Metabolic cages provide accurate measurement of rodent waste materials (urine and feces).  Each cage consists of a trough, receptacle, miniture scale, scale pan and water bottle.  The trough, shaped as an open box, is made of smooth gnaw-proof plastics. It glides into a receptacle made of stainless steel, fastened to its scale-pan, which senses the load of the pellet food and hence monitors the quantity and frequency of food uptake. The crumbs the animal produces are collected in the front compartment, for a precise evaluation of the food consumption.  The water bottles are provided with a spout and rest on a support stud fastened to the scale pan for monitoring quantity and frequency of water uptake. Provision is made to collect any dripping for a more precise water consumption evaluation.