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1.
Br Poult Sci ; 63(6): 768-778, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35899553

RESUMO

1. Litter quality has been related to broiler performance, behaviour, welfare, dust and ammonia (NH3) emissions. Drier litter leads to a reduction in NH3 emissions and reduces the formation of foot- and hock lesions. However, maintaining good litter quality is often challenging. This study investigated the effects of different bedding materials on litter quality and NH3 concentrations at litter level, broiler performance, foot- and hock lesions, plumage cleanliness and breast skin irritation.2. A total of 2160 Ross 308 male broilers were randomly assigned to 36 floor pens. There were six replications for each of the following six litter treatments: wood shavings, flax, peat, maize silage, chopped wheat straw and flax pellets.3. For the total period, the highest feed intake and body weight was obtained for broilers housed on peat. The NH3 concentrations measured at litter level was highest for peat and chopped wheat straw at 36 d of age and numerically the lowest for flax at 30 and 36 d of age. Maize silage remained friable, but did not result in lower NH3 concentrations compared to wood shavings. Chopped wheat straw and wood shavings gave rise to the highest incidence of foot lesions at 38 d of age, while broilers kept on flax, peat, maize silage and flax pellets had the lowest incidence of foot lesions at the end of the rearing period.4. The results of the current study suggest a complicated relationship between the type of bedding material, litter conditions and NH3 volatilised from the litter.


Assuntos
Amônia , Galinhas , Animais , Masculino , Abrigo para Animais , Peso Corporal , Pisos e Cobertura de Pisos , Solo
2.
Neth Heart J ; 28(Suppl 1): 108-114, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32780340

RESUMO

Out-of-hospital cardiac arrest (OHCA) is a major cause of death. Although the aetiology of cardiac arrest can be diverse, the most common cause is ischaemic heart disease. Coronary angiography and percutaneous coronary intervention, if indicated, has been associated with improved long-term survival for patients with initial shockable rhythm. However, in patients without ST-segment elevation on the post-resuscitation electrocardiogram, the optimal timing of performing this invasive procedure is uncertain. One important challenge that clinicians face is to appropriately select patients that will benefit from immediate coronary angiography, yet avoid unnecessary delay of intensive care support and targeted temperature management. Observational studies have reported contradictory results and until recently, randomised trials were lacking. The Coronary Angiography after Cardiac Arrest without ST-segment elevation (COACT) was the first randomised trial that provided comparative information between coronary angiography treatment strategies. This literature review will provide the current knowledge and gaps in the literature regarding optimal care for patients successfully resuscitated from OHCA in the absence of ST-segment elevation and will primarily focus on the role and timing of coronary angiography in this high-risk patient population.

3.
Acta Oncol ; 58(2): 243-250, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30523729

RESUMO

PURPOSE/OBJECTIVE: Flank irradiation for Wilms' tumor (WT) is currently performed at our institute using a cone-beam computed tomography-guided volumetric modulated arc (VMATCBCT) workflow. By adding real-time magnetic resonance imaging (MRI) guidance to the treatment, safety margins could be reduced. The study purpose was to quantify the potential reduction of the planning target volume (PTV) margin and its dosimetric impact when using an MRI-guided intensity modulated radiation therapy (IMRTMRI) workflow compared to the VMATCBCT workflow. MATERIAL/METHODS: 4D-CT, MRI and CBCT scans acquired during preparation and treatment of 15 patients, were used to estimate both geometric, motion and patient set-up systematic (∑) and random (σ) errors for VMATCBCT and IMRTMRI workflows. The mean PTV (PTVmean) expansion was calculated using the van Herk formula. Treatment plans were generated using five margin scenarios (PTVmean ± 0, 1 and 2 mm). Furthermore, the IMRTMRI plans were optimized with a 1.5T transverse magnetic field turned-on to realistically model an MRI-guided treatment. Plans were evaluated using dose-volume statistics (p<.01, Wilcoxon). RESULTS: Analysis of ∑ and σ errors resulted in a PTVmean of 5 mm for the VMATCBCT and 3 mm for the IMRTMRI workflows in each orthogonal direction. Target coverage was unaffected by the margin decrease with a mean V95%=100% for all margin scenarios. For the PTVmean, an average reduction of the mean dose to the organs at risk (OARs) was achieved with IMRTMRI compared to VMATCBCT: 3.4 ± 2.4% (p<.01) for the kidney, 3.4 ± 2.1% (p<.01) for the liver, 2.8 ± 3.0% (p<.01) for the spleen and 4.9 ± 3.8% (p<.01) for the pancreas, respectively. CONCLUSIONS: Imaging data in children with WT demonstrated that the PTV margin could be reduced isotropically down to 2 mm when using the IMRTMRI compared to the VMATCBCT workflow. The former results in a dose reduction to the OARs while maintaining target coverage.


