CHANGES OF HEART RATE AND RHYTHM IN HARBOR SEAL PUPS DURING REHABILITATION

• Main Authors: Fonfara, Sonja, Sundermeyer, Janne, Casamian Sorrosal, Domingo, Rosenberger, Tanja
• Format: Conference Object
• Language: English
• Published: 2014
• Subjects: harbor seal; harbour seal
• Online Access: http://hdl.handle.net/1983/685683fe-706c-420c-88a3-f20103a82607; https://research-information.bris.ac.uk/en/publications/685683fe-706c-420c-88a3-f20103a82607

The autonomic nervous system of harbor seal pups matures during their first months of live, which is relevant for the seals’ foraging capacity. Electrocardiographic (ECG) recordings during this crucial period have not been performed previously in orphaned seal pups recovering in seal centres. ECGs of 1 minute were recorded from 50 harbour seal pups rehabilitated in a seal centre at admission, after 2 weeks and prior to release back into the wild using an Iphone ECG adapter. ECGs of diagnostic quality were obtained in 92% of recordings. The predominant heart rhythm at admission was sinus tachycardia (150/min, range 110-180/min), and at discharge sinus arrhythmia (127/min, range 25-180/min), with a significant reduction of heart rate (HR) during rehabilitation (p<0.001). P-wave length and PQ distance increased (p<0.001), and QT reduced during rehabilitation (p<0.001), and a negative correlation of PQ (r = -0.439) and QT (r = -0.389) with HR was present. First and second degree atrioventricular blocks (AVB), supra- (SVPC) and ventricular premature complexes were recorded, with second degree AVB and SVPC being more frequent after 2 weeks and first degree AVB at release. The results of this study did show changes in the heart rhythm during rehabilitation, which will reflect potential diseases and exposure to stress, but also suggests maturation of the autonomic nervous system with a predominant vagal tone at discharge.