SERUM TROPONIN-T CONCENTRATIONS IN 2 STRAINS OF COMMERCIAL BROILER-CHICKENS AGED ONE TO 56 DAYS

Troponin T is a specific and sensitive serological indicator of acute myocardial infarct ion in human patients. The concentration of serum t roponin T was measured by an ELISA technique in two strains of healthy commercial broiler chickens (Cobb 500 and Ross I) aged between one an d 56 days. The concentrations of cardiac-derived troponin T in day-old Cobb and Ross chicks were 5.74 and 8.35 ng ml(-1), respectively, and much higher than in 14-day-old chicks. Between 21 and 56 days, the val ues were consistently lower than the mean troponin T concentration of 0.20 ng ml(-1) reported previously in a group of healthy 30-day-old br oilers. All the other heart measurements, including the arterial press ure index, were within normal limits. The high troponin T concentratio ns after hatching are probably due to an embryonic isoform that rapidl y becomes replaced by an adult isoform by three weeks of age. The data suggest that in healthy birds, there is an inverse relationship betwe en troponin T concentrations and age.