I havea 4 year old neutered female cat who is otherwise  healthy.  On
Sunday morning she was caught under my kitchen table starting to try
and eat a blackbird.   I removed the bird.  Later in the day  she
seemed a little lacklustre  and on Monday morning she did not go out
as she normally would when I open the door (both my cats go and patrol
the gardens  first thing)    instead  she lay on the bed and I
returned and she stayed with me for a while.  Then she went to her
tray and seemed to produce some pretty soft and messy faeces.  She
seemed very lifeless  and it was very wet and messy around her anus.
I tried to wipe it with some kitchen towel but she was not
enthusiastic and would not let me.  She tried to clean herself up by
licking it  (yuk)
She spent the day lazing about and sleeping and ate almost nothing.
But in the evening she had made a small bit of progress.  On tuesday
morning she wentoutside for some time, ansd was brighter, and indeed
very keen to eat.   Although she was brighter she did not appear to be
much interested in grooming.  I decided to take her to a vet.  Near me
is a practice that is very basic and charges a small fee and have a
walk in hour  (no appointment needed)    I  took her there and was
first in (thus avoiding a long wait with barking dog patients)

The vet examined and said he could find no abnormality  and he said he
would gu=ive her his pick me up.  I asked  what it wass and he said it
would be vitamins  and antibiotics.   I refused the antibiotics as on
a previous occasion  the intramuscular injection caused my other cat
not to be able to walk properly for over a day
and because it was far from clear after only a 24 hr or so illness
that infection was evident.   Nonetheless  the vitamin injection
seemed  also to be applied the painful intramuscular way  (large
needle  into front shoulder area.  )    The  cat screamed, and  when I
got her home rapidly  developed  shaking and trembling and staggering
about  and clingy.  After half an hour she was more competant on her
feet and steadily ambled to the bedroom where  she jumpted onto the
bed and curled up for a sleep.  I decided after some frantic  phone
calls not to take her  back to the vet  (or  the other vets I use)
and instead let her rest  and closely observe her.  In the evening she
joined us in the living room and rested  quietly, then spent the night
on my bed with me, as usual.

I think that vet hates cats  and is disrespectful of dogs.  Other
people have told me that he has been brutal towards  clients
animals.  Thats another  story but I thought his injection came close
to killing my cat and its only  since that trauma  that the tiny red
blood  spots/mucus appeared in the litter tray

On Wednesday morning she was keen to go out and more normal,  ate
plenty etc.  But in the afternoon I noticed  that on the litter tray
surface was some muvus  and blood  (the very tiniest amount.
Probably not enough to paint a  fingernail.   And  about 3  hours
later I observed her do it again  This time a little bit of faeces in
which was a tiny bit of blood and mucus.

Then at bedtime she left  the bed used  the litter tray and  this
morning I could another  small example.   So several hours seem to be
between attempts to defecate

This morning  (Thursday)   she has  gone out,  ate  etc  but I  think
she is lethargic  and quiet  (as  throughout most of the last days)
So it seemed to have started dramatically on Monday  and all her
elimination until wednesday 5pm seemed just softer than normal,  now
there are tiny bright red spots/flecks of blood

I observe also a tendency to strain a bit  at the litterbox    She has
like a spasm does not cry out but it looks as though he colon thinks
there is something ti eliminate but there isnt.

So now  the dilemma.  A trip to the vets today ?    A bright eyed
otherwise lacklustre creature  that is eating.drinking and spending
some time outside as well as not hiding away inside.  Should I rush to
a vet ?     It will involve a  real struggle to get her into the
carrier   (can take 5 minutes  of fighting )    Or  shoukld I watch
and wait for another  24/48 hours.

She seemed keen for me to lie  down on the bed  and snuggle on my
chest. Last night for 2 hours in mid  evening.  I think that might be
that any soreness from colitus may be soothed by the warmth.  Like
putting a hot  water bottle on the tummy when poorly

Both my  cats are insured, and so cost is not an issue

My reading indicates  the greatest liklihood  is  colitis, unlikely to
be parasite related in the adult  cat.  More likely other causes./

I really wonder about that dead  bird.

Any advice would be appreciated