Aquaculture and Fisheries Management 1993, 24, 613-624 Effect of feeding attractants on the behaviour and performance of juvenile Penaeus monodon Fabricius R HARTATI & M R P BRIGGS Institute of Aquaculture, University of Stirling, Stirling, Scotland Abstract A study was conducted to obtain a measure of the potency of some potential and commercially used feeding attractants for Penaeus monodon Fabricius Behavioural trials monitoring the feeding response of the shrimp were used to gauge the attractant qualities of the substances, A growth trial recording the feed intake, feed assimilation, growth, food conversion and survival rates of the shrimp was used to assess further the feeding stimulant properties of the substances Replicate groups of juvenile shrimp were fed semi-purified diets containing 1-5% by weight of a range of potential feeding attractants In the behavioural trial, diets containing taurine and a yeast extract were found to be significantly preferred to the control and all other diets,'However, none of the substances appeared to act as potent feeding stimulants, producing statistically similar feed intake and assimilation rates to the control diet However, taurine and an amino acid mixture designed to mimic a clam extract promoted the best performance of the attractants tested in terms of growth rate and feeding efficiency Overall, the behavioural response of the shrimp to the feeding attractants was found to show similarities to the effects of attractant supplementation of feed on subsequent ongrowing performance, but not significantly so Introduction Feeding attractants can play an important role in enhancing food detection and feeding stimulation Their role can be especially important in slow-feeding crustaceans, reducing leaching of essential water-soluble nutrients present in the diet (Deshimaru & Yone 1978; Heinen 1980) by increasing the rate of food consumption Many studies have been made of the factors involved in stimulating feeding in crustaceans, particularly with lobsters, crabs and freshwater prawns However, little is currently known about the effect of attractants on the feeding behaviour and ingestion rate of Penaeus monodon Fabricius, one of the most widely cultivated crustacean species Most of the studies on feeding attractants to crustaceans have analysed the effects of a range of concentrations of various potential attractants on behaviour, particularly with regard to their effects on the crustacean chemosensory apparatus (Carr 1978; Carr & Thompson 1983; Carr, Netherton & Mistead 1984; Carr & Derby 1986; Harpaz, Kahan, Galun & Moore 1987; Harpaz & Steiner 1987, 1990; Nakamura 1987) In addition, growth trials have been conducted with crustacean species using both commercial (Farmanfarmaian, Lauterio, Tejada, Manger, Moore & Park 1979; Murai, Sumalangkay & Pascual 1981; El Hag 1984; Costa-Pierce & Laws 1985) and semi-purified diets (Deshimaru & Yone 1978; Pascual 1980) containing various attractants Correspondence: Mr M, R, P, Briggs, Institute of Aquaculture, University of Stirling, Stirling FK9 4LA, Scotland, 613 614 R Hartati & M R P Briggs Olfactory stimulation by a variety of chemicals has been demonstrated by many authors in decapod crustaceans (Heinen 1980) Substances (usually of low molecular weight,