Effects of the level of copper supplementation in diet on electrocardiogram of Japanese quails (Coturnix coturnix japonica)

The aim of this study was to assess the effects of various levels of copper supplementation on electrocardiogram (ECG) of Japanese quails (Coturnix coturnix japonica). For that purpose, 75 chicks (one-day-old) were divided into four groups and they received 0 (Group I), 100 (Group II), 250 (Group III) and 500 (Group IV) mg/kg copper in addition to their concentrate for 6 weeks. Each group were subdivided into females and males. Fresh water and feed was offered ad libitum and all ECGs were standardized at 1 mV = 20 mm, with chart speed of 50 mm / s. Leads I, II, III, aVR, aVL and aVF were determined. Heart rate was not different between the groups (P > 0.05) but it was insignificantly lower in females (range 464-513 beats/min) than in males (range 504-521 beats/min). Mean electrical axis, calculated from leads II and III, did not differ between the groups and it was between -76 degrees and -89 degrees in females, and between -83 degrees and -91 degrees in males. Waves in lead I had the lowest amplitudes and they were isoelectrical. P wave was detected only in some of the leads (III, aVR, aVL) and it was generally fused into the T wave. T wave was negative in aVR and aVL leads whereas it was positive in leads I, II, III, aVF. Q wave was, however, observed only in aVL lead. QRS complex was in the form of QS or rS. There were no differences between the groups or sexes in amplitude and duration of QRS complex and in duration of T (P-T), P-Q or Q-T. In conclusion, it was observed that Japanese quail chicks are able to tolarate, in terms of ECG findings, diets containing copper at a level as high as 500 ppm.