Utilization and excretion of organic nitrogen by the silverfish, Ctenolepisma lineata

Abstract

Conversion efficiencies of organic nitrogen to live weight have been determined for the silverfish, Ctenolepisma lineata. These efficiencies vary from 0·014 to 0·13 mg N/mg live weight between animals and vary similarly within the same animal depending on the diet. The rate of weight gain by animals feeding on a complete diet ranged from 0·25 to 0·67 mg live weight per week. The silverfish can also live for extended periods on a diet of cellulose alone but requires a source of organic nitrogen for growth and other vital processes. Conservation of nitrogen seems to be accomplished by an inherent low turnover of tissue nitrogen when the animal is metabolizing carbohydrates. C. lineata may lose from 8 to 20 per cent of its total body nitrogen before expiring.