Ticks

A couple of years ago, I looked after a hedgehog during the winter because when we found it it would have been too small to survive hibernation. During this time we fed it lots and it grew big and fat by spring. However, during this time Twix the hedgehog got some ticks. We read in the St Tiggywinkles Animal Care book that ticks should be left and they will fall off eventually. So this is what we did and after some time, the ticks fell off and we never thought twice about them.

But, a few months ago, my dog got a tick. At first we were unsure of what to do, however we assumed that this case would be very similar to the hedgehog one, although the tick was a lot smaller and looked very different. But after leaving it for a few days we could see no progress from my careful monitoring, so we looked to the internet. Reading on lots of sites various methods to remove ticks, we thought we had better try something. Action was provoked when, the same evening as we were doing research, I looked to Simba and saw that his nose was covered in blood. Quickly assessing, I realised that this must have been caused by the tick. Looking back on it now, I think that he must have brushed against something or scratched himself, causing the tick to detach slightly from his skin. As I cleaned up his nose with antiseptic to get a better look, we resorted to the most convenient and quickest option we had read. This was to apply alcohol. Apparently, covering the tick in alcohol paralyses it and therefore loosens its jaw and causes it to fall off. Dabbing on some whisky, the parasite immediately fell off on the cotton bud leaving Simba fit, healthy and unaffected.

But the tick problem came back to haunt us. When on holiday in August in North Yorkshire with Simba, I was brushing him when I came across a burr stuck in his fur. This is not an unusual occurance for Simba, as he loves to dig around in the bushes. However, on closer inspection, I saw that this burr was not going to be pulled out easily. In fact, it was another tick. After having spent time on work experience at Kingsnorth Vets, I had seen a tick remover being used for the obvious purpose of removing ticks. Now I knew that alcohol was probably not the best option, and so we went in search of a pet shop. Here we bought a tick remover in two different sizes and removed the nuisance with a quick twist. Problem solved.

Tick Remover

But what is a tick?

From my experience, ticks are very interesting creatures. They are parasites and attach themselves to animals (including humans) to drink blood until they have had their fill so drop off.

On looking further into it, I have discovered that they are in the arachnid family, hence the eight legs, in the order Ixodida (leach). They can also carry a number of diseases.

What especially interests me at the moment, is the significant difference I was able to observe between the ticks on the hedgehog and those on Simba. This must be down to species.

 

Classification of the Tick

This shows the classification of the tick, of which there are three families. The family nuttalliellidae only contains one species. This is found in Southern Africa so is of no significance to me. There are also hard ticks and soft ticks, hard being the most common.

But whatever the tick, there is always a prominent risk of infection from them. It is made especially bad because ticks often carry multiple pathogens, all of which can be passed into the body if the tick is not removed as quickly as possible. The most well known one of these is Lyme Disease which is caused by at least three species of bacteria. However, other illnesses include carried by bacteria, viruses and toxins which can pass into the body. Although most of these diseases are not life threatening to an animal, it is very important to remove ticks from pets as quickly as possible. This is the best form of prevention and although ticks are strange, yet fascinating creatures, they should not be allowed to accompany one’s for any longer than necessary.

References

http://en.wikipedia.org/wiki/Tick

http://www.dartmoorcam.co.uk/dartmoortickwatch/photos/photos.htm

The Ethiopian Wolf

This summer, I am going on an expedition to Ethiopia with my school. So when I came across an article on the Ethiopian Wolf in the BBC Wildlife magazine, I was especially interested.

Ethiopian wolves are the world’s rarest dog and their numbers are rapidly declining, with a prediction of less than 450 individuals remaining in the wild. This is because of other dogs who came to the highlands of Ethiopia with the human population. These dogs are semi-feral and are often left to their own devices to run wild. Because of this, they hunt the same rodent food as the Ethiopian wolves, leaving the wolves in danger of not getting enough food for themselves or their families. Although this may sound concerning, a greater worry is the diseases the dogs bring. These diseases can easily pass to the wolves through contact with infected dogs or even dead infected animals and these can then pass to the entire wolf pack. The most prominent of these are rabies and canine distemper virus (CDV).

Everyone has heard of rabies. It is that disease which is carried by dogs and fatal. I remember reading the ‘Roman Mysteries’ books by Caroline Lawrence when I was younger and I remember when I first came across this terrifying disease in the first book, ‘The Thieves of Ostia’. Although this is only a children’s book, it is based on underlying fact. According to it, rabies ’causes fatal hydrophobia’ – the fear of water.
When looking at some more scientific resources, rabies is in fact a virus. It is neurotropic, meaning that it preferentially infects nerve cells. This of course leads the disease to damage the central nervous system. To get to the CVN the rabies can travel from the wound in which it has entered, along the neural pathways extremely quickly. This, as well as the binding to an interferon antagonist (http://en.wikipedia.org/wiki/Interferon) protein helps to decrease the immune response. Having entered the CVN, the rest of the body is promptly infected, leading to symptoms starting with behavioural changes, then hyper-reactivity and madness, then paralysis because of damaged motor neurones, and finally death by respiratory arrest.
This rapid infection and almost immediate death can be obviously seen as a huge risk to any population, especially one as rare as the Ethiopian wolves.

I have also come acroos Canine Distemper Virus and I know that this, unlike rabies, is a problem in the UK. As its name suggests, this is also a viral infection and most commonly affects dogs and ferrets. I can immediately see the risk this must be to any animal, as it is spread through aerosol droplets, rather than open wounds. This means that it can be caught through a dog simply sniffing infected urine, faeces or drinking from water which contains the contaminated fluid. Once in the body, CDV initially replicates in the tissues of the respiratory tract, before progressing into the blood stream to infect many other cells, including those of the central nervous system. It also suppresses the immune system by decreasing the tissue responsible for producng antibodies (lymphoid depletion), this results in a high risk of secondary infections. The suffering of an infected animal is most prominent in gastrointestinal and respiratory symptoms like diarrhea and laboured breathing. But more seriously, neurological symptoms can arise which are likely to be life threatening.
In England, symptoms such as these can be readily identified and efforts can be made to treat the dog, but for a wild, such as the Ethiopian Wolf, there is little chance of survival.

After looking into these diseases, I have realised the threat human settlement poses to the Ethiopian Wolf, and the need for us to change the direction this population is taking and ensure that sufficient vaccination programmes take place. Rabies has been eradicated in the UK due the success of vaccination; could vaccination offer the same hope for Ethiopia and the stunning wolves that live here?

References

http://en.wikipedia.org/wiki/Rabies_virus

http://en.wikipedia.org/wiki/Rabies

http://en.wikipedia.org/wiki/Canine_distemper

http://www.ethiopianwolfproject.com/