall layer formed on the eggshell surface regarding the potential harmful effects on the chick embryo; 2) evaluate antimicrobial activity and estimate the prolongation time of Dergall's potential antimicrobial activity. Dergall at a concentration of 0.6% formed a layer on the eggshell surface. In vitro testing of the potential harmful effects of Dergall by means of a hen embryo test of the chorioallantoic membrane showed no irritation reaction at a concentration of 3% and lower. The hatchability of the groups sprayed with a Dergall water solution with a concentration of 0 to 5% was 89.1 to 93.8% for fertilized eggs (P > 0.05) but decreased to 63.7% (P < 0.05) in the group sprayed with a 6% concentration of the solution. This phenomenon was caused by embryo mortality in the first week of incubation. At the concentration of 0.6%, Dergall exhibited strong antibacterial properties against bacteria such as Staphylococcus aureus, Escherichia coli, Shigella dysenteriae, Shigella flexneri, and Salmonella typhimurium. For Streptococcus pyogenes, the highest antibacterial activity of Dergall was reported in the concentrations of 100 and 50%. For Pseudomonas aeruginosa, no antibacterial activity of Dergall was generally observed, but in vivo testing showed a strong decrease of all gram-negative bacteria growth. Moreover, a prolonged antimicrobial effect lasting until 3 D after disinfection was observed, which makes Dergall a safe and efficient disinfectant.
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Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Embrião de Galinha/efeitos dos fármacos , Casca de Ovo/efeitos dos fármacos , Siloxanas/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Bactérias/crescimento & desenvolvimento , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Embrião de Galinha/crescimento & desenvolvimento , Galinhas , Relação Dose-Resposta a Droga , Casca de Ovo/microbiologia , Siloxanas/administração & dosagem , Siloxanas/químicaRESUMO
Fur-chewing is a common problem in chinchilla (Chinchilla lanigera). It may affect the welfare of animals due to heat loss, thereby possibly impacting food and water intake to maintain body temperature. In this context, infrared thermography seems to be a suitable method of measuring heat emissions from the surface of objects. Sexually mature male domestic chinchillas were divided into two groups: "non-fur chewers", exhibiting normal behaviour (n = 25), and "fur chewers" displaying fur-chewing behaviour (n = 23). Food and water intake (mean ± SD) measured in the control animals amounted to 20.7 ± 4.52 g and 15.9 ± 3.45 mL, while in fur-chewing chinchillas were 25% and 33% higher, respectively. Metabolic energy intake, were calculated 2.2 and 2.8 W for the control and fur-chewing animals, respectively. Heat flux through chewed areas was 6.06 mW cm-2, which is 2.8 times higher than through undamaged chinchilla fur. To sum up, thermal imagingexplicitly shows that fur-chewing causes increased heat loss. Disturbances in the maintenance of thermal homeostasis may be an additional factor that reduces the welfare of these animals.
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Pelo Animal/fisiologia , Comportamento Animal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Chinchila/fisiologia , Bem-Estar do Animal , Animais , Masculino , Mastigação , TermografiaRESUMO
The aim of this study was to evaluate ultrastructural changes in kidney and liver tissue of chicken embryos exposed in ovo to cadmium. Embryonated eggs were injected on the 4th day of incubation with cadmium at the dose of 0, 2, 4 and 8⯵g/egg (80 eggs/group). The samples of kidney and liver tissues were collected from embryos at the 14th and 18th day of incubation (E14 and E18) and at hatching day (D1). The tissue structure was evaluated by transmission electron microscopy (Tecnai G2 Spirit). The results indicate that hepatocytes responded to damage caused by toxic cadmium activity with a significant disturbance in the structure of mitochondria and a considerable expansion of the lysososmal system, while glomerular cells additionally reacted with an increased proliferation of peroxisomes. The range of changes observed on the subcellular level was dependent on the dose of cadmium, embryogenesis stage and cell type.
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Cádmio/toxicidade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Animais , Embrião de Galinha , Galinhas , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Peroxissomos/efeitos dos fármacos , Peroxissomos/metabolismoRESUMO
The phenomenon of multiple embryos in birds and other oviparous vertebrates is very rare and thus poorly studied. Some populations of wild birds or lines of poultry, including the zatorska goose, may be particularly predisposed to developing monovular twin embryos (MTE). The aim of the study was to investigate the frequency of single yolk twin embryos in the zatorska goose and to establish whether these embryos are generated as a result of polyembryony or other developmental anomalies.Embryopathological analysis, which included identification of the developmental stages of all MTEs at the time of death, was carried out on 1,955 unhatched eggs obtained from 20 pedigree breeding flocks of the zatorska goose. Post-mortem examinations revealed as many as 13 MTEs (0.66% compared to embryonated eggs) at varying developmental stages.The results of genotyping of the microsatellite loci of 7 pairs of twins demonstrated genetic similarity in 6 of them; this suggests that they developed from 1 blastoderm, while differences in 2 loci of 1 pair show that the MTE originates from 2 blastodiscs. Pedigree analysis of the MTEs does not provide evidence that predisposition toward twinning results from the genetic background. However, more frequent MTE occurrence could be seen in eggs stored for more than 8 d. It seems that embryos of the zatorska goose are more susceptible to duplication under special conditions, such as prolonged egg storage.