Use of electrocardiographic analysis for investigation of ascites syndrome in broiler chickens.

This study was conducted (at high altitude [1969 meters]) to determine whether chicks predisposed to cardiac failure and ascites could be identified and followed during growout with non-invasive electrocardiographic (ECG) techniques. ECG recordings were made on 40 chicks at 1 week of age. All recordings were analyzed by quantifying the amplitude in millivolts of the R-, S-, and T-waves in each of the recordings. During the study, ascites-related mortality was 40%, with the majority of the deaths occurring between 5 and 8 weeks of age. Chicks exhibiting moderate-to-severe right ventricular hypertrophy, as identified by ECG analysis at 1 week of age, were predisposed to development of ascites. Thus, the variability in ascites-related mortality observed in field cases may be directly related to the number of predisposed chicks at the time of placement in the broiler house.