Atrioventricular Dissociation and Congestive Heart Failure in a Ring-Necked Pheasant ( Phasianus colchicus )

Radiographic Reference Intervals of the Cardiac Silhouette Width in the Bald Eagle (Haliaeetus leucocephalus)

Radiograph imaging is an important diagnostic tool for assessing cardiac size in avian patients. The bald eagle (Haliaeetus leucocephalis), once on the United States Federal List of Endangered and Threatened Wildlife and Plants, is now a thriving species in the United States. However, there is surprisingly little information regarding bald eagle cardiac reference values obtained through radiographic imaging for use in assessment of cardiac disease in this species. This study was performed to establish reference values of cardiac size in the bald eagle. Ventrodorsal radiographic images were taken from 9 healthy birds obtained from a raptor rehabilitation facility. Cardiac silhouette width to thorax width, cardiac silhouette width to sternum width, cardiac silhouette width to hepatic silhouette width, and cardiac silhouette width to coracoid width were obtained. Ratios were calculated between the respective areas measured. The results showed that the cardiac silhouette averages 44%-52% of the thoracic width, 71%-86% of the sternal width, 94%-117% of the width of the hepatic silhouette, and 500%-920% of the coracoid width. In the individuals studied there was a strong correlation between cardiac silhouette width to thoracic and sternal width whereas cardiac width with hepatic and coracoid widths had a moderate to weak correlation respectively. The values obtained in this study can be used to radiographically assess the cardiac size of bald eagles, thus aiding in the diagnosis of cardiomegaly in this species.

ELECTROCARDIOGRAM ANALYSIS OF THE GOLDEN ( CHRYSOLOPHUS PICTUS) AND SILVER ( LOPHURA NYCTHEMERA) PHEASANTS

The aim of this study was to describe normal electrocardiogram patterns and values in two species of conscious pheasants (golden and silver). The standard bipolar and augmented unipolar limb leads electrocardiograms were recorded in the birds. The wave forms were analyzed in all leads at 50 mm/sec and at 10 mm = 1 mV to determine PR, QRS, ST, and QT durations and P, net QRS complex, and T amplitudes. The polarity of each wave form was tabulated in all leads. The mean electrical axis for the frontal plane, calculated using leads II and III, was mostly negative in two species (-43 ± 28.0° in golden and -92 ± 10.0° in silver pheasant). The P wave was predominantly positive in most of the leads. The pattern of wave forms of the QRS complexes were different (Rs, QS, rS, R, RS, QR, qR). The T wave was almost positive in leads I, II, III, and aVF. The heart rates of the birds were mean (± SD) of 320 ± 36 beats/min (golden) and 314 ± 31 beats/min (silver). Description of normal electrocardiogram parameters will facilitate a better understanding of electrocardiogram changes of unhealthy birds.