In some of our previous articles, you learnt about internal or endo-parasites of importance in ruminant animals. These animals are also infected with external parasites or ecto-parasites if allowed to thrive may lead to serious economic loss as a result of product devaluation especially as most of these affects the skin and consequently the hides of the animals. The secondary effect may also affect the meat value.
1. Ticks
Ticks are Acarines of high importance as skin parasites. There are two types of ticks namely, hard ticks and soft ticks. The hard ticks are oval in shape, flattened from top to bottom, with a hard protective dorsal surface (scutum) and an anteriorly projecting mouth part.
Soft tick does not have the hard protective dorsal surface. Ticks are vectors of some diseases such as anaplasmosis or gall sickness and heartwater disease. The hard tick has about three species depending on the number of host.
There is the one-host tick, two-host tick and three-host tick. Ticks spend only a short period on their host sucking blood and several days to three weeks are spent on pastures or in the sand where they can be easily attached to unsuspecting host in this case ruminants and even man.
Ticks are treated by the application of acaricides through spraying or dip bath. Pour-on preparation can also be used. Ticks can be controlled by denying host animals to be on the pasture.
The pasture can also be burnt. However, all these are possible in intensive rearing of ruminants or where there is a good control of the animals that graze in the environment.
2. Lice
These are small, flat wingless insects that irritate the body of the ruminants so much that they rub their bodies against solid objects. They live and burrow in the hair and wool of the skin of the animal.
They are visible even to the naked eye as roaming tiny objects on the skin when the hair or the wool is parted by hand. There are two types of lice. These are sucking lice and biting or chewing lice.
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The adult lice live for about one month on the skin of the animal. The female lays about 300 eggs which hatch within three weeks into nymph.
Infested animals constantly get irritated, emaciated, look pale, anaemic and show consistent hitching or rubbing of their body against solid object and thereby damage their skin.

Lice infestation is treated by dip bath, spraying or rubbing of chemicals like permethrin or malathion or by injecting with ivomec. It can be controlled by preventing overcrowding.
3. Mites or Mange
Mites belong to the Acarines and cause skin disease called mange. They are so small that they are not visible by the naked eye.
They also live all their lives on the host. Psoroptes and Chorioptes spp of mites are the superficial burrowing type in the skin while the Demdex and Sarcoptesspp burrow deeper into the skin.
Symptoms of mange include irritation, scratching, biting, rough peeling skin, and loss of hair on the skin.
Treatment is by spraying, dip bath, injection with ivermectin or ivomec and rubbing of malathion powder on the skin of the animals.
4. Flies
Flies are insects that breed during the summer or rainy months of the year. The flies bite the skin and feed on the wound of ruminants. Some of the flies transmit secondary disease.
There are different types of flies viz:
Biting flies that bites and suck blood of the host.
Myiasis flies are those that lay eggs in the open wounds, other natural openings and skin of the animal. They invade and damage the tissue.
Blowfly myiasis or blowfly strike is green in colour and lay their eggs on the skin section soiled with faeces around the hind- quarter.
The eggs hatch into larva which crawl to the skin and gets hooked to it by their mouth hooks. This gives a larva- infested lesions or strike on the animal. This lesion could very distressful and debilitating causing pains and at times death of the animal.
Flies are treated and controlled by spraying, dip bath, use of fly repellants like pour-on etc.
5. Ringworms
This is a fungal infection of the skin of ruminants and even man caused by Microsporum or Trichophyton fungi. It is noticed in animals first by hair loss in a circular form which may be about 3 – 4 cm in diameter.
The hair loss gives way to a greyish and crusty appearance on the skin of the animal. It affects all ages of animals especially when housed together with poor ventilation and sunlight.
Infected animal should be separated and quarantine programme must be made effective where rampart. It is spread by direct contact through the spores of the fungi. It can be treated by oral application of griseofulvin.
In summary, this article has been able to show the characteristics of parasites that lives on ruminant animals if not taken care of and the economic importance to production.
In this article, we have also discussed that external parasites live on the skin of the animal which value is decreased if seriously infested.
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