Evaluation of Mannan oligosaccharides (MOS) in balanced diets for tropical gar juveniles (Atractosteus tropicus)

Antecedentes: Los prebióticos son polisacáridos no digestibles por el huésped, pero, por otro lado, son los encargados de estimular la actividad de microorganismos benéficos en el sistema digestivo, lo que puede maximizar la ganancia en peso, la conversión alimenticia y la activación de la respuesta inmune. Los oligosacáridos de manano (MOS) han sido evaluados en varias especies de peces de importancia comercial. Objetivos: Determinar el efecto de diferentes niveles de MOS integrados en dietas balanceadas para juveniles de Atractosteus tropicus sobre el crecimiento, parámetros productivos, supervivencia, índices somáticos y actividad de enzimas digestivas. Métodos: Se evaluaron por triplicado seis dietas experimentales con inclusión de MOS (0.0, 0.2, 0.4, 0.6 y 0.8%) y una dieta control de trucha (DC) durante 62 días. Se distribuyeron 180 juveniles (5.11 ± 0.08 g) en un sistema de recirculación con 18 tanques de 70 L con flujo de 10 L min-1. Resultados: La supervivencia en todos los tratamientos fue superior al 96%. La dieta 0.2% de MOS presentó los valores más altos en peso ganado (WG), tasa específica de crecimiento (SGR) y tasa de eficiencia proteínica (PER), y el menor valor en tasa de conversión alimenticia (FCR). El índice hepatosomático (HSI) fue mayor para el tratamiento 0.4%, mientras que el índice viscerosomático fue mayor para los tratamientos 0.4% y 0.6%. Todas las actividades enzimáticas determinadas mostraron diferencias entre tratamientos (proteasa ácida, proteasa alcalina, tripsina, quimotripsina, leucina aminopeptidasa, carboxipeptidasas, lipasas, α-amilasa, fosfatasas ácidas y fosfatasas alcalinas). Conclusiones: La suplementación de 0.2% de MOS en dietas para juveniles de A. tropicus genera beneficios en el crecimiento y el rendimiento productivo. La inclusión de MOS en dietas para juveniles de A. tropicus modifica los índices somáticos y la actividad de enzimas digestivas en juveniles.Background: Prebiotics are polysaccharides that cannot be digested by the host; however, they generate benefits by stimulating the activity of beneficial microorganisms in the digestive system, which can maximize weight gain, feed conversion, and stimulate the immune response. Mannan oligosaccharides (MOS) have been evaluated in several fish species of commercial importance. Goals: Determine inclusion effects of different MOS levels in balanced diets for juveniles of Atractosteus tropicus on the growth, productive parameters, survival, somatic indexes, and activity of digestive enzymes. Methods: Six experimental diets including MOS (0.0, 0.2, 0.4, 0.6, and 0.8%) and a trout control diet (DC) were designed, manufactured, and evaluated in triplicate during 62 days. A hundred and eighty juveniles (5.11 ± 0.08 g) were distributed in a recirculation system with 18 tanks of 70 L with a flow of 10 L min-1. Results: The 0.2% MOS diet produced the highest values in weight gained (WG), specific growth rate (SGR), and protein efficiency rate (PER) and the lowest value in feed conversion rate (FCR). Survival in all treatments was greater than 96%. The hepatosomatic index was higher for the 0.4% treatment, while the viscerosomatic index was higher for the 0.4% and 0.6% treatments. All the enzymatic activities (acid protease, alkaline protease, trypsin, chymotrypsin, leucine aminopeptidase, carboxypeptidases, lipases, α-amylase, acid phosphatases, and alkaline phosphatases) showed significant differences by the inclusion of MOS in the diet. Conclusions: Supplementation of 0.2% MOS in diets for juveniles of A. tropicus, generates benefits in growth and productive performance. The inclusion of MOS in diets for juveniles of A. tropicus modifies somatic indices and the activity of digestive enzymes of juveniles.info:eu-repo/semantics/publishedVersio

