pairing: ChenLay
length: 2722 words
A/N: This will be very science-heavy with some specialized jargon, although most of it should be understandable in layman's terms. And there will be some descriptions that you may not be wholly comfortable with if you like mice. If you'd like to turn back now, please feel free to do so.

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Yixing looked through the animal book, taking note of the new gel images that Jongdae had printed out several days ago. He nodded approvingly, seeing a majority of the samples turn out positive for the majority of the tails he had digested the week before. “I’ll let Kyungsoo know which P30 mice to perfuse when he goes down next week.”

“Okay. Sounds good.” Jongdae grinned happily, pleased with himself. It had been his first time performing a polymerase chain reaction and he was glad that nothing had gone wrong. When Jongdae first joined the lab about a month ago, Yixing had often expressed frustration over their polymerase chain reactions not working properly, especially for genes like PTEN and Confetti. Jongdae had mostly been shadowing Yixing as he worked, with the older male explaining the mechanics behind the experiments he was running. He had learned so much in just one month, in comparison to how much he retained from his biology and chemistry lectures.

Yixing snapped the green notebook shut and shrugged off his white lab coat before picking up a small blue microcentrifuge tube rack with his free hand. “Let’s go down to the animal room now. You’ve completed your animal training right?”

Jongdae nodded, firmly answering, “Yup. I finished it two weeks ago.”

“Perfect. Can you grab a Sharpie for me?”

Jongdae immediately grabbed the closest pen he could find, and doggedly followed Yixing out of their lab space and down the hallway to the elevator. Yixing laid his ID card across the access panel before punching the button for the basement floor. After traversing five stories, they reached their destination and exited the metal elevator. Jongdae shivered from the drastic temperature change as the air conditioning system was much stronger down in the basement than it was up on the fourth floor.

“This way.” Yixing directed Jongdae to the changing room, where they needed to dress in protective clothing before entering the animal room.

It was Jongdae’s first time down in the basement, so he fumbled as he clumsily pulled on the thin yellow, papery gown. It was difficult for him to tie the limp strings around his neck and his back, and he grunted in frustration as they kept slipping from his hands.

“Need help?” Before Jongdae could react, Yixing had already stepped behind the younger male and grabbed the strings in his hands, securely tying them in a bow. “There,” he said, smiling in satisfaction once he let go of the strings.

Jongdae’s cheeks turned pink as he mumbled, “I could’ve done it myself.”

Yixing just laughed as he handed two stretchy, blue shoe covers to the younger male. “It’s no big deal. I used to have trouble with these gowns all of the time when I first came down.”

With a thin white cap, a paper face mask, and a pair of purple nitrile gloves to complete their personal protective equipment, the two left the dressing room and headed down the empty hallway to the animal room. Their shoes didn’t clack as loudly on the tile floor with the shoe covers muffling the noise. Jongdae tightly gripped the Sharpie in his hand as anticipation built up in his chest. He had never seen real, live laboratory mice before. In high school, he had dissected a dead mouse in his biology class, but that was about it.

Yixing placed his ID card on another access panel, causing a set of large double doors to open outwards automatically. The entrance led to another hallway, albeit shorter than the one they had just walked down, and the older male led Jongdae down to the end of the hall. He looked to the younger male and nudged his shoulder in the direction of the third access panel they had come across. “Do you know if your ID card works over here yet?”

Jongdae shook his head.

“Try it now. You’ll need to come down here in the future by yourself if I’m not here to check on the mice,” Yixing explained as he stepped back to make space for the younger male.

Jongdae reached into his back jeans pocket for his ID card and carefully put it on top of the access panel. The red light flashed green for a split second while beeping, signaling that lock had been temporarily disabled. “It worked!” Jongdae cheered as he pushed down on the metal door handle and entered their lab’s assigned animal room with Yixing following right behind him.

The first thing that Jongdae became aware of was the intense, foul stench of hundreds of mice that aded his nostrils. He coughed loudly into his face mask as the pungent odor grew stronger and stronger with each second. Thank god for the face mask, otherwise this concentrated scent would probably have him gagging unattractively in front of Yixing.

“It’s strong, isn’t it?” Yixing commented in an amused tone as he began inspecting the dozens of cages in the metal racks that were lined up throughout the room. “You’ll get used to it when you come down here more often.”

“God, this is gross,” Jongdae wheezed, trying to hold his breath in an unsuccessful attempt to deflect the powerful smell of the mice. As he glanced at the cage that Yixing was currently examining, he noticed that the bedding on the floor of the cage was littered with droppings and food crumbs. “Don’t these cages get cleaned?”

