Replacement of fishmeal with commercial soybean meal and EnzoMeal in juvenile barramundi Lates calcarifer

This study investigates the impact of fishmeal replacement by soybean meal (SM) and improved SM known as EnzoMeal (EZ) on fish growth performance. The SM and EZ were used in five experimental diets: fishmeal (600 g/kg) as the control diet, 50% fishmeal replaced with soybean meal (SM50), 50% fishmeal replaced with EnzoMeal (EZ50), 100% fishmeal replaced with soybean meal (SM100) and 100% fishmeal replaced with EnzoMeal (EZ100). Fish in the control group gained the most weight, followed by those under the SM50 and EZ50 diets, while the least weight gain was observed in fish fed the SM100 and EZ100 diets. The specific growth rate (SGR) was higher in the control, but was not different between fish fed SM50 and EZ50, or between SM100 and EZ100. The highest feed intake occurred in the control but decreased sequentially from fish fed SM50 to fish fed EZ50, EZ100 and SM100. Protein digestibility was best in SM50, poorest in EZ100, but no difference between the control, EZ50 and SM100 diets. This study indicates that EnzoMeal, containing high crude protein (56%), is a potential source of plant meal to replace fishmeal in the barramundi diet, but low feed intake is a challenge when EnzoMeal is >300 g/kg.