RESUMO
Copper deficiency (CuD) is a common mineral disorder in ruminants, which causes histomorphological changes in the heart due to disturbances in copper-dependent metalloenzymes. However, alterations in the measurable cardiac parameters during CuD have not been studied in ruminants, especially in goats. Therefore, the current study aimed to investigate longitudinally the potential role of electrocardiography (ECG) and echocardiography to detect the CuD-induced cardiac damage at different time intervals and concomitantly highlighting the impact of CuD on specific hemato-biochemical parameters and histological cardiac disruption in goats. Eight Shiba goats were included and divided into two equal groups; copper adequate (CuA) as a control and copper-deficient (CuD) that supplemented with copper-chelating agents (sulfur 3 g/kg DM and molybdenum 40 mg/kg DM). The hemato-biochemical analysis, ECG assessment at the base apex lead, and right-side echocardiography were performed just before the experimental onset (T0), and later on at two-time intervals after existing of CuD, at the fifth (T5) and seventh (T7) months. Necropsy and histopathological examination of the heart were performed at the end of the experiment. In the CuD group, the heart dimensions at T5 and T7 showed significant increase in QRS duration, ST-segment duration, the left atrial area in systole, left ventricular diameter and volume in diastole, stroke volume, and cardiac output compared with CuA (P < 0.05). Also, myocardial degeneration, necrosis, and fibrosis were evidenced with a concurrent increase of plasma creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and cardiac troponin I (P < 0.05). In conclusion, CuD disturbs hemato-biochemical parameters and results in myocardial damage and cardiac dilatation that increases some ECG and echocardiographic parameters without development of systolic dysfunction. The ECG and echocardiography can potentially detect cardiac changes in long-lasting CuD in goats.