Why is my cat's rear end bloody with pus and a sour smell?

I don't see anything outwardly abnormal from these photos. The blood is usually from straining to defecate but it could also be from rectal polyps, issues with the anal glands, inflammatory bowel disease or intestinal parasites. It is not an emergency but I suggest you have her examined by your vet in the next couple days.

It could be that Booty had impacted anal sacs, and they have now ruptured. That would cause her to bleed from her anus, and drag her bottom on the ground. It could also be that he suffered trauma to his anus, like from a foreign body, or he could be suffering from intestinal worms. I would take him into the vet first thing in the morning. The vet can determine what is causing his anus to bleed, and can treat it from there.

Poor girl. This does appear to be a possible anal gland abscess rupture. She will need antibiotics from your vet and anti-inflammatory medicaiton to get this to heal well. Most cats won’t let you flush this unless they are mildly sedated or restrained by a trained professional; therefore, I would not advise you trying to clean this area yourself. It’s best to take Rose in to your local vet in the morning to get this taken care of. She will be in discomfort until then, but these aren’t typically life threatening. I hope Rose gets this to heal soon. Best wishes and take care.

She may have an anal sac abscess, or she could have a little bit of colitis and she just hasn’t had a bowel movement for you to see the full effect of what is going on. Look all around her rear end for any wounds . If it continues then she should be evaluated by a veterinarian soon. Best of luck and I hope she improves soon. Thank you for using Pet Coach.

With so many symptoms I recommend a vet check as soon as possible - it sounds like he has developed a severe diarrhea/colitis and fecal incontinence and he requires urgent treatment. In the meantime offer a bland diet of boiled chicken or fish and a probiotic supplement such as fortiflora

She may have an infected anal sac or a little growth. You should have this examined by a veterinarian. If it is an impacted anal sac, it can easily be emptied. If it is a growth, it may have to be removed.

It looks like it could be coming from Cheese's anal sacs. It may be they are infected. I'd take her into the vet first thing Monday morning to have this examined, diagnosed, and treated. Best of luck.