Cyst production in the fairy shrimp, Streptocephalus proboscideus (Anostraca) in relation to algal and loricated rotifer diet
Por:
Ali A.J., Sarma S.S.S., Dumont H.J.
Publicada:
1 ene 1999
Resumen:
Adult fairy shrimps, Streptocephalus proboscideus (Frauenfeld, 1873) reared separately using algae (Scenedesmus acutus Meyen), a large loricate rotifer (Brachionus calyciflorus Pallas, 1766) and mixtures of algal and animal diets (1:1 ratio on a dry weight basis) at a rate of 17 ?g DW ml-1 day-1 produced a mean number of 184 ± 38, 111 ± 14, and 160 ± 14 cysts per brood, respectively. Of these, the rotifer-only diet was significantly inferior to both other food types. Measurements of cyst volume revealed an effect of food type. With all three types, S. proboscideus produced cysts in the size range of 3.0-9.0 x 106 ?m3. However, sizes smaller than 3.0 x 106 ?m3 occurred in algae-fed anostracans and those larger than 9.0 x 106 ?m3 in rotifer-fed individuals. When the mean cyst production was expressed in terms of volume instead of numbers, there was a suggestion that the mixture of algae and rotifers was the superior combination, while females reared on rotifers produced a significantly (38%) lower total cyst volume, Hatchability of cysts, either dried or un-dried, was not significantly different between treatments.
Filiaciones:
Ali A.J.:
Laboratory of Animal Ecology, University of Ghent, K. L. Ledeganckstraat 35, B-9000 Ghent, Belgium
Sarma S.S.S.:
Laboratory of Animal Ecology, University of Ghent, K. L. Ledeganckstraat 35, B-9000 Ghent, Belgium
Biology Career, Natl. Autonomous Univ. of Mexico, Campus Iztacala, A.P. 314, C.P. 54000, Av. Los Reyes, Tlalnepantla, Mexico
Dumont H.J.:
Laboratory of Animal Ecology, University of Ghent, K. L. Ledeganckstraat 35, B-9000 Ghent, Belgium
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