Ảnh hưởng của hormone tăng tưởng lên ở cá chuyển gen

[kemongmo]

Biểu hiện hormone tăng trưởng ở sinh vật chuyển gen có thể đem lại những tác động tốt hơn trong lĩnh vực nuôi trồng thủy sản, ví dụ như gia tăng tốc độ tăng trưởng của coho salmon lên gấp 11 lần. Một số nhà nuôi trồng thủy sản muốn tạo ra những dòng cá và sò thương mại được chuyển gen, tuy nhiên điều này là không thuận lợi về mặt sinh thái, an toàn thực phẩm, khía cạnh quản lý cũng như là việc chăm sóc vật nuôi.

We review the impacts of GH transgene expression on the behavior and welfare of cultured fishes, focusing on Atlantic salmon, coho salmon, tilapia and common carp lines that have been posed for commercial production. Elevation of GH increases rates of protein synthesis and lipid mobilization, affecting not only growth, but also feed conversion efficiency, metabolic rate, body composition, head and body morphometrics, osmoregulation, and age at maturity, with other modifications particular to species and transgenic lines. Because of heightened feeding motivation, transgenic fishes often prove more active, aggressive, and willing to risk exposure to predation. Swimming ability of some transgenic lines is reduced. While limited in scope, studies suggest that pfish of some transgenic lines show lessened reproductive behavior. Welfare issues posed by morphological, physiological, and behavioral alternation in GH-transgenic fishes have not been well characterized. The use of weaker promoters in expression vectors and by selection of transgenic lines with physiologically appropriate levels of GH expression may reduce welfare issues that do arise. Also, markers of welfare for GH-transgenic fish under production conditions can be monitored to determine how culture systems and practices can be modified to promote fish welfare. GH-transgenic previous termfishnext term may be the first transgenic animals commercialized for food production; with other transgenic fishes likely to become widely produced, a range of behavioral and welfare issues will follow.