Pacific white shrimp, Penaeus vannamei, were tested in two indoor tria
ls to identify dietary aflatoxin B-1 (AF B-1) levels that adversely af
fect performance and to describe histopathological changes. Trial I (0
-15 000 ppb nominal AF B-1 levels; 21-day duration; 1.61 g per shrimp
initial mean weight) was a range-finder test for acute and chronic AF
B-1 toxicity, including histopathological responses. Trial II (0-900 p
pb AF B-1; 56-day duration; 1.51 g per shrimp initial mean weight) qua
ntified AF B-1 effects on growth, feed conversion and apparent digesti
bility coefficients for digestible energy, dry matter and crude protei
n. AF B-1 at 15 000 ppb caused 100% mortality within 2 weeks. Abnormal
hepatopancreas and antennal gland tissues were caused by 2 weeks of A
F B-1 at 50 ppb. Feed conversion and growth were significantly affecte
d at approximate to 400 ppb AF B-1. Apparent digestibility coefficient
s decreased significantly at 900 ppb AF B-1.