From: campbell@island.net (Chris Campbell)
To: AQUA-L@LISTSERV.ifmt.nf.ca
COLONIAL PROTOZOANS ON PRAWN LARVAE
QUESTION:
Does anyone have any experience with techniques to reduce colonization of prawn larvae? We are working with Pandalus platyceros and fear that this "fouling" is inhibiting ability to molt.
I am about to try formaldehyde (50 ppm for one hour) but am open to other suggestions.
Chris or Gill Campbell
The Cultured Crustacean Company Ltd of Newfoundland to Nanaimo.
Phone, message or fax 250 754 0040
Nanaimo, British Columbia, Canada
Email: campbell@island.net
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ANSWER:
Date:11 Apr 1997
From: clangell <clangell@eskimo.com>
To: AQUA-L@LISTSERV.ifmt.nf.ca
I had a similar problem with Macrobrachium rosenbergii larvae and
found formalin to be the only effective treatment. I was using a recirculating system with clam shell media in the biofilters. When we had an outbreak of Vorticella or similar protozoa, it was usually associated with a build up of particulate matter in the rearing water. We found that filtering through a gravity sand filter reduced the ciliate infestations considerably. You could also use a 20 or 50 micron cartridge filter. I was working in Bangladesh, so we didn't have such things available.
Charles Angell
Multiservices International
Email: clangell@eskimo.com
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