Growth, feed intake, survival, and histological response of white shrimp Litopenaeus vannamei fed diets containing grains naturally contaminated with aflatoxin

Abstract

INTRODUCCIÓNEl objetivo final de los fabricantes y proveedores de alimento acuícola es asegurar que los alimentos producidos sean seguros y saludables (Tacon y Metian 2008 ABSTRACT. Two feeding trials were carried out to evaluate the effect of diets containing corn or peanut grains naturally contaminated with aflatoxins on the growth, feed intake, survival, and histological response of the white shrimp Litopenaeus vannamei. In trial 1, four experimental diets were formulated to contain 0, 500, 1000, and 2000 g kg -1 of total aflatoxins (TA) and fed to L. vannamei juveniles for 28 days. In trial 2, six experimental diets were formulated to contain 0, 10, 20, 40, 60, and 120 g kg -1 TA and fed to L. vannamei juveniles for 64 days. Feed intake and weight gain were significantly affected by the presence of aflatoxins from naturally contaminated grains. Feed conversion rate increased significantly from a level of inclusion of 60 g kg -1 . Survival was significantly reduced only for shrimp fed diets supplemented with 1000 and 2000 g kg -1 TA. Shrimp exposed to higher aflatoxin inclusion levels presented significantly lower lipid vacuole levels in R-cells (12-28%), lower B-cell activity, and lower mitotic E-cell activity. Tubular epithelial atrophy increased from the inclusion level of 20 g kg -1 . Hepatopancreatocyte sloughing was significantly higher in shrimp fed diets supplemented with 1000 and 2000 g kg -1 TA. It is worth noting that shrimp fed 40 g kg -1 TA presented a high hepatopancreatocyte sloughing coefficient. Based on these results we conclude that the presence of aflatoxins, even at low levels, reduces feed intake and weight gain, and alters the cells of the hepatopancreas.Key words: aflatoxin, shrimp, growth, Litopenaeus vannamei. RESUMEN.Se llevaron a cabo dos bioensayos para evaluar el efecto de granos de maíz y maní contaminados naturalmente con aflatoxinas sobre el crecimiento, consumo de alimento, supervivencia y daños histológicos de juveniles del camarón blanco Litopenaeus vannamei. Para el bioensayo 1, se formularon cuatro dietas con 0, 500, 1000 y 2000 g kg -1 de aflatoxinas totales (AT) y se proporcionaron a juveniles de L. vannamei durante 28 días. Para el bioensayo 2, se formularon seis dietas con 0, 10, 20, 40, 60 y 120 g kg -1 AT y se proporcionaron a juveniles de L. vannamei durante 64 días. El consumo de alimento fue significativamente afectado por la presencia de aflatoxinas. La tasa de conversión alimenticia incrementó significativamente a partir de un nivel de inclusión de 60 g kg -1 . La supervivencia fue significativamente reducida solamente en los camarones que fueron alimentados con las dietas suplementadas con 1000 y 2000 g kg -1 AT. Los camarones expuestos a los niveles de inclusión altos presentaron un menor nivel de vacuolas lipídicas en las células R (12-28%), y una menor actividad de las células B y de la actividad mitótica de las células E. La atrofia de los túbulos del epitelio se incrementó a partir de un nivel de inclusión de 20 g kg -1 . La descamación de las ...

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

“…Reduction in feed intake might be caused by the presence of non-palatable compounds generated in the grain during mold growth. No reduction in survival was found in the present study using low dietary aflatoxin levels, which is in accordance with that reported by Tapia-Salazar et al (2012) for L. vannamei and by Boonyaratpalin et al (2001) and Gopinath and Raj (2009) for P. monodon fed contaminated diets (from 15 to 2500 µg aflatoxin kg -1 diet).…”

“…The adverse effects on feed intake and growth observed in shrimp fed aflatoxin-contaminated diets are similar to those previously reported for other shrimp species (Boonyaratpalin et al 2001, Soonngam and Hutacharoen 2007, Tapia-Salazar et al 2012. Reduction in feed intake might be caused by the presence of non-palatable compounds generated in the grain during mold growth.…”

“…An important reduction in feed 2 intake, depression of growth performance, immune suppression, and hepatic lesions have been observed in rainbow trout (Arana et al 2011), carp (Mohapatra et al 2011), tilapia (Shehata et al 2009), catfish (Dӧll et al 2010, and shrimp (Boonyaratpalin et al 2001, Soonngam and Hutacharoen 2007, Gopinath and Raj 2009, Tapia-Salazar et al 2012 fed an aflatoxin-contaminated diet. Several detoxifying products are commercially available to inactivate mycotoxins in animal feeds, and their detoxifying effect involves physical adsorption, binding, and trapping of toxic substances (Kolossova et al 2009), followed by their elimination together with the detoxifier.…”

Apparent digestibility of dry matter, crude protein, and amino acids of six rendered by-products in juvenile Litopenaeus vannamei

“…El extracto libre de nitrógeno fue calculado por diferencia. La pérdida de nutrientes en agua marina fue estimada de acuerdo con la técnica documentada por Tapia-Salazar et al (2013). El contenido de cromo fue determinado utilizando el método descrito por Bolin et al (1952) …”

“…The bromatological composition of the ingredients, diets, and feces was determined as follows: AOAC methods 930.15, 990.03, 942.05, and 962.09B were used to determine the moisture, crude protein, ash, and fiber contents, respectively (AOAC 1997); the Soxhlet method was used to determine the lipid content (Tecator 1997); nitrogen free extract was calculated by difference; nutrient loss in seawater was determined according to Tapia-Salazar et al (2013); chrome content was determined according to the method described by Bolin et al (1952) and modified by Cruz-Suárez et al (2009); and amino acids were determined according to Llames and Fontaine (1994) and Fontaine (2003).…”