Duck feet turning black

[Brenda Shumate]

My female duck's feet are turning black and her honk sounds like she's a bit horse. She is walking fine, eating fine, acting fine, except I think she's not cleaning herself as good as she used to. One of my males feet have begun to turn as well. Its not frost bite, as it is August in northern Calif. and it's been slowing coming on for a couple of months. Any ideas would be greatly appreciated. I change their pond water every day, so they have clean water. They eat good food. Although they love dry cat food. I feed several cats outside; the ducks to eat the dry cat food. Could this be a problem?
Thanks in advance for your help.

 

[chickens really]

Possibly too much Cat food ?...I dont think so?

Are they over weight?...Lack of circulation can cause dead tissue...

 

[chickens really]

@casportpony

 

[Brenda Shumate]

Possibly too much Cat food ?...I dont think so?

Are they over weight?...Lack of circulation can cause dead tissue...

No, they are not over weight. Her 'honk' has improved, thank goodness. But her feet are still black and her bill as well now. She is still walking fine, doesn't seem to have any problems except her feet and bill has turned black. I have been keeping most of the cat food away from her and her 'honk' went back to normal. No idea if it's because of no cat food or not. She still lays eggs as well, just not as often. I think she's getting older and that may be why not as many eggs. Any ideas? Really appreciate any help I can get. She's such a sweet girl, I'd hate to lose her.