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131.
The effect of supplementing layer diets with shark cartilage or chitosan on egg components and yolk lipids 总被引:1,自引:0,他引:1
Nogueira CM Zapata JF Fuentes MF Freitas ER Craveiro AA Aguiar CM 《British poultry science》2003,44(2):218-223
1. An experiment was designed to evaluate the effects of the addition of shark cartilage (SC) or chitosan (CH) to layer diets on egg component weights, yolk lipids and hen plasma lipids. 2. Hy-Line laying hens (80) were used during a 56 d feeding trial. Treatments were: basal diet (BD), BD + 20 g/kg SC, BD + 30 g/kg SC, BD + 20 g/kg CH and BD + 30 g/kg CH. Eggs were analysed on d 14, 28, 42 and 56. 3. Egg weight and egg component weights were not affected by these treatments throughout the experimental period. 4. After 14d of experimental feeding, cholesterol levels were higher in eggs from birds given BD + 20 g/kg CH and BD + 30 g/kg CH than in those from birds given BD. 5. Furthermore, eggs from hens given BD + 20 g/kg SC or BD + 20 g/kg CH were higher in palmitic and stearic acids and lower in oleic acid than those from birds fed on BD. After 56 d feeding, however, palmitic and stearic acid contents in eggs from hens given any of the supplemented diets were lower than in those from hens given BD, and oleic acid in eggs from hens given BD + 20 g/kg SC, BD + 30 g/kg SC and BD + 30 g/kg CH was higher than in those from birds fed on BD. 6. Plasma cholesterol and triacylglycerol levels were not significantly affected by dietary treatment. 7. Shark cartilage or chitosan at up to 30 g/kg in layer diets did not affect egg component weights (yolk, white and shell) and total lipid contents. During the period from 42 to 56d of experimental feeding, diets containing up to 30 g/kg chitosan reduced egg yolk contents of cholesterol, palmitic and stearic acids and increased the content of oleic acid. 相似文献
132.
OBJECTIVE: To compare Doppler echocardiographic variables of left ventricular (LV) function with those obtained invasively via cardiac catheterization under a range of hemodynamic conditions. ANIMALS: 7 healthy anesthetized cats (1 to 3 years of age). PROCEDURE: Cats were anesthetized and instrumented to measure the time constant of isovolumic relaxation (tau [tau]), LV end-diastolic pressure (LVEDP), peak negative and positive rate of change of LV pressure, arterial blood pressure, and cardiac output. Echocardiographic variables of diastolic function (isovolumic relaxation time [IVRT], early LV flow propagation velocity [Vp], transmitral and pulmonary venous flow velocity indices, and LV tissue Doppler imaging indices) were measured simultaneously over a range of hemodynamic states induced by treatments with esmolol, dobutamine, cilobradine, and volume loading. Correlation between invasive and noninvasive measures of LV filling was determined by univariate and multivariate regression analyses. RESULTS: Significant correlations were found between tau and IVRT, peak Vp, peak late transmitral flow velocity, and peak systolic pulmonary venous flow velocity. A significant correlation was found between LVEDP and early diastolic transmitral flow velocity (peak E) and the ratio of peak E to peak Vp, but not between LVEDP and peak Vp. CONCLUSIONS AND CLINICAL RELEVANCE: IVRT and Vp can be used as noninvasive indices of LV relaxation; Vp was independent of preload and heart rate in this study. The E:Vp ratio may be useful as an indicator of LV filling pressure. 相似文献
133.
