The use of probiotics in fish feed for intensive aquaculture to promote healthy guts

Abstract

The use of probiotics in feed for fish and its inclusion in intensive aquaculture to promote healthy gut is
growing. The need for alternative measures that will perform closely and effectively to the use of antibiotics
after its annulment in European Union (EU) in 2006 is an issue which call for concern. Several definitions of
probiotics mainly for aquaculture were also dig out from published papers. Among them is a definition
considered appropriate for aquaculture which is described as” any microbial cell provided via the diet or
rearing water that benefits the host fish, fish farmer or fish consumer, which is achieved, in part at least, by
improving the microbial balance of the fish”. In this context, they regard direct benefits to the host as
immuno-stimulants, improved disease resistance, reduced stress response, improved gastro intestinal
morphology and benefits to the fish farmer or consumer. The benefits to the fish farmer and consumers
includes improved fish appetite, growth performance, feed utilization, improvement of carcass quality, flesh
quality and reduced malformations. The mode of action with benefits of probiotics in aquaculture from
published journals was also looked into. The use of probiotics is growing especially as new strains were
being discovered that can withstand processing stress in feed manufacturing. But process optimization
knowledge to effectively work with these additives is insufficient. Combination of strain isolated from the
gastro-intestinal (GI) tracts of host animal had also being proving to be effective. Need to find proper
parameters to work with probiotics will be of great importance to the feed industry in the near future and
the stability of the strains of probiotics as a synbiotic relation with prebiotics. Examples and effects of
known strains were also stated and the future perspective of probiotics for fish.