Gander weak, not eating, cannot stand

[GEESES Peanut Butter Cup]

Having a gander of approximately 4-5 months old. It had a toenail broken earlier this week and had blood lost. The blood stopped eventually, but as it sometimes raises its foot with the broken nail, I think it hurts to him.

Today, the gander could walk earlier, but since a few hours ago, its behavior has been unusual. It was standing, without ever sitting, near the water/feed area, drinking water but not eating the feed, for several hours. Giving it oats, which are his favorite, didn't lead him to eat - lettuce and watermelon, either. Then it didn't stand but instead cannot stand, his legs weak. I put some Sav-A-Chick water, but he hasn't drunken any.

We also noticed its butt not clean, which is unusual, too. When it was still able to stand, it kept shaking its butt/tail.

Is there any emergency thing I can do to prevent him from dying?

Update:
It looks even weaker now. Laying on the floor, with wings drooping. Still hasn't drunk anything.

 

[Miss Lydia]

Any chance you can take this young on to a vet?

 

[Eggcessive]

You would be better off posting on the geese forum here:
https://www.backyardchickens.com/forums/geese.47/

I would offer some Poultry NutriDrench, electrolytes, or Gatorade with a small scoop or cup to the beak in the meantime. Could he be dehydrated or suffering from heatstroke? If you can consult a vet, that would be best.

 

[GEESES Peanut Butter Cup]

I had another thread on the geese forum, but it was merged into this one (not by me).

Thanks to all who tried to help. Unfortunately, the goose died within hours after I created this thread. It was night time when all this happened, and I wasn't able to find a vet available then.

I'll post more details later. Here's a short version of the necropsy result: Dr. Lintner of the Avian Medical Center at Lake Oswego, OR, US did the necropsy and told me he died from a rare case of a blood clot that blocked blood supply to critical part of the body, which caused his death. She said it's not related to the broken toenail and the goose was otherwise healthy.

I'll ask her more questions when she's available.

 

[Eggcessive]

Sorry for your loss. It was unfortunate, but it doesn’t seem like there was anything to do for him.