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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' with 300 to 500 IU with injections every third to fifth day. *lales that were
dry at the first injections were brought to fluidity with injections of 300 IUs
daily for three or four days. The response of the females that was held in
tanks for a period of 14 days before injections wereinitiatedgave a very poor
response. The females would give a few eggs daily but all were nonviable.
It appeared that the reabsorbtion process had started. The female that re-
ceived 800 IU for three every other day injections had strippable eggs 24
hours after the third injection. The eggs that were stripped and fertilized
from this female gave strong evidence that this dosage was too strong. Over
half of the eggs wer immature and would not even water harden. About 10% of
the eggs appeared to be viable after water hardening. The remainder were
eggs that appeared to be overripe, This female yielded 139,000 eggs. The
eggs were one of•the lots that were placed in jars for hatcing. Premature
hatching made fry enumeration and hatching success impossible.
Female 4~1 that injections started with five days after arrival and in-
jected every other day with 500 IU yielded 9,000 eggs the day following second
injection. All eggs water hardened. These eggs were not coated with clay but
was placed in a :ScDonald jar and allowed to stick to the jar and were incubated.
A total of 1,800 fry were hatched from this lot of eggs. A~ eggs that lost
their adherence were prematurely hatched. The eggs appeared to loose much of
their adherence at about twoof a e. Injections continued with this
female and from 1,000 to 5,000 eggs could be stripped but all eggs were non-
viable.
Female ~~2 was injected with 300 IU every other day and the day after the
third injection had ovulated eggs that were stripped and water hardened. This
female yielded a total of 32,300 eggs. These eggs all water hardened correctly
but less than 10% (9.9) started embryo development. These eggs were incubated
on screens in tanks with a water flow over the eggs. Fungus problems and
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