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1.
Poult Sci ; 94(6): 1247-58, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25825789

RESUMO

The benefits to human from the consumption of omega-3 polyunsaturated fatty acids (N-3 PUFAS) have been recognized. Camelina sativa is an oilseed crop grown for biofuel production. Feeding its cake with 10 to 20% remaining oil (28 to 30% α-linolenic acid [ALA]) has the potential to enrich poultry products with n-3 PUFA. An experiment was conducted to assess lipid deposition in brain, liver, breast, and thigh tissue by increasing inclusions of camelina cake (CC) fed to broiler chickens. Male chicks (744, Ross 308) housed in 24 cages were fed 0, 8, 16, or 24% CC for 42 d, 6 replicates per CC level. At the end of the starter (14 d), grower (28 d), and finisher (42 d) phase, brain, liver, breast, and thigh samples were collected from 3 birds/cage and diets were analyzed for fatty acid content. Feeding increasing CC inclusions from 0 to 8, 16, and 24% increased dietary ALA (5.3, 11.1, 15.2, 17.8, respectively) as a proportion of the total fatty acid content. All diets provided a similar level of long-chain n-3 PUFA (about 0.9%). Irrespective of growth phase, increases in dietary CC inclusion led to a linear increase (P<0.001) in the proportion of ALA in breast, thigh, and liver (76, 128, 288%, respectively), but not in brain tissue. An increase in dietary CC inclusion led to a linear increase (P<0.001) in the proportion of long-chain n-3 PUFAs, including docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) in liver (109 and 80%, respectively) and brain (24 and 6%, respectively) tissue. However, in breast and thigh tissue, increases in dietary CC inclusion led to an increase in only (P<0.005) DPA (24 and 27%, respectively). The predominant n-3 PUFA in liver and brain tissue feeding 24% CC was DHA (48% and 88%, respectively), unlike in breast and thigh meat, where ALA increased (65 and 86%, respectively). The labeling claim requirement for n-3 PUFA enrichment (300 mg/100 g meat) was exceeded in breast and thigh by feeding a 24% CC diet for 28 d or 16% CC diet for 42 d, respectively.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Brassicaceae/química , Galinhas/metabolismo , Dieta/veterinária , Ácidos Graxos Ômega-3/metabolismo , Ração Animal/análise , Animais , Galinhas/crescimento & desenvolvimento , Masculino , Especificidade de Órgãos , Fatores de Tempo
2.
Br Poult Sci ; 56(2): 267-74, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25633638

RESUMO

A study of broiler breeder eggs differing in eggshell matrix optical density was conducted to determine the association of eggshell structural quality and the risk of disease in broilers. A total of 10 000 eggs from a broiler breeder flock were examined according to the pre-established criteria, and allocated to groups classified as having a high or low density shell matrix. The eggs from respective groups were incubated and hatched in a commercial hatchery. Samples of unhatched eggs from each group were subjected to detailed examination to establish the cause of reproductive failure. First, quality chicks from each group were raised as separate flocks in a commercial broiler barn. Group performance, morbidity, and mortality were monitored throughout the growth period. All birds were processed in a commercial plant, and condemnation data were compiled. There were significantly more unhatched eggs, and fewer quality chicks in the group classified as having a low density eggshell matrix, in comparison to the high-density group. Embryo pathology accounted for a large proportion of the overall reproductive failure in both groups, with a large proportion of embryos showing anatomical anomalies. The eggs and embryos from the low-density eggshell matrix group were three times more likely to be infected. Significantly higher production losses associated with mortality/morbidity, and condemnations of carcasses at processing were observed in broilers from the low-density eggshell group compared with the high-density eggshell group. It is concluded that common metabolic/physiological changes in breeder hens associated with eggshell pathology may be also risk factors linked with predisposition of broiler chicks to some health problems.


Assuntos
Suscetibilidade a Doenças/veterinária , Casca de Ovo/fisiopatologia , Doenças das Aves Domésticas/fisiopatologia , Animais , Galinhas , Suscetibilidade a Doenças/epidemiologia , Suscetibilidade a Doenças/etiologia , Suscetibilidade a Doenças/fisiopatologia , Casca de Ovo/anatomia & histologia , Casca de Ovo/ultraestrutura , Microscopia Eletrônica de Varredura/veterinária , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/etiologia
3.
Poult Sci ; 91(7): 1720-32, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22700520

