Heart rate variability indices in the time domain in healthy dogs supplemented with omega n-3

The analysis of heart rate variability (HRV) in the time domain was performed by dynamic electrocardiographic monitoring for twenty-four hours (Holter method) in ten male and ten female healthy mixed-breed dogs before and after four weeks of oral supplementation with long-chain polyunsaturated fatty acids (PUFAs) derived from omega n-3 [497 mg docosahexaenoic acid (DHA) and 780 mg eicosapentaenoic acid (EPA)]. Males received an average dose of 34.9 mg DHA/kg and 22.2 mg EPA/kg, whereas females received an average of 27 mg DHA/kg and 43 mg EPA/kg. HRV indices calculated in the time domain were the following: NN, SDNN, SDANN, SDNN index, pNN50, rMSSD and heart rate, taking into account the effects of gender and supplementation. The results showed no significant effects of supplementation or gender on the indices; thus, dietary supplementation with omega PUFAs derived from n-3 over four weeks did not decrease heart rate and did not increase heart rate variability in healthy dogs.