“They do,” Yixing answered nonchalantly, turning the cage in his hand as he looked for any newborn mice nestled within the bedding. “The Department of Animal Resources is supposed to come down once a day to feed the mice and clean the cages.”

“They aren’t doing that great of a job, are they,” Jongdae observed, wrinkling his nose with a revolted expression on his face. He couldn’t imagine having to come down here and touch all of the unpleasant, smelly bedding from the dozens of cages that were shelved on the racks. He made a mental note to avoid touching the mice and their cages if he could. All of this was way too unsanitary for him.

He quietly stood to the side with his eyes following Yixing as the older male looked through each cage that had a card with the names, Do Kyungsoo and Zhang Yixing, printed on it. There were columns and columns of cages, and Jongdae couldn’t believe that all of these mice belonged to them. Or to their lab, at least. And there were still dozens of other cages that belonged to the other teams in the lab. Jongdae wondered how much it cost to keep all of these animals alive, especially since his team alone had around thirty cages filled with almost one hundred mice.

“Jongdae?”

Yixing’s voice broke through Jongdae’s thoughts and the younger male quickly turned to face his fellow student researcher. “Yeah?”

Yixing pointed to the dark hood at the side of the room and asked while picking up a cage in his arms, “Can you turn it on and clean it for me? We have a cage with pups that needs to be genotyped. They’re just over two weeks old now.”

“Okay.” Jongdae walked over to the hood, and reached up to tap the On buttons for the fan and the light. The hood immediately began whirring as he sprayed some isopropyl onto the steel table top and wiped the liquid away with several paper towels.

As he was cleaning the hood, Yixing passed by and told the younger male, “I’m going to the other room to grab the stuff we need for the tail cutting. The cage has its card panel flipped up. Take that one and an empty cage to the hood.” And right before the door closed behind the older male, Yixing stuck his head back into the animal room and said, “Don’t forget to spray the top of the cages with alcohol!”

“Got it.” Jongdae was soon left alone and a squeamish knot formed in his stomach as he thought of having to touch a dirty, nasty cage. He first grabbed a clean one and quickly sprayed it, per Yixing’s instructions, before setting it in the hood. Now he had to deal with the other cage. Groaning loudly, Jongdae looked for the cage that Yixing had left him and gingerly slid it out of its cubby. The fetid odor suddenly grew stronger, and Jongdae felt like puking right then and there. He quickly sprayed the offending object and placed it on the table as well, shuddering as he tried to mentally erase the tainted sensation from his mind.

Yixing soon returned with a large bag filled with microcentrifuge tubes, a tube rack holding a test tube filled with ethanol, and a blue rectangular box containing several pairs of scissors. “Thanks for getting everything set up,” Yixing said as he deftly used one hand to spray everything he had brought with alcohol before placing them into the hood.

“No problem.”

Jongdae curiously watched as Yixing flipped open the animal book to a fresh page and began writing down the date of today, the cage name, the strain of the mice, and the date of birth of the mouse pups. He then removed the plastic tops and steel-barred covers of both the empty cage and the occupied cage. “C’mere,” the older male crooned as he gently grabbed a young mouse pup by the tail and dropped it into the empty cage. He did that several more times, counting under his breath as he did. “Jongdae, can you write in the animal book for me please? We have six pups that are getting their tails cut.”

Jongdae nodded as he wrote 6x on the page.

“And can you prepare six tubes for me as well?”

“I’m on it.” Jongdae grabbed a handful of microcentrifuge tubes and began labeling them, placing them into the microcentrifuge tube rack once they were ready. “Done.”

“Thank you.”

Jongdae had never witnessed the tail-cutting process before, so he quickly focused his attention on Yixing as the older male began working.  

Yixing lightly took hold of a tail with his right hand, lifting the tiny mouse pup into the air. He used his free left hand to move the steel-barred cover back onto the cage and lowered his hand so that the mouse pup could grasp onto the bars with his tiny claws. Yixing then used his left hand to pinch the back of the mouse pup’s neck and began digging his fingers into its back, trying to grab as much skin as he could without hurting the mouse pup. Once he had secured enough skin so that the mouse pup was immobile, Yixing lifted up his left hand and faced the mouse pup towards him. He tucked its tail in between his ring finger and his pinky finger, keeping the mouse pup as still as possible. “What’s the first cut?” Yixing quizzed Jongdae, having gone over the cuts with the younger male several days ago when they were digesting tails from another cage.

