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Wicks, B.J., L.A. Barker, B.J. Morrison, and W.H. Beamish, 1998. Gonadal
Variation in Great Lakes Sea Lamprey, Petromyzon marinus, Larvae,
University of Guelph.
Reprinted from Journal of Great Lakes Research
(1998) 24(4): 962-968
Gonadal Variation in Great Lakes Sea Lamprey, Petromyzon
marinus, Larvae
Abstract
The observation of atypical gonads in land-lacked sea lamprey, larvae from
several streams tributary to the Great Lakes led to this descriptive study on
typical male and female gonads, as well as atypical gonads. Typical male and
female gonads examined in the present study have similar characteristics to
those observed in the past; however, larvae with atypical gonads have some
characteristics of both male and female larvae. Many of the atypical larvae had
an unusual number of germ cells, or many atretic oocytes. Based on quantitative
evaluation of several gonadal characteristics of male, female and atypical
larvae, it was possible to verify atypical status of 88% of the larvae which had
been qualitatively assigned the atypical sex. Examination of larvae front 15
different populations suggest the proportion of atypical larvae is currently
much higher in streams tributary to the Great Lakes, than was previously
observed The slowing of gonadogenesis, or the diversion of energy for somatic
development are possible causes of the? atypical gonads observed in this study.
Entire Paper
Contact: Bill Beamish, University of Guelph,
Department of ZoologyGuelph, ON
N1G 2W1, CANADA
Keywords: Sea_lamprey, Basic_biology
Product Type: Research, Basic_biology
User Type: General
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