Adult fairy shrimps, Streptocephalus proboscideus (Frauenfeld, 1873) reared separately using
algae (Scenedesmus acutus Meyen), a large loricate rotifer (Brachionus calyci orus 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 signi cantly 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 £ 106 ·m3. However, sizes smaller than
3:0£106 ·m3 occurred in algae-fed anostracans and those larger than 9:0£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 signi cantly (38%) lower total cyst volume. Hatchability of
cysts, either dried or un-dried, was not signi cantly different between treatments.
Adult fairy shrimps, Streptocephalus proboscideus (Frauenfeld, 1873) reared separately usingalgae (Scenedesmus acutus Meyen), a large loricate rotifer (Brachionus calyci orus Pallas, 1766)and mixtures of algal and animal diets (1 : 1 ratio on a dry weight basis) at a rate of 17 ·gDW ml 1 day 1 produced a mean number of 184 § 38, 111 § 14, and 160 § 14 cysts perbrood, respectively. Of these, the rotifer-only diet was signi cantly inferior to both other foodtypes. 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 £ 106 ·m3. However, sizes smaller than3:0£106 ·m3 occurred in algae-fed anostracans and those larger than 9:0£106 ·m3 in rotifer-fedindividuals. 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, whilefemales reared on rotifers produced a signi cantly (38%) lower total cyst volume. Hatchability ofcysts, either dried or un-dried, was not signi cantly different between treatments.
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