Date: 6 Jan 1998
From: Instituto de Pesca - Laboratorio de Biologia <ipescalb@eu.ansp.br>
To: aqua-l@killick.ifmt.nf.ca
QUESTION:
I am trying to find estimations about the wet weight of a rotifer Brachionus plicatilis. Could anybody help me ?
Fernando Andre Salles
Instituto de Pesca
Sao Paulo / Brasil
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COMMENTS 1:
The rotifer dry weight of Brachionus plicatilis (L-type) we are culturing is approximately 0.2 microgram. Making an estimate to wet weight I would guess 2 microgram.
Philippe Dhert <philippe.dhert@UGent.be>
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COMMENTS 2:
The wet weights for rotifers B plicatilis, in my experiments, were between 4 and 5 micrograms, with little difference between starved rotifers and those fed on microalgae or yeast.
Dry weights were between 0.3 and 0.5 micrograms.
Tom Lewis
Department of Agricultural Science
University of Tasmania
GPO Box 252-54
HOBART, Tasmania 7001
AUSTRALIA
phone (03) 6226 2620 fax (03) 6226 2642
International (+61 3) etc
email T.Lewis@utas.edu.au
http://www.antcrc.utas.edu.au/antcrc/micropro/nichols.html
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COMMENTS 3:
I am working with rotifers for larvae flatfish cultures and
other marine finfish in my University. A few years ago I did a research looking around for the same that you are looking for right now.
Loric length (micrometer) and dry weight (microgram) by differents authors for B. plicatilis:
Loric Dry
Length Weight Reference
99 - 281 0.16 Marine Biology, 10(1971):183-188
75 - 240 ---- Investigaciones Marinas, 11(8):1-29, 1974.
136 - 252 ---- Aquaculture, 27(1982):55-61
------ 0.33 Hydrobiologia, 104(1983):77-84
123 - 292 ---- Aquaculture, 37(1984):359-367
------ 0.17 Inf. Tecn. Inst. Esp. Oceanog., 2(1982):1-19
------ 0.15 - 0.75 Aquaculture, 14(1978):247 - 260
In my own research I found that 1 g (wet weight) have 500,000 rotifers (including eggs) and I do not make any difference between starved and fed rotifers. My rotifers had a size between 232+/-22 micrometer loric length.
German E. Merino
(Aquaculture Engineer)
Marine Aquaculture Center Manager
Universidad Catolica del Norte
P.O. Box 117
Coquimbo, CHILE
Phone/fax: (56)(51) 324163
(56)(51) 313475
e-mail: gmerino@nevados.cecun.ucn.cl