Assuntos
Neoplasias Renais/radioterapia , Imageamento por Ressonância Magnética , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Tumor de Wilms/radioterapia , Criança , Pré-Escolar , Terapia Combinada , Tomografia Computadorizada de Feixe Cônico , Fracionamento da Dose de Radiação , Feminino , Tomografia Computadorizada Quadridimensional , Humanos , Lactente , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Masculino , Órgãos em Risco , Estudos Retrospectivos , Tumor de Wilms/tratamento farmacológico , Tumor de Wilms/patologia , Tumor de Wilms/cirurgia
4.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e615-e622, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29030884

RESUMO

The effect of dietary particle size on gastrointestinal transit in carnivores has not been studied and might offer more insight into their digestive physiology. This study evaluated the effect of two dietary particle sizes (fine = 7.8 mm vs. coarse = 13 mm) of chunked day-old chicks on transit parameters in dogs. Six beagle dogs were fed both dietary treatments in a crossover design of 7 days with transit testing on the fifth day. Transit parameters were assessed using two markers, that is a wireless motility capsule (IntelliCap® ) and titanium oxide (TiO2 ). Dietary particle size did not affect gastric emptying time (GRT), small bowel transit time (SBTT), colonic transit time (CTT) and total transit time (aTTT) of the capsule (p > .05). There was no effect of dietary particle size on TiO2 mean retention time (MRT) (p > .05). The time of last TiO2 excretion (MaxRT) differed (p = .013) between diets, being later for the coarse diet. Both MRT (R = 0.617, p = .032) and MaxRT (R = 0.814; p = .001) were positively correlated to aTTT. The ratio MRT/aTTT tended towards a difference between diets (p = .059) with the coarse diet exceeding fine diet values. Results show that the difference between capsule measurements and TiO2 is larger for the fine than the coarse diet suggesting that the capsule becomes more accurate when dietary particle size approaches marker size. Dietary particle size might have affected transit parameters but differences are too small to claim major physiological consequences.


Assuntos
Ração Animal/análise , Dieta/veterinária , Manipulação de Alimentos , Trânsito Gastrointestinal/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Estudos Cross-Over , Cães , Feminino , Masculino , Tamanho da Partícula
5.
J Anim Physiol Anim Nutr (Berl) ; 101(3): 429-433, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27868252

RESUMO

The trace element selenium is essential to both dogs and cats. Dry diets are formulated with a large range of ingredients, which may vary in selenium concentration and accessibility. This paper reports equations to predict the average in vitro selenium accessibility from dry pet foods based on essential dietary nutrient concentrations, including crude protein, amino acids and crude fat. Predictive equations were made using stepwise linear regression for extruded and pelleted diets. The equations can be used to aid diet formulation to optimize selenium accessibility within the diet and to prevent selenium deficiency or toxicity.


Assuntos
Ração Animal/análise , Análise de Alimentos/métodos , Animais de Estimação , Selênio/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Disponibilidade Biológica , Gatos , Cães , Alimentos em Conserva , Oligoelementos
6.
Clin Genet ; 90(2): 105-17, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26662178

RESUMO

Ataxia-telangiectasia (AT) is an autosomal recessive neurodegenerative disorder with immunodeficiency and an increased risk of developing cancer, caused by mutations in the ataxia-telangiectasia mutated (ATM) gene. Logically, blood relatives may also carry a pathogenic ATM mutation. Female carriers of such a mutation have an increased risk of breast cancer. Other health risks for carriers are suspected but have never been studied systematically. Consequently, evidence-based guidelines for carriers are not available yet. We systematically analyzed all literature and found that ATM mutation carriers have a reduced life expectancy because of mortality from cancer and ischemic heart diseases (RR 1.7, 95% CI 1.2-2.4) and an increased risk of developing cancer (RR 1.5, 95% CI 0.9-2.4), in particular breast cancer (RRwomen 3.0, 95% CI 2.1-4.5), and cancers of the digestive tract. Associations between ATM heterozygosity and other health risks have been suggested, but clear evidence is lacking. Based on these results, we propose that all female carriers of 40-50 years of age and female ATM c.7271T>G mutation carriers from 25 years of age onwards be offered intensified surveillance programs for breast cancer. Furthermore, all carriers should be made aware of lifestyle factors that contribute to the development of cardiovascular diseases and diabetes.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Ataxia Telangiectasia/genética , Neoplasias da Mama/genética , Neoplasias Gastrointestinais/genética , Mutação , Isquemia Miocárdica/genética , Adulto , Ataxia Telangiectasia/complicações , Ataxia Telangiectasia/diagnóstico , Ataxia Telangiectasia/patologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Medicina Baseada em Evidências , Feminino , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/etiologia , Neoplasias Gastrointestinais/patologia , Expressão Gênica , Aconselhamento Genético , Predisposição Genética para Doença , Heterozigoto , Humanos , Expectativa de Vida , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/patologia , Guias de Prática Clínica como Assunto , Fatores de Risco
7.
Poult Sci ; 95(5): 1066-76, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26908893

