Combined effects of elevated rearing temperature and dietary energy level on heart morphology and growth performance of Tasmanian Atlantic salmon ( Salmo salar L.)

• Published in: Journal of Fish Diseases
• Main Authors: Foddai, M, Carter, CG, Hilder, PE, Gurr, H, Ruff, N
• Format: Article in Journal/Newspaper
• Language: English
• Published: Blackwell Publishing Ltd 2022
• Subjects: Agricultural; Veterinary and Food Sciences; Fisheries sciences; Aquaculture and fisheries stock assessment; Atlantic salmon; Salmo salar
• Online Access: https://doi.org/10.1111/jfd.13555; http://www.ncbi.nlm.nih.gov/pubmed/34787904; http://ecite.utas.edu.au/148961

Cardiac abnormalities may pose a threat to salmonid aquaculture due to their potential detrimental effect on fish health and welfare. The teleost heart is an extremely plastic organ with important morphological differences between wild and farmed fish that include ventricular shape, alignment of the bulbus arteriosus and epicardial fat deposition. However, little is known about how different factors and interactions among them may affect cardiac morphology of Atlantic salmon. To determine whether rearing temperature could induce cardiac malformations in large Tasmanian Atlantic salmon, we examined a range of cardiac morphology indicators and growth parameters in a population of 12kg seawater salmon ( n =60 temperature −1 diet −1 ) exposed to control and elevated temperatures of 15 and 19C, respectively, while fed one of two commercial feeds with different dietary energy levels. Most fish possessed conspicuous fat around the heart with a tendency towards a rounded ventricle and a more obtuse angle of the bulbus arteriosus. However, fish showed no significant differences in heart shape and bulbus alignment in relation to water temperature and dietary energy. These results suggest that cardiac morphology of large Atlantic salmon is unlikely to be affected by rearing temperature and dietary energy during the grow-out phase.