Twoiso-nitrogenousandiso-lipidicdietswereformulated (Table1)accordingtotheknownrequirementsfortilapia[26]. P.acidilacticiMA18/5M(Bactocell,LallemandInc.,Canada)was culturedandthedietswerepreparedasdescribedpreviously[8]to produce2mmpellets.Thebacterialcellsweredilutedtothe desiredconcentrationbasedonacalibrationcurve(CFUml1vs OD590)toachievethemanufacturer’srecommendeddoseinthe f inalpellet(106CFUg1).Washedcellswerethenaddeddropwise intothebasalmixturewhichwasthoroughlyhomogenised,with theadditionfishoil,cornoilandwarmwateruntiladoughyconsistencywasachieved.Thiswasthethencoldpressextrudedusing