7145 ‎(2)‎

• UCREFRP Catalog Number: 7145
• Author: Inslee, T. D.
• Title: Spawning of Razorback Suckers
• USFW Year: 1981.
• Copyright Material: NO

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tank at this time. The following morning there were many eggs in the tank
and the female was still flowing eggs. She was hand stripped, the eggs
fertilized and the eggs scattered on the rocks in the tank after the males
were removed. The 24 inch standpipe was replaced by one six inches long and
four air stones were added to the tank. It was estimated that well over 50%
of the eggs incubating in the tank had been hand stripped. Previous sample
counts and observations of the eggs released by the female in the tank gave
indications that less than 50% water hardened correctly and Iess than 10%
of the eggs were developing embryos. A sample of the eggs that were hand
stripped were held for observation and 81% had water hardened. H ~ '^^ ~""'-~
st d b early t th day.
i
Fry were caught in a small tank from the drain of the circular tank.
Fry started swimming out of the circular tank on the 14th day after spawning.
A total of 11,000 fry was obtained from the spawning of this female.
Holding House Tank Spawning
There was no eggs deposited on rocks in any of the tests utilizing
holding house tanks for spawnings. Some of the females had ovulated eggs
that were lost when fish were handled for reinjections. There was little
or no indication of nest building activity in any of the tanks. This tech
nique is not recommended for retrial in future years. The females that re~
ceived 800 IU chorionic gonadotrapin had ovulated all the eggs in her over;
by the morning after the third treatment but no eggs were deposited on the
bed of rocks. This female was stripped and eggs placed in a jar .for hatch
Horu:one Tnjections
Hormone injections of chorionic gonadotropin that~was administered to
females and males held in tank in some cases caused the expected reaction
in other cases no response was evident. Males fluidity could be maintains
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