A laboratory study on the 4^th instar
larvae of cotton leaf worm. , Spodoptera littoralis (Biosd.) was carried
out to detect and quantify some nitrogenous components related to protein
metabolism and also to evaluate the secondary effect of the bioinsecticide;
Spinetoram. It is the first time to detect albumin and creatinine in this
species. Acute and latent effects using three concentrations revealed that the
excretory product; uric acid was significantly reduced 6-days post treatment by
the highest concentration (6.67ppm). It was 14.15 and 10.94 ug/mg protein for
control and treated larvae, respectively. Creatinine
which is an end product of phosphocreatine that acts as energy storage in
skeletal muscles and other tissues is significantly increased on the 4^th
day post larval treatment. The insecticidal concentration range was not
critical in most cases. Albumin was significantly reduced at the 4^th
day post treatment and this reduction extended significantly to 6^th
day for all concentrations.Glutamic oxaloacetic transaminase (GOT) and glutamic
pyruvic transaminases (GPT) titres were significantly reduced as compared to
control at the same time, the situation that reflects the importance of
Spinetoram latent effect.  Spinetoram
could affect protein metabolism of the cotton leaf worm for energy reserves,
metabolic enzymes, protein quality and excretory metabolism point of view