Initial Observations on Thiamine Hydrochloride Treatment of Eggs of Landlocked Fall Chinook Salmon
M. E. Barnes, M.H. Zehfus, J.A. Schumacher,
K.S. Stock, F. Farrokhi, R.L. Nutter-2001
North American Journal of Aquaculture, 63(4): 338-342
Abstract:
Eggs of landlocked fall chinook salmon Oncorhynchus
tshawytscha from Lake Oahe, South Dakota, were treated with
standing-bath thiamine hydrochloride at 250 and 1,000 mg/L beginning at
water hardening (1 h) and continuing during transport (4 h). Biologically
insignificant increases (1–2%) in embryo survival from eyed egg to hatch
were observed for both of the thiamine treatment concentrations compared
with nontreated controls, but no differences were observed in percent
survival to the eyed stage, hatch, swim-up, or 28 d after swim-up. Egg
thiamine concentrations ranged from 2.85 to 16.14 nmol/g of wet tissue in
the control eggs. These results were probably influenced by unanticipated
dietary shifts of adult salmon during an unusual year of very low
availability of rainbow smelt Osmerus mordax. Neither thiamine
hydrochloride treatment significantly elevated egg thiamine concentrations,
but the detection of relatively small amounts of thiamine uptake was
probably hindered by measurement variation. Thiamine hydrochloride
treatments for 5 h did not increase egg mortality and allowed hatchery
personnel at remote spawning facilities to use alternative egg handling
methods after water-hardening thiamine hydrochloride treatments.
(South Dakota Department of Game, Fish, and Parks,
McNenny State Fish Hatchery, Rural Route 1, Box 205, Spearfish, South Dakota
57783-8905, USA)