When you have a problem with an aggressive cat in the house, the situation can soon turn from tricky to unpleasant for the whole family.  A concerned reader approached me with the following problem in her home.

"Dear dr. Adel,
I am at my wits end with 2 of my female cats.
The one is 10 years (Jingles) of age and the other (Mia) is about 3 years old.
Jingles was "attacked" (hissing, spitting and hit-and-run swats) by my daughters cat Mia (who has a feral streak in her as she was a feral kitten) when my daughter moved in with us.
The two of them are always at each other. I have put my Jingles on the hormone collar, I have a diffuser in our room during the night only and this has been for about 1 week so far. The collar seems to have calmed Jingles down a little, but now Mia has taken over the upper hand and is deliberately attacking Jingles.
Poor old Jingles has had enough of all of this and has started to hiss and spit at everything that moves - even if nobody has done anything.

• Besides putting Mia on the collar as well (breaking my bank here) what do I do? and
• is one month of them both being on the collars enough?

I dont want to put any of my animals to sleep over an issue like this. Even though 2 of the 5 cats in our house belong to my daughter...they are all my babies. There has to be a solution. Please advise urgently.
Val Grobler
East London"

Dear Val,
Inter cat aggression
To start evaluating inter cat aggression it is important to identify any patterns or triggers. Ask yourself the following questions:
• Is the aggression associated with certain areas in the house/ specific rooms/ approximation to food?
• Did some routine change just before this aggression started? New people moving in or people moving out. Change in daily routine?
• Is the aggression only there when people are around? Is it associated with certain people? The only way to establish if aggression happens in your absence is to leave a webcam or tape
recorder on to see what happens in your absence.
• Are there any other signs the cat shows which may indicated underlying pain or disease? Limping, excessive thirst, increase in vomiting, weight loss, difficult in urination?

From the background you provided it sounds if Mia is showing dominance aggression and Tigger has now developed a form of fear aggression. It is not clear what collar or diffuser you are using I
am assuming it is the feliway diffuser. I also assume both females are spayed and that this problem been present for more than 4 weeks? Please correct me if my assumptions are incorrect.

Inter cat aggression can be addressed on three different levels:
1. Environmental modification
2. Behavioural modification
3. Medication (last resort)

This problem cannot be assessed in a veterinary clinic consultation and therefore a behaviourist need to come to your house to assess the cats in their home environment to help identify the cause and to
advice on how to modify the behaviour.

Let’s look at the three levels:

1. Environmental modification:
Enrichment of the home environment is very important:
• Have several feeding area/ sand box areas/ hide out places (cat igloos work well) these places must be out of site, smell and hearing distance to allow privacy and safe places.
• Create 3 D levels – put igloos on top of tables, get multi-tier scratch post with resting places
• Have interactive toys available at all times.
• Feliway diffuser need to be plugged in continuously on the level where cats spend most of their time and will only start having effect in 6 weeks of continues use.

2. Behavioural modification:
If environmental modification is not enough or the aggression is severe behavioural modification is advised:
• Positive re-enforcement of good behaviour – reward good behaviour always have treats at hand and give to the cats if they are all calm. Do not punish the aggressive behaviour, not
even verbally this will just add to the anxiety.
• Separation of the problem cats, followed by desensitisation and gradual re-introduction is a labour intensive method but will most likely be the only chance on a more peaceful
interaction. This process takes weeks to months and is best to get input from a registered behaviourist before embarking on this journey. An example follows but it need to be tailor
made to your needs:
1. Keep problem cats separate – they are not even allowed to smell/hear each other initially try for a week.
2. After a week of no contact start introducing them to each other only smell/auditory – feed them on opposite site of a closed/solid (not see through) door. If this results in
hissing go back to step 1 for another week.
3. Swab the rooms – so the cat which was in confinement comes out and the other cat goes in to the same room – to get use to the other cats smell without any threat. Do
that for a week.
4. Keep them on separate sites of a glass door or keep one in a crate while the other come pass – if this results in hissing go back to step 3. Do it for 1 week.
5. If no aggression is showed in step four let them out of confinement but keep all environmental enrichment in place.

3. Medication
The last resort if level 1 and 2 fails and you have seen a behaviourist is to get behavioural modification medicine as a prescription drug from your vet after a clinical examination.
How to choose a cat behaviourist?
There are many dog behaviourist available but cats are very unique when it comes to behaviour and more challenging. Reputable cat behaviourists are not that commonly available. Consider the
following before selecting a behaviourist:
• What qualification does the behaviourist have and is he/she affiliated to a certain governing body?
• Ask for previous testimonials from clients?
• Ask your vet if there is a cat behaviourist they can recommend?
• Contact a reputable dog behaviourist (details from your vet) and asked them if they can recommend a cat behaviourist.

References used:
VIN (Veterinary information network)
http://www.aspca.org/Pet-care/virtual-pet-behaviorist/cat-articles/aggression-between-cats-in-yourhousehold
http://www.petmd.com/cat/conditions/behavioral/c_ct_aggression_intercat?page=2#.UYqgOqL7D9g
http://www.paws.org/aggression-between-cats.html

Article written by: Dr Adel Ferreira