Male rat - Pleasuring himself?

Question
I am a early biologist, I am in the study in RATS. And I was just seeing a male
rat (4-6 months) and I already know that, that is when they hit "puberty" so to
speak. And their testosterone levels are rising ready to mate, but what I didn't
know was that -I met one male, and he 'pleasured' himself (if you catch my
drift)  by sucking his penis and lunging his hips forwards in a pattern almost.
When I stopped him, he would "hump" my hand. His penis would come out
fully, and try to literally mate me. I have never witnessed such strange
behavior in all my 13 years of biology work with rats. All I do is study the
behavior (incase you thought I was dissecting the little fellow's! No...) Well
anyway, I would love to know what this meant or what he was doing since I
am ever so interested.
Thank you Sandra for your time and effort: A.K.  

Answer
Hi

To be totally honest, rats hit puberty alot younger than 4 to 6 months of age.  

The age of sexually maturity starts right around 6 weeks and this is when mating begins, not at the rise of testosterone levels at 4 to 6 months.  Social maturity usually begins around 6 months, which is often when the pecking order begins to take place. The rising testosterone levels bring on aggression more than the urge to mate. This is also the age when any issues with aggression over who the alpha male is going to be will take place and often the age when the intact male rat may find himself on the table of a Veterinary surgeon getting ready for a neuter if he doesnt know how to handle his soaring testosterone levels and is the center of most quarrels in the mischief.

As for masturbation, this should not come as any surprise. Most animals do masturbate, if not with their hands, they use their mouth. It may be the first time you have seen this happen but it certainly isnt the first time it has happened.

Next time, draw the curtains and leave him be. ;)