Investigations on a disease causing serious mortalities in crayfish (Astacus leptodactylus Esch.) in Turkey
Baran, I.; Rahe, R.; Oray, I.; Soylu, E. (1989). Investigations on a disease causing serious mortalities in crayfish (Astacus leptodactylus Esch.) in Turkey, in: De Pauw, N. et al. (Ed.) Aquaculture: a biotechnology in progress: volume 1. pp. 921-927 In: De Pauw, N. et al. (1989). Aquaculture: a biotechnology in progress: volume 1. European Aquaculture Society: Bredene. ISBN 90-71625-03-6. 1-592 pp., more |
Available in | Authors | | Document type: Conference paper
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Authors | | Top | - Baran, I.
- Rahe, R.
- Oray, I.
- Soylu, E.
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Abstract | In the period 1970-1985, Astacus leptodactylus Esch. became the most important inland fisheries product of Turkey with maximum yields exceeding 5 000t exclusively for export. Early 1984, a fungal disease spread rapidly through the crayfish stocks and by fall 1986, major resources had been annihilated, leaving only a small remainder in 1987. Microbiological investigation on morphology and ontogenesis of the causative agent as well as environmental factors strongly indicated the presence of the crayfish Aphanomyces astaci Schikora. Reinfection of healthy animals under controlled laboratory conditions with zoospores obtained from pure cultures of the causative agent, yielded identic symptoms and course of disease and re-identification of the fungus was successful. Two lakes with high absolute electrolyte content and inverted Ca:Mg ratios showed a low disease incidence and harvesting continued through 1987. |
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