Bone fracture incidence in end-of-lay high-producing, noncommercial laying hens identified using radiographs.

Bone fractures in laying hens are both a welfare and an economic concern for the poultry industry. The aim of this study was to use radiographs to quantify fracture incidence in 6 lines of noncommercial high-producing laying hens. A total of 451 hens (n = 71 to 78) were killed at 47 wk (White Leghorn-Black, White Leghorn-Blue) or 65 wk of age [Barred Plymouth Rock (BR), White Leghorn-Burgundy (WL-BUR), Columbian Plymouth Rock, Rhode Island Red (RIR)]. Radiographs were obtained with hens in 2 positions (lateral and ventrodorsal) and were used to identify fractures in the skeleton. Data on scallop-shaped indentations (possibly fractures) of the keel bone were also collected. After radiography, the left wings were removed for analysis of humeri, radii, and ulnae. Data for the 2 age groups were analyzed separately. The overall incidence of hens with at least 1 fracture was 6.6 and 15.7% in the 47- and 65-wk-old hens, respectively. Fracture incidence in 47-wk-old hens was not different between White Leghorn-Black and White Leghorn-Blue lines. Significant line differences were observed in the 65-wk-old hens, with at least 1 fracture found in 29.5% of RIR hens versus 9.5 and 4.2% observed in Columbian Plymouth Rock and WL-BUR lines, respectively. Fracture incidence in BR hens (18.2%) was greater than in WL-BUR hens. Fractures in RIR hens occurred predominantly in the furculum and wing bones, whereas pubic bones were most affected in BR hens. The proportion of hens with scallop-shaped indentations of the keel ranged from 36.1 to 88.2% and differed between lines in both age groups. High egg production did not seem to be associated with bone fragility in these lines. Two of the older lines (RIR and WL-BUR) had similar egg production, number of eggs to 60 wk, and egg shell weights at 4 ages but had a significantly different fracture incidence. The line differences in fracture incidence may have been affected by calcium metabolism, bone structure, and body weight.

Radiodensity in the central cavity of humeri in high-producing non-commercial laying hens.

1. Line differences in the incidence of the presence of radiodense material in the central cavities of humeri of 6 different lines of laying hens were observed using radiographs. 2. Internal humeral radiodense material was observed in over 60% of hens in two lines and 18% of hens in two other lines measured at 65 weeks of age. There was no difference in the incidence (15, 16%) between the last two lines observed at 47 weeks of age. 3. In the 4 lines studied at 65 weeks of age the presence of radiodense material was associated with increased humerus dry weight and ash weight in two lines, while percentage-ash was reduced in all 4 lines. 4. Results from this and previous studies suggest that humeral medullary bone could be an appreciable source of variability in experimental data collected to assess skeletal health.

Fiber-coupler-based measurement of lenslet focal lengths.

In a technique reminiscent of the classic autocollimation method, we demonstrate that focal lengths of micro-optic lenses may be measured precisely by the use of a mirror and a 2 × 1 fiber coupler.

Prevalence of gastrointestinal nematodes in dairy heifers in western Canada.

A survey was conducted to estimate the prevalence of gastrointestinal nematodes in grazing dairy replacement heifers in western Canada. Fecal samples were collected from 566 animals on 34 farms distributed over the three prairie provinces. Fecal egg counts were performed using a modified Wisconsin centrifugation technique. The overall mean farm fecal egg count was 16.0 eggs per gram feces (range 0.7-78.1 epg). Gastrointestinal nematodes were demonstrated on every farm examined, and 93.3% of all individuals tested were positive.

Importance of stenosis morphology in the estimation of restenosis risk after elective percutaneous transluminal coronary angioplasty.

To determine the importance of predilatation stenosis morphology on the risk of restenosis after percutaneous transluminal coronary angioplasty (PTCA), 500 procedures were randomly chosen for analysis from 3,839 consecutive successful PTCA procedures. Angiographic follow-up was available for 308 patients (62%) at a mean of 7.3 +/- 3.4 months after PTCA. One dilated site was randomly chosen per procedure. One hundred and one sites had documented restenosis (greater than or equal to 50% mean diameter stenosis from multiple projections) by quantitative angiography (33% of all sites restudied and 20% of all sites dilated). Twenty-eight morphologic variables and 20 other angiographic, clinical and procedural variables were analyzed by an observer blinded to clinical outcome. Univariate analysis found post-PTCA percent stenosis greater than 30% (p = 0.005), bend point location (p = 0.01), post-PTCA gradient greater than 15 mm Hg (p = 0.02), angina class III to IV (p = 0.03), age (p = 0.04) and the absence of dissection (p = 0.04) to predict restenosis. Multivariate analysis found only 2 significant (p less than 0.05) independent predictors of restenosis: post-PTCA percent stenosis greater than 30% and bend point location. Restenosis occurred in 41% of lesions located at an end-diastolic vessel angle greater than or equal to 45 degrees compared with 28% in lesions on lesser bends. Thus, only 1 predilatation morphologic characteristic, stenosis location at a bend point, was an important independent predictor of restenosis, and should be considered when assessing patients for PTCA.

Angiographic and clinical predictors of acute closure after native vessel coronary angioplasty.

