Summary

Ticks can cause extensive damage to hides and skins as well as spreading diseases to animals and humans. The financial implications associated with tick infestation due to reduced meat and milk yields as well as the risk of potentially fatal diseases have encouraged farmers in some countries to introduce eradication programmes.

The tick

Ticks are blood-sucking members of the Arachnid family – the same family as spiders. There are two types of tick; hard-bodied ticks which have a hard shield made of chitin over their body and soft- bodied ticks which have a leathery skin. Unlike many other ectoparasites, ticks are not particularly host-specific, ie they can be found infesting many species of animal, although at certain stages of their life cycle they may prefer a particular host species. Ticks are found worldwide and in some countries are considered a serious pest, not only for the damage they cause to hides and skins, but they can transmit potentially fatal diseases, eg Lyme disease which can affect domestic animals and humans. Lyme disease gets its name from the town Lyme in the USA where the disease was first identified. It is caused by a bacterium that is transmitted by ticks. From the farmers’ perspective, severe tick infestations can also lead to anaemia and lack of meat/milk yields in addition to the transmission of diseases. In some countries, eg Australia, a potentially fatal cattle disease called Tick Fever (babesiosis), is a severe problem for farmers.

Tick damage to leather

Ticks feed by inserting their large, sharp mouthpart (proboscis), deep into the skin enabling them to suck the host animal’s blood. The tick’s body will increase dramatically during feeding until they become so engorged with blood that they look like they will burst, hence the saying ‘as tight as a tick’. Ticks are slow feeders and it can take several days before they become engorged. The saliva of the tick contains anti-coagulants making blood uptake easier. Some animals can have an adverse reaction to this saliva and the proboscis has many backward-pointing barbs that stop the creature falling off its host.

Needless to say, this causes extensive damage to the hide or skin. The barbs on the proboscis are so effective at holding on that I have seen ticks that have managed to survive the entire leather making process – tick infested shoe upper leather!

The damage may range from what appears to be an enlarged hair follicle through to a deep scar that is visible on the suede side of the leather. Because the scar tissue is much denser than the surrounding leather it often appears a paler colour because the dye is unable to penetrate properly.

Usually ticks will attach themselves to the areas of the animal where there is least hair and thinnest skin.

Invariably this is on the animals’ underparts, legs and under the tail. In some species they may infest the head and ears.

Tick life cycle

Ticks go through four phases in their life cycle, egg – larva – nymph – adult. Depending on the species, some may stay on the one host from larva through to adult, others may change host up to three times at the different stages of their life cycle.

The adult female ticks feed on the host until they are engorged with blood. Depending on the species, this is usually around two weeks. They then drop off the host to lay their eggs. Typically, about 5,000 eggs are laid, but in some species up to 20,000 are produced. When the eggs hatch, the larvae climb up to the top of tall grass or other vegetation and wait for an animal to pass by.

Consequently, ticks are much more prevalent in areas where there is plenty of vegetation. The larvae feed on the animal until they moult into nymphs. Depending on the species of tick, they may fall to the ground to do this, or stay on their existing host. They then go on to moult into adults and the cycle begins again.

Tick control

Because ticks spend some time on and some time off their host there are two potential means of control. Barns and yards where animals are housed can be sprayed with insecticide. Similarly, areas where animals graze can be sprayed if high numbers of ticks are found. Tick numbers in grazing areas can be estimated by dragging a white towel over the grass. The ticks are fooled into thinking it is a passing animal and will attach themselves to the towel. Damp areas with long grass are likely habitats for ticks. Ticks on the animal can be controlled by spraying with suitable insecticides or by injecting with a systemic tickacide. Ticks are most prevalent during the summer months and this is when such control measures should take place. If it is possible, removal of animals from the grazing area for a prolonged period (up to a year) can eradicate tick infestation since the ticks and their larvae will starve without a host.

In some countries, Tick Fever in cattle, which is spread by two species of tick, can be such a threat that extreme measures are taken involving a carefully controlled programme of eradication. In Texas, USA, such a programme was introduced in 1906 and by 1961 Tick Fever was eradicated. As a precaution, the border between Texas and Mexico is still patrolled to ensure that infested cattle do not cross the border.

* Leather Wise Ltd provide professional problem solving and arbitration services relating to leather and leather products, as well as training courses tailored to fulfil customers’ requirements in all aspects of leather production and use in consumer products. For further information contact Chris Powley-Williams or Amanda Michel on +44 1604 497568 or visit [http://www.leatherwise.co.uk]