“Uh, single cut on the right?” Jongdae answered, recalling the list of cuts that the older male had sent him.

“Good job.” Yixing used his right hand to grab a pair of scissors and dipped them in the unscrewed test tube filled with ethanol. After wiping them on a paper towel, Yixing brought the scissors up to the mouse pup’s right ear and made a clean knick in the ear fold. The mouse pup slightly twitched, but Yixing ignored it as he moved the scissors to its tail and swiftly chopped off the tip, letting the tail end fall neatly into the first open tube on the rack. “Make sure you always clean your scissors after each cut,” Yixing said as he dipped the scissors back into the ethanol tube while Jongdae lifted up the original cage cover so the older male could drop the mouse pup back in. “And that’s all there is to it.”

Jongdae was amazed. It looked so easy and effortless when Yixing did it. With the same dexterity and skill, the older male continued tagging the next four mice and snipping off the ends of their tails while Jongdae watched with wide eyes.

“Do you want to try the last one?” Yixing asked as he cleaned his scissors for the fifth time.

“I don’t know…” Even if he was okay with watching them, actually touching them was a whole other story.

“You’ll need to practice for when I’m not here,” Yixing reminded the apprehensive male. “And Kyungsoo won’t always be around to cut tails either, so you need to get comfortable with touching the mice.” The older male sent Jongdae a reassuring smile, saying, “You don’t need to be afraid.”

“I’m not afraid of them,” Jongdae clarified as he cautiously stepped to the hood. “They just kind of gross me out, since that cage is filthy.”

Yixing chuckled at Jongdae’s disgusted expression and obvious discomfort with the germy mice. “Don’t worry. We’ll disinfect ourselves when we’re done. But for now, you need to get used to touching them, dirty or not.”

Jongdae grimaced as he slowly reached for the last mouse pup, trying to mimic Yixing’s earlier movements. The mouse pup squirmed in his hand and he quickly brought it up to the steel-barred cover, where it desperately clutched the bars for dear life. As Jongdae began grabbing the neck skin, he felt like he was about to snap the poor mouse pup’s neck in half. But just as he was about to lift up the mouse, Yixing’s command stopped him in his tracks.

“No, press harder.”

“But I feel like I’m going to break it,” Jongdae protested, trying to keep the mouse pup from wriggling in his left hand.

“You’re not. Trust me,” Yixing replied, staring at Jongdae’s hold on the mouse pup. “These guys are a lot tougher than you think. Just grab as much skin as you can. Go deep. Otherwise, you might get bit.”

“Okay…” He certainly didn’t want anything to bite him. That was like asking for a disease to infect him. So Jongdae reached for more skin and tightened his grip on the mouse pup. He wasn’t even thinking about the sanitary aspects of touching the animal anymore. He just felt bad that he was possibly causing it pain. But when Yixing kept egging him to grab more skin, he up his sympathy and firmly grabbed its neck skin.

“Good. Now turn it around.”

Jongdae continued following Yixing’s instructions and managed to successfully tuck the motionless mouse pup’s tail in between the fingers of his left hand. He picked up the hole-punch clippers with his right hand, and carefully punched one hole in both ears to tag it as the sixth mouse pup. His hand slightly shook, but Yixing grabbed his elbow in an effort to steady it. Jongdae smiled gratefully at the older male before reaching for the scissors and t off the end of the mouse pup’s tail.

“Great job!” Yixing beamed, clapping his hands together. “You can drop it back in the cage now.”

The younger male hastily lifted the cage cover and let go of the little mouse pup, returning it back to its family who were all scurrying around the cage. “Are we done now?”

“We are. Time to get these digested,” Yixing said as he hoisted the cages in his arms and placed them where they belonged. “Do we have any Solution A ready?”

“Yeah, I saw Sehun making some yesterday, so it should be sitting in the fridge,” Jongdae responded as he wiped down the table top with isopropyl before shutting off the fan and the hood light.

“Awesome. That wasn’t too bad, was it?”

“I guess.” Jongdae wouldn’t say that he enjoyed doing this. But it wasn’t horrible enough for him to want to swear off ever working with laboratory mice again. Nevertheless, all he wanted right now to was cleanse himself because he felt so grimy and gross after being in that animal room for so long.

“We’ll come back down and practice some more until you’re completely comfortable with tail cutting. I might just end up having you being our resident tail-cutter from now on,” Yixing proposed, laughing as Jongdae scowled at him.

“You’re hilarious, Yixing.”

♈♈♈