Thank you both for your help.
I would like to update
I can not find Flagyl or Fish Zole, the ornament birds medication is active ingredient is Oxytetracycline Hydrochloride. Might be we have different medication in Australia?
He could have canker or wet fowl pox. My head is so dense with worry that I can not clearly see much of this at the moment. I have fear now that whatever he is having will be showing on the rest of my flock in a week or so time.
Yesterday evening I gave my roo 30ml of Mavlab Oxymav B, crush garlic and VetRx on his face and nose.
By late afternoon yesterday, he was laying on the floor, head down and mouth opened.
This morning he stretched his wings, groomed himself, crowed and crowed with many broken sound. He did eat a bit, still have some issues with swallowing, crop emptied, no mucus in his mouth.
Head held steady for a bit, then dropped again half way. It seems that he is improving a little bit.
This morning I gave him 15ml of Mavlab Oxymav B, crush garlic and VetRx. Then put him back to his bed with classical music on the radio. He is crowing loudly, his voice can break the sky sometimes.
For the rest of today, he will have 15ml of Mavlab Oxymav B every 3 hours.
We are having pouring rain here, so he has to be confined all day. I hope he is continues to improve from here.