Determination of frequency distribution of oocytes at different maturity phases in the ovaries of roach, Rutilus rutilus (L.)

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Factors affecting between-lake variation in the occurrence of epidermal papillomatosis in roach, Rutilus rutilus (L.).

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According to sperm competition models, a male spawning in a disfavoured role should have spermatozoa with higher velocity but shorter longevity compared with a male spawning in a favoured role. Moreover, immunosuppressive androgens are needed to produce both secondary sexual characters and sperm cells. The ‘sperm protection’ hypothesis suggests that the immunosuppressive action of androgens has...

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High prevalence of zoonotic trematodes in roach (Rutilus rutilus) in the Gulf of Finland

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ژورنال

عنوان ژورنال: Acta Ichthyologica et Piscatoria

سال: 2003

ISSN: 0137-1592,1734-1515

DOI: 10.3750/aip2003.33.1.04