A Study of Electrocardiographic Patterns in a Population of Commercial Broiler Chickens

Abstract

A study was completed to characterize the electrocardiographic (ECG) patterns of male broiler chickens. Data were collected from 300 commercial broilers. ECG readings were collected from all birds between 12 and 15 days of age and then twice more at 10-day intervals. The measurements. included heart rate and rhythm, QRS complex duration, amplitude and mean electrical axis (MEA), incidence of ascites and incidence of sudden death syndrome (SDS). Eight birds died from SDS and 4 birds died from ascites. Twelve birds were condemned for ascites at the processing plant. The overall population heart rate declined with age. Birds that died of SDS had a higher heart rate, whereas those that developed ascites had a lower heart rate than the remainder of the population. The normal MEA was found to be between 0 degree and 180 degrees. On average 30% of birds showed left or right QRS axis deviation, and this pattern was observed in 14 of the 16 birds that developed ascites. Several types of cardiac arrhythmias were observed, the most common being premature ventricular contractions (PVC). The incidence of PVC increased with age, ranging from 1% at 12-15 days of age to 8.9% at 32-35 days of age. QRS axis deviation was present in 5 SDS birds. It is concluded that some 30% of the broiler flock tested was at risk of developing heart failure or heart-related disease.

Electrocardiogram Reference Values for the Buzzard in Spain

“…Five patients showed overlapping of the P wave and the preceding T wave and they were excluded from our study because this PT form made ac-curate measurements impossible (Zenoble, 1981). In a previous report fused T and P deflections were seen in 88% of the birds that developed ascites (Olkowski et al, 1997). However, the role of this PT fused pattern in the pathogenesis of ascites and sudden death syndrome warrants more detailed investigation.…”

“…In ducks, the electrocardiographic alterations associated with hyperkalemia included bradycardia and tall T waves (Andersen, 1975). In recent years, electrocardiography has been used to investigate the sudden death syndrome and ascites in broilers (Odom et al, 1992;Olkowski et al, 1997). Electrocardiography may be used also to monitor heart rate and rhythm in an anesthetized patient (Degernes et al, 1988).…”

Ascites Syndrome in Broiler Chickens - A Physiological Syndrome Affected by Red Blood Cell

“…Of most importance has been the finding that increased S-wave amplitude in standard limb lead II indicates increased susceptibility to AS [111]. However, there were no ECG readings indicative of primary pulmonary hypertension in most birds that developed ascites [165]. A slower heart rate (bradycardia) [55,116], as well as reduction in the pulse rate had been found in birds developing AS [55] and in acutely cold-exposed birds [116].…”

Ascites in poultry: Recent investigations

“…The most common abnormality described was an increase in S-wave amplitude in leads II and III, and a ventricular ® brillation (VF) that correlated with the degree of right ventricular hypertrophy (Odom et al, 1989Wideman & Kirby, 1995a,b, 1996. While the normal mean electrical axis of the commercial broiler lies between 0 and 180 o (Olkowski et al, 1997), the axis rotates from 1 3°to 2 88°during ascites development . These observations of right-axis deviation are similar to those observed with vitamin E de® ciency in adult birds (Sturkie et al, 1954).…”