 They begin to dribble urine, initially as discrete drops and later in a regular stream.These manifestations of musth last from a few days to months, depending on the age and condition of the bull.When a bull has been urinating for a long time, the proximal part of the penis and the distal end of the sheath show a greenish coloration, termed the 'green penis syndrome' by Joyce Poole and Cynthia Moss.