Injured little duckling, trouble walking

[Miss Red]

I have a just-over-a-week old Giant Peking duckling that started walking funny on Friday. We thought he had pulled his leg in one of his out door trips, or maybe just stepped on something.

Saturday I noticed he wasn't as willing to walk, and his swimming wasn't the same. He mostly would just sit in one spot and paddle his legs frantically.

Today I noticed that he has hardly managed to get up, and when he does he can only take a few steps at a time before he falls over or lays back down. I picked him up and very carefully flipped him on his back, it seems his legs rotate outwards at the hips. Do ducks get hip displaysia[sp]? Or could it be something else, like splay leg? I will post pictures of his legs when he does it again. Right now he's laying down under the light resting and drying off from a good swim. The other duckling walks fine, runs fine, swims fine.

Leading Factors:
-- Their first trip outside was Wednesday, none of the chicks acted wierd or were exposed to any poisonous plants.
-- They were, however, in a wire dog crate with the plastic bottom taken out. There were no obviously raised points in a the cage off the ground, but could he have tangled a leg up in it? Not sure.
-- His [knee?] joints are VERY swollen. So are those around his feet.
-- Arthritis at a week old?

----Pictures will be posted soon.----

 

[Miss Red]

These show how his hips rotate outwards, how he sits low on his butt, and his swollen joints [although the picture doesn't make them look as swollen as they are]

ETA: I have been doing a lot of 'water therapy' with him since the symptoms started. They seem to get worse the longer he is OUT of water. He hasn't been swimming in about two hours and is starting to go downhill again. Any ideas?

 

[Miss Red]

Still no answers, still searching for one elsewhere, but I figured I would post an update on Chong just in case anyone is stalking this thread.

Today the chicks and ducks spent 7 hours outside. Chong seemed to be walking a little better when he came back in, although he did look just as sore and was still falling down on his stomach after a few steps. BUT it didn't look as painful. Once they were placed back in the brooder he placed his fat butt under the lamp and hasn't got up since. That was an hour ago.

Again, can ducks get hip displaysia? I'm beginning to think that's what it is.