This study was carried out to determine the role of electrolytes in the genesis of cardiac arrhythmias in cattle which were referred to the Animal Hospital of Veterinary College in North West of Iran. 310 sick cows were blood sampled for serum calcium, inorganic phosphorus, magnesium, chloride, sodium and potassium assessment and then from all cases ECG, were taken using a base-apex lead. The ECS findings were classified in 13 groups. The analysis of serum electrolytes showed that only significant differences in mean of serum potassium (P
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