RESUMO

The time required to reach a plateau of n-3 polyunsaturated fatty acid (PUFA) concentration in plasma and egg yolk and dynamics of the enrichment process were examined in laying hens. A group of 75 Lohmann White Leghorn layers (65 wk) were fed one of 3 diets: control, moderate, or high n-3 PUFA-enriched diet for 18 d. Diets provided similar ME and CP and contained 0, 7.5%, or 15% LinPRO (source of n-3 PUFA), respectively. Prior to dietary treatment, baseline values were established for the BW, fatty acid composition in egg yolk on a whole-egg basis, and in plasma. These measurements were repeated at 6, 12, and 18 d of feeding. Enzymatic conversion rates of linolenic acid (LNA) to long-chain fatty acids were calculated. Data were analyzed with Proc Mixed of SAS, and broken stick analysis was used to determine n-3 PUFA plateau using the NLIN procedure of SAS (P < 0.05). The total egg yolk n-3 PUFA reached a plateau of 343.7 mg/egg and 272.9 mg/egg after 6.6 and 5.9 d on the high and moderate diets, respectively. In blood plasma, the n-3 PUFA concentrations reached saturation in 7.2 d with 0.93 mg/mL and 0.67 mg/mL on high and moderate diets, respectively. The transfer efficiency of total n-3 PUFA from the diet to the egg yolk was calculated as 55.6% in control birds, 30.5% in moderate birds, and 22.2% in high birds, demonstrating reduced transfer efficiency of n-3 PUFA as inclusion in the feed increases. Final egg yolk n-3 PUFA concentrations had a CV of 16.5% compared with 28.5% for plasma. After 12 d, the long-chain n-3 PUFA [eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA)] were significantly higher in egg yolk from hens on the moderate and high enriched diets compared with those from hens fed the control diet, whereas in plasma values did not differ. Broken stick analysis of egg enrichment indicated that high birds reached the target threshold of 300 mg of total n-3 PUFA/egg in 5 d. A significant increase in EPA, DPA, and DHA and reduction in arachidonic acid content in egg yolks from hens fed enriched diets compared with the control diet confirms competition for enzymes during postabsorptive modification of these fatty acids. This work contributes to the understanding of individual hen effects on n-3 PUFA absorption and the effect of level of dietary enrichment with an extruded flax product on final yolk n-3 PUFA concentration.


Assuntos
Ração Animal/análise , Galinhas/metabolismo , Suplementos Nutricionais , Ácidos Graxos Ômega-3/metabolismo , Linho , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/sangue , Dieta/veterinária , Relação Dose-Resposta a Droga , Gema de Ovo/química , Feminino , Oviposição
4.
Poult Sci ; 91(4): 888-98, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22399728

RESUMO

The effect of metabolic efficiency and associated gut characteristics of laying hens on the variability of transfer of dietary n-3 polyunsaturated fatty acids (PUFA) to the egg was examined in laying hens at 56 wk of age. An empirical energetics model was used to categorize individual hens into energetically efficient or nonefficient treatments based on residual maintenance ME requirement. Birds were then provided a diet containing an extruded flax product as a source of n-3 PUFA for 14 d. Egg traits were determined and yolks collected at 0 d and 14 d for measurement of fatty acid composition and variation in fatty acid levels within hen efficiency class. Gut length and duodenal histomorphometric indices were assessed after the 14-d experimental period. Efficient hens had a 96.01% rate of lay compared with 88.63% in nonefficient hens. After 14 d of feeding, the concentration of n-3 PUFA increased (151.6 vs. 315.8 mg/egg) in the egg yolk whereas n-6 PUFA, saturated fatty acids, and monounsaturated fatty acids were reduced (P < 0.001). Energetic efficiency had no additional effect on these measurements. However, egg yolks from efficient birds had less α-linolenic acid but more docosapentaenoic acid than nonefficient birds, suggesting a greater up-conversion of medium-chain (α-linolenic acid) to long-chain fatty acids (docosapentaenoic acid) in efficient birds. After 14 d, the CV for total n-3 PUFA in egg yolks from efficient hens was lower than that from nonefficient birds (11.1 vs. 21.4), indicating a more uniform level of enrichment. Furthermore, efficient hens had longer duodenal villi (P = 0.02), resulting in a greater absorptive villi surface area (0.13 mm(2)/villi) than in nonefficient birds (0.10 mm(2)/villi; P = 0.01). Increased uniformity of n-3 PUFA enrichment of table eggs could be possible through focus on metabolic efficiency and gut absorptive condition in laying hens.