Graded levels of dietary pink oyster mushroom, Pleurotus djamor meal, affect growth, feed efficiency, lipase activity, and fiber content in final whole body of fingerlings of the Nile tilapia, Oreochromis niloticus (Actinopterygii: Cichliformes: Cichlidae)

The presently reported study was aimed to determine the effects of graded levels of dietary pink oyster mushroom (Pleurotus djamor) meal (POMM), in growth, feed efficiency, protein utilization, digestive enzymes activities, and whole-body proximate composition of Nile tilapia, Oreochromis niloticus (Linnaeus, 1758), fingerlings (0.3 ± 0.01 g). The experimental design included a control diet (POMM0) formulated with soybean meal, as the main protein source, and four diets designed with increasing levels of POMM: 25% (POMM25); 50% (POMM50); 75% (POMM75); and 100% (POMM100). Experimental diets were administered to 420 fish, randomly distributed in 15, 100-L tanks. The feeding experiment lasted 45 days. Diets and the final whole body were submitted to a proximate composition analysis. Growth, feed efficiency, protein utilization, and digestive enzyme activities were assessed. Compared to POMM0 and POMM25, weight gain (WG), and specific growth rate (SGR), significantly (P < 0.05) decreased in fish that were fed POMM50, POMM75, and POMM100%. Feed conversion ratio (FCR), protein efficiency ratio (PER), and survival rate (SR) were not significantly affected by experimental diets. Daily feed intake (DFI), and daily protein intake (DPI), decreased as POMM increased in diets. Compared to POMM0 experimental group, condition factor (K), showed a significantly higher value in fish that were fed POMM50, and POMM100 experimental diets. Crude fiber of the final whole body of POMM100 resulted in significantly higher (P < 0.05) compared to that shown in fish fed the rest of the experimental diets. Acid and alkaline proteases, trypsin, chymotrypsin, leucine aminopeptidase, and amylase of Nile tilapia fingerlings, were not significantly affected by experimental diets. Compared to fish fed POMM0 and POMM25 diets, experimental fish fed POMM50, POMM75, and POMM100 showed a reduction in lipase activity. In conclusion, a POMM level higher than 25% affects growth and lipase activity. While a POMM level higher than 50% affects fiber content in a whole body of the final fish

Graded levels of dietary pink oyster mushroom, Pleurotus djamor meal, affects growth, feed efficiency, lipase activity and fiber content in final whole body of Nile tilapia fingerlings, Oreochromis niloticus

Expansion of aquaculture industry is evidently accompanied by an urgent necessity of aquaculture feed production. Traditionally, fish meal (FM) and soybean meal (SBM) have been the primary protein source ingredient in aquaculture diets.  However, over exploitation of these commodities has conducted to their unsustainability. Hence, research of unconventional protein alternatives has emerged. Mushroom meal is one of them. To date, mushroom meals have been investigated when supplemented in low levels in aquaculture diets. Furthermore, effects of diets supplemented with mushroom meals have assessed different parameters such as, haematology, immunity, anti–bacterial & anti–oxidant activities, and heat stress. Present study, is aimed to study the effects of graded levels of dietary pink oyster mushroom (Pleurotus djamor) meal (POMM), in growth, feed efficiency, protein utilization, digestive enzymes activities and whole body proximate composition of Nile tilapia (Oreochromis niloticus) fingerlings. Experimental design included a control diet (POMM0) formulated with soybean meal, as main protein source, and four diets designed with increasing levels of POMM: 25%(POMM25); 50%(POMM50); 75%(POMM75); and 100%(POMM100). Experimental diets and final whole body were submitted to a proximate composition analysis. Growth, feed efficiency, protein utilization, and digestive enzyme activities were assessed.  Compared to POMM0 and POMM25, weight gain (WG), and specific growth rate (SGR), significantly (