. The Biological bulletin. Biology; Zoology; Marine biology. 336 A. SCARBOROUGH AND E. WEIDXER. Figure 1. Young specimen of the smelt, Osmcrus mordax, experimentally infected with Glugca hertwigi. The yearly incidence of natural infections nears 90% in juveniles with consequent vast mortalities. Seven days post infection, xenomas (white arrows) develop proximate to larger 4-week-old "Glugea cysts" (black arrows). Bar represents mm. Experiment 2. Laboratory reared smelt (10 mm, 6 weeks post spawning) were fed spore-carrying zooplankton (cladocerans and copepods) on 2 consecutive d
. The Biological bulletin. Biology; Zoology; Marine biology. 336 A. SCARBOROUGH AND E. WEIDXER. Figure 1. Young specimen of the smelt, Osmcrus mordax, experimentally infected with Glugca hertwigi. The yearly incidence of natural infections nears 90% in juveniles with consequent vast mortalities. Seven days post infection, xenomas (white arrows) develop proximate to larger 4-week-old "Glugea cysts" (black arrows). Bar represents mm. Experiment 2. Laboratory reared smelt (10 mm, 6 weeks post spawning) were fed spore-carrying zooplankton (cladocerans and copepods) on 2 consecutive days. The plankton was first exposed to a spore suspension for 30 min, washed once with water, examined to ensure the presence of spores in their digestive tracts and then fed to the smelt. Experiment 3. Collected smelt (15 mm, approximately 8 weeks post spawning) were fed spore-carrying plankton as above. Experiment 4. Smelt from Experiment 1, 4 weeks after exposure to a spore suspension, were fed spore-carrying plankton as above. As a control, a number of laboratory reared and collected smelt were maintained unexposed to spores. Development of xenomas Young smelt from all tanks were observed and photographed with a Wild M-i Makroskope 5 days, 1, 2 and 3 weeks after spore feeding. Intestinal tissue from experimental and control smelt were prepared for microscopy as outlined above. - Number of smelt infected Experiment Source of Sample Method of Period of number smeltj size exposure incubation Light 50 (per host) 1 mixture of 20 spore suspension 28 davs 8 0 lab reared and collected 2 lab reared 5 spore-carrying plankton 7 days 0 5 3 collected 14 spore-carrying plankton 7 days 0 14 4* mixture 8 spore-carrying plankton 7 days 0 8 * Smelt from Experiment 1, carrying light infections 28 days after exposure to the spore sus- Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectb, booksubjectzoology