Assuntos
Galinhas/anatomia & histologia , Galinhas/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Intestino Delgado/anatomia & histologia , Óvulo/metabolismo , Ração Animal/análise , Animais , Galinhas/crescimento & desenvolvimento , Ingestão de Alimentos , Gema de Ovo/metabolismo , Metabolismo Energético , Ácidos Graxos Ômega-3/análise , Feminino , Intestino Delgado/metabolismo , Óvulo/crescimento & desenvolvimento
5.
Ecotoxicology ; 20(4): 892-900, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21448623

RESUMO

The purpose of this study was to evaluate the impact of malathion on the immune system of wild birds, using Japanese quail (Coturnix coturnix japonica) as a model. Quail were exposed to malathion in drinking water at environmentally realistic concentrations (0 ppm, 1 ppm, and 10 ppm). In the fifth week, several arms of the immune response were tested using the T-cell based phytohemagglutinin (PHA) skin test, the B-cell mediated antibody response, and the chemiluminescence assay measuring innate immunity. After the sixth week of malathion exposure, quail were challenged with E. coli O2. The bursa of Fabricius and the spleen were assessed for histopathology. No clinical signs of malathion toxicity were observed. Morbidity or mortality subsequent to E. coli exposure tended (P = 0.08) to be higher in the high exposure group (50.0%) compared to the control (22.2%) group. There was no difference in the innate immune response in the malathion exposed birds, however, humoral immunity was suppressed (P = 0.03) with the higher malathion exposure. Histopathological evaluation revealed an immunosuppressive effect of malathion on the bursa of Fabricius; bursal atrophy, decreased B-cell density and increased apoptosis in the medulla, and increased connective tissue thickness of the follicular epithelium. Antibody suppression was correlated with bursal changes and peripheral blood lymphocyte count, the organ and cells involved in antibody production. Following the same pattern as other immunotoxicity tests, the PHA T-cell proliferative response also tended to be suppressed in the high exposure group. This study provides evidence that subchronic, moderate malathion exposure is immunotoxic to quail and that testing integrated, functional immunity using an infectious challenge is a better predictor of immunotoxicity than individual responses to immunotoxicity tests. The secondary antibody response, circulating lymphocyte populations, and bursal histopathology were the most sensitive indicators of immune status, as these predicted decreased disease resistance with malathion exposure.


Assuntos
Coturnix/imunologia , Sistema Imunitário/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Inseticidas/toxicidade , Malation/toxicidade , Animais , Bolsa de Fabricius/efeitos dos fármacos , Bolsa de Fabricius/imunologia , Bolsa de Fabricius/patologia , Coturnix/sangue , Coturnix/metabolismo , Relação Dose-Resposta a Droga , Infecções por Escherichia coli/imunologia , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologia , Poluentes Químicos da Água/toxicidade
6.
Ecotoxicol Environ Saf ; 74(4): 787-92, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21111478

RESUMO

The present study investigated the effects of lead (Pb) on immune responses in quail (Coturnix coturnix japonica) and the pathological impact of exposure to an infectious agent (E. coli O2). Fifty-four, 4-week-old quail were exposed to lead acetate in drinking water at 5 or 50 ppm. All birds were vaccinated with Newcastle Vaccine (NDV) during the third week of contaminant (Pb) exposure. In the fourth week, several arms of the immune response were tested using the T cell based phytohemagglutinin (PHA) skin test, the B cell mediated antibody response to NVD, and the chemiluminescence assay measuring innate immunity. Immunohistochemistry (IHC) was used to determine the expression of toll like receptor-3 (TLR-3) in the bursa of Fabricius. In the fifth week, quail were challenged with 200 µL of E. coli O2 (1×10(4) colony forming units (CFU)/mL). No clinical signs of Pb toxicity were observed. Morbidity/mortality subsequent to E. coli exposure was lowest in the high exposure group (27.8%) compared to low exposure (44.4%) and control (55.5%) groups. There was no difference in the T-cell-mediated PHA response, primary or secondary immune response or the innate response in Pb exposed groups; however, bursal TLR-3 increased (p<0.05) with higher Pb exposure. No evidence supported that subchronic Pb exposure was immunotoxic to quail at 5 or 50 ppm in drinking water. In contrast, our results provide evidence of a hormetic effect, with Pb exposed birds having lower morbidity and better survival than controls. Subchronic Pb exposure may be immunostimulatory rather than suppressive as predicted in earlier studies based on testing individual immune parameters.