RESUMO

The non-starch polysaccharides (NSPs) in cell walls can act as a barrier for digestion of intracellular nutrients. This effect is called "cage effect." Part of the success of fibrolytic enzymes in broiler feed is assumed to be attributed to cage effect reduction. Further, changes in viscosity and potential prebiotic action should also be considered. The aim of this study was to gain insight into the relative importance of the cage effect in xylanase efficacy in broilers. Using a 2×2 factorial design, 24 pens with 30 Ross 308 male chicks were fed corn-soy based diets consisting of normal and freeze-thawed (5 d at -18°C) corn, both with and without xylanase. The freeze-thaw method was used to eliminate the cage effect, whereas a corn-based diet was used to exclude viscosity effects. Body weights (BW), feed intake (FI), and feed conversion ratio (FCR) were determined at d 13, 26, and 39. A balance study was executed at the end of the growing phase. These birds were euthanized at d 34 (non-fasted) to determine the viscosity of digesta, blood metabolites, intestinal morphology, and microbiota composition. During the finisher period, there was a significant interaction between enzyme supplementation and freeze-thawing for FCR, in which FCR was improved by freeze-thawed corn and tended to be improved by normal corn+enzyme compared with the control group. The improvement in performance (finisher period) of freeze-thawed corn and xylanase coincided with increased gut absorption of glucose (based on postprandial plasma concentrations) and increased number of Clostridiumcluster IV in the caecum, and agreed with the higher gut villus height. In addition, xylanase inclusion significantly increased the postprandial plasma glycine and triglycerides concentration, and led to elevated bacterial gene copies of butyryl CoA:acetate CoA-transferase, suggesting a prebiotic effect of xylanase addition through more than just the cage effect reduction. The applied model managed to rule out viscosity by using corn, and it was possible to isolate the cage effect by freeze-thawing the dietary corn.


Assuntos
Ração Animal/análise , Galinhas , Dieta/veterinária , Endo-1,4-beta-Xilanases/farmacologia , Manipulação de Alimentos/métodos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Congelamento , Masculino
8.
J Anim Physiol Anim Nutr (Berl) ; 99(3): 531-41, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24990384

RESUMO

Small-scale urban dairy farms (n = 16) in and around Jimma, Ethiopia with cross-bred (Bos indicus × Bos taurus) cows were enrolled in a double-blinded intervention study to investigate the effect of a trace element supplementation programme on trace element status and milk concentrations as well as performance [body condition score (BCS), milk yield, leptin], milk composition, antioxidant status (ferric-reducing ability of plasma (FRAP), thiobarbituric acid-reactive substances (TBARS)], blood biochemistry, serum proteins and immune response (antibody titre upon rabies vaccination). The farms were allocated to a (1) placebo or (2) Cu, Zn, Se, Co and I supplementation treatment for 150 d. On days 0 and 120, four lactating cows per farm were sampled for milk and plasma, and on day 150 for serum, following primo-vaccination. Cu deficiency was present in 17% and marginal Se deficiency in 30% of initially sampled cows, while no Zn shortage was detected. Over 120 days, trace element supplementation caused a bigger increase in plasma Se and Cu concentrations, but also a larger decrease of plasma Fe concentrations. A larger increase in milk Se concentrations was observed in the supplemented group, whereas none of the other elements were affected. BCS decreased more over time in the supplemented group. None of the other parameters of performance and antioxidant status nor milk composition or blood biochemistry was affected by treatment. Antibody response to rabies vaccination did not differ between groups, whereas α1-globulins tended to be lower and ß-globulins tended to be higher in the supplemented group. In conclusion, despite improved Cu and Se status and Se concentrations in milk, cows on tropical urban dairy farms did not seem to benefit from trace element supplementation, with respect to the parameters investigated.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Oligoelementos/farmacologia , Ração Animal/análise , Criação de Animais Domésticos , Animais , Antioxidantes/metabolismo , Análise Química do Sangue , Proteínas Sanguíneas/química , Dieta/veterinária , Método Duplo-Cego , Leite/química , Raiva/prevenção & controle , Raiva/veterinária , Vacina Antirrábica/imunologia , Oligoelementos/administração & dosagem , Clima Tropical
9.
Fish Physiol Biochem ; 41(1): 281-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25549626

