You're not sure how much time passes as the two machines thrum across your gut, but you come to when the leader begins to shout.
"Hey, who did this with Martin's clothes?!"
You don't know who Martin is, but there was now a cow standing where the fat kid used to be, and the tattered remains of his clothes were sitting on the floor. Looked like all the other cows, if a little small. Still aware of your surroundings, you start looking around.
The kid that was chugging milk has also disappeared, and the one toppling canisters found a pink medicine ball that he was rolling around. The boy dancing on the conveyor seems to have gotten tired and was sitting. The two kids that had that milk-fight were now trying to figure out how to make what looked like an automated cow-wash clean them, as they'd hooked a cow into the start and were pushing buttons. Your two impromptu friends were still as happy as ever.
The machines throughout the barn started to whir up, and you returned your gaze to the kids at the washing area. They were apparently successful as the cow started getting slowly pulled through the tunnel, but they must've turned on more than that. The hands were starting to move and it looks like they also closed all entryways into this barn. They were too far to hear, but they seemed to jump around excited as water spilled from the other side, then they both stepped into the thing.
A sudden wave of heat pressed into your gut as the milkers made new noises. It was a wonderful feeling, causing you to briefly fall back into that near-sleeping state, but a scream brought you back. The boy that had the chest-mounted attachment continued screaming, and it wasn't too surprising as he now had a huge udder dangling off his chest. "Oh my god! What is this?!" He frantically tried to pull the attachment off him, but he gasped and stopped just as quick as he'd started. He looked like he was struggling to breathe, and he leaned forward. "Someone, help me! Get this thing off me!"
You looked to the other kid, and realized he also had a growing udder cupped in his lap. However, he didn't seem phased, nor did he even open his eyes. Looking down, you realize that you've also got a sea of pink as each leg is pinned by an udder. You carefully pat the twin masses, and are shocked by how sensitive it feels. You try to move, but the combined weight is just too great. "Hey, wake up! We need your help!" The meditating kid seems to ignore you, or he's catatonic, so you look to get someone else to help.
The one at the canisters seems to be stuck on the pink ball, if his frantic flailing in place is any indication. As you stare at the strange display, his body begins to rapidly expand as the ball shrinks until it looks like he's got a huge package, then fur begins to sprout and bones begin to reshape until he's a dairy cow with a weirdly large udder.
The two kids that went into the wash haven't come out, but the three cows they put through first have. You chastise yourself, the wash probably made them into cows.
The machine had captured the boy on the conveyor belt quickly, and whatever was in those syringes had made quick work of his body. The only marker of his previous humanity was his strange struggling as a cow and the rapidly-thinning hair that looked like a wig on the beast.
All that was left was the leader, who was panicking because his hand had turned into a hoof. You decide he's still your best bet, so you call out to him for help. Instead, he runs over to one of the doors and starts slamming on it, begging to be let out. He never saw the syringe coming, and as the syringe combined with whatever was in his system before, his begging quickly turned to moos.
This left you with only your circle of 'friends.' Before you could figure out a solution, the attachment paused on the meditative kid, then a new color of fluid entered.
This seemed to jolt him awake. "What? Why did it stop feeling- What the hell is happening to moo-" The transformation started with his rear, tearing his pants apart as it exploded with size. It rapidly expanded up his body, leaving him shortly as a human-headed cow, before the chemical wiped whatever was left of his humanity, leaving a confused-looking cow sitting strangely upright.
The other boy could see the writing on the wall. "I don't want to be a cow!"
You had to stay calm. "Me neither. Can you remove my attachments, so I can remove yours? I can barely move with two of them pumping."
He nodded nervously, then started to crawl forward, but his attachment halted just like the last kid's had done. Panic filled his eyes as the same colored fluid started to flow into his chest. "I don't want to...don't want...don't..." Unlike before, the chest-mounted kid's head was hit almost instantly. His arms turned into cow legs, but they looked backwards. His head began to soften, then deflate as his neck seemed to lengthen. Soon, his features softened into nonexistence while a new mass formed in his pants. In a matter of moments, you'd gone from conversing with the kid to looking at a cow's butt, as a new head ripped through the pants. The only indication of this cow being backwards was the strangely red tuft of hair for its tail, which exactly matched the kid's original hair color. Unlike the first kid, this cow head seemed to be 100% real cow, as it was calm and milling about, where the rest of the kids-turned-cow the machine hadn't yet caught were stumbling about the room in a panic.
With no one left to help you, you resign yourself to your inevitable fate.