Assuntos
Coturnix/imunologia , Infecções por Escherichia coli/imunologia , Imunidade Inata , Chumbo/farmacologia , Poluentes Químicos da Água/farmacologia , Adjuvantes Imunológicos/farmacologia , Animais , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Bolsa de Fabricius/efeitos dos fármacos , Bolsa de Fabricius/imunologia , Coturnix/microbiologia , Coturnix/fisiologia , Fito-Hemaglutininas/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Receptor 3 Toll-Like/metabolismo
7.
Res Vet Sci ; 86(3): 479-84, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18947843

RESUMO

This study examined the putative role of blood vessel pathology in the development of ascites in broilers. Major blood vessels (aorta, brachiocephalic arteries, pulmonary arteries, and vena cava) from normal commercial male broiler chickens, and broilers that developed congestive heart failure (CHF) with or without ascites were subjected to gross and microscopic examination. On cross-section, grossly, the arteries from normal broilers and those showing dilated cardiomyopathy without ascites appeared circular, with firm wall tone characteristic of the normal artery. In contrast, the arteries from ascitic broilers appeared flaccid and lacked elasticity, which was evidenced by collapsing, ellipsoid cross-sectional arterial lumen owing to the structural weakness of the arterial walls. Microscopically, ascitic broilers showed thinning or occasionally total loss of elastic elements in the arterial wall, and reduced network density of the structural matrix of the vascular wall, as well as increased thickness of fibers in vena cava. The structural changes seen in the major arteries from ascitic broilers are maladaptive, and as such would definitively impose an increased hemodynamic burden on the already failing heart pump. The changes in veins are indicative of pathological remodeling conducive to increased permeability of the vascular wall, particularly in the situation when a poorly distensible structure is further subjected to wall stress associated with increased pressure and volume overload. Taken together, increased hemodynamic burden and reduced structural density of the venous wall constitute conditions conducive for seepage and accumulation of ascitic fluid.


Assuntos
Ascite/veterinária , Vasos Sanguíneos/patologia , Doenças das Aves Domésticas/patologia , Animais , Aorta/patologia , Aorta/ultraestrutura , Ascite/mortalidade , Ascite/patologia , Galinhas/crescimento & desenvolvimento , Elasticidade , Crescimento/fisiologia , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/veterinária , Microscopia Eletrônica de Varredura , Doenças das Aves Domésticas/mortalidade , Estudos Retrospectivos , Análise de Sobrevida , Veia Cava Inferior/patologia , Veia Cava Inferior/ultraestrutura
8.
Br Poult Sci ; 49(6): 697-704, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19093242

RESUMO

1. It has recently been shown that oxidative stress is involved in the pathogenesis of congestive heart failure (CHF) in broiler chickens. Vitamins E and C, common antioxidants, have been advocated for the prevention of heart failure in humans. The present study examines the effects of supplementation of these vitamins on incidence of CHF and prevention of oxidative stress in the myocardium. 2. Commercial male broilers were randomly allocated to three experimental groups and, respectively, offered commercial broiler diet (control), commercial diets fortified with vitamin E (960 IU/kg) or vitamin C (400 mg/kg). The broilers were monitored daily for overt signs of heart failure and clinical data including ECG and blood gas analysis were collected periodically. Lipid peroxidation was measured in cardiac tissues from apparently normal broilers and broilers developing CHF in each group using thiobarbituric acid reactive substances (TBARS) assay. 3. Overall, the incidence of CHF in broilers given diets fortified with vitamin E or vitamin C was not significantly different as compared to the control group. The incidence of overt signs of hypoxaemia was lower in the vitamin C group than in the control group. Lipid peroxidation was highest in broilers that developed CHF as compared to apparently normal broilers fed either vitamin E or C fortified diets. Neither vitamin E nor vitamin C was effective in preventing oxidative damage in broilers that developed CHF. 4. In conclusion, the present study confirmed that oxidative stress is involved in the pathogenesis of heart failure in broilers, but dietary supplementation of antioxidant vitamins did not prevent oxidative damage in broilers that developed CHF. Beneficial effects of vitamin C supplementation were evidenced by lower incidence of hypoxaemia, and the tendency to reduce the susceptibility of broilers to heart failure. However, vitamin E did not have any impact on clinical status or the incidence of CHF.


