Max quickly decided on another, interesting change. While Tony couldn´t really speak anymore with the gag and his glued mouth, Max would like it if Tony could neigh like a real pony. For that, the surgeons opened a small part of Tony´s skull and worked on his brain. They simply removed his speech center, robbing Tony of ever speaking any human language again, not even the simplest words. Instead, the placed a part from a specially for this reason cultured horse brain there, which altered any sound made by Tony into horse sounds, therefore neighing. As Tony still couldn´t open his mouth, which would hinder him to real neigh, that cultivated part made him neigh on thought instead of speech, with the sound coming from his also switched out voice box, connected to the bit gag. Both holes were then closed again
As Tony had medium length, blond hair, which Max thought didn´t fit to a pony, it was quickly shaved away completely, leaving Tony bald. Next, Tony´s skin was coated in a special cream, which would stop any of Tony´s natural hair from growing ever again. It wouldn´t do if after some time he would return to blond hair or get any hairs on other areas of his body. It also sealed the closed holes scar free.
Then, instead of the now shaved and growth-blocked blond hair, Tony got a dark-brown mane implanted on his head like a mohawk, with continued down his neck and ended right between his shoulder blades. A covering of short, lighter brown hair was implanted all over the rest of Tony´s head and neck beside his face itself. As his ears had been fixed to the side of his head, they now lay hidden by said fur, and it would feel nice to stroke and pet his whole head. Above his ass, Tony got another implant of dark-brown hair, longer then his mane, as it gave him a nice-looking tail. And it would be easy to push it aside to free his hole for use.
The rest of Tony´s skin was covered in a second cream, a permanent protection against both sunburns and frostbites, as well as a repelling effect on any insects. An added effect was that it would make Tony´s skin stay as pale as it was. All that was important for Tony´s health, as he would stay outside most of the time, or in his stall. After all, from now on he was an outdoor animal, not a human any longer or even a house pet.
Max also decided it would be a good idea to be able to restrain his pony even more. While he could easily put a harness over him anytime he needed to, why not a more permanent solution? After all, his pony would never grow bigger, therefore the harness would never be to small afterwards.
And so, the harness he had gotten was modified for a permanent use on Tony. Each strap was cushioned to not harm him before being placed over Tony´s naked body. It even had attachments to connect a saddle on Tony´s back if needed, and connected both his bare crotch as well as his nipples, with had been pierced, to the harness. It would work as a motivation for Tony, that´s for sure. Finally, some parts of the harness were stitched to Tony´s skin, making it nearly impossible to remove it ever again, at least not without causing Tony pain.
Max was satisfied by his cute little pony, but he was thinking if he should add anything that was unique, because it wouldn´t be natural to a pony. Or should he leave Tony as he is right now, and enjoy when he wakes up later.