RESUMO

This study was executed to investigate the effect of dietary ß-alanine (BA) on amino acid (AA) metabolism and voluntary feed intake in carp (Cyprinus carpio) at mildly elevated temperature to exert AA catabolism. Twenty-four fish in 12 aquaria were randomly assigned to either a control diet or the same diet with 500 mg BA/kg. A 14-day period at an ideal temperature (23 °C) was followed by 15 days at chronic mildly elevated temperature (27 °C). After the 15 days, all fish were euthanised for muscle analysis on histidine-containing dipeptides (HCD), whole blood on free AA and carnitine esters. The carnosine and anserine analysis indicated that all analyses were below the detection limit of 5 µmol/L, confirming that carp belongs to a species that does not store HCD. The increases in free AA concentrations due to BA supplementation failed to reach the level of significance. The effects of dietary BA on selected whole blood carnitine esters and their ratios were also not significant. The supplementation of BA tended to increase body weight gain (P = 0.081) and feed intake (P = 0.092). The lack of differences in the selected nutrient metabolites in combination with tendencies of improved growth performance warrants further investigation to unravel the mechanism of BA affecting feed intake. This first trial on the effect of BA supplementation on AA catabolism showed that its metabolic effect in carp at chronic mildly elevated temperature was very limited. Further studies need to evaluate which conditions are able to exert an effect of BA on AA metabolism.


Assuntos
Aminoácidos/metabolismo , Carpas/metabolismo , Dieta , Redes e Vias Metabólicas/fisiologia , Temperatura , beta-Alanina/metabolismo , Análise de Variância , Animais , Peso Corporal/fisiologia , Carnosina/metabolismo , Dipeptídeos/metabolismo , Histidina/metabolismo , Músculo Esquelético/metabolismo
10.
J Anim Physiol Anim Nutr (Berl) ; 98(3): 417-23, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23510054

RESUMO

The effect of supplementing leaves of four tannin-rich plant species with polyethylene glycol 6000 (PEG) on nutrient intake and digestibility as well as on weight gain, feed conversion ratio (FCR) and N retention of zebu bulls (Bos indicus) was studied. Leaves of Albizia gummifera, Grewia ferruginea, Prunus africana and Syzygium guineense, containing, respectively, 85, 55, 76 and 172 g condensed tannins (CT) per kg dry matter (DM), were combined with natural pasture hay in a ratio of 40:60 on DM basis. The four diets were fed both without and with addition of PEG, at a dose of 40 g per kg DM, to eight zebu bulls during trials of 25 days in an 8 × 8 randomized crossover design. Supplementation with PEG increased nutrient intake, digestibility, FCR, N retention and average daily gain (p < 0.01). A diet × PEG interaction was observed for nutrient intake as well as for crude protein, neutral detergent fibre and acid detergent fibre digestibility (p < 0.05), but the effect size of PEG addition could not be attributed to the CT content as such, and also digestibility without PEG was not related to CT content of the diets. The reason why the efficacy of PEG addition did not relate to the CT content pointed the need to evaluate other factors that can help to predict the efficacy of PEG, for example, tannin type or interaction with other nutrients.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Digestão/efeitos dos fármacos , Folhas de Planta/química , Polietilenoglicóis/farmacologia , Taninos/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Estudos Cross-Over , Dieta/veterinária , Suplementos Nutricionais , Masculino , Folhas de Planta/metabolismo , Polietilenoglicóis/química
11.
Br J Nutr ; 110(7): 1326-35, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23702152