Assuntos
Ácido Ascórbico/uso terapêutico , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Insuficiência Cardíaca/veterinária , Doenças das Aves Domésticas/prevenção & controle , Vitamina E/uso terapêutico , Vitaminas/uso terapêutico , Animais , Gasometria , Galinhas/fisiologia , Eletrocardiografia , Insuficiência Cardíaca/prevenção & controle , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos
9.
Avian Pathol ; 37(6): 605-12, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18923962

RESUMO

Thermal processing of meat products generates cardiotoxic compounds capable of inducing heart failure in both humans and laboratory animals. Such compounds may be present in broiler diets because supplements such as meat meal (MM), which are commonly used in broiler rations, are rendered at high temperature. Our objective was to evaluate whether putative cardiotoxic compounds in MM increase the risk of heart failure in broilers. The treatment and control diets were prepared by mixing the condensed MM extract (equivalent to dietary MM inclusion of 25%) or placebo (condensed extraction medium) with commercial broiler feed, and the respective diets were offered to commercial male broilers randomly allocated to either treatment or control groups. Broilers fed a diet spiked with MM extract showed a higher incidence (P<0.05) of chronic heart failure (65.5%) in comparison with the control group (55.4%). Postmortem examination upon termination of the experiment revealed that, in comparison with control broilers, broilers fed diet containing MM extract showed higher incidence of lesions indicative of subclinical heart disease evidenced grossly by ventricular dilation and pericardial effusions, microscopically by changes characteristic of cardiomyocyte degeneration, and ultrastructurally by changes in contractile elements and in mitochondria. Measurements of cardiac high-energy phosphates revealed that broilers fed the diet containing MM extract had lower (P<0.05) levels of cardiac energy reserve as compared with birds fed control diet. We conclude that cardiotoxic factors that can induce patho-physiological changes in the heart are present in MM.


Assuntos
Galinhas/crescimento & desenvolvimento , Insuficiência Cardíaca/veterinária , Produtos da Carne/efeitos adversos , Doenças das Aves Domésticas/induzido quimicamente , Ração Animal/análise , Animais , Doença Crônica , Dieta/veterinária , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/patologia , Masculino , Produtos da Carne/análise , Miocárdio/patologia , Miocárdio/ultraestrutura , Fatores de Risco
10.
Avian Pathol ; 37(4): 367-73, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18622851

RESUMO

The present study examined the possible role of reactive oxygen species in the pathogenesis of heart failure in broilers. Data were collected from three groups of birds at various risk of heart failure: Leghorn chickens (resistant to heart failure), slow-growing feed-restricted broilers (low risk of heart failure), fast-growing ad libitum fed broilers (high risk of heart failure), and broilers with congestive heart failure (CHF). In the first part of the study, basic clinical parameters and ultrastructural changes were examined in the context of lipid peroxidation of the ventricular myocardium. This was followed by the study of in vitro changes in the activity of selected cytosolic enzymes (creatine kinase and lactate dehydrogenase) and mitochondrial enzymes (pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase) in the presence of oxidants (hydrogen peroxide or tertiary butyl hydroperoxide). The distinctive clinical feature in the fast-growing broilers and in the broilers with CHF as compared with slow-growing broilers or Leghorn chickens was a significantly lower heart rate (P <0.05). Electron microscopy revealed marked morphological changes in myocardial mitochondria in these broilers (i.e. fast-growing broilers and broilers with CHF). The level of malondialdehyde equivalents, an indicator of lipid peroxidation subsequent to generated oxidative stress, was significantly higher (P <0.05) in ad libitum fed broilers and was highest (P <0.01) in broilers with CHF. In vitro, the presence of oxidants had a detrimental effect on creatine kinase and alpha-ketoglutarate dehydrogenase activity, while lactate dehydrogenase activity increased. The activity of pyruvate dehydrogenase was not altered by oxidants. Our results indicate that the deterioration of heart function in fast-growing commercial broilers in our experimental model is associated with oxidative stress leading to lipid peroxidation of cellular and mitochondrial membranes, and decreased activity of myocardial creatine kinase and alpha-ketoglutarate dehydrogenase enzymes critical for energy synthesis and transformation pathways.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/genética , Predisposição Genética para Doença , Insuficiência Cardíaca/veterinária , Estresse Oxidativo/genética , Doenças das Aves Domésticas/genética , Animais , Privação de Alimentos , Insuficiência Cardíaca/genética , Frequência Cardíaca , Incidência , Miocárdio/enzimologia
11.
Res Vet Sci ; 85(1): 131-40, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17904171

