Parasites
In Australia, Jason and his family own a horse called “Lightning”, and he takes the responsibility of caring for the horse very seriously. Occasionally, while giving him a good brush down following a ride, he will find a small unwelcome traveller that has also managed to hitch a ride on his horse – a tick! With an active lifestyle that involves trotting through fields and alongside bushes, it is not uncommon for this to occur, so Jason knows what to do. While the tick can be manually removed, Jason’s vet made him aware that ticks can transfer serious diseases and recommends to protect the horse against ticks with for example a repellent spray.
Parasites are a common concern for animals and the people who take care of them. While many are harmless, some can present serious threats to animals and people. The parasite can cause disease itself ( e.g. worms causing scouring and malnutrition; blood parasites causing anaemia) or ….parasite-borne diseases such as Lyme disease, Rocky Mountain spotted fever and meningoencephalitis can be transmitted from animals to people (these diseases are called zoonoses).
In general, there are two types of parasites: endoparasites and ectoparasites. Endoparasites live inside the host (i.e, inside the animal that carries – or ‘hosts’ – it), affecting the gastrointestinal tract, liver, or other internal organs. The most common endoparasites of companion animals are worms. Ectoparasites live on the host, affecting skin, fur, or ears. The most obvious ectoparasites are fleas and ticks.
Fleas
One of the most notorious ectoparasites – and the bane of dog and cat owners around the world – is the flea. Fleas live off blood from their hosts and the intake of a female flea can be equivalent to more than 15 times its body weight. When receiving regular meals this way, fleas can survive on a host for up to 140 days. Several thousands of eggs are laid by female fleas and dropped wherever the host animal goes. The warm temperature and humidity in homes provide a favourable microclimate for multiple flea life cycles. Flea infestation can disrupt the general well-being of all animals, causing itchiness, redness, hair loss, and in certain cases severe skin infections. Once fleas have settled down in your home, it too will need to be included in the flea eradication programme. Fleas may also transmit tapeworms to your pet and if pet owners are not careful they may unfortunately be infected from their pet with the same tapeworm.
Ticks
Larger and easier to detect than fleas, but by no means less bothersome, are ticks. Most ticks seek hosts by crawling up the stems of grass or perch on the edges of leaves on the ground in a typical posture with the front legs extended (a behaviour called questing). Others are so-called nest parasites, questing in sheltered environments. As soon as a suitable host brushes against their extended front legs, the questing tick climbs onto its body, holds on tight, bores into the skin and begins to draw tissue fluids such as blood. A tick bite not only causes a localized infection, it can also serve as the portal through which serious diseases are transmitted. These can have a severe impact on the animal’s well being. Ticks can transmit disease agents such as viruses, bacteria, and protozoa to not only animals but also to people.
Worms
Far harder to detect, and in many ways more dangerous are endoparasites, the most common of which are worms. Worm infestations rank among the most critical of parasitic infection in cats, dogs, and horses but also in livestock if not treated. Worms can be very difficult to detect. The indications of disease depend on the defences of the affected animal and the extent of the infestation. They range from signs of general ill-health such as a dull coat and occasional vomiting to a weakened immune system due to massive loss of blood resulting in anaemia, intestinal obstruction, reduction of weight gain (livestock) and even death. Some of these worms can even be transmitted to people from pets if the infection is not checked.
Because the consequences of worm infestation can be so serious, it is easy to understand why veterinarians recommend that cats, dogs, and horses be dewormed regularly
Advances in treatment
Broad-spectrum anthelmintics have been developed that are effective against parasitic worm infections in people and animals. Routinely applied, these products expel worms by either stunning or killing them. In the case of a high risk of tapeworms, extra special treatment may occasionally be necessary as these parasites grow much more quickly. Regular check-ups and preventative action and guidelines for owners are vital to avoid these kinds of infections and infestations.
In a world without animal health products, our pets and livestock animals would be at the total mercy of these invasive pests, causing irritation, pain and death. Due to the huge amounts of potential parasites that animals might be carrying, there is a risk that people may become infected or infested from affected animals and this could be severe. Thankfully, we live in a world where these pests can be detected and controlled, making for altogether more pleasant interactions between animals and peoples – like Celine and her horse.
