Abstract: A prepared cat food has chicken meat and mouse meat, the chicken meat in at least ten times the mass of the mouse meat, vitamin supplements, and one or more mineral ingredients. The mouse meat in a substantially lesser mass than the chicken meat induces the cat to consume a greater volume of the prepared food than the cat would consume without the presence of the mouse meat, thereby supplying the cat with a greater volume of chicken meat, vitamin supplements and mineral ingredients than cat would consume in a product without the mouse meat.

Abstract: A cat food has chicken meat and mouse meat, vitamin supplements, and one or more mineral ingredients. The mouse meat may be less than ten percent by weight of the total weight of meat.

Abstract: A system for detecting presence of an organism having an enzyme in a sample, comprising: a cartridge for containing the sample and a substrate such that the enzyme can react with the substrate to produce a biological molecule; a partitioning element mounted in a recess in a base of the cartridge, the partitioning element allowing partitioning of the biological molecule thereinto; a light source for irradiating the biological molecule partitioned into the partitioning element; and, a detector for detecting fluorescence of the biological molecule partitioned into the partitioning element, the detected fluorescence being indicative of presence of the organism in the sample; wherein the light source is in a raised cartridge mount of the system that mates with the recess in the base of the cartridge. Also provided is a method for calibrating said system and quality control cartridges for use in same.