Influence of lipid removal on stable isotope analysis of soft tissues of jumbo flying squid Dosidicus gigas off equatorial waters
LIU Na1, LIU Bilin1,2,3,4*
1.College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; 2.National Engineering Research Center for Oceanic Fisheries, Shanghai 201306, China; 3.Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China; 4.Key Laboratory of Oceanic Fisheries Exploration, Ministry of Agriculture and Rural Affairs, Shanghai 201306, China
Abstract: In order to explore the influence of lipid removal on carbon and nitrogen stable isotopes of jumbo flying squid Dosidicusgigas with mantle length of 195-324 cm and the difference in stable isotopes between different soft tissues, stable isotopes in muscle, gonad and digestive gland treated by degrease and non degrease were analyzed and compared. The results showed that there were significantly different δ13C and C/N values in the three soft tissues before and after lipid removal (P<0.05), and the δ15 N significantly different in the muscle and gonad before and after lipid removal (P<0.05), without significantly different δ15 N in the digestive gland before and after lipid removal (P>0.05). The δ13C, δ15 N and C/N were shown to be significant differences among the three tissues before and after lipid removal (P<0.05). The comparison revealed that the descending order of contents of stable isotopes in different tissues was described as: δ13Cbefore and δ13Cafter: muscle> digestive gland>gonad, δ15Nbefore and δ15 Nafter: muscle>digestive gland> gonad; C/Nbefore: gonad>digestive gland>muscle, C/Nafter: digestive gland >gonad>muscle. The findings indicated that lipid had significantly influence on the stable isotope analysis of soft tissues. It is suggested that lipid in soft tissues be removed before using stable isotopes to study trophic ecology.
2021, Vol. 36 
