Effect of growth hormone transgenic Synechocystis on growth, feed efficiency, muscle composition, haematology and histology of turbot (Scophthalmus maximus L.).

Abstract

The present study investigated the e¡ect of supple menting feed with transgenic Synechocystis sp. PCC6803 containing the Paralichthys olivaceus growth hormone (GH) gene on growth, feed intake and feed e⁄ciency ratio, muscle composition, hae matology and histology of turbot (Scophthalmus max imus L.). At the end of the 40-day feeding trial, the speci¢c growth rate of ¢sh fed the supplemented feed with 1.0% transgenic Synechocystis sp. PCC6803 was 21.67% higher (Po0.05) than that of control ¢sh. Although body weight and feed e⁄ciency ratio sig ni¢cantly increased (Po0.05) in ¢sh fed the diet sup plemented with transgenic alga, feed intake and condition factor of the experimental ¢sh were unaf fected. Muscle composition analysis showed that the protein content was positively in£uenced by the transgenic alga, whereas the lipid content was unaf fected. Haematological parameters, including red blood cell, white blood cell, haemoglobin, and serum biochemical indices, such as enzyme activities of ala nine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, con centrations of total protein, glucose, blood urea nitrogen, creatinine, triglyceride and cholesterol and ion levels of K, Na, Cl, P were not in£uenced by supplementing the transgenic Synechocystis sp. PCC6803. Furthermore, no histopathological altera tions were induced by transgenic alga treatment in the stomach, intestine, liver, spleen and kidney of the experimental ¢sh. The results of the present study indicated that transgenic Synechocystis sp. PCC6803 containing P. olivaceus GH gene is an ef- ¢cient growth promoter and a safe feed additive for ¢sh.