RESUMO

According to human research, the location of fat accumulation seems to play an important role in the induction of obesity-related inflammatory complications. To evaluate whether an inflammatory response to obesity depends on adipose tissue location, adipokine gene expression, presence of immune cells and adipocyte cell size of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were compared between lean and obese cats. Additionally, the present study proposes the cat as a model for human obesity and highlights the importance of animal models for human research. A total of ten chronically obese and ten lean control cats were included in the present study. Body weight, body condition score and body composition were determined. T-lymphocyte, B-lymphocyte, macrophage concentrations and adipocyte cell size were measured in adipose tissue at different locations. Serum leptin concentration and the mRNA expression of leptin and adiponectin, monocyte chemoattractant protein-1, chemoligand-5, IL-8, TNF-alpha, interferon-gamma, IL-6 and IL-10 were measured in blood and adipose tissues (abdominal and inguinal SAT, and omental, bladder and renal VAT). Feline obesity was characterised by increased adipocyte cell size and altered adipokine gene expression, in favour of pro-inflammatory cytokines and chemokines. Consequently, concentration of T-lymphocytes was increased in the adipose tissue of obese cats. Alteration of adipose tissue was location dependent in both lean and obese cats. Moreover, the observed changes were more prominent in SAT compared with VAT.


Assuntos
Adipocinas/metabolismo , Distribuição da Gordura Corporal , Citocinas/metabolismo , Inflamação/etiologia , Gordura Intra-Abdominal/metabolismo , Obesidade/complicações , Gordura Subcutânea/metabolismo , Adipócitos/metabolismo , Adipócitos/patologia , Adipocinas/sangue , Adipocinas/genética , Animais , Gatos , Quimiocinas/genética , Quimiocinas/metabolismo , Citocinas/genética , Modelos Animais de Doenças , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/veterinária , Obesidade/genética , Obesidade/metabolismo , Obesidade/veterinária , RNA Mensageiro/metabolismo , Valores de Referência , Linfócitos T/metabolismo
12.
J Anim Physiol Anim Nutr (Berl) ; 97(4): 624-31, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22487253

RESUMO

The relation between plasma leptin and daily ad libitum roughage intake was evaluated during a 14-day period in eight obese Shetland ponies. When the feeding strategy was changed from maintenance feeding to ad libitum feeding, feed intake increased the first day, decreased the second day and increased again during the following days to reach a constant level after 8 days. Plasma leptin concentration increased during the first 2 days, but remained constant afterwards. Although the same pattern was found in all ponies, the magnitude of the increase in leptin on day 1 and the resulting decrease in feed intake on day 2 differed between ponies. A lower anorectic effect was seen in ponies with higher initial leptin concentration, suggesting the presence of different degrees in leptin sensitivity in obese ponies. High leptin production in a attempt to compensate for the decrease in leptin sensitivity might explain large variations in plasma leptin among obese ponies with similar body condition score. Further research is necessary to clarify whether the reduced leptin sensitivity precedes obesity in equines or vice versa.


Assuntos
Ingestão de Alimentos , Privação de Alimentos/fisiologia , Doenças dos Cavalos/metabolismo , Leptina/metabolismo , Obesidade/veterinária , Animais , Cavalos , Leptina/sangue , Masculino , Obesidade/metabolismo , Projetos Piloto , Fatores de Tempo
13.
J Anim Physiol Anim Nutr (Berl) ; 97(1): 146-54, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22074361

RESUMO

As wild felids are obligate carnivores, it is likely that poorly enzymatically digestible animal tissues determine hindgut fermentation, instead of plant fibre. Therefore, faecal concentrations of short-chain fatty acids (SCFA, including branched-chain fatty acids, BCFA), indole and phenol were evaluated in 14 captive cheetahs, fed two different diets differing in proportion of poorly enzymatically digestible animal tissue. Using a cross-over design, the cheetahs were fed exclusively whole rabbit or supplemented beef for 1 month each. Feeding whole rabbit decreased faecal propionic (p < 0.001) and butyric (p = 0.013) acid concentrations, yet total SCFA was unaltered (p = 0.146). Also, a remarkably higher acetic acid to propionic acid ratio (p = 0.013) was present when fed whole rabbit. Total BCFA (p = 0.011) and putrefactive indole (p = 0.004) and phenol (p = 0.002) were lower when fed whole rabbit. Additionally, serum indoxyl sulphate, a toxic metabolite of indole, was analysed and showed a quadratic decrease (p = 0.050) when fed whole rabbit. The divergent SCFA ratios and the decrease in putrefaction when fed whole rabbit could be caused by the presence of undigested tissue, such as skin, bone and cartilage, that might have fibre-like functions. The concept of animal fibre is an unexplored area of interest relevant to gastrointestinal health of captive cheetahs and likely other felids.


