those black dots are call static mites or hair mites..
normal look like this:

up close they look like this

they move when u drop some drops of vinegar on them.

they cause minor itch, not very serious... but u can give them revolution or advatage , solve ur problem in 3 weeks times

get the one for cats... for dog 1 too strong

OMG, my Piggies got the hair mites too. When I Close see it the mites were moving up and down. Yucks.. I used the guinea pig shampoo to shower them with warmth water... then rub their fur. After finishing showered, I then let them ran around. Finally I put some baby powder for them and guess what ? they look happy. I did use vinegar with towel to clean around the cage, changed new bedding. Hope this fine after what I've done so far to get rid of the mites.

topical, only buy the one for cats only.

ur pigs weight in kg / 10 = dosage in ml
example xxx piggy is 300g
0.3 /10 = 0.03ml of revolution on the the skin on the shoulder bone..done.. normally 2 to 3 application should do the job.. wait 2-3 week b4 each re-application
soli for my previous post: is advocate not advantage for cats... get the one for less than 4kg one...
packaging about similar to this..
dosage is 1 drops each application.

My totty died this morning
I dont know why. He act very normal. No wet chin, eating well and all. Just last night i realized he didnt eat that much. RIP Totty. Mommy will miss you

Just remember to feed it veges and Alfafa Hay or u can find Alfafa based pellets like Oxbow Cavy Performance those kind =) And no, Hay is always better than grass! In pregnant case is Alfafa Hay ! Ur grass get from where de ya? Make sure its  Grass occasionally is okay hehe.
Well I know of a breeder from banting...or u can find here https://www.facebook.com/groups/220414517990586/ this is Malaysia's biggest cavy fan page! Alot of breeders..owners...and many more..u can find nice peruvian's there =)
Lolsz Chubbyagel...ur guinea pig is what type? If based on ur profile pic, it shud be American short hair? Or in our case...Malaysian short hair =.=" Malaysian breeds are like this de..the gp body size small small..especially short hairs...cause they mix + inbreeding + macam macam factor sampai gao gao...huhu.... And no, vit c doesnt affect the weight i think...its for their health only =) If appetite still okay, den shud be no problem. Hmm...apartment ah? Where got space put only lor...haha XD if got empty room puyt there better! Like kaoru i think, she put in empty room, den can let GP roam free in the room...so nice hehe XD