To determine predictors of acute coronary closure after PTCA performed with steerable catheter systems, we compared 140 procedures complicated by acute closure and 311 representative successful attempts from 4,772 procedures performed between April 1982 and March 1986. Sixteen clinical, 35 angiographic, and seven procedural variables were analyzed. Multivariate analysis found seven independent preprocedural factors related to closure: stenosis length of 2 or more luminal diameters, female gender, stenosis at a bend point of 45 degrees or more, stenosis at a branch point, stenosis-associated thrombus (filling defect or staining), other stenoses in the same vessel, and multivessel disease. In addition, four procedural factors were found to be associated with closure by univariate analysis: post-PTCA percent stenosis (p less than .001), intimal tear or dissection (p less than .001), use of prolonged heparin infusion (p less than .001), and post-PTCA gradient of 20 mm Hg or more (p = .004). Multivariate analysis of both preprocedural and procedural variables found six factors independently related to closure: post-PTCA percent stenosis, dissection, prolonged post-PTCA use of heparin, branch point location, fixed bend point location, and other stenoses in the vessel dilated. The risk of coronary closure after PTCA has many determinants. While an estimation of risk can be made before performing PTCA, the most powerful predictors of closure can only be assessed during the procedure itself.

Measurement of transstenotic pressure gradient during percutaneous transluminal coronary angioplasty.

Obstruction to blood flow is accompanied by a pressure gradient across the obstructed site. In certain clinical settings, magnitude of pressure gradient has been used to judge severity of obstruction, and gradient reduction to judge success of an interventional procedure. In percutaneous transluminal coronary angioplasty (PTCA) the relationships between transstenotic pressure gradient, diameter stenosis, and lesion length are imprecisely known. We therefore examined 4263 sets of measurements in patients who underwent PTCA on single, discrete coronary arterial lesions. Multivariate regression analysis demonstrated that pressure gradient was artifactually elevated by about 12 mm Hg at low values of diameter stenosis but increased by the 4th power of stenosis as expected from fluid dynamics models. Pressure gradient was dampened and relatively constant at values of diameter stenosis of 60% or higher, probably because of total or near-total occlusion of the artery. Lesion length was not found to influence pressure gradient. Reductions in diameter stenosis (delta D) and pressure gradient (delta G) were related nonlinearly, with delta D proportional to the square root of delta G, suggesting that a reduction in gradient is directly proportional to an increase in cross-sectional area of the stenosis. The predictive value of final post-PTCA pressure gradients was found: a final gradient of 15 mm Hg or less predicted a final post-PTCA diameter stenosis of 30% or less, with 75% sensitivity and 29% specificity (p less than .01). The results of this study suggest that (1) pressure gradient as currently measured during PTCA is related to diameter stenosis but not to lesion length (2) reductions in pressure gradient and diameter stenosis are nonlinearly related.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise radionuclide angiography and thallium scintigraphy in anomalous coronary anatomy.

We report a variation of coronary anatomy heretofore undescribed. In addition, exercise radionuclide angiography and thallium scintigraphy provided functional data that complemented cardiac catheterization and aided in treatment decisions.

Left main coronary thrombolysis.

A patient with acute occlusion of the left main coronary artery in whom streptokinase thrombolysis was successful in reestablishing antegrade flow is reported. A discussion of factors influencing survival and a review of the literature is presented.

Left atrial myxoma: phonocardiographic, echocardiographic, and micromanometric hemodynamic correlations.

We used simultaneous echocardiography, phonocardiography, and high-fidelity micromanometry to investigate the impact of the movement of a large pedunculated left atrial myxoma on hemodynamics. The case we have described shows that (1) the early diastolic sound (tumor plop) coincided with maximal excursion of the tumor in the left ventricular inflow tract, (2) tumor movements during mid to late diastole corresponded to low-frequency oscillations in left ventricular pressure, (3) tumor expulsion from the left ventricle into the left atrium was initiated during "isovolumic" contraction but continued into the early ejection phase, (4) mitral valve closure was abnormally delayed until after the onset of aortic ejection, and (5) systolic ejection was initiated before coaptation of the mitral valve leaflets. These findings support the theory that tumor motion contributes to both systolic and diastolic vibrations of the entire cardiohemic system.

Avian pox infection in a Canada goose (Branta canadensis).

Lesions suggestive of Avian Pox were found on a debilitated Canada goose (Branta canadensis). These were demonstrated histologically to be characteristic poxvirus lesions and poxvirus particles were seen using electron microscopy. The virus was successfully transmitted to domestic geese but not to leghorn chickens or to domestic ducks.

Herpesvirus-like infection in a painted turtle (Chrysemys picta).

A painted turtle (Chrysemys picta) which died in captivity had marked necrosis in the liver and lungs with numerous intranuclear inclusion bodies in hepatocytes and respiratory epithelial cells. Electron microscopy revealed herpesvirus-like particles in cells in affected tissues.

Purification of DNP specific antibodies using sepharose bound DNP-para-aminobenzoylglutamate.

An immunoabsorbent column employing a DNP derivative having restricted molecular freedom (dinitrophenylated-para-aminobenzoylglutamate--Sepharose 4B) was prepared in order to isolate and purify DNP specific antibodies in high yield. The antibodies were recovered from the immunoabsorbent column in yields from 80 to 90% using 3 M sodium thiocyanate, and these antibodies retained their immunologic activity. There appeared to be limited selection of antibodies with specific affinities as was noted in a parallel experiment comparing a second antibody purification procedure.