Animal performance and welfare of giant freshwater prawn (Macrobrachium rosenbergii) subjected to feed restriction

Behavior activities of giant freshwater prawn Macrobrachium rosenbergii juvenile, their performance, and acquired lesions when under temporary feed restrictions were analyzed. Five animals/experimental units (10 prawns/m2 ) were employed for treatments DFL ­ daily feed supply in the light phase; DFD ­ daily feed supply in the dark phase; AFL ­ alternating feed supply in the light phase; and AFD ­ alternating feed supply in the dark phase, for a 24-hour period, with four replications each. Prawns were fed a pellet diet, twice a day, with 10% of their biomass/day. Specimens were monitored during 60 consecutive days, with behavior recording daily and weighed every 10 days, with assessment of lesions and/or amputated limbs at the end of the experimental period. Types of behavior comprised exploring, grooming, inactivity, crawling, swimming, excavation, burrowing, agonism, and feed ingestion by scan sampling, with instantaneous registration every 60 s, in 15-min windows, before and after feed, in light and dark phases. Feed restricted in alternate days during light and dark phases did not interfere in growth or survival of the specimens, with increase in apparent feed intake and less feed conversion ratio and specific growth rate. Agonistic behavior was higher in specimens with feed restrictions, with an increase in the number of lesions and amputations. The above demonstrates welfare decrease in farmed M. rosenbergii and depreciation in the quality of the final product.(AU)

Replacement of protein source in practical diets for Amazon River Prawn / Substituição de fonte proteica em dietas práticas para Camarão-da-Amazônia

The aim of this study was to evaluate the best level of substitution of fish meal (FM) by soybean meal (SBM), as protein source in practical diets for juveniles of Macrobrachium amazonicum. Juveniles, with initial mean weight of 0.16 ± 0.66 g, were stocked at a density equivalent to 150 juveniles m-2 in a recirculating aquaculture system. Treatments consisted of the proportions of fish meal and soybean meal (FM:SBM) in diets, namely: 0: 100, 20:80, 40:60, 70:30, 100:0 with five replicates per treatment. At the end of the 45 days trial, prawns were counted, measured, weighed, and the bromatological analysis of the whole body was performed. Survival remained above 94% in all treatments (p>0.05). A corporal bromatological analysis showed significant among treatments only for crude protein (p <0.05). The results of the production performance showed that the inclusion of up to 30% of SBM in replacement for FM (70:30) did not interfere, significantly, in the performance of the prawns (p>0.05), making possible the use of soybean meal in diets for juveniles of Amazonian river prawn.(AU)

O objetivo deste trabalho foi avaliar o melhor nível de substituição da farinha de peixe (FP) pelo farelo de soja (FS), como fonte de proteína em dietas práticas para juvenis de Macrobrachium amazonicum. Juvenis com peso médio inicial de 0,16 ± 0,66 g foram estocados em uma densidade equivalente a 150 juvenis m-2 em sistema de recirculação. Os tratamentos consistiram das seguintes proporções de farinha de peixe e farelo de soja (FP:FS): 0:100, 20:80, 40:60, 70:30, 100:0 com cinco repetições por tratamento. Ao final de 45 dias de experimento, os camarões foram contados, medidos e pesados, bem como foi realizada análise bromatológica corporal. A sobrevivência manteve-se superior a 94% em todos os tratamentos (p>0,05). A análise bromatológica corporal apresentou diferenças significativas entre os tratamentos apenas para proteína bruta (p<0,05). Os resultados da análise de desempenho zootécnico demonstraram que a inclusão de até 30% de FS em substituição a FP (70:30) não interferiu significativamente no desempenho dos camarões, possibilitando uso do farelo de soja em dietas para juvenis de camarão amazônico.(AU)

Replacement of protein source in practical diets for Amazon River Prawn / Substituição de fonte proteica em dietas práticas para Camarão-da-Amazônia

The aim of this study was to evaluate the best level of substitution of fish meal (FM) by soybean meal (SBM), as protein source in practical diets for juveniles of Macrobrachium amazonicum. Juveniles, with initial mean weight of 0.16 ± 0.66 g, were stocked at a density equivalent to 150 juveniles m-2 in a recirculating aquaculture system. Treatments consisted of the proportions of fish meal and soybean meal (FM:SBM) in diets, namely: 0: 100, 20:80, 40:60, 70:30, 100:0 with five replicates per treatment. At the end of the 45 days trial, prawns were counted, measured, weighed, and the bromatological analysis of the whole body was performed. Survival remained above 94% in all treatments (p>0.05). A corporal bromatological analysis showed significant among treatments only for crude protein (p 0.05), making possible the use of soybean meal in diets for juveniles of Amazonian river prawn.

O objetivo deste trabalho foi avaliar o melhor nível de substituição da farinha de peixe (FP) pelo farelo de soja (FS), como fonte de proteína em dietas práticas para juvenis de Macrobrachium amazonicum. Juvenis com peso médio inicial de 0,16 ± 0,66 g foram estocados em uma densidade equivalente a 150 juvenis m-2 em sistema de recirculação. Os tratamentos consistiram das seguintes proporções de farinha de peixe e farelo de soja (FP:FS): 0:100, 20:80, 40:60, 70:30, 100:0 com cinco repetições por tratamento. Ao final de 45 dias de experimento, os camarões foram contados, medidos e pesados, bem como foi realizada análise bromatológica corporal. A sobrevivência manteve-se superior a 94% em todos os tratamentos (p>0,05). A análise bromatológica corporal apresentou diferenças significativas entre os tratamentos apenas para proteína bruta (p<0,05). Os resultados da análise de desempenho zootécnico demonstraram que a inclusão de até 30% de FS em substituição a FP (70:30) não interferiu significativamente no desempenho dos camarões, possibilitando uso do farelo de soja em dietas para juvenis de camarão amazônico.