Koplitz SL Meurs KM Spier AW Bonagura JD Fuentes VL Wright NA 《Journal of the American Veterinary Medical Association》2003,222(6):770-774
OBJECTIVE: To determine aortic ejection velocity in healthy adult Boxers with soft ejection murmurs without overt structural evidence of left ventricular outflow tract obstruction and in healthy Boxers without cardiac murmurs. DESIGN: Retrospective study. ANIMALS: 201 Boxers. PROCEDURE: Dogs were examined independently by 2 individuals for evidence of a cardiac murmur, and a murmur grade was assigned. Maximal instantaneous (peak) aortic ejection velocity was measured by means of continuous-wave Doppler echocardiography from a subcostal location. Forty-eight dogs were reexamined approximately 1 year later. RESULTS: A soft (grade 1, 2, or 3) left-basilar ejection murmur was detected in 113 (56%) dogs. Overall median aortic ejection velocity was 1.91 m/s (range, 1.31 to 4.02 m/s). Dogs with murmurs had significantly higher aortic ejection velocities than did those without murmurs (median, 2.11 and 1.72 m/s, respectively). Auscultation of a murmur was 87% sensitive and 66% specific for the identification of aortic ejection velocity > 2.0 m/s. An ejection murmur and aortic ejection velocity > 2.0 m/s were identified in 73 (36%) dogs. For most dogs, observed changes in murmur grade and aortic ejection velocity during a follow-up examination 1 year later were not clinically important. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ejection murmurs were common among healthy adult Boxers and that Boxers with murmurs were likely to have high (> 2.0 m/s) aortic ejection velocities. The cause of the murmurs in these dogs is unknown. 相似文献
134.
Moneva-Jordan A Corcoran BM French A Dukes-McEwan J Martin MW Luis Fuentes V Hitchcock LS Bonagura JD 《The Veterinary record》2001,148(5):142-147
Sick sinus syndrome is a clinical term used to describe the clinical signs of sinus node dysfunction. This paper describes the clinical data from nine West Highland white terriers, eight females and one male, in which a diagnosis of sick sinus syndrome was made. The most common clinical signs were episodic weakness and presyncope. Electrocardiographic findings included sinus bradycardia, sinus arrest with or without escape complexes, disturbances of atrioventricular conduction, paroxysmal supraventricular tachycardia, or some combination of these dysrhythmias. The main radiographic changes were mild right-sided cardiomegaly in five cases, and a slight increase in bronchial and interstitial markings in four, but there was no evidence of congestive heart failure in any of the dogs. Echocardiography revealed mild to moderate mitral endocardiosis in three cases with no other significant abnormalities. The dogs' responses to parenteral atropine were variable and were not necessarily related to their response to oral anticholinergic agents. Five of the dogs were initially treated with propantheline bromide, but in only two of them were the clinical signs controlled in the long term. Six of the dogs were successfully treated by the implantation of a transvenous pacemaker. 相似文献
135.
Assessment of balloon pulmonary valvuloplasty in six dogs 总被引:1,自引:0,他引:1
M. W. S. Martin M. Godman V. Luis Fuentes R. E. Clutton A. Haight P. G. G. Darke 《The Journal of small animal practice》1992,33(9):443-449
The effectiveness of balloon valvuloplasty was assessed, clinically and haemodynamically, in six dogs with moderate to severe pulmonic stenosis. The haemodynamic assessment was based on Doppler echocardiography, with colour flow mapping, in the conscious dog and by direct catheterisation in the anaesthetised dog, before and after balloon valve dilatation. Four of the six dogs were presented with exercise intolerance, of which two were in congestive heart failure. Balloon valvuloplasty resulted in improved exercise tolerance and resolution of congestive heart failure in these dogs. The average Doppler and catheter transvalvular pressure gradients were reduced to 43 per cent and 46 per cent of the preoperative gradient, respectively. The average pressure gradient obtained by catheter, in the anaesthetised dog, was 59 per cent of the pressure gradient obtained by spectral Doppler echocardiography in the conscious dog. Balloon valvuloplasty was considered successful in five out of the six dogs. Postoperative pulmonic regurgitation was not found to be a complication of balloon valvuloplasty. 相似文献
136.
