Evaluation of ST-Segment Duration and Morphology of Standard Base Apex Lead Electrocardiograms in Different Age Groups of Apparently Healthy Holstein Cattle

The present study was conducted to obtain electrocardiographic data regarding the values of ST-segment morphology and duration from 84 apparently healthy Holstein cattle in fourteen different age groups from newborn to 7 years old. We recorded electrocardiograms in standard base apex lead system with the paper speed 25 mm/sec. and calibration of 10 mm equal to 1 mV. The morphologic assessments of electrocardiograms showed that all groups had normal isoelectric ST-segment, except newborns. Elevation of ST-segment was detected in 64.2% of newborn calves. The magnitude of this up sloping was 0.10±0.03 mV. The results of the comparison of ST-segment duration among different age groups showed that there were significant differences between the ST-segment duration of newborns (0.11±0.02, sec) and 5 years old (0.16±0.03, sec.), and also between 15 days (0.09±0.03, sec.) and 5 years old (P<0.05). The results of the present study may be accepted as normal ST-segment duration and morphology in different age groups of healthy Holstein cattle which will provide a good basis for judging and interpreting electrocardiograms. Key Words: Electrocardiography, ST-segment, morphology, Holstein cattle OZET FARKLI YAŞ GRUPLARINDA SAĞLIKLI OLARAK GOZLENEN SIYAH ALACA SIĞIRLARDA BASE APEKS DERIVASYONUNDAKI STANDART ELEKTROKARDIYOGRAMDA ST SEGMENT ARALIĞININ VE MORFOLOJISININ DEĞERLENDIRILMESI Bu calismada yeni dogandan 7 yasina kadar 14 farkli yas grubunda bulunan 84 adet saglikli Siyah Alaca sigirda ST segment morfolojisi degerlerine ait elektrokardiyografik verilerin elde edilmesi amaclanmistir. Elektrokardiyogramlar standart base apeks derivasyon sisteminde, 25mm/sn kagit hizinda ve 1mV'ye esit 10mm kalibrasyonda kayit edilmistir. Elektrokardiyogramlarin morfolojik degerlendirilmesi sonucunda yeni doganlar haricinde tum gruplarin normal izoelektrik ST segmentine sahip olduklari gozlenmistir. Yeni doganlarin %64,2'sinde ST segmentinde yukselme tespit edilmistir. Bu yukselme miktarinin egimi 0,10±0,03 mV olarak saptanmistir. ST segment araliginin farkli yas gruplari arasinda karsilastirilmasi sonucu; yeni doganlar (0,11±0,02 sn) ile 5 yasindakiler (0,16±0,03 sn) ve 15 gunluk (0,09±0,03 sn) ile 5 yasindakiler arasinda onemli bir farklilik belirlenmistir (P<0,05). Bu calismanin sonuclari, farkli yas gruplarindaki saglikli Siyah Alaca sigirlarda ST segment araligi ve morfolojisi normal olarak kabul edilerek, elektrokardiyogramlarin degerlendirilmesi ve yorumlanmasinda iyi bir kaynak olusturacaktir. Anahtar Kelimeler: Elektrokardiyografi, ST-segment, morfoloji, Siyah Alaca sigir