Effectiveness of aluminosilicate-based products for detoxification of aflatoxin-contaminated diets for juvenile Pacific white shrimp, Litopenaeus vannamei

The safety and effectiveness of four aluminosilicate-based products (Novasil Plus, Zeolex Extra, Mycofix Select, and Fixat) were tested for 42 days on juvenile Pacific white shrimp, Litopenaeus vannamei, fed diets containing corn grains that had been previously inoculated with Aspergillus parasiticus and then sterilized. Two control diets, one uncontaminated and another contaminated with the contaminated corn grain, were elaborated to contain a final concentration of 0 and 75 mu g kg(-1) total aflatoxins. Both diets were formulated to contain 38% crude protein and 8% lipids. Eight more diets were manufactured from the previous two to contain each of the test products at inclusion levels of 2.5 to 5.0 g kg(-1), in accordance with the inclusion level recommended by the manufacturer. Mycofix Select and Fixat inclusion improved diet stability (12-16%). Water absorption capacity in the diets increased (from 2% to 17%) due to the supplementation of aluminosilicates. Feeding aflatoxin-contaminated diets to Pacific white shrimp resulted in lower feed intake and weight gain without affecting the feed conversion ratio, nitrogen retention, and survival. Feeding the uncontaminated diets supplemented with Zeolex Extra, Mycofix Select, and Fixat resulted in a slight reduction in feed intake without affecting growth rate, nitrogen retention, or survival. Conversely, the inclusion of Novasil Plus in the uncontaminated diet did not affect feed intake and an 8% growth rate improval was observed. Three of the tested products failed to provide complete restoration of feed consumption and shrimp growth rate when added to the aflatoxin-contaminated diet.