Assuntos
Acinonyx , Ração Animal/análise , Dieta/veterinária , Fibras na Dieta , Carne/análise , Acinonyx/sangue , Acinonyx/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais de Zoológico , Bovinos , Fibras na Dieta/administração & dosagem , Fibras na Dieta/classificação , Feminino , Fermentação , Indicã/sangue , Masculino , Coelhos
14.
Amino Acids ; 43(1): 245-53, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21912862

RESUMO

The current study first investigates the emulsifying potential of glycine and its N-methylated derivatives N-methylglycine (sarcosine), N,N-dimethylglycine (DMG) and N,N,N-trimethylglycine (betaine) under varying pH conditions. Subsequently, the effect of these test compounds on the membrane integrity of enterotoxigenic Escherichia coli (ETEC) was evaluated. Oil in water emulsions containing each compound show that DMG is a more potent enhancer of emulsification than glycine, sarcosine and betaine under the conditions tested. Flow cytometry was used to investigate whether the emulsifying potential is associated with an effect on ETEC membrane integrity. The bacteria were exposed to each of the test compounds under varying pH conditions and membrane integrity was assessed using the LIVE/DEAD BacLight kit. Results show a membrane deteriorating effect caused by glycine, sarcosine and DMG, but not by betaine. This effect is pH- and time-dependent and has an apparent threshold at pH 9.0. Conventional plate counts confirmed concomitant changes in culturability of the membrane comprised bacteria.


Assuntos
Membrana Celular/efeitos dos fármacos , Emulsificantes/farmacologia , Escherichia coli Enterotoxigênica , Glicina/farmacologia , Glicinas N-Substituídas/farmacologia , Betaína/farmacologia , Membrana Celular/fisiologia , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Escherichia coli Enterotoxigênica/fisiologia , Concentração de Íons de Hidrogênio , Sarcosina/análogos & derivados , Sarcosina/farmacologia
15.
J Anim Physiol Anim Nutr (Berl) ; 96(6): 1084-90, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22074297

RESUMO

A feeding trial was conducted to evaluate the effects of mannanoligosaccharides (MOS) on nutrient digestibility, intestinal pH, gut morphology and faecal bacteriology of pigeons, as model for birds without functional caeca. Sixteen adult pigeons (Columba livia domestica) were randomly allotted to either an extruded pellet diet with or without 0.4% MOS. After an adaptation period of 24 days, excreta were collected during 4 days. Apparent nutrient digestibility coefficients were determined using total collection method. Further, excreta pH was measured and percentage of uric acid determined. Fresh excreta were cultured for measurement of colony-forming units for Escherichia coli. At the end, the gastrointestinal tract (GIT) was excised and pH measurements performed on the separate GIT sections. Finally, pancreas, liver, gizzard and abdominal fat pad were weighed, and standardised segments of duodenum and jejunum were removed for microscopic measurement of crypt depth, villus height and muscularis thickness. Feed intake and water intake were similar between control diet and MOS diet. Intestinal pH was unaffected by MOS supplementation; however, excreta pH was significantly lower in pigeons on the MOS diet. Although nutrient digestibility was similar between treatments, uric acid content of excreta was significantly higher in the MOS group in relation to the control group. Further, duodenal crypt depth, villus height and muscularis thickness, as well as jejunal muscularis thickness were all significantly reduced by MOS supplementation. No effect of MOS supplementation was seen on the counts of E. coli. Furthermore, despite marked differences on both GIT morphology and uric acid content of excreta, apparent digestibility coefficients, and organ weights, were similar between treatments. It is suggested that the MOS-induced changes on gut morphology and the reduced excreta pH reflect a reduced bacterial challenge in the intestine of pigeons. Supplementation of MOS, therefore, has potential as prebiotic strategy in birds without functional caeca.


