Does the major ritual impurity requiring ghusl (full ablution) persist after a vasectomy performed for health reasons, or does it become a minor ritual impurity, given that the fluid no longer contains sperm?

You are not required to perform ghusl (definition) (ritual bath) for janabah (definition) (state of ritual impurity) due to the discharge of the aforementioned fluid after the surgery, because its exit is due to illness and not desire. Furthermore, it is not semen; rather, it originates from the prostate area. It is closer to madhy (pre-seminal fluid) and necessitates istinja (definition)' (washing the private parts) and washing the penis. However, if intercourse occurred with penetration, then ghusl is obligatory.