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Water temperature is the major ecophysiological factor for fish survival in nature and aquaculture. Compared with many homeotherms, fish can survive prolonged periods under the condition of low temperature. However, the metabolic strategies of the liver under a cold environment are still unknown in this species. In our present study, adult zebrafish were exposed to a cold or cold plus starvation environment to analyse the morphological characteristics of hepatocytes by light microscopy and transmission electron microscopy (TEM). The fish livers were dissected and observed under a microscope, and the liver size and shape appeared normal in all groups. Periodic acid-Schiff and TEM analysis showed that hepatic glycogen was significantly lower in zebrafish exposed to cold acclimation (CF group) than that zebrafish at the control water temperature (CT group). Moreover, qPCR and IHC results indicated that the expression of PYGL (a key enzyme involved in glycogenolysis) markedly increased in the CF group. After cold plus starvation treatment (CS group), autophagy activity was significantly enhanced and numerous mitophagic vacuoles were present in the cytoplasm of hepatocytes. In conclusion, hepatic glycogen was first mobilizing to supply energy, and then autophagy, especially mitophagy, played vital roles during nutrient deprivation in fish species.

A number of previous studies use auditor propensity to issue a going concern opinion (GCO) as a proxy of audit quality when examining a sample of financially distressed firms. This study examines whether audit quality (measured by discretionary accruals) influences the probability of financially distressed firms receiving GCOs using a non‐specific sample of 2937 firm‐year observations from Australia over the period 2011–2015. The study first investigates the association between financially distressed firms and the issuance of GCOs. This association is then re‐tested after separating the total sample into low and high audit quality subsamples. The results indicate that financially distressed firms are more likely to receive GCOs, confirming the application of ASA 570 Going Concern. However, financially distressed firms that receive GCOs from their auditors are limited to firms that have higher‐quality audits.