Possibly the most common problem in pets in Darwin is itch. Many pet owners that are new to the Territory complain about their pets skin. Many pets did not have a problem when Down South but since moving to the Territory the scratching wont stop.
Understandably this is a frustrating issue. Not only does it cause significant distress for the pet and the owner but it is often a difficult issue to fix.
So what causes itch?
Our pets can be itchy for varying reasons with dogs and horses the most affected in the Top
End. Itch in dogs will usually come from one of three reasons
- Parasites
- Infection
- Allergies
Some dogs will have all these causes contributing to itch whilst some will have just one. Trying to work out which of the three reasons is contributing to itch is the cornerstone to resolving the problem.
Parasites
Thankfully fleas are rarely seen anymore in Darwin thanks to the high
quality tablets and top spots that are used for their control. However,
ticks are still prevalent and whilst they may not be as itchy as fleas their
bite will still cause scratching.
Mites are the most common cause of parasite induced itch and in
Darwin can come in various forms. Mites that cause mange such as
Demodex and Scabies need to be ruled out but mites can also come
from poultry, feed and hay. These insects can be hard to find but are
easy to treat. You can use products like Bravecto, Nexgard, or Simparica
Infection
Many dogs in humid climate will at some point get skin
infections. These are usually in the form of bacteria,
yeast and fungal infections and can be any where over
the body.
These infections can have variable levels of itch and
sometimes be painful. Infection may come from over
scratching, excessive wetting such as swimming in the
pool and not drying in the humid climate. Some dogs
have a reduced ability to fight bacteria or yeast on the
skin which can be made worse from the humid climate.
Testing the skin and looking at samples under the microscope is the only way of knowing if
infection is present and what type it is. It also helps vets decide how much infection is there and
how deep it is which then determines what tablets, shampoos or topical treatments may be
required to treat the problem.
Allergies
Possibly the most common cause of itchy skin in dogs in Darwin is allergic skin disease. This is
a challenging problem that is most likely to appear after the age of 1 year old. Whilst both food
and environmental factors can create allergies, it is thought that only up to 10% of itch is caused
by food. This is why a change of diet rarely resolves skin issues in dogs in Darwin.
The rest of the itch usually comes from environmental factors. These include trees, grasses,
pollens, and sometimes moulds and insect particles. These environmental factors are usually
inhaled but sometimes in contact with the skin. Just like Hayfever in humans cause sneezing
and itchy eyes, in dogs inhaling these allergens in dogs causes itchy skin.
But why are there so many more allergens in Darwin as
opposed to any where else in the country? A few theories
exist around this. First, is that with our tropical climate
there are more plants flowering, weeds growing and
more moulds than our southern counterparts. Pollen
counts down south will be broadcast on the news and
can be mapped – for us pollen counts are high all year
round.
Secondly, during storm season allergens can become
prolific. When thunderstorms occur the wind will sweep
up allergens and plant material in to the air.
Lightning can hit the material and make the particles smaller. When they fall to the ground, we
can breathe them in more easily. This is why asthma may be worse in thunder storms. It is
possible that this also contributes to allergies in dogs.
The problem is that curing an allergy is hard. The only ways to try are allergy testing and
immunotherapy. However, these methods do not always work.
So What Can we Do?
We can treat any external parasites and secondary infection on the skin. Then assess the level
of itch and find a management strategy that controls the itch. This strategy will be different for
each individual dog and will depend on their individual levels of reaction.
Sometimes allergies are seasonal, sometimes they are all year round. The levels of reaction will
change throughout the seasons.
This means skin may need different types of medication at different times of the year. Regular
checks and keeping the skin clean are important for good skin care. However,r, anti-allergy
medication is often needed and usually taken for life.
Author Dr Susanna Callow BSc BVMS MVS
12 March 2025