Determination the Normal Parameters (amplitude and duration) of Electrocardiogram Waves in River Buffaloes (Bubalus Bubalis) of Khuzestan

An easy way to evaluate the cardiovascular system is recording the cardiac electrical activities. Reviewing the available literatures suggests that buffalos ECG compared to other large animals have been neglected and the carried out studies in this field are too limited. Using this method for the diagnosis of cardiac disorders needs the standardization, not only among animal species but also among different breeds of a species. The present study was performed to determine the normal parameters of electrocardiogram in 100 clinically healthy buffaloes of different ages and sexes. The buffaloes were divided into male and female and two age groups (less than 2.5, and more than 2.5 yrs.) on the base of dental formula. After taking the anamnesis and performing a clinical examination, electrocardiogram was obtained based on base - apex lead system with the paper speed of 25mm sec-1 and sensitivity of 10 mm mV-1 at rest. Results showed that regardless of age and sex, the median and interquartile range of P, R, S and T waves' amplitude (voltage) was, 0.18±0.04, 0.69±0.40, 0. 97± 0.31 and 0.20 ±0.25 mV, respectively and the duration of p wave, QRS complex, and T wave was determined 0.06 ±0.01, 0.06 ±0.01 and 0.08 ± 0.02 seconds, respectively. Only in a less than 2.5 years old female buffalo, Q wave was recorded, the amplitude of this wave was 0.07 mV. Statistical method showed that among different ECG parameters, there was significant difference between the two sexes (p< 0.05), only in amplitude of S wave. Also there were significant differencesbetween two age groups in all of the electrocardiogram parameters with the exception of P and R amplitude (p