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<br />proportions of polymorphic loci, or average number of alleles per locus. We performed Z-statistics or tests
<br />of the normal deviate and Chi-square goodness-of-fit tests, as appropriate, independently of BIOSYS-1
<br />using methods described in Merrell (1975).
<br />Biochemical Genetic Analyses. - Our analyses of findings of altozyma variability in Colorado
<br />pikeminnow population samples will be presented pursuant to five major areas of interest: 1) allelic
<br />variability in wild adult Colorado pikeminnow populations; 2) allelic variability in juvenile Colorado
<br />pikeminnow; 3) allelic variability in YOY Colorado pikerninnow populations; 4) allelic variability in
<br />captive hatchery Colorado pikeminnow populations; 5) genetic management implications in development of
<br />hatchery broodfish populations and use of hatchery fish for augmenting natural populations; and 6)
<br />implications of allele frequency estimates in wild and captive Colorado pikeminnow populations for genetic
<br />' management.
<br />Colorado pikeminnow - 745 individuals: 169 wild adults; 39 juveniles; 478 young-of-year
<br />individuals (including 52 young-of-year reported by Ammerman and Morizot (1989)); and 59 hatchery-
<br />reared individuals were examined using starch gel protein electrophoresis. Expression of locus products
<br />from different tissues is presented in Table 2.
<br />From 89 locus products resolved from various tissues, 10 loci were found to be polymorphic in at
<br />least one sample (Tables 3, 4, 5, 6, and 7).
<br />Additionally, because not all tissues were available for study, some locus products were not
<br />available for analyses. Six loci, of a potential 15, yielded data which are summarized for hatchery
<br />populations below. Complete data were collected for 22 alleles at 9 polymorphic loci: ES-2, 3 alleles; GR,
<br />2 alleles; GPI-1, 2 alleles; GPI-2, 4 alleles; PEPS, 2 alleles; PEPB, 2 alleles; TPI-1, 2 alleles; TPI-2, 3
<br />alleles; and PG"-2, 2 alleles. Three additional loci, GP, PEPB, and PGAM-2, were
<br />discovered to be polymorphic in Colorado pikeminnow in this study, and two new alleles, GPI-2*c and
<br />TPI-2*a, were detected. While MDH--2 was reported to be polymorphic in the study of Ammerman and
<br />Morizot (1989), variability could not be resolved for this enzyme in the present study, possibly because
<br />resolution is highly dependent on use of a particular starch lot. No polymorphic loci were determined to be
<br />sex-linked (unreported data from Dexter NFH&TC broodfish), thus, all could be considered to be reflective
<br />of the full Colorado pikeminnow genome.
<br />Our use of minimally invasive tissues (skeletal muscle plugs, fin clips, and blood) allowed us to
<br />examine 12 loci and 22 alleles in 215 adults and juveniles and include data in this report that otherwise
<br />would have been lost to genetic analyses. While seemingly small in scope, the results of tissue
<br />examinations of necropsied individuals led to our ability to genetically characterize adult and juvenile wild
<br />fish and hatchery broodfish with minimal loss of vigor.
<br />The allozyme data set used for the present study comprises results for 12 loci scored in most or all
<br />individuals in each population sample: TPI-1, ACP-1, MEp, and PGAM-1 were monomorphic, while the
<br />remaining 8 loci (ES-2, GR, GPI-1, GPI-2, PEPS, PEPB, TPI-2, and PGAM-2) were polymorphic in at
<br />least one population.
<br />A1162yme variability in wild adults.- We present allele frequency estimates at polymorphic loci in
<br />putatively spawning adults from the Colorado River, Green River, San Juan River, and the Yampa River in
<br />Table 3. Only five of nine polymorphic loci exhibited variability in the spawning adults, with the proportion
<br />of total alleles ranging from a high of 15 of 22 identified alleles in the Colorado River samples to only 11 of
<br />22 in the San Juan River samples. No significant differences (Z-statistics) in allele frequencies were
<br />observed among the four samples, and uncommon alleles were shared by Colorado River and Yampa River
<br />samples (GPI-2*a) and by Colorado River and Green river samples (GPI-2*a). Significant (P<0.01)
<br />deviations from Hardy-Weinberg equilibrium expectations were observed at GPI-1 and PGAM-1 in
<br />Colorado River samples and at GPI-2 in Green River samples. Such deviations possibly indicate previous
<br />I genetic differentiation with more recent admixture. However, the mean F. value of 0.019 among all wild
<br />adults sampled suggests minimal genetic differentiation among river systems (Wright 1978)
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