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Fishery Bulletin 107(3) 
and well developed digestive system (Fig. 4B). Artemia 
spp., which were first offered 12 DAH, were observed 
in the stomach of larvae along with rotifers at 14 DAH. 
Artificial feeds, which were offered beginning 10 DAH, 
could not be detected through observation with a dis- 
secting microscope. Although Florida pompano lack a 
gas bladder, approximately 10% of larvae consumed 
small air bubbles (129-235 pm) that were trapped in 
the peritoneal cavity from 5 to 10 DAH. 
Swimming ability improved and larvae were notice- 
ably stronger with pectoral fin development at four to 
five DAH. The dorsal, pelvic, and anal fins began de- 
veloping at nine DAH and the formation of the caudal 
fin and fin rays was observed at 12 DAH. Morphologi- 
cal and osteological development at six and seven DAH 
was noticeably more advanced in the third rearing trial 
than in specimens collected in the previous trials. As 
evidenced by the formation of hypural elements, no- 
tochord flexion was first observed at 10 to 12 DAH in 
the first two rearing trials. In the third rearing trial, 
notochord flexion was observed 8 to 11 DAH. Larvae 
completed flexion at 12 to 16 DAH in the first two rear- 
ing trials, and at 11 to 12 DAH in the third rearing 
trial. Postflexion and the onset of transformation were 
apparent at 15 to 18 DAH in the first two rearing tri- 
als (Fig. 5A), and at 13 to 14 DAH in the third rearing 
trial. Larvae in the first two rearing trials completed 
transformation and had a full complement of fins and 
scales by 20 DAH (Fig. 5B), whereas fish in the third 
rearing trial completed transformation by 17 DAH. 
Differences in growth were observed among trials. 
Mean growth rates calculated from TL measurements 
were 0.22 ±0.04, 0.23 ±0.12, and 0.35 ±0.09 mm/d for 
each of the larval rearing trials. Larvae in the third 
trial grew faster than fish in the first and second trial. 
Measured growth parameters of Florida pompano larvae 
reared from one through 20 DAH are summarized in 
Table 1. Statistical analysis evaluating TL and age (Fig. 
6) revealed no significant differences among growth 
rates from hatching through six DAH (P=0.84); howev- 
er, a significant difference in growth rate was detected 
for larvae reared in the third trial (P= 0.007) after seven 
DAH (Table 2). No significant differences were detected 
between the first two rearing trials (P=0.12). 
Similar results were observed with a statistical anal- 
ysis of larvae, where SL and age (Fig. 7) were used 
to determine growth rates. Mean growth rates were 
0.18 ±0.03, 0.18 ±0.10, and 0.31 ±0.08 mm/d for each 
of the larval rearing trials. No significant differences 
were observed among growth rates from hatch through 
eight DAH (P- 0.75); however, a significant difference in 
growth rate was detected for larvae reared in the third 
Figure 4 
Early stage Florida pompano ( Trachinotus carolinus ) 
reared in the laboratory and photographed with a dis- 
secting microscope and digital camera. (A) Larva at 
three days after hatching (DAH) near initiation of exog- 
enous feeding and with eye pigmentation. (B) Larva at 
7 DAH with fully formed digestive system, distinctive 
pigmentation, and initial development of head spines. 
Scale represents 1 mm. 
