Electrocardiographic Studies in Different Age Groups of Nellore Cross-Breed Sheep

Abstract

Aim: Present study was aimed to record the electrocardiography indices in different age groups of clinically healthy Nellore cross-breed sheep.Background: Normal electrocardiographic studies of different species of animals help in detection of cardiac abnormalities and helpful while monitoring the vital parameters during the diseased conditions, treatment trails and operative procedures. Variations in the parameters were recorded in small ruminants based on the breed. Information pertaining to the electrocardiographic findings of Nellore cross-breed sheep was not documented. Methodology:The present study was conducted at College of Veterinary Science, Proddatur, YSR Kadapa District of Andhra Pradesh, India from 2013 to 2016. Apparently, healthy local Nellore cross-breed of sheep were categorized into five groups based on their age and in each group twenty sheep were included. The animals were examined prior to ECG recording and were proved to be clinically healthy. The electrocardiography was recorded on a bipolar base apex lead system. Duration and amplitude of the P, QRS complex and T wave and the PR, QT intervals and heart rate were measured and averaged from successive beats in lead I. Results:Heart rate was 73.2±1.62 in adults and it was 115.8±2.76 in kids. The mean amplitude of P wave was 0.169±0.005 mV in lambs and 0.177±0.005 mV in the adult group. Mean duration of P wave, QRS complex and T wave was 0.044±0.003 sec, 0.066±0.003 sec, 0.103±0.003 sec in adult group and it was 0.041±0.006 sec, 0.063±0.003 sec and 0.104±0.004 sec in kids. Conclusion:No significant difference was found in P wave amplitude, duration of P wave, QRS complex and T wave. The heart rate, an amplitude of ECG waves including QRS complex, T wave and duration of P-R, Q-T and R-R intervals showed the significant difference between the age groups. Heart rate was gradually decreased while aging and the negative correlation between age of the sheep and heart rate was noticed. This study provides information on the cardiac rhythm, heart rate, duration, and amplitude of ECG deflections in one of the common sheep breed in the YSR District of Andhra Pradesh.Keywords: Sheep; Electrocardiography; Heart rate; Nellore brown Materials and MethodsThe present study was conducted at Department of Veterinary Clinical Complex, College of Veterinary Science, Proddatur, Andhra Pradesh from 2013 to 2016. Apparently healthy local cross-breed of sheep (Nellore) were categorized into five groups based on their age and in each group twenty sheep were included. Sheep were categorized into Group-I (below six months), Group-II (six months to one year), Group-III (one year to two years), Group-IV (two years to three years) and Group-V (above three years). The animals were examined prior to ECG recording and were proved to be clinically healthy. The electrocardiography was recorded on a bipolar base apex lead according to the standard and previous studies [5]. Electrocardiography recording was done in a quiet standing position by using the alligator type e...