RESUMO

Sudden death syndrome (SDS) in fast growing broiler chickens has been recognized as a patho-physiological entity for four decades, but its pathogenesis still remains unknown. More recent investigations provided evidence that link SDS to cardiac arrhythmia, but the mechanism triggering arrhythmogenesis and factors responsible for fatal outcome are poorly understood. In order to understand the chain of events leading to SDS in broilers, the present study focused on putative mechanisms that trigger arrhythmia and mechanisms that predispose the myocardium to fatal arrhythmia. Susceptibility of broilers to cardiac arrhythmia under stress conditions was evaluated using a simulated stress test with epinephrine. Detailed histopathological evaluation of the broiler heart was undertaken to identify structural features that may predispose the myocardium to fatal arrhythmia. The simulated stress challenge revealed that many broilers are highly susceptible to stress induced cardiac arrhythmia. In some broilers the stress challenge induced severe ventricular arrhythmia, and the life threatening nature of this arrhythmia was evidenced by the fact that several birds showing the most severe arrhythmic responses, died suddenly within several days after the stress challenge. Examination of hearts of broilers that died of SDS revealed microscopic lesions in the cardiomyocytes, and widespread changes in the sub-endocardial and mural His-Purkinje system (HPS). Immune staining for Caspase-3 confirmed that numerous Purkinje cells in the left ventricular myocardium from broiler chickens that died of SDS were undergoing apoptosis. The observed lesions suggest that the electrical stability of the myocardium was compromised. Taken together, our findings indicate that stress is a most likely trigger of cardiac arrhythmia in broilers, whereas the pathological changes seen in the myocardium and in the HPS in fast growing broilers provide a very conducive milieu for sustained ventricular arrhythmia. In cases where the electrical stability of the myocardium is compromised, even an episodic arrhythmic event may readily degenerate to catastrophic ventricular fibrillation and sudden death. We conclude that the combination of stress and changes in the cardiomyocytes and HPS are the key requisite features in the pathogenesis of SDS.


Assuntos
Galinhas , Morte Súbita/veterinária , Doenças das Aves Domésticas/etiologia , Animais , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/veterinária , Morte Súbita/etiologia , Epinefrina/farmacologia , Miocárdio/patologia , Doenças das Aves Domésticas/epidemiologia , Estresse Fisiológico/induzido quimicamente
12.
Artigo em Inglês | MEDLINE | ID: mdl-17988909

RESUMO

Broiler chickens (Gallus gallus) genetically selected for rapid growth are inherently predisposed to heart failure. In order to understand the biochemical mechanisms associated with the deterioration of heart function and development of congestive heart failure (CHF) in fast-growing chickens, this study examined several factors critical for myocardial energy metabolism. Measured variables included cardiac energy substrates [creatine phosphate (CrP), adenosine triphosphate (ATP), l-carnitine], activity of selected cytosolic enzymes [creatine kinase (CK; EC 2.7.3.2), lactate dehydrogenase (LDH; EC 1.1.1.27)] and mitochondrial enzymes [pyruvate dehydrogenase (PDH; EC 1.2.4.1), alpha-ketoglutarate dehydrogenase (alpha-KGDH; EC 1.2.4.2)]. The CK activities were higher in fast-growing and CHF broilers as compared to slow-growing broilers (p<0.05). Cardiac LDH and alpha-KGDH activities were not changed (p>0.05), whereas PDH activity was highest (p<0.05) in broilers with CHF. Deterioration of heart function is correlated with lowered cardiac ATP, CrP, and l-carnitine levels (all p<0.05). Depletion of high energy phosphate substrates, ATP and CrP, is evident in fast-growing chickens and those that developed CHF. Increased activity of CK suggests that cardiac energy management in fast-growing broilers and those with CHF largely depends on contribution of this pathway to regeneration of ATP from CrP. In this scenario, inadequate level of CrP is a direct cause of ATP insufficiency, whereas low cardiac l-carnitine, because of its role in fatty acid transport, is most likely an important factor contributing to shortage of key substrate required for synthesis of cardiac ATP. The insufficiencies in cardiac energy substrate synthesis provide metabolic basis of myocardial dysfunction in chickens predisposed to heart failure.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/genética , Coração/crescimento & desenvolvimento , Miocárdio/metabolismo , Animais , Dióxido de Carbono/sangue , Galinhas/metabolismo , Genótipo , Coração/fisiologia , Frequência Cardíaca , Masculino , Microscopia Eletrônica de Transmissão , Miocárdio/ultraestrutura , Oxigênio/sangue , Fatores de Tempo
13.
Artigo em Inglês | MEDLINE | ID: mdl-17936051

