. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. OYSTERS EXPOSED TO A DINOFLAGELLATE 323. Figure 7. Newly set spat. PAS staining of plastic-embedded, thick- sectioned spat. (A) A mixed-diet-fed animal shows positive PAS staining of dinoflagellates in the perivisceral space (1) and accumulation bodies in the absorptive cells (2). (B) A T-ISO-fed animal shows no PAS staining in the perivisceral space (1) or in the absorptive cells of the digestive gland (2). Lipid granules are numerous in the intestine (3), and many absorptive cell nuclei are dense (4). (Bar = 40 urn.) Juven
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. OYSTERS EXPOSED TO A DINOFLAGELLATE 323. Figure 7. Newly set spat. PAS staining of plastic-embedded, thick- sectioned spat. (A) A mixed-diet-fed animal shows positive PAS staining of dinoflagellates in the perivisceral space (1) and accumulation bodies in the absorptive cells (2). (B) A T-ISO-fed animal shows no PAS staining in the perivisceral space (1) or in the absorptive cells of the digestive gland (2). Lipid granules are numerous in the intestine (3), and many absorptive cell nuclei are dense (4). (Bar = 40 urn.) Juveniles Juvenile oysters that had been feeding on natural Mil- ford Harbor phytoplankton amended with cultured algae showed two different responses when subsequently ex- posed to experimental diets. Oysters fed T-ISO alone, or the 'A EXUV + % T-ISO diet, filtered the entire ration rapidly, produced normal fecal strands, and began growing immediately upon experimental feeding (Fig. 8). In con- trast, oysters fed EXUV alone or the % EXUV + 'A T- ISO diet filtered the ration, but produced pseudofeces and grew poorly for the first week or two of experimental feed- ing. Thereafter, most oysters produced normal fecal strands and grew at rates the same as or higher than those on other diets (Table IV). Histologic observations of oysters from each feeding regime sampled at the end of the experiment revealed that although the appearance of the absorptive cells in the digestive diverticula varied with diet, all were generally healthy except the negative controls (starved). Animals fed T-ISO showed absorptive cells with moderately co- lumnar outlines and consistent foamy, vacuolated cyto- plasm (Fig. 9A). In addition to generally poorly developed organ systems, starved oysters showed digestive diverticula cells that were cuboidal to low-columnar in outline with vacuolated/fine granular cytoplasm (Fig. 9B). In general, animals fed partially or wholly on EXUV had abundant columnar epithelia wi
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
