-196 C.A bull produces an average of 480 doses per approved ejaculation. A popular bull can supply up to 300,000 doses in its lifetime. Each such dose is collected in a straw. The straws are stored in liquid nitrogen at a temperature of -196 degrees Celsius. Every beaker holds 3000 straws. Altogether there are some 600,000 straws in a container. The colour, together with a code, name and date, makes each straw unique.