| Sumario: | The biogenic amines are biologically active compounds synthesized from amino acids. Feedbornebiogenic amines are most commonly synthesized by spoilage microorganisms and are usuallyconsidered to be potential toxins. There has also been interest in aquacultural circles in the potentialchemoattractant properties of these compounds. A subgroup of the biogenic amines are the mammalianpolyamines: putrescine, spermidine and spermine. The polyamines are cationic compounds synthesized frommethionine and ornithine in short, highly regulated pathways. The polyamines are anabolic compounds withhormone-like properties. It has been proposed that exogenous dietary polyamines may play an important rolein promoting growth and maintaining health. A series of experiments have been conducted with chicks fed acrystalline amino acid-based purified diet. Chicks were fed dietary supplements of putrescine, spermidine,spermine and cadaverine. Although all these compounds promoted intestinal tract development, onlyputrescine promoted whole body growth. Dietary putrescine was also shown to overcome the toxicity of rawlegumes when added to chick diets. Putrescine was also shown to increase intestinal development and wholebody growth of turkey poults fed a practical diet. Laying hens fed diets supplemented with putrescine had adecrease in egg shell deformations and increased egg shell thickness. In experiments with blue shrimp(Litopenaeus stylirostris), shrimp diets were supplemented separately with cadaverine, histamine, putrescine,spermidine and spermine. Spermine was observed to have the greatest growth promoting potential in shrimp.Spermine was added to diets at 0, 500, 1100, 2300, 3400 and 4600 mg kg-1. Significant quadratic responseswere seen in final weight, weight gain and feed conversion ratio. Whole body polyamine concentrations werealso altered by diet while trends were seen in concentrations of polyamines in the heptopancreas. It wasconcluded that supplemental dietary spermine can promote the growth of blue shrimp and that this effect islikely due to altered polyamine metabolism. Biogenic amines should not always be considered as potentialtoxicants and chemoattractants, therefore, but can also be considered to be non-hormonal growth promotants.
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