Open AccessGrowth Acceleration of Seawater‐Adapted Female Chinook Salmon Oncorhynchus tshawytscha by Constant Infusion of Recombinant Bovine Growth‐Hormone Under Ambient Summer Conditions
Author(s) -
Ted Down N. E.,
Schulte Patricia M.,
Donaldson Edward M.,
Dye Helen M.,
Souza Lawrence M.
Publication year - 1989
Publication title -
journal of the world aquaculture society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.655
H-Index - 60
eISSN - 1749-7345
pISSN - 0893-8849
DOI - 10.1111/j.1749-7345.1989.tb01000.x
Subject(s) - oncorhynchus , bovine somatotropin , biology , chinook wind , zoology , endocrinology , medicine , hormone , growth rate , recombinant dna , fish measurement , fishery , growth hormone , fish <actinopterygii> , biochemistry , geometry , mathematics , gene
Seawater‐adapted female chinook salmon ( Oncorhynchus tshawytscha ) in their second summer were treated with one of three doses of recombinant bovine growth‐hormone (rbGH) administered in a continuous fashion by osmotic pump for approximately five weeks. Untreated fish, sham‐treated fish and fish treated with the low dose of hormone (0.003 μg/g bwt/day) did not differ significantly in their growth performance over the 10 week course of the experiment. By the end of the treatment period (week 6) the mean increases in fork length and weight for these groups were 7.6% and 38.9%, respectively. A dose‐dependent enhancement of growth was observed for the fish treated with the mid (0.016 μg/g bwt/day) and high (0.078 μg/g bwt/day) doses of hormone. After 6 weeks, the fish given the mid dose of rbGH had gained 9.6% in fork length and 45.3% in weight, while the fish treated with the high dose of rbGH had gained 13.9% in fork length and 52.9% in weight. A significant increase in specific growth rate was observed for these latter two groups during the treatment period while condition factor declined in response to the high dose of rbGH. This experiment indicates that chronic administration of growth‐hormone to chinook salmon can result in a dose dependent elevation of growth rate. Results are discussed in relation to previous attempts to accelerate the growth of Pacific salmon with growth‐hormone and the potential for using recombinant growth‐hormone to improve the production characteristics of salmon being cultured in seawater.