Chemoattractants: Their essentiality and efficacy in shrimp aquaculture

Abstract

Aquaculture serves as a sustainable source of good quality wholesome food and major input is feed. In recent years, considerable quantities of plant sources have been attempted for inclusion in shrimp feed, due to high demand and high cost of fishmeal. Plant-based ingredients are in general poor in attractability and palatability to aquatic species compared to marine sources. It is desirable to develop an economical and nutritious feed that is attractive and palatable for ensuring reduction of feed wastage. Chemoattractants nowadays are unavoidable in commercial shrimp feeds and are included either individually or in combination. The present review revealed that the various marine sources, in particular krill meal would be more effective for aquatic species, compared to those derived from vegetable origin and chemical compounds. In addition to acting as a feed attractant, marine sources serve as a potential fishmeal substitute due to their rich nutritional composition. However, certain biogenic amines present in these marine-based ingredients need to be examined before their use, since these amines when present in high concentrations reduces feed intake by producing undesirable odour. Use of a combination of chemoattractants would give a better effect, rather than using them individually and compounds from plant origin have limited beneficial effects. The present review concludes that incorporation of chemoattractants would be beneficial in formulation of enriched and economical feeds with better attractability and palatability. The selection of suitable attractant and their supplementation at correct proportion is significantly more important to avoid undesirable effects in cultured shrimp. Further field-based research is needed to predict the actual effects of chemoattractants on farmed shrimp and to provide a sustainable base for the expansion of shrimp aquaculture sector, by reducing feed wastage.

Effect of Calanus finmarchicus Hydrolysate Inclusion on Diet Attractiveness for Whiteleg Shrimp (Litopenaeus vannamei)

“…However, the intakes of low and high FM control diets were found to be equal (Table S3 in Supplementary Data), and the relatively moderate inclusion rates of attractive ingredients thus had a larger influence on feed intake. The effects of attractive ingredients are supposedly higher when used in combination rather than individually [9], which can help explain the increased differences among the high FM diets compared to the low FM group.…”

“…Alkaline and neutral amino acids, such as glycine, proline, taurine, and valine, and derivatives, like betaine, are known to have chemoattractive properties for olfaction and/or ingestion in carnivorous species [9,10]. Looking for further answers as to why diets with CH showed higher attractiveness, a comparison of the chemoattractant amino acids in the attractive ingredients was made.…”

“…In addition to increased feed intake, supplementation of taurine in diets for juvenile whiteleg shrimp has been found to improve growth performance, metabolism, immunity, anti-oxidant capacity, and intestinal health [35][36][37][38][39]. Metabolomic fingerprinting of C. finmarchicus has also revealed that one of its major metabolites is betaine [40], which is a highly soluble glycine derivative with chemoattractive properties for both fish and shrimp [8][9][10][41][42][43]. Alkaline and neutral amino acids, such as glycine, proline, taurine, and valine, and derivatives, like betaine, are known to have chemoattractive properties for olfaction and/or ingestion in carnivorous species [9,10].…”

“…Metabolomic fingerprinting of C. finmarchicus has also revealed that one of its major metabolites is betaine [40], which is a highly soluble glycine derivative with chemoattractive properties for both fish and shrimp [8][9][10][41][42][43]. Alkaline and neutral amino acids, such as glycine, proline, taurine, and valine, and derivatives, like betaine, are known to have chemoattractive properties for olfaction and/or ingestion in carnivorous species [9,10]. Looking for further answers as to why diets with CH showed higher attractiveness, a comparison of the chemoattractant amino acids in the attractive ingredients was made.…”

“…The inclusion of attractants that activate the Fishes 2024, 9, 134 2 of 10 chemosensory systems is common to increase the attractiveness of diets with high plant protein content [8]. Natural chemoattractants for shrimp are often marine ingredients rich in free amino acids, nucleotides, nucleosides, quaternary ammonium compounds, phospholipids, and biogenic amines, which are recognized by the chemosensory system of aquatic animals when locating and ingesting feed materials [9,10]. In addition, dietary inclusion of marine ingredients in water-soluble form (e.g., protein hydrolysates) has been found especially attractive and palatable [11,12].…”