Hi Alex,
Stop the "gruel" of canned food !!!! 3 weeks is too young for that ! The solid food is not digested properly, because she still has the intestinal bacteria to only digest "Milk", because her intestines are not mature enough yet. Instead, feed her all the KMR, she wants, but add extra water to it for 3-5 days. (Constipation means she CAN'T poop. She's not constipated !) If you're using the powdered KMR, mix one scoop KMR with "3" scoops water (instead of 2)! If you're using the canned liquid KMR, add about a third extra water. She's probably dehydrated, and the extra water will help thin down her poop, so that it's smaller and more comfortable for her to go. Also, put a small plastic container in with her, with just Regular, Clay NON-clumping litter. She's probably old enough to not need "stimulating" any more. I use a square or rectangular plastic storage bowl, so it's low enough for her to climb into. Never use "Scoopable" litter, as babies tend to eat it and it turns to cement in their tummies and intestines! Only UN-scoopable ! You could also use UN-flavored Pedialyte to add to her formula, instead of the water. She shouldn't start solid food till 5-6 weeks old.
Just saw you're giving 5cc LR ... Injecting under her skin ? You could use that in her formula, instead of extra water or Pedialyte. After a day or two, her system should straighten out pretty good. If not, she may have an intestinal infection, or coccidia, or something along those lines.??? Have you given her worm meds yet ? You can bet they're born with them, and it's ALWAYS best to give them Pyrantel Pamoate as soon as you get them home, (for roundworms and hookworms) then again in 10 days ! They are never too young for this ! And when they're about 4 weeks old make sure you give her Praziquantel too (for tapeworms)!
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