Thanks for your reply Cass. We don't have any grass at this time of year...it is all snow! At first I was thinking it might be the grass since that was back in mid-summer when the issues started, but now it just can't be since we have had several months of no grass now. For their beds I was using Tide Free & Clear, then I switched to simply using washing soda and Borax (a cup of each in a large load). In the last couple loads I have added a few drops of Tea Tree Oil to the rinse water to help with smells since the washing soda and Borax wasn't doing the trick. These changes don't seem to have made any difference.
Roxy still scoots her butt now and then, but she isn't stinking of anal glands anymore either, so that's good news as well. We'll see what the diet change does for this...
So far, the change in food hasn't caused any further irritation. Roxy just has some mild irritation between her toes which has been persistent since before I made the food changes, so now I'm pretty sure the issue isn't the food either like I was suspecting a few months ago. She has now been fully changed over to Acana Wild Prairie (which I thought she had a reaction to last fall) for four days. I started the switch on Feb 7th. I'm still giving her about 3 tbsp of plain yogurt twice a day. I think all yogurt has live cultures in it, but I made sure to choose one that states live probiotic cultures right on the package.
Roxy - Feb 2005 - 75 lb American Staffordshire Terrier (adopted Jul 2011)
Peewee - Jan 2006 - 8 lb Chihuahua (adopted May 2009)
Myka - Nov 1998 to Jan 2010 - 85 lb American Pit Bull Terrier cross
Lacy - Sept 1992 to July 2003 - 18 lb Reg Shetland Sheepdog