Response to Hyperthermia and Hypoxia Stress during Compensatory Growth in Penaeus vannamei

Abstract

This study evaluated oxidative stress and resistance to abiotic stress factors of juvenile Penaeus vannamei during compensatory growth. Shrimp underwent two dietary treatments in a 50-day experiment: a reference group (REF) fed ad libitum and a restricted group (T50) fed 50% of the REF diet for 10 days, followed by 40 days of ad libitum refeeding. During refeeding, shrimp from both groups were exposed to two abiotic challenges: 1) hyperthermia (34°C) for 12 hours and 2) hypoxia (1.5 mgO2 L-1) for 9 hours, followed by reoxygenation for 3 hours (5 mgO2 L-1). Compensatory growth in the T50 group was evidenced by increased specific growth rate, hyperphagia, and improved feed efficiency. Moreover, the malondialdehyde content (MDA) and catalase activity in the shrimp hepatopancreas increased during compensatory growth, indicating oxidative stress. This result converges with the increased metabolism assessed by metabolic chambers. While hyperthermia caused oxidative stress, as indicated by the increase in MDA content in both groups, shrimp under compensatory growth demonstrated similar resistance to the REF group. Exposition to hypoxia and reoxygenation did not generate significant oxidative stress. Compensatory growth induced oxidative stress in P. vannamei without compromising resistance to hyperthermia or hypoxia events.