Assuntos
Ração Animal/análise , Columbidae , Dieta/veterinária , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Mananas/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Intestinos/fisiologia , Mananas/química , Prebióticos
16.
J Anim Physiol Anim Nutr (Berl) ; 96(6): 1054-64, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21895780

RESUMO

In six normal-weight and six obese cats, the metabolic effect of propionate absorbed from the colon was assessed. Two colonic infusions were tested in a crossover design with intervals of 4 weeks. The test solution contained 4 mmol sodium propionate per kg ideal body weight in a 0.2% NaCl solution. Normal saline was given as control solution. Solutions were infused into the hindgut over 30 min. Blood samples were obtained prior to and at various time points after starting the infusion. As body condition did not affect evaluated parameters, all data were pooled. Plasma glucose concentrations showed differences neither over time nor during or after infusion with propionate or control. Plasma amino acid concentrations rose over time (p < 0.001), but were similar for both infusions. Plasma propionylcarnitine rose markedly towards the end of the propionate infusion and decreased afterwards (p < 0.001), whereas 3-hydroxy-3-methylglutarylcarnitine was lower 30 (p = 0.005) and 60 min (p = 0.032) after ending propionate infusions and acetylcarnitine tended to fall at the same time points (p = 0.079; p = 0.080), suggesting inhibition of gluconeogenesis from pyruvate and amino acids, but initiation of propionate-induced gluconeogenesis. In conclusion, propionate absorbed from the colon is hypothesized to act as gluconeogenic substrate, regardless of the cat's body condition.


Assuntos
Ração Animal/análise , Gatos/metabolismo , Colo/metabolismo , Dieta/veterinária , Gluconeogênese/fisiologia , Propionatos/farmacocinética , Absorção , Fenômenos Fisiológicos da Nutrição Animal , Animais , Estudos Cross-Over , Feminino , Masculino , Obesidade , Propionatos/metabolismo
17.
Zoo Biol ; 31(6): 629-41, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22052742

RESUMO

This study evaluated nutrient intake and relevant blood parameters of 14 captive cheetahs, randomly assigned to a meat-only diet (supplemented beef, SB) or a whole prey diet (whole rabbit, WR) for 4 weeks each. Despite a higher food intake, daily metabolizable energy intake was lower when fed WR (308 kJ BW(-1) ) compared with SB (347 kJ BW(-1) ) (P = 0.002). The ratio of protein to fat was markedly lower for WR (2.3:1) compared with SB (8.8:1), which was reflected in higher serum urea levels when fed SB (P = 0.033), and a tendency for elevated cholesterol levels when fed WR (P = 0.055). Taurine intake of cheetahs fed WR was low (0.06% on DM basis); however, analytical error during taurine analysis cannot be ruled out. Feeding WR resulted in a well-balanced mineral intake, in contrast to SB. The latter provided a low calcium:phosphorus ratio (1:2.3), thereby increasing the risk of metabolic bone disease. The high zinc content of SB (200 mg/kg DM), compared with WR (94 mg/kg DM), was reflected in higher serum zinc concentrations (P = 0.011). Feeding WR resulted in an increase in serum vitamin A (P = 0.011). Therefore, the risk of hypervitaminosis A in captive cheetahs when fed WR exclusively on a long-term basis should be evaluated. Our findings suggest that neither diet is likely to provide appropriate nutrition to captive cheetahs when fed exclusively.


Assuntos
Acinonyx/sangue , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais , Carne/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais de Zoológico , Bovinos , Minerais/sangue , Coelhos , Valores de Referência
18.
Phys Med ; 95: 1-8, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35051680

RESUMO

Independent dose verification with Monte Carlo (MC) simulations is an important feature of proton therapy quality assurance (QA). However, clinical integration of such tools often generates an additional and complex workload for medical physicists. The preparation of the necessary clinical inputs, such as the machine beam model, should therefore be automated. In this work, a methodology for automatic MC commissioning has been devised, validated, and developed into a MATLAB tool for the users of myQA iON, the recent QA platform of IBA Dosimetry. With this workflow, all necessary parameters can easily be tuned using dedicated optimization methods. For the geometrical beam parameters (phase space), the assumption of a single or double Gaussian is made. To model the energy spectrum, a Gaussian function is assumed and parameters are optimized using either MC simulations or a library of pre-computed Bragg peaks. For the absolute dose calibration, commissioning fields can be reproduced with the dose engine to retrieve the necessary parameters. We discuss in a first time the tool efficiency and show that one can optimize all parameters in less than 4 min per energy with excellent accuracy. We then validate a beam model obtained with the tool by simulating homogeneous spread-out Bragg peaks (SOBPs) and patient QA plans previously measured in water. An average range agreement of 0.29 ± 0.34 mm is achieved for the SOBPs while 3%/3 mm local gamma passing rates reach 99.3% on average over all 62 measured patient QA planes, which is well within clinical tolerances.