RESUMO

Broiler diets are frequently fortified with vitamin D (D3) above the recommended levels in an attempt to prevent commonly occurring leg problems. Since the basal levels of dietary D3 are rarely known, there is a risk of over-supplementation. Over-supplementation of D3 has been shown to have detrimental effects on the heart. Sudden death syndrome (SDS) is a condition commonly observed in broiler flocks and is associated with acute heart failure. The present study examines the effects of excessive levels of vitamin D3 on cardiac health in fast growing broiler chickens. Commercial male broilers (Gallus gallus) were exposed to either a commercial diet or a commercial diet supplemented with D3. Throughout the trial all birds were monitored several times daily for overt signs of heart disease, and periodically electrocardiographic measurements were obtained. Morbidity and mortality data were collected daily. On day 32 a simulated stress challenge consisting of a single injection of epinephrine (100 microg/kg BW) was administered under continuous ECG monitoring. Broilers fed the high D3 diet were 2.5 fold more likely to succumb to acute heart failure and die of SDS (p<0.05). Electrocardiographic examination showed a higher rate of cardiac arrhythmia in birds fed the high D3 diet (22.6%), in comparison to those fed the control diet (11.8%). The stress challenge test revealed that broilers exposed to high dietary D3 were more susceptible to ventricular arrhythmia. Our findings indicate that over-supplementation of vitamin D increases the risk of SDS in broilers, and that the most likely mechanism is associated with increased susceptibility of the ventricular myocardium to arrhythmia.


Assuntos
Suplementos Nutricionais , Doenças das Aves Domésticas/mortalidade , Vitamina D/efeitos adversos , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/mortalidade , Galinhas , Eletrocardiografia , Teste de Esforço , Frequência Cardíaca , Masculino , Miocárdio/patologia , Fatores de Risco , Fatores de Tempo
14.
Artigo em Inglês | MEDLINE | ID: mdl-17524693

RESUMO

In order to explain the biochemical mechanisms associated with deteriorating heart function in broiler chickens, this study compared myocardial high energy phosphate substrates in leghorns, feed restricted (Broilers-Res) broilers, ad libitum fed broilers (Broilers-AL), and in broilers that developed heart failure and ascites. The profile of adenine nucleotide content in the heart tissue did not differ between leghorns and Broilers-Res, but there were significant differences among Broilers-Res, Broilers-AL, and broilers with ascites. During intensive growth periods, leghorns and Broilers-Res showed increasing trends in heart ATP levels, whereas in fast growing broilers the heart ATP declined (p<0.021). ATP:ADP and ATP:CrP ratios increased with age in both leghorn and Broilers-Res, declined in fast growing broilers, and were the lowest in broilers that developed heart failure. The changes in heart high energy phosphate profile in broilers suggest that the energy demand of the heart during a rapid growth phase may exceed the bird's metabolic capacity to supply adequate levels of high energy phosphate substrate. The insufficiency of energy substrate likely contributes to the declining heart rate. In some individuals this may lead to impaired heart pump function, and in more severe cases may progress to heart pump failure.


Assuntos
Ascite/metabolismo , Baixo Débito Cardíaco/metabolismo , Galinhas/crescimento & desenvolvimento , Miocárdio/metabolismo , Fosfatos/metabolismo , Animais , Eletrocardiografia , Metabolismo Energético
15.
In. III Congresso Latino Americano de Engenharia Biomédica - CLAEB / International Federation for Medical and Biological Engineering - IFMBE Proceedings. Anais. João Pessoa, SBEB, 2004. p.201-204, 1 CD-ROM - III Congresso Latino Americano de Engenharia Biomédica - CLAEB / International Federation for Medical and Biological Engineering - IFMBE Proceedings, ilus, tab, graf.
Monografia em Português | LILACS | ID: lil-540462

RESUMO

In this research a preliminary behavioral evaluation was accomplished with subjects of the species Rattus novergicus submitted since gestation, to microwave radiation in several frequencies during one hour daily...