Toxoplasmosis gondii causes one of the most common zoonoses worldwide. The rate in Panama is one of the highest in the world. Infections are primarily asymptomatic in immune competent individuals; however, in immunocompromised patient and congenital cases can be lethal. Exposure to the pathogen is hypothesized to occur when handling or consuming infected food such as swine meat. In this study, we analyzed 290 swine sera collected from six provinces in Panama by Indirect Immunofluorescence antibody test (IFAT) against T. gondii. Toxoplasma-specific IgG were found in 32.1% of the samples. The highest seroprevalence was found in the province of Panama. 相似文献
137.
Circulating natriuretic peptides in cats with heart disease 总被引:1,自引:0,他引:1
Connolly DJ Magalhaes RJ Syme HM Boswood A Fuentes VL Chu L Metcalf M 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(1):96-105
BACKGROUND: Circulating natriuretic peptide concentrations are increased in cats with myocardial dysfunction. HYPOTHESIS: Serum N-terminal fragment of proatrial natriuretic peptide (NT-proANP) and NT-probrain natriuretic peptide (proBNP) concentrations may predict the presence of heart disease (HD) and congestive heart failure (CHF). A positive relationship is also predicted among natriuretic peptide (NP) concentrations, a noninvasive estimate of left ventricular filling pressure (E/E(a)), and an echocardiographic measure of left atrial (LA) size (LA/aortic diameter [Ao]). METHODS: Serum NP concentrations were measured in 28 healthy control and 50 study cats using sandwich enzyme immunoassays. The study group comprised cats, with HD but no CHF (HD - CHF, n = 17) and cats with CHF (HD + CHF, n = 33). The relationship among NP concentrations, LA size, and E/E(a) was examined. The ability of NP to distinguish control from study cats, and HD - CHF from HD + CHF cats, was explored using receiver operator curve analysis. RESULTS: NP concentrations were significantly lower in control than in study cats (P= .0001). The NT-proBNP concentrations were positively correlated with LA/Ao ratio (rho= 0.34; P= .02) and with E/E(a) ratio (rho= 0.68; P < .05). An NT-proBNP concentration of 49 fmol/mL gave a sensitivity and specificity of 100 and 89.3%, respectively, for correctly distinguishing 96.2% of control from study cats. Pairwise comparisons of the areas under the curve identified a statistically significant difference (P= .011) between NT-proANP and NT-proBNP to distinguish control from study cats. NT-proANP and NT-proBNP concentrations were significantly higher in HD + CHF cats than in HD - CHF cats (P= .0023 and .0001, respectively). CONCLUSIONS: Serum concentrations of NT-proANP and particularly NT-proBNP were different in healthy control cats, asymptomatic cats with HD, and cats with CHF, suggesting that measurement of NP concentrations may prove clinically useful as an initial screening test for cats with suspected cardiac disease. 相似文献
138.
Analysis of murmur intensity, duration and frequency components in dogs with aortic stenosis 总被引:1,自引:0,他引:1
C. Kvart A. T. French V. Luis Fuentes J. Häggström J. Dukes McEwan K. E. Schober † 《The Journal of small animal practice》1998,39(7):318-324
A study was undertaken to investigate the relationship between murmur intensity, murmur duration, duration to peak intensity and frequency components with degree of aortic stenosis in boxers. Measurements were made from phonocardiograms obtained from 35 boxers with ejection-type murmurs, and values were compared with those obtained for aortic flow velocity measured by Doppler echocardiography. Murmur intensity graded by auscultation was significantly correlated with aortic flow velocity (P<0·001), and murmur duration, expressed as a percentage of systole, was significantly correlated with aortic flow velocity (P<0·001), independent of heart rate. Dogs with early systolic murmurs not exceeding 50 per cent of systole had aortic flow velocities of less than 1·5 m/second and no echocardiographic abnormalities, in contrast with dogs with murmurs of longer duration. Dogs with only high frequency components had lower aortic velocities than those that also had components in the medium frequency range (P<0·01). 相似文献
139.
140.