Assuntos
Método de Monte Carlo , Terapia com Prótons , Planejamento da Radioterapia Assistida por Computador , Humanos , Terapia com Prótons/métodos , Radiometria/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
19.
J Anim Physiol Anim Nutr (Berl) ; 95(1): 34-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20487096

RESUMO

The effect of starch gelatinisation degree in extruded feed on intestinal morphology, intestinal pH and faecal bacteriology was investigated in pigeons. Extruded complete pigeon diets would offer the principle advantage of providing equilibrated nutrients and energy, but factors such as starch gelatinisation require investigation before these diets are offered as main dietary items to pigeons. Birds were fed two diets with equal ingredient composition and nutrient content, but with a different degree of starch gelatinisation resulting from altered extrusion processing (high gelatinisation degree (HG) with 73.6% gelatinisation vs. low gelatinisation degree (LG) with 53.1% gelatinisation). Feed intake and weight gain changes were measured weekly. Blood samples were collected at day 28 and analysed for non-esterified fatty acids, lactate dehydrogenase and glucose. The pH values for fresh excreta were measured; thereafter fresh excreta were collected and cultured for measurement of colony-forming units for bacterial classes. At the end, morphological measurements were examined and the pH values throughout the gastrointestinal tract were recorded. Liver, pancreas and abdominal fat were weighed. There was a tendency (p= 0.07) towards higher numbers of Escherichia coli in the excreta of the LG group compared with those in the HG group. No dietary treatment effects were noted on the number of Lactobacillus sp. in the excreta. In proximal parts of the intestine, LG revealed a significantly lower pH than HG. Villus height and crypt depth were not affected by dietary treatment, but the duodenum muscularis thickness, liver weight and pancreas weight were significantly lower in the LG than that in HG group. This trial demonstrated that the lower level of starch gelatinisation degree of extruded feed leads to acidification of the proximal gut and altered gut morphology in pigeons. Hence, extruded pigeon diets should preferably contain low-gelatinised starch instead of high-gelatinised starch. In addition, future research must focus on the effects of starch gelatinisation on the correlation between the intestinal pH, microflora content and intestinal morphology.


Assuntos
Columbidae/anatomia & histologia , Columbidae/fisiologia , Intestinos/anatomia & histologia , Intestinos/microbiologia , Amido/química , Amido/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Intestinos/fisiologia , Masculino
20.
J Anim Physiol Anim Nutr (Berl) ; 95(2): 146-53, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20666863

RESUMO

The effect of dietary supplementation with N,N-dimethylglycine sodium salt (Na-DMG) was evaluated in a feeding trial with 1500 1-day-old broiler chicks (Cobb 500). DMG was supplemented at 0, 0.1, 0.2, 0.5 or 1 g Na-DMG/kg feed to a ration with either animal fat (chicken fat) or vegetal fat (soy oil) as main fat source. In the vegetal fat diets, production value was significantly linearly improved by supplementation with DMG up to 11%. Irrespective of dietary fat source, abdominal fat percentage was significantly linearly reduced up to 24% and meat yield tended to increase linearly with DMG level up to 4%. In the vegetal fat groups, DMG significantly lowered abdominal fat pad by up to 38% and tended to increase meat yield up to 6% at the highest dose. Fasted non-esterified fatty acid level significantly decreased with increasing DMG level up to 36% and thiobarbituric acid reactive species (TBARS) decreased with a statistical trend up to 46% at the highest dose. In vegetal fat diets, addition of DMG resulted in significant lower TBARS level by 56% at the highest dose. Finally, a significant quadratic effect on ascites heart index was present in the vegetal fat diets, with a minimal value at 0.5 g Na-DMG/kg. In conclusion, dietary supplementation with DMG may improve technical and slaughter performance, and may reduce oxidative stress and pulmonary hypertension, but the degree of effects is modulated by fatty acid profile of the diet. Herewith, effects are more pronounced in a diet rich in polyunsaturated fatty acids compared with a diet rich in saturated and monounsaturated fatty acids.


Assuntos
Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Gorduras na Dieta/farmacologia , Suplementos Nutricionais , Ácidos Graxos/farmacologia , Sarcosina/análogos & derivados , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Dieta/veterinária , Gorduras na Dieta/análise , Relação Dose-Resposta a Droga , Ácidos Graxos/química , Feminino , Hipertensão Pulmonar/prevenção & controle , Hipertensão Pulmonar/veterinária , Masculino , Doenças das Aves Domésticas/prevenção & controle , Sarcosina/farmacologia , Óleo de Soja/química , Óleo de Soja/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico
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