Assuntos
Animais , Masculino , Ratos , Micro-Ondas , Exposição à Radiação , Ratos , Estresse Fisiológico
16.
Can J Anaesth ; 41(4): 288-90, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8004732

RESUMO

Arterial oxygen saturation (SpO2) was measured to determine oxygen desaturation during peripheral venous cannulation prior to induction of anaesthesia in 40 consecutive patients in each of the three age groups; Group I: 1-4 mo, Group II: 4-12 mo, Group III: 12-24 mo. Following premedication with oral trimeprazine tartarate 3 mg.kg-1, one to two hours before operation, baseline SpO2 was noted with child breathing room air. Continuous monitoring during peripheral venous cannulation was done and maximum decrease and duration of SpO2 < 90% was noted. Decreases in mean SpO2, 3.2 +/- 1.4 in Group I, 2.6 +/- 2.0 in Group II and 1.7 +/- 1.9 in Group III, were observed (P < 0.001). Desaturation > or = 4% was noted in 17 patients in Group I, ten patients in Group II and six patients in Group III. Two children, one each in Groups I and II, experienced SpO2 < 90% for 30 sec and 80 sec respectively. We conclude that clinically undiagnosed desaturation occurs during peripheral venous cannulation in healthy children. The authors suggest that continuous monitoring of SpO2 using pulse oximetry should be performed routinely during peripheral venous cannulation.


Assuntos
Anestesia Geral , Cateterismo Periférico , Oxigênio/sangue , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Lactente , Masculino , Oximetria
17.
Vet Res ; 24(3): 278-85, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8343812

RESUMO

In order to determine the exact localization (intra- vs intermuscular) in which a drug is injected when administered by a so-called intramuscular injection technique, a radiopaque test article (2 ml) was injected into the cervical musculature (2 sites), the loins and the gluteal mass in anaesthesized pigs. Immediately after this, the pigs were euthanized and deep-frozen. Then they were cut into slices, which were X-rayed to determine the exact localization of the test material. Semi-quantitative scores were given to each injection site according to the amount of test article found in or out of muscle mass and also to the absence or the presence of test article subcutaneously. The loins area obtained the highest score for intramuscular location, but in this site, injections were almost always followed by a flowing back of the test article to the subcutaneous' area. It was shown that an injection in the neck perpendicular to the skin surface just behind the base of the ear was the most appropriate site for intramuscular injection in pigs.


Assuntos
Meios de Contraste/administração & dosagem , Injeções Intramusculares/veterinária , Músculos/metabolismo , Suínos/metabolismo , Análise de Variância , Animais , Nádegas , Meios de Contraste/farmacocinética , Região Lombossacral , Músculos/diagnóstico por imagem , Pescoço , Radiografia
18.
Anc Sci Life ; 11(3-4): 118-25, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22556573

RESUMO

Nilgiri District, Tamil Nadu is one of the most botanised areas of Southern India. In spite of it a number of wild plants had been missed by earlier collectors. Moreover, many exotics and ornamentals having importance in alternative systems of medicine have not been collected and preserved. The present paper lists 34 species of plants used in homeopathy belonging to 31 genera under 23 families.

19.
Anc Sci Life ; 11(1-2): 78-93, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22556568

RESUMO

Nilgiri District, Tamil Nadu is one of the most botanised areas of southern India. In spite of it a number of wild plants had been missed by previous collectors. In addition a number of exotics and ornamentals having importance in alternative systems of medicine like Homoeopathy and Unani have not been collected and preserved as herbarium records. The present paper lists 36 species of wild plants and 69 species of exotics. Their areas of occurrence, phonological data, accession numbers, and names of collectors have been given.

20.
J Obstet Gynaecol India ; 29(3): 644-6, 1979 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12335922

RESUMO

PIP: Lipid metabolism of women on combination oral contraceptives (OCs) (Lynestrenol and Primovlar ED) was studied. Serum lipids of 15 women on OCs for less than 5 years and 39 on OCs for more than 5 years were compared with each other and also with a control group of 22 women, in whom basal readings were obtained before starting the study. No significant changes were obtained in women on OCs for total lipids, esterified cholesterol, triglycerides, and alpha- and beta-lipoproteins. A significant rise (P .05) in total serum cholesterol was observed in women on OCs for more than 5 years as compared with the control group. A significant rise was also seen in free cholesterol in both groups of OC users as compared with controls (P .05).^ieng


Assuntos
Fatores Etários , Anticoncepcionais Femininos , Anticoncepcionais Orais Combinados , Anticoncepcionais Orais , Etinilestradiol , Lipídeos , Linestrenol , Mestranol , Norgestrel , Paridade , Estudos Prospectivos , Biologia , Coeficiente de Natalidade , Anticoncepção , Anticoncepcionais , Anticoncepcionais Orais Hormonais , Demografia , Serviços de Planejamento Familiar , Fertilidade , Fisiologia , População , Características da População , Dinâmica Populacional , Pesquisa
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