Observations on body proportions and egg production in the female parasitic copepod ( Salmincola salmoneus ) from the gills of Atlantic salmon ( Salmo salar ) kelts exposed to different temperatures and photoperiods

• Published in: Canadian Journal of Zoology
• Main Authors: Johnston, C. E., Dykeman, D.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1987
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1139/z87-062; http://www.nrcresearchpress.com/doi/pdf/10.1139/z87-062

A total of 651 adult female Salmincola salmoneus were removed from the gills of Atlantic salmon kelts exposed to four temperature and photoperiod regimes. A comparative analysis of body proportions and egg production was undertaken on copepod samples. Mean trunk lengths were significantly different between regimes, but trunk widths were only significantly different between low temperature and 12 °C regimes. Mean egg sac lengths, widths, egg numbers, and egg diameters were significantly different between low temperature and 12 °C regimes, but not between 12 °C regimes with different photoperiods. Photoperiod may have had an effect on trunk length, but not on any other morphometric measurements. Cool water temperatures significantly reduced body size and numbers of eggs and this may account for some of the differences in body proportions observed by other investigators.