injury or disease?? please help!

[Kapokkie]

I have recently adopted two beautiful but neglected bantam hens from someone that was too old to look after them anymore. Their legs and feet are stiff and swollen and look dirty.
Their previous owner said that it was an injury from tripping over some baling twine, but I am worried that they may have a disease that could be passed on to my darling rooster. One of them is still very young and has recently hatched her first offspring. She is very skinny and her head hangs down sometimes and her comb is very small. Her vent looks a bit poopy. The older one hardly ever uses her left leg. Her comb has some rough black markings, which the owner put down to fighting/pecking.
I was told to dip their feet in used motor oil, but I don’t trust the idea. I would love to keep them and nurse them, but not at the risk of the other poultry. Please help!!

 

[Kat'sChicks]

First, let me say

and thank you for taking those birds in!
I'm not an expert like many on the site, but I'll make a suggestion or two....
Used motor oil???? Not on my chickens.

I'd suggest taking pictures before you clean those legs and after, then posting them so everyone can see what type of marks they are to help diagnose. Might be a good idea to include a pic of the entire bird(s) as well. Dirt can hide a lot of things and make something simple look really bad too. There's a "sticky" post on here that has a list of questions to answer to help with diagnosis also. Make sure you look them over really well, including under wings and make note of anything that doesn't look right. Where are you keeping them for now?
I'd suggest giving them Poly-Vi-Sol WITHOUT iron baby vitamins in their water and maybe a little plain yogurt to help with good bacteria and some calcium too.
Other than those few things, watch how your new chickens behave and be patient; it may be a little while until someone else gives feedback.
Good luck, I'll watch patiently......