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Daily observations to determine age at swim bladder inflation and first feeding <br />were made with a dissecting microscope. Age at swim bladder inflation and first feeding <br />in each treatment was taken as the age at first observed occurrence in an individual larva <br />in the treatments. Newly hatched brine shrimp nauplii Anemia sp. were presented to <br />larvae twice daily ad libitum and presence or absence of food in the gut was documented <br />1 h later. Larvae were maintained in experimental treatments for 7 d after hatching and <br />then counted and measured. Larvae were maintained in the fifth incubation chamber for <br />all treatments until first feeding was observed. All larvae were examined daily for <br />obvious abnormalities (i.e., lack of eyes, spinal deformities, swim bladder anomalies). <br />Percent hatch, percent survival of larvae to d 7 (of embryos that hatched), and <br />percent of larvae with abnormalities (of embryos that hatched), were calculated from the <br />four replicates in each treatment. Percentages were transformed (aresine and square-root) <br />to stabilize statistical variances and normalize the data. Main effects of temperature at <br />three levels (18, 22, 26°C) and constant versus fluctuating temperature regimes and their <br />interaction (temperature x regime) were analyzed with fixed-effects two-factor analysis of <br />variance (ANOVA). The Tukey test for multiple comparisons was used if the overall F- <br />test was significant (P < 0.05). Statistical analyses were conducted with-the SAS <br />statistical package (SAS Institute 1988): The data for the 30°C constant temperature <br />treatment were excluded from statistical analyses because all larvae were deformed. <br />Results <br />Hatch.-- Mean hatch at 18, 22, and 26°C in constant and fluctuating regimes was <br />54-79% (Table 1) and did not differ significantly among treatments for main effects or for <br />13 <br />