Abstract Searching for alternative ingredients to replace fishmeal in balanced feeds for the culture of aquatic organisms is a relevant task to promote the sustainability of aquaculture, an industry that satisfies the demand for aquatic foods for human consumption. Black soldier fly larvae meal and single cell protein meals such as those from bacteria and yeasts, have relatively high protein contents, favorable amino acid profiles, and can be produced using by-products or organic residues from animal or vegetable sources; therefore, their production is sustainable and low-priced, as compared to that of fishmeal. This non scholarly article is intended to divulge the most relevant features of these alternative feedstuffs, and to show some of the most significant examples of their use in balanced feeds for cultured species of commercial relevance.

Resumen La búsqueda de ingredientes alternativos a la harina de pescado para su inclusión en alimento balanceado utilizado para el cultivo de organismos acuáticos es una tarea importante para la sustentabilidad de la acuacultura, una industria que satisface la demanda de alimentos acuáticos para el consumo humano. La harina de larva de mosca soldado negro y de organismos unicelulares como bacterias y levaduras, presentan contenidos de proteína relativamente altos, perfiles de amino ácidos favorables y se producen utilizando subproductos o residuos orgánicos de origen animal o vegetal, por lo que su producción es sustentable y de bajo costo, en comparación con la harina de pescado. El presente artículo de divulgación tiene por objeto dar a conocer las características más relevantes de estos insumos alternativos, así como mostrar algunos de los ejemplos más significativos de su utilización en alimentos balanceados para el cultivo de especies de importancia comercial.

Abstract In the present study, the use of the microalgae Arthrospira sp., Chlorella sp., Isochrysis sp., and Nannochloropsis sp., as partial constituents in diets for Nile tilapia (Oreochromis niloticus), was evaluated in static tanks in a 53-day study, with a commercial diet containing 45% crude protein as a control treatment. Then, we replaced 25% of this diet with meals derived from each of the four microalgae species. Analysis of variance was employed to evaluate fish growth performance. Fish fed the diets with the microalgae Arthrospira sp. and Chlorella sp. had growth performance comparable to that of fish fed the control diet, as evaluated by growth parameters, such as final weight, weight gain, and percent weight gain, among others. In contrast, growth of fish receiving the microalgae Isochrysis sp. and Nannochloropsis sp. was significantly lower. Results of the present study indicate that the use of 25% of Arthrospira sp. and Chlorella sp. meals incorporated into the diet of O. niloticus does not compromise fish development, although there seems to be an opportunity for a further increment of the replacement level.

Resumen El presente estudio evaluó el uso de las microalgas Arthrospira sp., Chlorella sp., Isochrysis sp. y Nannochloropsis sp. como constituyentes parciales del alimento balanceado para tilapia del Nilo ( Oreochromis niloticus ) bajo condiciones de cultivo estático en un estudio de 53 días de duración. Un alimento balanceado comercial con contenido de proteína cruda de 45% se utilizó como dieta control, mismo que se molió finamente y se reconstituyó incorporando, a un nivel de inclusión de 25% de la dieta, las harinas de las cuatro especies de microalgas mencionadas. Se analizaron parámetros de producción de tilapia, incluyendo índices de crecimiento y supervivencia, mediante análisis de varianza. Los índices de crecimiento, tales como peso final, peso ganado y porcentaje de peso ganado de los peces alimentados con las microalgas Arthrospira sp. y Chlorella sp., así como la supervivencia, fueron similares a los de aquellos que recibieron la dieta control, mientras que el crecimiento de peces alimentados con las microalgas Isochrysis sp. y Nannochloropsis sp. fue inferior estadísticamente. Estos resultados indican que Arthrospira sp. y Chlorella sp. pueden ser incorporadas a un nivel de 25% del alimento balanceado sin afectar significativamente el crecimiento o la supervivencia de O. niloticus.

The marine bioprocessing industry offers great potential to utilize byproducts for fish meal replacement in aquafeeds. Jumbo squid is an important fishery commodity in Mexico, but only the mantle is marketed. Head, fins, guts and tentacles are discarded in spite of being protein-rich byproducts. This study evaluated the use of two jumbo squid byproduct hydrolysates obtained by acid-enzymatic hydrolysis (AEH) and by autohydrolysis (AH) as ingredients in practical diets for shrimp. The hydrolysates were included at levels of 2.5 and 5.0% of the diet dry weight in four practical diets, including a control diet without hydrolysate. Shrimp growth and survival were not significantly affected by the dietary treatments. Postharvest quality of abdominal muscle was evaluated in terms of proximate composition and sensory evaluation. Significantly higher crude protein was observed in the muscle of shrimp fed the highest hydrolysate levels, AH 5% (204.8 g kg- 1) or AEH 5% (201.3 g kg- 1). Sensory analysis of cooked muscle showed significant differences for all variables evaluated: color, odor, flavor, and firmness. It was concluded that Jumbo squid byproducts can be successfully processed by autohydrolysis or acid-enzymatic hydrolysis, and that up to 5.0% of the hydrolysates can be incorporated into shrimp diets without affecting growth or survival.