Nutritional supplement of FOS enhances growth and immune system in tilapia larvae (Oreochromis niloticus)

Aquaculture is an essential economic activity worldwide, supplying the requirements of various nations. The larval stage is one of the most critical periods during the production cycle in aquaculture. To contribute to amplifying the knowledge related to viable methods to enhance this activity, the present study investigated the effects of prebiotic fructooligosaccharide (FOS) and the synthetic peptide GHRP-6 in the growth of fish, as well as its repercussions on a series of digestive enzyme activities and immune response parameters. Tilapias (Oreochromis niloticus) larvae were divided into three groups: group 1, fed with pre-formulated feed; group 2, fed with feed + FOS; group 3, fed with feed + GHRP-6. We measured the gain in size and weight at 72 and 87 days after starting the diets. At the end of treatment, we continue feeding the animals with a standard diet using the pre-formulated feed. We measured immune system parameters and digestive enzyme activities on larvae homogenate, focusing on lysozyme and antiprotease activity and α-amylase, trypsin and esterase activity, respectively. Results show a significant increment in size and weight in those fish fed with feed + FOS. Meanwhile, the primary enzyme activity was detected in those fish fed with feed + GHRP-6. On rough terms, both food combinations stimulated the immune system. Our study suggests that FOS and GHRP-6 could be desirable additives to incorporate into the tilapia larvae feeding and increase production efficiency. Keywords: aquaculture, digestive enzymes activity, FOS, GHRP-6, immune system, larvae