Effects of Tricaine Methanesulphonate (MS-222) on Physiological Stress and Fresh Quality of Sea Bass (Lateolabrax maculatus) under Simulated High-Density and Long-Distance Transport Stress

Abstract

This study aimed to evaluate the effect of different transport densities on water deterioration, physiological response, nutrients, and fresh quality of sea bass (Lateolabrax maculatus) at 30 mg/L tricaine methanesulphonate (MS-222) before and after simulated live transport. The results indicated that the addition of MS-222 could effectively decrease mortality compared with the control (CK) sample during the simulated live transport. The concentration of dissolved oxygen was lower and the total ammonia nitrogen was higher in the high transport density samples than those of low transport density samples after 72 h in transport. The level of blood cortisol (COR), glucose (GLU), lactic acid (LD), aspartate aminotransferase (AST), alanine aminotransferase (ALT) for the sea bass were significantly higher compared with the CK sample (p < 0.05) during the simulated live transport and after 12 h of recovery. These results indicated that the sea bass presented a strong stress response in high-density transport. The glycogen, fat, and protein of the sea bass were degraded to supply the energy for the body in the process of surviving the transportation, resulting in the decreased nutrient content in the muscle, which recovered to the initial level (CK) after 12 h. The increase in flavor substance content, such as free amino acids, nucleotides, organic acids, and minerals, enhanced the special flavor of the muscle during the simulated live transport. This study demonstrates that the addition of MS-222 at 30 mg/L to the transport water is an effective method for live fish to realize low mortality and physiological response during high-density and long-distance transport.

Keywords: MS-222; flavor; nutrition; stress; transport density of live fish.

Figure 1

Schematic diagram of experimental design for simulating long-distance transportation of sea bass.

Figure 2

The survival rate of sea bass in treatment samples and basal samples during and after transport. MS-1-1: 30 mg/L MS-222, fish to water ratio was 1:1; NMS-1-1; fish to water ratio was 1:1; MS-1-2: 30 mg/L MS-222, fish to water ratio was 1:2; NMS-1-2: fish to water ratio was 1:2; MS-1-3: 30 mg/L MS-222, fish to water ratio was 1:3.; NMS-1-3: fish to water ratio was 1:3.

Figure 3

The changes in total ammonia nitrogen concentration (A), dissolved oxygen concentration (B), and pH value of transport water (C) in different treatment samples during live transport. Vertical bars indicate standard deviation. Asterisk (*) represents significant differences (p < 0.05) at transporting for 0 h and after transport. Different lowercase letters represent significant differences among three treatment samples at the same time during live fish transport.